Formulas ======== - :doc:`(doc) ` :code:`conditions.dynamics.equilibrium` .. toggle:: - :doc:`(doc) ` Total torque is zero .. math:: \tau = 0 - :doc:`(doc) ` :code:`conditions.thermodynamics.dielectrics` .. toggle:: - :doc:`(doc) ` Equation of state .. math:: D = f{\left(E,T,\rho \right)} - :doc:`(doc) ` :code:`definitions` .. toggle:: - :doc:`(doc) ` Acceleration is speed derivative .. math:: a{\left(t \right)} = \frac{d}{d t} v{\left(t \right)} - :doc:`(doc) ` Admittance is inverse impedance .. math:: Y = \frac{1}{Z} - :doc:`(doc) ` Angular acceleration is angular speed derivative .. math:: \alpha{\left(t \right)} = \frac{d}{d t} \omega{\left(t \right)} - :doc:`(doc) ` Angular speed is angular distance derivative .. math:: \omega{\left(t \right)} = \frac{d}{d t} \theta{\left(t \right)} - :doc:`(doc) ` Angular wavenumber is inverse wavelength .. math:: k = \frac{2 \pi}{\lambda} - :doc:`(doc) ` Boltzmann factor via state energy and temperature .. math:: f = \exp{\left(- \frac{E_{i}}{k_\text{B} T} \right)} - :doc:`(doc) ` Compliance is inverse stiffness .. math:: c = \frac{1}{k} - :doc:`(doc) ` Compressibility factor is deviation from ideal gas .. math:: Z = \frac{p V}{n R T} - :doc:`(doc) ` Current is charge derivative .. math:: I{\left(t \right)} = \frac{d}{d t} q{\left(t \right)} - :doc:`(doc) ` Damped harmonic oscillator equation .. math:: \frac{d^{2}}{d t^{2}} x{\left(t \right)} + 2 \zeta \omega \frac{d}{d t} x{\left(t \right)} + \omega^{2} x{\left(t \right)} = 0 - :doc:`(doc) ` Density from mass and volume .. math:: \rho = \frac{m}{V} - :doc:`(doc) ` Electrical conductance is inverse resistance .. math:: G = \frac{1}{R} - :doc:`(doc) ` Harmonic oscillator is a second order derivative equation .. math:: \frac{d^{2}}{d t^{2}} x{\left(t \right)} = - \omega^{2} x{\left(t \right)} - :doc:`(doc) ` Heat capacity ratio .. math:: \gamma = \frac{C_{p}}{C_{V}} - :doc:`(doc) ` Impedance is resistance and reactance .. math:: Z = R + i X - :doc:`(doc) ` Impulse is integral of force over time .. math:: J = \int\limits_{t_{0}}^{t_{1}} F{\left(t \right)}\, dt - :doc:`(doc) ` Intensity of sound wave is rate of energy transfer over area .. math:: I = \frac{P}{A} - :doc:`(doc) ` Linear coefficient of thermal expansion .. math:: \alpha_{l} = \frac{\frac{\partial}{\partial T} l{\left(T,p \right)}}{l{\left(T,p \right)}} - :doc:`(doc) ` Lorentz factor .. math:: \gamma = \frac{1}{\sqrt{1 - \frac{v^{2}}{c^{2}}}} - :doc:`(doc) ` Mass flow rate .. math:: \mu{\left(t \right)} = \frac{d}{d t} m{\left(t \right)} - :doc:`(doc) ` Mass fraction of mixture component .. math:: w_{i} = \frac{m_{i}}{m} - :doc:`(doc) ` Mechanical energy is kinetic and potential energy .. math:: E = K + U - :doc:`(doc) ` Momentum is mass times speed .. math:: p = m v - :doc:`(doc) ` Net force is sum of individual forces .. math:: F = \sum_i {F}_{i} - :doc:`(doc) ` Number density is number of objects per unit volume .. math:: n = \frac{N}{V} - :doc:`(doc) ` Period from angular frequency .. math:: T = \frac{2 \pi}{\omega} - :doc:`(doc) ` Power is energy derivative .. math:: P{\left(t \right)} = \frac{d}{d t} E{\left(t \right)} - :doc:`(doc) ` Quality factor is ratio of energies .. math:: Q = \frac{\omega E}{P} - :doc:`(doc) ` Radiant exitance is radiant flux emitted per unit area .. math:: M_\text{e} = \frac{d}{d A} \Phi_\text{e}{\left(A \right)} - :doc:`(doc) ` Relative refractive index is ratio of wave speeds .. math:: n = \frac{v_\text{incident}}{v_\text{refracted}} - :doc:`(doc) ` Rotational inertia is mass times squared radius .. math:: I = m r^{2} - :doc:`(doc) ` Sound level in decibels .. math:: L_{I} = L_{I0} \log_{10} \left( \frac{I}{I_0} \right) - :doc:`(doc) ` Speed is distance derivative .. math:: v{\left(t \right)} = \frac{d}{d t} s{\left(t \right)} - :doc:`(doc) ` Temporal frequency from period .. math:: f = \frac{1}{T} - :doc:`(doc) ` Temporal frequency is number of events per unit time .. math:: f = \frac{N}{t} - :doc:`(doc) ` Thermal de Broglie wavelength .. math:: \lambda = \hbar \sqrt{\frac{2 \pi}{m k_\text{B} T}} - :doc:`(doc) ` Thermal resistance to conduction .. math:: R_\text{val} = \frac{h}{k} - :doc:`(doc) ` Thermodynamic compressibility .. math:: \beta = - \frac{\frac{\partial}{\partial p} V{\left(p,q \right)}}{V{\left(p,q \right)}} - :doc:`(doc) ` Volumetric coefficient of thermal expansion .. math:: \alpha_{V} = \frac{\frac{\partial}{\partial T} V{\left(T,q \right)}}{V{\left(T,q \right)}} - :doc:`(doc) ` Wave equation in one dimension .. math:: \frac{\partial^{2}}{\partial x^{2}} u{\left(x,t \right)} = \frac{\frac{\partial^{2}}{\partial t^{2}} u{\left(x,t \right)}}{v^{2}} - :doc:`(doc) ` :code:`definitions.vector` .. toggle:: - :doc:`(doc) ` Acceleration is velocity derivative .. math:: {\vec a} \left( t \right) = \frac{d}{d t} {\vec v} \left( t \right) - :doc:`(doc) ` Angular momentum is position cross linear momentum .. math:: {\vec L} = \left[ {\vec r}, {\vec p} \right] - :doc:`(doc) ` Damping force is proportional to velocity .. math:: {\vec F} = - b {\vec v} - :doc:`(doc) ` Momentum is mass times velocity (Vector) .. math:: {\vec p} = m {\vec v} - :doc:`(doc) ` Net force vector is sum of forces .. math:: {\vec F} = \sum_i {{\vec F}}_{i} - :doc:`(doc) ` Vector area is unit normal times scalar area .. math:: {\vec A} = {\vec n} A - :doc:`(doc) ` Velocity is position vector derivative .. math:: {\vec v} \left( t \right) = \frac{d}{d t} {\vec d} \left( t \right) - :doc:`(doc) ` :code:`laws.astronomy` .. toggle:: - :doc:`(doc) ` Absolute magnitude from apparent magnitude and distance .. math:: M = m - 5 \log_{10} \left( \frac{d}{d_0} \right) - :doc:`(doc) ` Angular altitude in upper culmination .. math:: h = 90^\circ - \phi + \delta - :doc:`(doc) ` Approximate lifetime of stars located on the main sequence .. math:: t = t_\odot \frac{m}{M_\odot} \frac{L_\odot}{L} - :doc:`(doc) ` Change in apparent magnitude from distance .. math:: m_{2} - m_{1} = - 2.5 \log_{10} \left( \frac{E_{\text{e}2}}{E_{\text{e}1}} \right) - :doc:`(doc) ` Latitude from zenith angle and declination .. math:: \phi = \frac{\theta_\text{S} - \theta_\text{N} + \delta_\text{S} + \delta_\text{N}}{2} - :doc:`(doc) ` Lifetime of star on main sequence .. math:: t = 10 \, \text{Gyr} \left(\frac{m}{M_\odot}\right)^{1 - n} - :doc:`(doc) ` Luminosity of star from absolute magnitude .. math:: \log_{10} \left( \frac{L}{L_0} \right) = - 0.4 M - :doc:`(doc) ` Luminosity of Sun in future from luminosity in present .. math:: L_{1} = L \left(\frac{5.59}{\frac{t}{1 \, \text{Gyr}}} - 1.41 + 0.26 \frac{t}{1 \, \text{Gyr}}\right) - :doc:`(doc) ` Luminosity of Sun in past from luminosity in present .. math:: L_{0} = \frac{L}{1 + 0.4 \left(1 - \frac{t}{1 \, \text{Gyr}} \frac{1}{4.6}\right)} - :doc:`(doc) ` Radius of planetary orbits from number .. math:: r = a + b 2^{N} - :doc:`(doc) ` Ratio of luminosities from ratio of masses of stars .. math:: \frac{L_{2}}{L_{1}} = \left(\frac{m_{2}}{m_{1}}\right)^{4} - :doc:`(doc) ` Speed of galaxy from distance to galaxy .. math:: v = H d - :doc:`(doc) ` :code:`laws.astronomy.relativistic` .. toggle:: - :doc:`(doc) ` Relative rocket speed from mass change and effective exhaust speed .. math:: \frac{m_{1}}{m_{0}} = \left(\frac{1 - \frac{v}{c}}{1 + \frac{v}{c}}\right)^{\frac{c}{2 v_\text{e}}} - :doc:`(doc) ` :code:`laws.chemistry` .. toggle:: - :doc:`(doc) ` Avogadro constant is particle count over amount of substance .. math:: N_\text{A} = \frac{N}{n} - :doc:`(doc) ` Boundary of thermalization zone of atomized atoms in magnetron .. math:: l = N \lambda - :doc:`(doc) ` Distance of greatest convergence of particles in magnetron .. math:: d = - d_0 \left(Z_{1}^{0.0387} + Z_{2}^{0.0387}\right) \log \left( \frac{V}{V_0 \left(Z_{1} Z_{2}\right)^{1.4883}} \right) - :doc:`(doc) ` Electron distribution function in gas plasma per Druyvestein .. math:: f = \frac{E_0 \sqrt{e V}}{E^{\frac{3}{2}}} \exp{\left(- \frac{0.55 \left(e V\right)^{2}}{E^{2}} \right)} - :doc:`(doc) ` Electron distribution function in gas plasma per Maxwell .. math:: f = \frac{E_0 \sqrt{e V}}{E^{\frac{3}{2}}} \exp{\left(- \frac{1.55 e V}{E} \right)} - :doc:`(doc) ` Electron current in probe circuit in gas plasma .. math:: I = 0.25 A e n \sqrt{\frac{8 k_\text{B} T}{\pi m_\text{e}}} \exp{\left(- \frac{e \left(U_\text{f} - U_{\vec E}\right)}{k_\text{B} T} \right)} - :doc:`(doc) ` Energy transfer coefficient for elastic scattering in magnetron .. math:: x = \frac{2 m_{1} m_{2}}{\left(m_{1} + m_{2}\right)^{2}} - :doc:`(doc) ` Etch rate of target in magnetron .. math:: v = \frac{j M Y}{e \rho N_\text{A}} - :doc:`(doc) ` Interaction cross section in Coulomb's interaction model .. math:: \sigma = \frac{e^{2}}{2 \pi \varepsilon_0^{2} E_\text{i}^{2}} - :doc:`(doc) ` Interaction cross section in elastic interaction model .. math:: \sigma = \pi D^{2} \left(1 + \frac{S}{T}\right) - :doc:`(doc) ` Interaction cross section in model of hard spheres .. math:: \sigma = \pi d^{2} - :doc:`(doc) ` Interaction cross section in recharge model .. math:: \sigma = \pi a_0^{2} \frac{\mathrm{IE}_\text{H}}{E_\text{i}} \log \left( \sqrt{\frac{3 k_\text{B} T}{m}} \sqrt{\frac{E_\text{i}}{\mathrm{IE}_\text{H}}} \frac{\sigma p m}{2 k_\text{B} T e E} \right)^{2} - :doc:`(doc) ` Ionization cross section of atom by electrons per Granovsky .. math:: \sigma_\text{eff} = \sigma_\text{max} \frac{E - \sigma_\text{i}}{E_\text{max} - \sigma_\text{i}} \exp{\left(\frac{E_\text{max} - E}{E_\text{max} - \sigma_\text{i}} \right)} - :doc:`(doc) ` Ionization cross section of atom by electrons per Lotz-Drevin .. math:: \sigma = \frac{2.66 \pi a_0^{2} N \mathrm{IE}_\text{H}^{2}}{E_\text{i}^{2}} \frac{A \left(\frac{E}{E_\text{i}} - 1\right)}{\left(\frac{E}{E_\text{i}}\right)^{2}} \log \left( 1.25 B \frac{E}{E_\text{i}} \right) - :doc:`(doc) ` Mass of film deposited during electrolysis .. math:: m = \frac{I M B t}{v \mathfrak{F}} - :doc:`(doc) ` Mean free path of particles in gaseous medium .. math:: \lambda = \frac{k_\text{B} T}{\sqrt{2} p \sigma} - :doc:`(doc) ` Molar mass via molecular mass .. math:: M = m_{0} N_\text{A} - :doc:`(doc) ` Number density via volumetric density and molar mass .. math:: n = \frac{\rho N_\text{A}}{M} - :doc:`(doc) ` Number of collisions of particle with gas in magnetron .. math:: N = \frac{\log \left( \frac{E}{E_{0}} \right)}{\log \left( 1 - x \right)} - :doc:`(doc) ` Reaction equilibrium constant via standard Gibbs energy .. math:: K = \exp{\left(- \frac{\Delta G}{R T} \right)} - :doc:`(doc) ` Speed of charged particles in gas via mobility .. math:: v = \frac{\mu E}{p} - :doc:`(doc) ` Volumetric ionization coefficient of neutral particles by electrons .. math:: \alpha = A p \exp{\left(- \frac{B p}{E} \right)} - :doc:`(doc) ` :code:`laws.chemistry.electrochemistry` .. toggle:: - :doc:`(doc) ` Electrochemical equivalent from molar mass and valence .. math:: Z = \frac{M}{\mathfrak{F} v} - :doc:`(doc) ` Energy of electron in hydrogen atom per Bohr .. math:: E = \frac{e^{2}}{8 \pi \varepsilon_0 r} - :doc:`(doc) ` Mass of substance deposited on electrode .. math:: m = Z I t - :doc:`(doc) ` :code:`laws.chemistry.potential_energy_models` .. toggle:: - :doc:`(doc) ` Lennard-Jones potential .. math:: U = 4 \varepsilon \left(\left(\frac{\sigma}{r}\right)^{12} - \left(\frac{\sigma}{r}\right)^{6}\right) - :doc:`(doc) ` :code:`laws.condensed_matter` .. toggle:: - :doc:`(doc) ` Concentration of intrinsic charge carriers .. math:: n = \sqrt{N_\text{c} N_\text{v}} \exp{\left(- \frac{E_\text{g}}{2 k_\text{B} T} \right)} - :doc:`(doc) ` Current density from mobility .. math:: j = e \left(- n_\text{e} \mu_\text{e} + n_\text{h} \mu_\text{h}\right) E - :doc:`(doc) ` Current density in thermionic emission per Richardson .. math:: j = a T^{2} \exp{\left(- \frac{W}{k_\text{B} T} \right)} - :doc:`(doc) ` Current density via number density and drift velocity .. math:: j = q n u - :doc:`(doc) ` Diffusion coefficient from energy and temperature .. math:: D = D_{0} \exp{\left(- \frac{E_\text{A}}{k_\text{B} T} \right)} - :doc:`(doc) ` Drift velocity of charge carriers .. math:: u = \mu E - :doc:`(doc) ` Effective mass of electron via energy .. math:: m_\text{eff} = \frac{\hbar^{2}}{\frac{d^{2}}{d k^{2}} E{\left(k \right)}} - :doc:`(doc) ` Equilibrium voltage difference in p-n junction via concentrations .. math:: \Delta V = \frac{k_\text{B} T}{q} \log \left( \frac{n_\text{d} n_\text{a}}{n^{2}} \right) - :doc:`(doc) ` Resistance from temperature .. math:: R = R_{0} \left(1 + a \left(T - T_\text{std}\right)\right) - :doc:`(doc) ` :code:`laws.conservation` .. toggle:: - :doc:`(doc) ` Abbe invariant of two optical environments is constant .. math:: n_{0} \left(\frac{1}{d_\text{o}} - \frac{1}{r}\right) = n \left(\frac{1}{d_\text{i}} - \frac{1}{r}\right) - :doc:`(doc) ` Amount of mixture is sum of amounts of components .. math:: n = \sum_i {n}_{i} - :doc:`(doc) ` Charge is constant .. math:: \frac{d}{d t} q{\left(t \right)} = 0 - :doc:`(doc) ` Initial mass equals final mass .. math:: m{\left(t_{1} \right)} = m{\left(t_{0} \right)} - :doc:`(doc) ` Initial mechanical energy equals final mechanical energy .. math:: E{\left(t_{1} \right)} = E{\left(t_{0} \right)} - :doc:`(doc) ` Initial momentum equals final momentum .. math:: p{\left(t_{1} \right)} = p{\left(t_{0} \right)} - :doc:`(doc) ` Mass is constant .. math:: \frac{d}{d t} m{\left(t \right)} = 0 - :doc:`(doc) ` Mechanical energy is constant .. math:: \frac{d}{d t} E{\left(t \right)} = 0 - :doc:`(doc) ` Mixture mass is sum of component masses .. math:: m = \sum_i {m}_{i} - :doc:`(doc) ` Momentum is constant .. math:: \frac{d}{d t} p{\left(t \right)} = 0 - :doc:`(doc) ` :code:`laws.dynamics` .. toggle:: - :doc:`(doc) ` Acceleration is force over mass .. math:: a = \frac{F}{m} - :doc:`(doc) ` Braking path via speed and friction force .. math:: s = \frac{m v^{2}}{2 F_\text{fr}} - :doc:`(doc) ` Buoyant force from density and volume .. math:: F_\text{A} = \rho g V - :doc:`(doc) ` Coefficient of stiffness from area and length .. math:: k = \frac{E A}{l} - :doc:`(doc) ` Displacement in forced non-resonant oscillations .. math:: q{\left(t \right)} = \frac{\frac{F}{m} \cos{\left(\omega t + \varphi \right)}}{\omega_{0}^{2} - \omega^{2}} - :doc:`(doc) ` Force is derivative of momentum .. math:: \frac{d}{d t} p{\left(t \right)} = F{\left(t \right)} - :doc:`(doc) ` Forced oscillations equation .. math:: \frac{d^{2}}{d t^{2}} x{\left(t \right)} + \omega_{0}^{2} x{\left(t \right)} = \frac{F}{m} \cos{\left(\omega t + \varphi \right)} - :doc:`(doc) ` Friction force from normal force .. math:: F_\text{fr} = \mu N - :doc:`(doc) ` Instantaneous power is force times speed .. math:: P = F v \cos{\left(\varphi \right)} - :doc:`(doc) ` Kinetic energy from mass and speed .. math:: K = \frac{m v^{2}}{2} - :doc:`(doc) ` Kinetic energy from rotational inertia and angular speed .. math:: K = \frac{I \omega^{2}}{2} - :doc:`(doc) ` Kinetic energy via momentum .. math:: K = \frac{p^{2}}{2 m} - :doc:`(doc) ` Maximum height from initial speed .. math:: h = \frac{v^{2}}{2 g} - :doc:`(doc) ` Mechanical work is force times distance .. math:: W = F s - :doc:`(doc) ` Momentum derivative of kinetic energy is speed .. math:: \frac{d}{d p{\left(v \right)}} K{\left(p{\left(v \right)} \right)} = v - :doc:`(doc) ` Period of ideal pendulum from length .. math:: T = 2 \pi \sqrt{\frac{l}{g}} - :doc:`(doc) ` Period of physical pendulum .. math:: T = 2 \pi \sqrt{\frac{I}{m g d}} - :doc:`(doc) ` Period of spring from mass .. math:: T = 2 \pi \sqrt{\frac{m}{k}} - :doc:`(doc) ` Period of torsion pendulum from rotational inertia .. math:: T = 2 \pi \sqrt{\frac{I}{\kappa}} - :doc:`(doc) ` Elastic potential energy from displacement .. math:: U = \frac{k d^{2}}{2} - :doc:`(doc) ` Potential energy from mass and height .. math:: U = m g h - :doc:`(doc) ` Pressure from force and area .. math:: p = \frac{F}{A} - :doc:`(doc) ` Reaction force equals action force .. math:: F_{21} = - F_{12} - :doc:`(doc) ` Reduced mass of a two-body system .. math:: \mu = \frac{1}{\frac{1}{m_{1}} + \frac{1}{m_{2}}} - :doc:`(doc) ` Displacement in resonant oscillations .. math:: x{\left(t \right)} = \frac{F}{2 m \omega_{0}} t \sin{\left(\omega_{0} t + \varphi \right)} - :doc:`(doc) ` Rocket thrust is rocket mass times acceleration .. math:: R v_\text{rel} = m a - :doc:`(doc) ` Rotational work is torque times angular distance .. math:: W = \tau \theta - :doc:`(doc) ` Rocket speed from mass and impulse .. math:: \Delta v = v_\text{e} \log \left( \frac{m_{0}}{m_{1}} \right) - :doc:`(doc) ` Torque via force and radial distance .. math:: \tau = r F \sin{\left(\varphi \right)} - :doc:`(doc) ` Torque via rotational inertia and angular acceleration .. math:: \tau = I \alpha - :doc:`(doc) ` Total work is change in kinetic energy .. math:: W = K{\left(t_{1} \right)} - K{\left(t_{0} \right)} - :doc:`(doc) ` Work is integral of force over distance .. math:: W = \int\limits_{x_{0}}^{x_{1}} F{\left(x \right)}\, dx - :doc:`(doc) ` :code:`laws.dynamics.damped_oscillations` .. toggle:: - :doc:`(doc) ` Energy of underdamped oscillator .. math:: E = \frac{m \omega_{0}^{2} A^{2} \exp{\left(- 2 \lambda t \right)}}{2} - :doc:`(doc) ` Quality factor via bandwidth .. math:: Q = \frac{f_\text{r}}{\Delta f} - :doc:`(doc) ` Quality factor via damping ratio .. math:: Q = \frac{1}{2 \zeta} - :doc:`(doc) ` Quality factor via energy loss .. math:: Q = \omega_\text{r} \frac{E_\text{stored}}{P_\text{loss}} - :doc:`(doc) ` :code:`laws.dynamics.deformation` .. toggle:: - :doc:`(doc) ` Bulk modulus via Young modulus and Poisson ratio .. math:: K = \frac{E}{3 \left(1 - 2 \nu\right)} - :doc:`(doc) ` Elastic energy density of bulk compression via pressure .. math:: w = \frac{p^{2}}{2 K} - :doc:`(doc) ` Elastic energy density of compression via strain .. math:: w = \frac{E e^{2}}{2} - :doc:`(doc) ` Engineering normal strain is total deformation over initial dimension .. math:: e = \frac{\Delta l}{l} - :doc:`(doc) ` Poisson ratio is transverse to axial strain ratio .. math:: \nu = - \frac{e_\text{transverse}}{e_\text{axial}} - :doc:`(doc) ` Rotational stiffness is torque applied over angle .. math:: \kappa = \frac{\tau}{\theta} - :doc:`(doc) ` Shear stress is shear modulus times strain .. math:: \tau = G \gamma - :doc:`(doc) ` Superposition of small deformations .. math:: e = e_{1} + e_{2} - :doc:`(doc) ` Tensile stress is Young's modulus times strain .. math:: \sigma = E e - :doc:`(doc) ` :code:`laws.dynamics.fields` .. toggle:: - :doc:`(doc) ` Conservative force is gradient of potential energy .. math:: {\vec F} \left( {\vec r} \right) = - \text{grad} \, U{\left({\vec r} \right)} - :doc:`(doc) ` :code:`laws.dynamics.springs` .. toggle:: - :doc:`(doc) ` Compliance of two serial springs .. math:: c = c_{1} + c_{2} - :doc:`(doc) ` Spring reaction is proportional to deformation .. math:: F = - k \Delta l - :doc:`(doc) ` Stiffness of two parallel springs .. math:: k = k_{1} + k_{2} - :doc:`(doc) ` :code:`laws.dynamics.springs.vector` .. toggle:: - :doc:`(doc) ` Spring reaction is proportional to deformation (vector) .. math:: {\vec F} = - k {\vec s} - :doc:`(doc) ` :code:`laws.dynamics.vector` .. toggle:: - :doc:`(doc) ` Acceleration from force and mass (vector) .. math:: {\vec a} = \frac{{\vec F}}{m} - :doc:`(doc) ` Force is derivative of momentum (vector) .. math:: {\vec F} \left( t \right) = \frac{d}{d t} {\vec p} \left( t \right) - :doc:`(doc) ` Instantaneous power is dot product of force and velocity .. math:: P = \left( {\vec F}, {\vec v} \right) - :doc:`(doc) ` Mechanical work from force and displacement .. math:: W = \left( {\vec F}, {\vec s} \right) - :doc:`(doc) ` Mechanical work is line integral of force .. math:: W = \int_{C} \left( {\vec F} \left( {\vec r} \right), d \vec r \right) - :doc:`(doc) ` Normal force via pressure and vector area .. math:: {\vec F}_{n} = p {\vec A} - :doc:`(doc) ` Relative acceleration from force .. math:: {\vec a}_\text{rel} = \frac{{\vec F}}{m} + {\vec a}_\text{Cor} - {\vec a}_\text{tr} - :doc:`(doc) ` Restoring torque due to twist of torsion pendulum .. math:: {\vec \tau} = - \kappa {\vec \theta} - :doc:`(doc) ` Torque is angular momentum derivative .. math:: {\vec \tau} \left( t \right) = \frac{d}{d t} {\vec L} \left( t \right) - :doc:`(doc) ` Torque of twisting force .. math:: {\vec \tau} = \left[ {\vec r}, {\vec F} \right] - :doc:`(doc) ` :code:`laws.electricity` .. toggle:: - :doc:`(doc) ` Absolute permittivity via relative permittivity .. math:: \varepsilon = \varepsilon_0 \varepsilon_\text{r} - :doc:`(doc) ` Admittance is conductance and susceptance .. math:: Y = G + i B - :doc:`(doc) ` Capacitance from charge and voltage .. math:: C = \frac{q}{V} - :doc:`(doc) ` Wave impedance from permeability and permittivity .. math:: \eta = Z_0 \sqrt{\frac{\mu_\text{r}}{\varepsilon_\text{r}}} - :doc:`(doc) ` Charge is quantized .. math:: q = N e - :doc:`(doc) ` Corona discharge current from voltage .. math:: I = A \mu V \left(V - V_{0}\right) - :doc:`(doc) ` Current is voltage over impedance .. math:: I = \frac{V}{Z} - :doc:`(doc) ` Current is voltage over resistance .. math:: I = \frac{V}{R} - :doc:`(doc) ` Electric charge is constant in isolated system .. math:: q_{1} = q_{0} - :doc:`(doc) ` Electric dipole moment is charge times distance .. math:: p = q d - :doc:`(doc) ` Electric displacement is permittivity times electric field .. math:: D = \varepsilon E - :doc:`(doc) ` Electric field due to dipole on the dipole axis .. math:: E = \frac{1}{2 \pi \varepsilon_0} \frac{p}{d^{3}} - :doc:`(doc) ` Electric field due to point charge .. math:: E = \frac{1}{4 \pi \varepsilon_0} \frac{q}{d^{2}} - :doc:`(doc) ` Electric field is force over test charge .. math:: E = \frac{F}{q_{0}} - :doc:`(doc) ` Electric field of uniformly charged plane .. math:: E = \frac{\sigma}{2 \varepsilon_0} - :doc:`(doc) ` Electric field outside charged sphere .. math:: E = \frac{q}{4 \pi \varepsilon_0 d^{2}} - :doc:`(doc) ` Electric flux through closed surface in linear material .. math:: \Phi_{\vec E} = \frac{q_\text{free}}{\varepsilon} - :doc:`(doc) ` Electric flux through closed surface via total charge .. math:: \Phi_{\vec E} = \frac{q}{\varepsilon_0} - :doc:`(doc) ` Electric field in gas gap between two electrodes .. math:: E = \frac{3 \sqrt{\frac{x}{d}} \frac{V}{d}}{2} - :doc:`(doc) ` Electromotive force induced in moving contour .. math:: \mathcal{E} = - N \frac{d}{d t} \Phi_{\vec B}{\left(t \right)} - :doc:`(doc) ` Electromotive force induced in rotating rod .. math:: \mathcal{E} = \frac{B \omega l^{2}}{2} - :doc:`(doc) ` Electromotive force induced in rotating coil .. math:: \mathcal{E} = - N B A \omega \sin{\left(\omega t \right)} - :doc:`(doc) ` Electrostatic force via charges and distance .. math:: F = \frac{1}{4 \pi \varepsilon_0} \frac{q_{1} q_{2}}{d^{2}} - :doc:`(doc) ` Electrostatic potential due to point charge .. math:: U_{\vec E} = \frac{q}{4 \pi \varepsilon d} - :doc:`(doc) ` Electrostatic potential energy of two charges via distance .. math:: U_{\vec E} = \frac{q_{1} q_{2}}{4 \pi \varepsilon d} - :doc:`(doc) ` Electrostatic potential is work to bring from reference point over charge .. math:: U_{\vec E} = \frac{W}{q} - :doc:`(doc) ` Energy density via permittivity and electric field .. math:: w = \frac{\varepsilon E^{2}}{2} - :doc:`(doc) ` Energy of magnetic field of coil .. math:: E = \frac{\mu_0 \mu_\text{r} H^{2} V}{2} - :doc:`(doc) ` Energy via constant power and time .. math:: E = P t - :doc:`(doc) ` Force between parallel wires .. math:: F = \frac{\mu I_{1} I_{2} l}{2 \pi d} - :doc:`(doc) ` Inductance is magnetic flux over current .. math:: L = \frac{\Phi_{\vec B}}{I} - :doc:`(doc) ` Inductance is proportional to turn count .. math:: L = \frac{\mu N^{2} A}{l} - :doc:`(doc) ` Inductance via number of turns and coil volume .. math:: L = \mu n^{2} V - :doc:`(doc) ` Instantaneous energy of magnetic field .. math:: E = \frac{L I_\text{max}^{2}}{2} \cos^{2}{\left(\omega t + \varphi \right)} - :doc:`(doc) ` Magnetic field due to current loop along axis .. math:: B = \frac{\mu_0 I r^{2}}{2 \left(d^{2} + r^{2}\right)^{\frac{3}{2}}} - :doc:`(doc) ` Magnetic field due to finite coil along axis .. math:: B = \frac{\mu_0 I N}{2 \ell} \left(\cos{\left(\varphi_{1} \right)} + \cos{\left(\varphi_{2} \right)}\right) - :doc:`(doc) ` Magnetic field due to infinite wire .. math:: B = \frac{\mu I}{2 \pi r} - :doc:`(doc) ` Magnetic field of coil .. math:: B = \frac{\mu_0 I N}{l} - :doc:`(doc) ` Magnetic flux from magnetic flux density and area .. math:: \Phi_{\vec B} = B A \cos{\left(\varphi \right)} - :doc:`(doc) ` Magnetic flux density from magnetic field strength .. math:: B = \mu H - :doc:`(doc) ` Magnetic flux density of linear conductor of finite length .. math:: B = \frac{\mu I \left(\cos{\left(\varphi_{1} \right)} + \cos{\left(\varphi_{2} \right)}\right)}{4 \pi d} - :doc:`(doc) ` Magnetic moment via current and contour area .. math:: m = I A - :doc:`(doc) ` Period of rotation of charged particle in magnetic field .. math:: T = \frac{2 \pi m}{q B} - :doc:`(doc) ` Power factor is real power over apparent power .. math:: \mathrm{pf} = \frac{P}{S} - :doc:`(doc) ` Power via current and resistance .. math:: P = I^{2} R - :doc:`(doc) ` Power via voltage and current .. math:: P = I V - :doc:`(doc) ` Power via voltage and resistance .. math:: P = \frac{V^{2}}{R} - :doc:`(doc) ` Radius of curvature of charged particle in magnetic field .. math:: r = \frac{m v}{q B} - :doc:`(doc) ` Resistance via resistivity and dimensions .. math:: R = \frac{\rho l}{A} - :doc:`(doc) ` Self-induced electromotive force via time derivative of current .. math:: \mathcal{E}{\left(t \right)} = - L \frac{d}{d t} I{\left(t \right)} - :doc:`(doc) ` Voltage is electric field times distance .. math:: V = E d - :doc:`(doc) ` Voltage is line integral of electric field .. math:: V = - \int\limits_{s_{0}}^{s_{1}} E_{s}{\left(s \right)}\, ds - :doc:`(doc) ` :code:`laws.electricity.circuits` .. toggle:: - :doc:`(doc) ` Admittance in parallel connection .. math:: Y = \sum_i {Y}_{i} - :doc:`(doc) ` Capacitance in parallel connection .. math:: C = \sum_i {C}_{i} - :doc:`(doc) ` Capacitance is proportional to plate area .. math:: C = \frac{\varepsilon A}{d} - :doc:`(doc) ` Capacitance of spherical capacitor .. math:: C = \frac{4 \pi \varepsilon r_\text{in} r_\text{out}}{r_\text{out} - r_\text{in}} - :doc:`(doc) ` Capacitor impedance from capacitance and frequency .. math:: Z = - \frac{i}{\omega C} - :doc:`(doc) ` Capacitor impedance from capacitor reactance .. math:: Z = - i X - :doc:`(doc) ` Coil impedance from inductive reactance .. math:: Z = i X - :doc:`(doc) ` Coil impedance via inductance and frequency .. math:: Z = i \omega L - :doc:`(doc) ` Energy stored in capacitor via capacitance and voltage .. math:: W = \frac{C V^{2}}{2} - :doc:`(doc) ` Energy stored in inductor via inductance and current .. math:: W = \frac{L I^{2}}{2} - :doc:`(doc) ` Impedance in serial connection .. math:: Z = \sum_i {Z}_{i} - :doc:`(doc) ` Impedance module of serial resistor-coil-capacitor circuit .. math:: |Z| = \sqrt{R^{2} + \left(X_\text{L} - X_\text{C}\right)^{2}} - :doc:`(doc) ` Inductance in serial connection .. math:: L = \sum_i {L}_{i} - :doc:`(doc) ` Input impedance of thin film resistor .. math:: Z = \frac{R}{1 + \frac{i \omega R C}{3}} - :doc:`(doc) ` Oscillation period of inductor-capacitor network .. math:: T = 2 \pi \sqrt{L C} - :doc:`(doc) ` Resistivity of serial resistors .. math:: R = \sum_i {R}_{i} - :doc:`(doc) ` Sum of currents through junction is zero .. math:: \sum_k {I}_{k} = 0 - :doc:`(doc) ` Sum of voltages in loop is zero .. math:: \sum_i {V}_{i} = 0 - :doc:`(doc) ` Time constant of resistor-capacitor circuit .. math:: \tau = R C - :doc:`(doc) ` Capacitance of p-n varactor junction .. math:: C = \frac{C_{0}}{\left(1 - \frac{V}{V_{0}}\right)^{y}} - :doc:`(doc) ` Voltage across charging capacitor in serial resistor-capacitor circuit .. math:: V = V_{0} \left(1 - \exp{\left(- \frac{t}{\tau} \right)}\right) - :doc:`(doc) ` :code:`laws.electricity.circuits.couplers` .. toggle:: - :doc:`(doc) ` Attenuation of three link microwave attenuator .. math:: A = \exp{\left(\operatorname{acosh}{\left(1 + \frac{R_{1}}{R_{2}} \right)} \right)} - :doc:`(doc) ` Admittance of rectangular loop coupler .. math:: \begin{pmatrix} Y_{1} \\ Y_{2} \\ Y_{3} \\ Y_{4} \end{pmatrix} = \begin{pmatrix} \frac{Y_{0}}{\sqrt{k}} \\ Y_{0} \sqrt{\frac{k + 1}{k}} \\ Y_{0} \sqrt{\frac{k + 1}{k}} \\ \frac{Y_{0}}{\sqrt{k}} \end{pmatrix} - :doc:`(doc) ` Total gain of transistor amplifier .. math:: \text{gain} = \text{gain}_\text{i} \text{gain}_\text{t} \text{gain}_\text{o} - :doc:`(doc) ` Impedance of Wilkinson microstrip divider .. math:: \begin{pmatrix} Z_{1} \\ Z_{2} \\ Z_{3} \\ Z_{4} \end{pmatrix} = \begin{pmatrix} Z_{0} \sqrt{k \left(1 + k^{2}\right)} \\ Z_{0} \sqrt{\frac{1 + k^{2}}{k^{3}}} \\ Z_{0} \sqrt{k} \\ \frac{Z_{0}}{\sqrt{k}} \end{pmatrix} - :doc:`(doc) ` Section length of multistage transformer .. math:: l = \frac{\lambda_{1} \lambda_{2}}{2 \left(\lambda_{1} + \lambda_{2}\right)} - :doc:`(doc) ` Relative operating bandwidth of quarter-wave transformer .. math:: b = 2 - \frac{4}{\pi} \operatorname{acos}{\left(\frac{2 \Gamma \sqrt{R_\text{L} Z_\text{S}}}{\sqrt{1 - \Gamma^{2}} \left|{R_\text{L} - Z_\text{S}}\right|} \right)} - :doc:`(doc) ` Resistor resistance in Wilkinson divider .. math:: R = \frac{R_{0} \left(1 + k^{2}\right)}{k} - :doc:`(doc) ` Transient attenuation of separate loop coupler with cascade connection .. math:: A_{0} = 20 \log_{10} \left( \sin{\left(N \operatorname{asin}{\left(10^{\frac{A}{20}} \right)} \right)} \right) - :doc:`(doc) ` Wave impedance of even mode of Lange coupler .. math:: \eta_\text{e} = \frac{\eta_\text{o} \left(C + \sqrt{C^{2} + \left(1 - C^{2}\right) \left(N - 1\right)^{2}}\right)}{\left(N - 1\right) \left(1 - C\right)} - :doc:`(doc) ` Wave impedance of odd mode of Lange coupler .. math:: \eta_\text{o} = Z_\text{S} \sqrt{\frac{1 - C}{1 + C}} \frac{\left(N - 1\right) \left(1 + \sqrt{C^{2} + \left(1 - C^{2}\right) \left(N - 1\right)^{2}}\right)}{C + \sqrt{C^{2} + \left(1 - C^{2}\right) \left(N - 1\right)^{2}} + \left(N - 1\right) \left(1 - C\right)} - :doc:`(doc) ` Wave impedance of Lange coupler .. math:: \eta = \sqrt{\frac{\eta_\text{o} \eta_\text{e} \left(\eta_\text{o} + \eta_\text{e}\right)^{2}}{\left(\eta_\text{o} + \eta_\text{e} \left(N - 1\right)\right) \left(\eta_\text{e} + \eta_\text{o} \left(N - 1\right)\right)}} - :doc:`(doc) ` :code:`laws.electricity.circuits.diodes` .. toggle:: - :doc:`(doc) ` Current from voltage and diode constant in vacuum diode .. math:: I = g U_\text{a}^{\frac{3}{2}} - :doc:`(doc) ` Current from voltage and triode constant in vacuum triode .. math:: I = g \left(U_\text{a} + \text{gain}_{V} U_\text{g}\right)^{\frac{3}{2}} - :doc:`(doc) ` Diode constant for parallel-plane vacuum diode .. math:: g = \frac{4 \varepsilon_0}{9} \sqrt{\frac{2 e}{m_\text{e}}} \frac{A}{d^{2}} - :doc:`(doc) ` Diode constant of cylindrical diode .. math:: g = \frac{\frac{4 \varepsilon_0}{9} \sqrt{\frac{2 e}{m_\text{e}}} A_\text{a}}{r_\text{a}^{2} \left(1 - \frac{r_\text{c}}{r_\text{a}}\right)^{2}} - :doc:`(doc) ` Direct permeability coefficient of triode with flat electrodes .. math:: D = \frac{C_{1} d_{0}}{d C_{2}} - :doc:`(doc) ` Internal resistance of vacuum diode .. math:: R = \frac{2}{3 g \sqrt{V}} - :doc:`(doc) ` Limit operating frequency of vacuum diode .. math:: f = \frac{\sqrt{\frac{2 e V}{m_\text{e}}}}{6 d} - :doc:`(doc) ` Charge density in diode .. math:: \rho = \frac{\frac{4 \varepsilon_0}{9} V}{d^{2}} - :doc:`(doc) ` Steepness of volt-ampere characteristic of vacuum diode .. math:: S = \frac{3 g}{2} \sqrt{V} - :doc:`(doc) ` Voltage of equivalent diode for pentode .. math:: V = \frac{V_{1} + V_{2} D_{1} + V_{3} D_{1} D_{2} + U_\text{a} D_{1} D_{2} D_{3}}{1 + D_{1} \left(\frac{d_\text{a}}{d_{1}}\right)^{\frac{4}{3}}} - :doc:`(doc) ` Equivalent diode voltage for tetrode .. math:: V = \frac{V_{1} + V_{2} D_{1} + U_\text{a} D_{1} D_{2}}{1 + D_{1} \left(\frac{d_\text{a}}{d_{1}}\right)^{\frac{4}{3}}} - :doc:`(doc) ` Equivalent diode voltage for triode .. math:: V = \frac{U_\text{g} + \frac{U_\text{a}}{\text{gain}_{V}}}{1 + \frac{\left(\frac{d_\text{a}}{d_\text{g}}\right)^{\frac{4}{3}}}{\text{gain}_{V}}} - :doc:`(doc) ` :code:`laws.electricity.circuits.filters` .. toggle:: - :doc:`(doc) ` Transmission coefficient approximation of low-pass filter .. math:: H = \frac{1}{1 + e^{2} F^{2}} - :doc:`(doc) ` Band pass Chebyshev filter order from distortion and frequency .. math:: N = \frac{\operatorname{acosh}{\left(\frac{e}{e_{1}} \right)}}{\operatorname{acosh}{\left(\frac{f_{1}^{2} - f_{0}^{2}}{\Delta f f_{1}} \right)}} - :doc:`(doc) ` Butterworth filter order from distortion and frequency .. math:: N = \frac{\log \left( \frac{e_{1}}{e} \right)}{\log \left( \frac{f_{1}}{f_{0}} \right)} - :doc:`(doc) ` Filter order from distortion and frequency .. math:: F = \frac{e_{1}}{e} - :doc:`(doc) ` High pass Chebyshev filter from distortion and frequency .. math:: N = \frac{\operatorname{acosh}{\left(\frac{e_{1}}{e} \right)}}{\operatorname{acosh}{\left(\frac{f_{0}}{f_{1}} \right)}} - :doc:`(doc) ` Low-pass Chebyshev filter order from distortion and frequencies .. math:: N = \frac{\operatorname{acos}{\left(\frac{e_{1}}{e} \right)}}{\operatorname{acos}{\left(\frac{f_{1}}{f_{0}} \right)}} - :doc:`(doc) ` :code:`laws.electricity.circuits.resonators` .. toggle:: - :doc:`(doc) ` Coupling parameter of resonator from quality factor .. math:: g = \frac{Q_{0}}{Q_\text{e}} - :doc:`(doc) ` Coupling parameter of resonator from resistance .. math:: g = \frac{R_{0}}{R_\text{L}} - :doc:`(doc) ` Instantaneous energy of resonator .. math:: E = E_{0} \exp{\left(- \frac{\omega t}{Q} \right)} - :doc:`(doc) ` Quality factor of loaded resonator from circuit parameters .. math:: Q_{1} = \frac{R_\text{L} R_{0}}{\omega L \left(R_\text{L} + R_{0}\right)} - :doc:`(doc) ` Quality resonator of loaded resonator from quality factors .. math:: \frac{1}{Q_{1}} = \frac{1}{Q_{0}} + \frac{1}{Q_\text{e}} - :doc:`(doc) ` Quality factor of resonator .. math:: Q = \frac{R}{\omega L} - :doc:`(doc) ` Quality factor of empty rectangular resonator for traverse electric waves .. math:: Q = \frac{\omega \mu l_{3} l_{2} l_{1} \left(l_{2}^{2} + l_{1}^{2}\right)}{2 R_\text{s} \left(l_{2}^{3} \left(l_{1} + 2 l_{3}\right) + l_{1}^{3} \left(l_{2} + 2 l_{3}\right)\right)} - :doc:`(doc) ` Quality factor of filled rectangular resonator .. math:: Q_{1} = \frac{1}{\frac{1}{Q_{0}} + \tan \delta} - :doc:`(doc) ` Resonant frequency of rectangular resonator .. math:: f_\text{r} = \frac{c}{2 \sqrt{\varepsilon_\text{r} \mu_\text{r}}} \sqrt{\left(\frac{m}{l_{1}}\right)^{2} + \left(\frac{n}{l_{2}}\right)^{2} + \left(\frac{p}{l_{3}}\right)^{2}} - :doc:`(doc) ` Resonant frequency of ring resonator .. math:: f = \frac{N c}{l \sqrt{\varepsilon_\text{r}}} - :doc:`(doc) ` :code:`laws.electricity.circuits.transmission_lines` .. toggle:: - :doc:`(doc) ` Standing wave ratio from reflection coefficient .. math:: \text{SWR} = \frac{1 + \left|{\Gamma}\right|}{1 - \left|{\Gamma}\right|} - :doc:`(doc) ` Standing wave ratio from voltage .. math:: \text{SWR} = \frac{\min{|V|}}{\max{|V|}} - :doc:`(doc) ` Hybrid parameters matrix equation .. math:: \begin{pmatrix} V_\text{i} \\ I_\text{o} \end{pmatrix} = \begin{pmatrix} H_\text{ii} & H_\text{io} \\ H_\text{oi} & H_\text{oo} \end{pmatrix} \begin{pmatrix} I_\text{i} \\ V_\text{o} \end{pmatrix} - :doc:`(doc) ` Impedances of π-type circuit of transmission line .. math:: \begin{pmatrix} Z_{1} \\ Z_{2} \\ Z_{3} \end{pmatrix} = \begin{pmatrix} Z_\text{S} \coth{\left(\frac{l \gamma}{2} \right)} \\ Z_\text{S} \coth{\left(\frac{l \gamma}{2} \right)} \\ Z_\text{S} \sinh{\left(l \gamma \right)} \end{pmatrix} - :doc:`(doc) ` Impedances of T-type circuit of transmission line .. math:: \begin{pmatrix} Z_{1} \\ Z_{2} \\ Z_{3} \end{pmatrix} = \begin{pmatrix} Z_\text{S} \tanh{\left(\frac{l \gamma}{2} \right)} \\ Z_\text{S} \tanh{\left(\frac{l \gamma}{2} \right)} \\ \frac{Z_\text{S}}{\sinh{\left(l \gamma \right)}} \end{pmatrix} - :doc:`(doc) ` Input impedance from transmission matrix .. math:: Z_\text{in} = \frac{A Z_\text{L} + B}{C Z_\text{L} + D} - :doc:`(doc) ` Input impedance of lossless transmission line .. math:: Z_\text{in} = \frac{Z_\text{S} \left(Z_\text{L} + i Z_\text{S} \tan{\left(\beta l \right)}\right)}{Z_\text{S} + i Z_\text{L} \tan{\left(\beta l \right)}} - :doc:`(doc) ` Input impedance of lossy transmission line .. math:: Z_\text{in} = \frac{\cosh{\left(\gamma l \right)} Z_\text{L} + Z_\text{S} \sinh{\left(\gamma l \right)}}{\frac{Z_\text{L} \sinh{\left(\gamma l \right)}}{Z_\text{S}} + \cosh{\left(\gamma l \right)}} - :doc:`(doc) ` Reflection coefficient from ratio of average power to incident power .. math:: \frac{\langle P \rangle}{P_\text{incident}} = 1 - \left|{\Gamma}\right|^{2} - :doc:`(doc) ` Standing wave ratio from ratio of average power to incident power .. math:: \frac{\langle P \rangle}{P_\text{incident}} = \frac{4 \text{SWR}}{\left(\text{SWR} + 1\right)^{2}} - :doc:`(doc) ` Reflection coefficient from load and surge impedance .. math:: \Gamma = \frac{Z_\text{L} - Z_\text{S}}{Z_\text{L} + Z_\text{S}} - :doc:`(doc) ` Scattering matrix equation .. math:: \begin{pmatrix} b_\text{i} \\ b_\text{o} \end{pmatrix} = \begin{pmatrix} S_\text{ii} & S_\text{io} \\ S_\text{oi} & S_\text{oo} \end{pmatrix} \begin{pmatrix} a_\text{i} \\ a_\text{o} \end{pmatrix} - :doc:`(doc) ` Scattering matrix to transmission matrix .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} \frac{\left(1 + S_\text{ii}\right) \left(1 - S_\text{oo}\right) + S_\text{io} S_\text{oi}}{2 S_\text{oi}} & \frac{Z_\text{S} \left(\left(1 + S_\text{ii}\right) \left(1 + S_\text{oo}\right) - S_\text{io} S_\text{oi}\right)}{2 S_\text{oi}} \\ \frac{\left(1 - S_\text{ii}\right) \left(1 - S_\text{oo}\right) - S_\text{io} S_\text{oi}}{Z_\text{S}} \frac{1}{2 S_\text{oi}} & \frac{\left(1 - S_\text{ii}\right) \left(1 + S_\text{oo}\right) + S_\text{io} S_\text{oi}}{2 S_\text{oi}} \end{pmatrix} - :doc:`(doc) ` Admittance matrix equation .. math:: \begin{pmatrix} I_\text{i} \\ I_\text{o} \end{pmatrix} = \begin{pmatrix} Y_\text{ii} & Y_\text{io} \\ Y_\text{oi} & Y_\text{oo} \end{pmatrix} \begin{pmatrix} V_\text{i} \\ V_\text{o} \end{pmatrix} - :doc:`(doc) ` Impedance matrix equation .. math:: \begin{pmatrix} V_\text{i} \\ V_\text{o} \end{pmatrix} = \begin{pmatrix} Z_\text{ii} & Z_\text{io} \\ Z_\text{oi} & Z_\text{oo} \end{pmatrix} \begin{pmatrix} I_\text{i} \\ I_\text{o} \end{pmatrix} - :doc:`(doc) ` Transmission matrix equation .. math:: \begin{pmatrix} V_\text{i} \\ I_\text{i} \end{pmatrix} = \begin{pmatrix} A & B \\ C & D \end{pmatrix} \begin{pmatrix} V_\text{o} \\ I_\text{o} \end{pmatrix} - :doc:`(doc) ` Transmission matrix for parallel load in line .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} 1 & 0 \\ \frac{1}{Z_\text{L}} & 1 \end{pmatrix} - :doc:`(doc) ` Transmission matrix for serial load in line .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} 1 & Z_\text{L} \\ 0 & 1 \end{pmatrix} - :doc:`(doc) ` Transmission matrix of lossless transmission line .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} \cos{\left(\beta l \right)} & i Z_\text{S} \sin{\left(\beta l \right)} \\ \frac{i}{Z_\text{S}} \sin{\left(\beta l \right)} & \cos{\left(\beta l \right)} \end{pmatrix} - :doc:`(doc) ` Transmission matrix of lossy transmission line .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} \cosh{\left(l \gamma \right)} & Z_\text{S} \sinh{\left(l \gamma \right)} \\ \frac{\sinh{\left(l \gamma \right)}}{Z_\text{S}} & \cosh{\left(l \gamma \right)} \end{pmatrix} - :doc:`(doc) ` Transmission matrix of π-type matrix .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} 1 + \frac{Z_{3}}{Z_{2}} & Z_{3} \\ \frac{1}{Z_{1}} + \frac{1}{Z_{2}} + \frac{Z_{3}}{Z_{1} Z_{2}} & 1 + \frac{Z_{3}}{Z_{1}} \end{pmatrix} - :doc:`(doc) ` Transmission matrix of T-type circuit .. math:: \begin{pmatrix} A & B \\ C & D \end{pmatrix} = \begin{pmatrix} 1 + \frac{Z_{1}}{Z_{3}} & Z_{1} + Z_{2} + \frac{Z_{1} Z_{2}}{Z_{3}} \\ \frac{1}{Z_{3}} & 1 + \frac{Z_{2}}{Z_{3}} \end{pmatrix} - :doc:`(doc) ` Surge impedance of microstrip line when effective width is greater than substrate thickness .. math:: Z_\text{S} = \frac{Z_0}{\sqrt{\varepsilon_\text{eff}}} \frac{1}{\frac{w_\text{eff}}{h} + 1.393 + 0.667 \log \left( \frac{w_\text{eff}}{h} + 1.444 \right)} - :doc:`(doc) ` Surge impedance of microstrip line when effective width is less than substrate thickness .. math:: Z_\text{S} = \frac{Z_0}{\sqrt{\varepsilon_\text{eff}}} \log \left( \frac{8 h}{w_\text{eff}} + \frac{w_\text{eff}}{4 h} \right) - :doc:`(doc) ` :code:`laws.electricity.circuits.transmission_lines.coplanar_lines` .. toggle:: - :doc:`(doc) ` Effective permittivity of coplanar transmission line when distance is greater than thickness .. math:: \varepsilon_\text{eff} = 1 + \frac{\varepsilon_\text{r} - 1}{2} \frac{\log \left( \frac{2 \left(1 + \left(1 - \left(\frac{l}{d}\right)^{2}\right)^{\frac{1}{4}}\right)}{1 - \left(1 - \left(\frac{l}{d}\right)^{2}\right)^{\frac{1}{4}}} \right)}{\log \left( \frac{2 \left(1 + \left(1 - \left(\frac{\sinh{\left(\frac{\pi l}{4 h} \right)}}{\sinh{\left(\frac{\pi d}{4 h} \right)}}\right)^{2}\right)^{\frac{1}{4}}\right)}{1 - \left(1 - \left(\frac{\sinh{\left(\frac{\pi l}{4 h} \right)}}{\sinh{\left(\frac{\pi d}{4 h} \right)}}\right)^{2}\right)^{\frac{1}{4}}} \right)} - :doc:`(doc) ` Effective permittivity of coplanar transmission line when distance is less than thickness .. math:: \varepsilon_\text{eff} = \frac{1 + \varepsilon_\text{r}}{2} - :doc:`(doc) ` Wave impedance of coplanar line when hyperbolic sine ratio squared is between :math:`0` and :math:`\frac{1}{2}` .. math:: \eta = \frac{R_0}{\sqrt{\varepsilon_\text{eff}}} \log \left( \frac{2 \left(1 + \left(1 - \left(\frac{l}{d}\right)^{2}\right)^{\frac{1}{4}}\right)}{1 - \left(1 - \left(\frac{l}{d}\right)^{2}\right)^{\frac{1}{4}}} \right) - :doc:`(doc) ` Wave impedance of coplanar line when length to distance ratio squared is between :math:`\frac{1}{2}` and :math:`1` .. math:: \eta = \frac{R_0}{\sqrt{\varepsilon_\text{eff}}} \frac{1}{\log \left( \frac{2 \left(1 + \sqrt{\frac{l}{d}}\right)}{1 - \sqrt{\frac{l}{d}}} \right)} - :doc:`(doc) ` :code:`laws.electricity.circuits.transmission_lines.microstrip_lines` .. toggle:: - :doc:`(doc) ` Attenuation coefficient in dielectric substate of microstrip line .. math:: \alpha = 27.3 \frac{\varepsilon_\text{r}}{\sqrt{\varepsilon_\text{eff}}} \frac{\varepsilon_\text{eff} - 1}{\varepsilon_\text{r} - 1} \frac{\tan \delta}{\lambda} - :doc:`(doc) ` Attenuation coefficient in metal of microstrip line when width is greater than thickness .. math:: \alpha = \frac{a R_\text{s} Z_\text{S} \varepsilon_\text{eff}}{h} \left(\frac{w_\text{eff}}{h} + \frac{0.667 \frac{w_\text{eff}}{h}}{\frac{w_\text{eff}}{h} + 1.444}\right) \left(1 + \frac{1 - \frac{1.25}{\pi} \frac{t}{h} + \frac{1.25}{\pi} \log \left( \frac{2 h}{t} \right)}{\frac{w_\text{eff}}{h}}\right) - :doc:`(doc) ` Attenuation coefficient in microstrip metal when thickness is greater than width times :math:`2 \pi` .. math:: \alpha = \frac{1.38 R_\text{s}}{h Z_\text{S}} \frac{32 - \left(\frac{w_\text{eff}}{h}\right)^{2}}{32 + \left(\frac{w_\text{eff}}{h}\right)^{2}} \left(1 + \frac{h}{w_\text{eff}} \left(1 + \frac{1.25}{\pi} \frac{t}{w} + \frac{1.25}{\pi} \log \left( \frac{4 \pi w}{t} \right)\right)\right) - :doc:`(doc) ` Attenuation coefficient in microstrip metal when thickness is less than width times :math:`2 \pi` .. math:: \alpha = \frac{1.38 R_\text{s}}{h Z_\text{S}} \frac{32 - \left(\frac{w_\text{eff}}{h}\right)^{2}}{32 + \left(\frac{w_\text{eff}}{h}\right)^{2}} \left(1 + \frac{h}{w_\text{eff}} \left(1 - \frac{1.25}{\pi} \frac{t}{h} + \frac{1.25}{\pi} \log \left( 2 \frac{h}{t} \right)\right)\right) - :doc:`(doc) ` Effective permittivity of microstrip line when width is greater than thickness .. math:: \varepsilon_\text{eff} = \frac{1 + \varepsilon_\text{r}}{2} + \frac{\varepsilon_\text{r} - 1}{2} \frac{1}{\sqrt{1 + \frac{12 h}{w}}} - \frac{\varepsilon_\text{r} - 1}{4.6} \frac{t}{h} \sqrt{\frac{h}{w}} - :doc:`(doc) ` Effective permittivity of microstrip line when width is less than thickness .. math:: \varepsilon_\text{eff} = \frac{1 + \varepsilon_\text{r}}{2} + \frac{\varepsilon_\text{r} - 1}{2} \left(\frac{1}{\sqrt{1 + \frac{12 h}{w}}} + 0.04 \left(1 - \frac{w}{h}\right)^{2}\right) - \frac{\varepsilon_\text{r} - 1}{4.6} \frac{t}{h} \sqrt{\frac{h}{w}} - :doc:`(doc) ` Effective permittivity of microstrip line from frequency .. math:: \varepsilon_\text{eff} = \left(\frac{\sqrt{\varepsilon_\text{r}} - \sqrt{\varepsilon_{\text{eff}, 0}}}{1 + \frac{4}{\left(4 h f \left(1 + 2 \log \left( 1 + \frac{w}{h} \right)\right)^{2} \sqrt{\varepsilon_\text{r} - 1} \frac{1}{2 c}\right)^{\frac{3}{2}}}} + \sqrt{\varepsilon_{\text{eff}, 0}}\right)^{2} - :doc:`(doc) ` Effective width of microstrip line when width is greater than thickness .. math:: \frac{w_\text{eff}}{h} = \frac{w}{h} + \frac{1.25}{\pi} \frac{t}{h} \left(1 + \log \left( 2 \frac{h}{t} \right)\right) - :doc:`(doc) ` Effective width of microstrip line when width is less than thickness .. math:: \frac{w_\text{eff}}{h} = \frac{w}{h} + \frac{1.25}{\pi} \frac{t}{h} \left(1 + \log \left( 4 \pi \frac{w}{t} \right)\right) - :doc:`(doc) ` Inductance of microstrip line strip .. math:: L = L_0 l \left(\log \left( \frac{l}{w + t} \right) + 1.193 + \frac{0.2235}{\frac{l}{w + t}}\right) - :doc:`(doc) ` Resistance of microstrip line .. math:: R = \left(1.4 + 0.217 \log \left( \frac{w}{5 t} \right)\right) \frac{R_\text{s} l}{2 \left(w + t\right)} - :doc:`(doc) ` Short circuit inductance of microstrip line .. math:: L = \frac{\mu_0}{2 \pi} \left(h \log \left( \frac{h + \sqrt{r^{2} + h^{2}}}{r} \right) + 1.5 \left(r - \sqrt{r^{2} + h^{2}}\right)\right) - :doc:`(doc) ` Surge impedance of microstrip line from frequency .. math:: Z_\text{S} = Z_{\text{S}, 0} \sqrt{\frac{\varepsilon_{\text{eff}, 0}}{\varepsilon_\text{eff}}} \frac{\varepsilon_\text{eff} - 1}{\varepsilon_{\text{eff}, 0} - 1} - :doc:`(doc) ` :code:`laws.electricity.circuits.waveguides` .. toggle:: - :doc:`(doc) ` Attenuation coefficient in dielectric .. math:: \alpha = \frac{\omega \sqrt{\varepsilon \mu} \tan \delta}{2} - :doc:`(doc) ` Attenuation coefficient in dielectric in rectangular waveguide .. math:: \alpha = \frac{\pi}{\lambda} \frac{\eta}{\eta_{0}} \tan \delta - :doc:`(doc) ` Attenuation coefficient in metal .. math:: \alpha = \frac{\sqrt{\frac{\varepsilon_\text{r}}{\mu_\text{r}}} \left(\frac{R_\text{i}}{d_\text{i}} + \frac{R_\text{o}}{d_\text{o}}\right)}{\pi R_0 \log \left( \frac{d_\text{o}}{d_\text{i}} \right)} - :doc:`(doc) ` Attenuation coefficient in metal in rectangular waveguide for transverse electric waves .. math:: \alpha = \frac{2 \frac{R_\text{s}}{R}}{a \sqrt{1 - \left(\frac{\lambda}{2 \lambda_\text{c}}\right)^{2}}} \left(\left(1 + \frac{a}{b}\right) \left(\frac{\lambda}{2 \lambda_\text{c}}\right)^{2} + \frac{\left(1 - \left(\frac{\lambda}{2 \lambda_\text{c}}\right)^{2}\right) \frac{a}{b} \left(\frac{a}{b} n^{2} + m^{2}\right)}{\left(\frac{a}{b} n\right)^{2} + m^{2}}\right) - :doc:`(doc) ` Attenuation coefficient in metal in rectangular waveguide for transverse magnetic waves .. math:: \alpha = \frac{2 \frac{R_\text{s}}{R} \left(n^{2} \left(\frac{a}{b}\right)^{3} + m^{2}\right)}{a \sqrt{1 - \left(\frac{\lambda}{2 \lambda_\text{c}}\right)^{2}} \left(n^{2} \left(\frac{a}{b}\right)^{2} + m^{2}\right)} - :doc:`(doc) ` Wave impedance in rectangular waveguide for transverse electric waves .. math:: \eta = \frac{\eta_{0}}{\sqrt{1 - \left(\frac{\lambda}{\lambda_\text{c}}\right)^{2}}} - :doc:`(doc) ` Characteristic resistance of rectangular waveguide for transverse magnetic waves .. math:: \eta = \eta_{0} \sqrt{1 - \left(\frac{\lambda}{\lambda_\text{c}}\right)^{2}} - :doc:`(doc) ` Critical wavelength in rectangular waveguide .. math:: \lambda_\text{c} = \frac{2}{\sqrt{\left(\frac{m}{a}\right)^{2} + \left(\frac{n}{b}\right)^{2}}} - :doc:`(doc) ` Group speed of wave in rectangular waveguide .. math:: v_\text{g} = \frac{c \sqrt{1 - \left(\frac{\lambda}{\lambda_\text{c}}\right)^{2}}}{\sqrt{\varepsilon_\text{r} \mu_\text{r}}} - :doc:`(doc) ` Maximum electric field strength of main wave in rectangular waveguide .. math:: E = \frac{2 Z_0 a H}{\lambda \sqrt{\varepsilon_\text{r}}} - :doc:`(doc) ` Maximum voltage in coaxial line .. math:: V = \frac{E d_\text{o} \log \left( \frac{d_\text{o}}{d_\text{i}} \right)}{2} - :doc:`(doc) ` Phase speed of wave in rectangular waveguide .. math:: v = \frac{c}{\sqrt{\varepsilon_\text{r} \mu_\text{r} \left(1 - \left(\frac{\lambda}{\lambda_\text{c}}\right)^{2}\right)}} - :doc:`(doc) ` Power carried by coaxial waveguide .. math:: P = \frac{V^{2}}{Z_0} \sqrt{\frac{\varepsilon_\text{r}}{\mu_\text{r} \log \left( \frac{d_\text{o}}{d_\text{i}} \right)}} - :doc:`(doc) ` Power carried by main wave of rectangular waveguide .. math:: P = \frac{a b \sqrt{1 - \left(\frac{\lambda}{2 a}\right)^{2}} E^{2}}{4 R} - :doc:`(doc) ` Specific capacitance of coaxial waveguide .. math:: C = \frac{2 \pi \varepsilon}{\log \left( \frac{r_\text{o}}{r_\text{i}} \right)} - :doc:`(doc) ` Specific conductivity of coaxial waveguide .. math:: G = \omega C \tan \delta - :doc:`(doc) ` Specific inductance of coaxial waveguide .. math:: L = \frac{\mu}{2 \pi} \log \left( \frac{r_\text{o}}{r_\text{i}} \right) - :doc:`(doc) ` Specific resistance of coaxial waveguide .. math:: R = \frac{\sqrt{\frac{\omega \mu}{2 G}}}{2 \pi} \left(\frac{1}{r_\text{i}} - \frac{1}{r_\text{o}}\right) - :doc:`(doc) ` Surface resistance of metal .. math:: R = \sqrt{\frac{\omega \mu}{2 G}} - :doc:`(doc) ` Wave resistance of coaxial waveguide .. math:: R = \frac{\sqrt{\frac{\mu_0 \mu_\text{r}}{\varepsilon_0 \varepsilon_\text{r}}}}{2 \pi} \log \left( \frac{r_\text{o}}{r_\text{i}} \right) - :doc:`(doc) ` Wavelength in rectangular waveguide .. math:: \lambda_\text{g} = \frac{\lambda}{\sqrt{1 - \left(\frac{\lambda}{\lambda_\text{c}}\right)^{2}}} - :doc:`(doc) ` :code:`laws.electricity.maxwell_equations` .. toggle:: - :doc:`(doc) ` Divergence of electric displacement field is volumetric charge density .. math:: \text{div} \, {\vec D} \left( {\vec r} \right) = \rho{\left({\vec r} \right)} - :doc:`(doc) ` Curl of magnetic field is free current density and electric displacement derivative .. math:: \text{curl} \, {\vec H} \left( {\vec r}, t \right) = {\vec J}_\text{f} \left( {\vec r}, t \right) + \frac{\partial}{\partial t} {\vec D} \left( {\vec r}, t \right) - :doc:`(doc) ` Curl of electric field is negative magnetic flux density derivative .. math:: \text{curl} \, {\vec E} \left( {\vec r}, t \right) = - \frac{\partial}{\partial t} {\vec B} \left( {\vec r}, t \right) - :doc:`(doc) ` :code:`laws.electricity.vector` .. toggle:: - :doc:`(doc) ` Current density is charge density times drift velocity .. math:: {\vec j} = \rho {\vec u} - :doc:`(doc) ` Electric dipole moment is charge times displacement .. math:: {\vec p} = q {\vec d} - :doc:`(doc) ` Electric dipole moment of electrically neutral system .. math:: {\vec p} = \sum_i {q}_{i} {{\vec r}}_{i} - :doc:`(doc) ` Electric field is force over test charge (Vector) .. math:: {\vec E} = \frac{{\vec F}}{q_{0}} - :doc:`(doc) ` Electric flux of uniform electric field .. math:: \Phi_{\vec E} = \left( {\vec E}, {\vec A} \right) - :doc:`(doc) ` Force acting on dipole in non-uniform electric field .. math:: {\vec F} = p \frac{d}{d x} {\vec E} \left( x \right) - :doc:`(doc) ` Lorentz force via electromagnetic field .. math:: {\vec F} = q \left({\vec E} + \left[ {\vec v}, {\vec B} \right]\right) - :doc:`(doc) ` Magnetic field due to constant filamentary current .. math:: d \vec{B} = \frac{\mu}{4 \pi} \frac{I \left[ d \vec{\ell}, {\vec r} - \vec{\ell} \right]}{\left \Vert {\vec r} - \vec{\ell} \right \Vert^{3}} - :doc:`(doc) ` Potential energy of electric dipole in uniform electric field .. math:: U = - \left( {\vec p}, {\vec E} \right) - :doc:`(doc) ` Torque due to electric dipole moment in uniform electric field .. math:: {\vec \tau} = \left[ {\vec p}, {\vec E} \right] - :doc:`(doc) ` :code:`laws.geometry` .. toggle:: - :doc:`(doc) ` Cross product is proportional to sine of angle between vectors .. math:: \left \Vert \left[ \vec u, \vec v \right] \right \Vert = u v \sin{\left(\varphi \right)} - :doc:`(doc) ` Dot product is proportional to cosine of angle between vectors .. math:: \left( \vec u, \vec v \right) = u v \cos{\left(\varphi \right)} - :doc:`(doc) ` Scalar projection is vector length times cosine of angle .. math:: s = a \cos{\left(\varphi \right)} - :doc:`(doc) ` :code:`laws.geometry.vector` .. toggle:: - :doc:`(doc) ` Dot product is proportional to cosine of angle between vectors (vector) .. math:: \left( {\vec u}, {\vec v} \right) = \left \Vert {\vec u} \right \Vert \left \Vert {\vec v} \right \Vert \cos{\left(\varphi \right)} - :doc:`(doc) ` :code:`laws.gravity` .. toggle:: - :doc:`(doc) ` Angle of rotation during gravitational maneuver .. math:: \varphi = 2 \operatorname{atan}{\left(\frac{G m}{d v^{2}} \right)} - :doc:`(doc) ` Area rate of change is proportional to angular momentum .. math:: \frac{d}{d t} A{\left(t \right)} = \frac{L}{2 m} - :doc:`(doc) ` Corrected planet period squared is proportional to cube of semimajor axis .. math:: T^{2} = \frac{4 \pi^{2} a^{3}}{G \left(M + m\right)} - :doc:`(doc) ` Easterly deviation from plumbline of falling bodies .. math:: s_\text{east} = \frac{4 \pi}{3} \frac{t}{T} h \cos{\left(\phi \right)} - :doc:`(doc) ` Eccentricity of orbit .. math:: e = \sqrt{1 - \left(\frac{b}{a}\right)^{2}} - :doc:`(doc) ` First escape speed .. math:: v = \sqrt{\frac{G m}{r + h}} - :doc:`(doc) ` Free fall acceleration from height .. math:: a = \frac{G m}{\left(r + h\right)^{2}} - :doc:`(doc) ` Gravitational potential energy .. math:: U = - \frac{G m_{1} m_{2}}{d} - :doc:`(doc) ` Gravitational radius of massive body .. math:: r = \frac{2 G m}{c^{2}} - :doc:`(doc) ` Gravitational force from mass and distance .. math:: F = \frac{G m_{1} m_{2}}{d^{2}} - :doc:`(doc) ` Kepler's constant via attracting body mass .. math:: \mathfrak{K} = \frac{G M}{4 \pi^{2}} - :doc:`(doc) ` Semimajor axis of orbit via mass and speed .. math:: a = \frac{G m}{v^{2}} - :doc:`(doc) ` Maximum angle of rotation during gravitational maneuver .. math:: \varphi = \operatorname{atan}{\left(\left(\frac{v_{1}}{v}\right)^{2} \right)} - :doc:`(doc) ` Maximum height of body thrown at angle to horizon .. math:: h = \frac{v_{0}^{2} \sin^{2}{\left(\varphi \right)}}{2 g} - :doc:`(doc) ` Time of flight of a projectile via initial velocity .. math:: t = \frac{2 v_{0} \sin{\left(\varphi \right)}}{g} - :doc:`(doc) ` Time of flight of a projectile via maximum height .. math:: t = \sqrt{\frac{2 h}{g}} - :doc:`(doc) ` Orbital speed from semimajor axis and planet mass .. math:: v = \sqrt{G m \left(\frac{2}{d} - \frac{1}{a}\right)} - :doc:`(doc) ` Planet period squared is proportional to cube of semimajor axis .. math:: T^{2} = \frac{4 \pi^{2}}{G m} a^{3} - :doc:`(doc) ` Radius of geostationary orbit .. math:: r = \sqrt[3]{\frac{G m}{\omega^{2}}} - :doc:`(doc) ` Horizontal displacement of projectile .. math:: d = \frac{v_{0}^{2} \sin{\left(2 \varphi \right)}}{g} - :doc:`(doc) ` Second escape velocity .. math:: v = \sqrt{\frac{2 G m}{r + h}} - :doc:`(doc) ` Southerly deviation from plumbline of falling bodies .. math:: s_\text{south} = \pi \frac{t}{T} s_\text{east} \sin{\left(\phi \right)} - :doc:`(doc) ` Third cosmic speed from orbital and second cosmic speed .. math:: v_{3} = \sqrt{\left(\sqrt{2} - 1\right)^{2} v^{2} + v_{2}^{2}} - :doc:`(doc) ` :code:`laws.gravity.radial_motion` .. toggle:: - :doc:`(doc) ` Average potential energy via average kinetic energy .. math:: \langle U \rangle = - 2 \langle K \rangle - :doc:`(doc) ` Potential energy of radial planetary motion .. math:: U_\text{tot} = U_\text{gr} + \frac{L^{2}}{2 m d^{2}} - :doc:`(doc) ` Radial kinetic energy plus potential energy is constant .. math:: \frac{m v_{r}^{2}}{2} + U = E - :doc:`(doc) ` Semimajor axis via Kepler's constant and total energy .. math:: a = \frac{2 \pi^{2} \mathfrak{K}}{\left|{\varepsilon}\right|} - :doc:`(doc) ` Semiminor axis of elliptical orbit via orbit parameters .. math:: b = 2 \sigma \sqrt{\frac{a}{G M}} - :doc:`(doc) ` Total energy is negative average kinetic energy .. math:: E = - \langle K \rangle - :doc:`(doc) ` :code:`laws.gravity.vector` .. toggle:: - :doc:`(doc) ` Acceleration due to gravity via gravity force and centripetal acceleration .. math:: {\vec g} = \frac{{\vec F}}{m} - {\vec a}_\text{cp} - :doc:`(doc) ` Falling body displacement .. math:: {\vec s} = {\vec v}_{0} t + t^{2} \left(\frac{{\vec g}}{2} + \left[ {\vec v}_{0}, {\vec \omega} \right]\right) + \frac{t^{3}}{3} \left(\left[ {\vec g}, {\vec \omega} \right] + 2 \left[ \left[ {\vec v}_{0}, {\vec \omega} \right], {\vec \omega} \right]\right) + \frac{t^{4}}{6} \left[ \left[ {\vec g}, {\vec \omega} \right], {\vec \omega} \right] - :doc:`(doc) ` Relative acceleration from force and acceleration due to gravity .. math:: {\vec a}_\text{rel} = {\vec g} - {\vec a}_\text{Cor} + \frac{{\vec F}}{m} - :doc:`(doc) ` :code:`laws.hydro` .. toggle:: - :doc:`(doc) ` Bulk stress is bulk modulus times strain .. math:: \Delta p = K e_{V} - :doc:`(doc) ` Capillary height via surface tension and contact angle .. math:: h = \frac{2 \gamma \cos{\left(\varphi \right)}}{\rho r g} - :doc:`(doc) ` Dynamic pressure from density and flow speed .. math:: q = \frac{\rho u^{2}}{2} - :doc:`(doc) ` Efficiency of hydraulic press from force and height .. math:: \eta = \frac{F_{2} d_{2}}{F_{1} d_{1}} - :doc:`(doc) ` Efflux speed via height .. math:: u = \sqrt{2 g h} - :doc:`(doc) ` Efflux speed via hydrostatic pressure and density .. math:: u = \sqrt{\frac{2 p}{\rho}} - :doc:`(doc) ` Excess pressure under curved surface of bubble .. math:: \Delta p = \frac{4 \gamma}{r} - :doc:`(doc) ` Force to area ratio in hydraulic press .. math:: \frac{F_{1}}{A_{1}} = \frac{F_{2}}{A_{2}} - :doc:`(doc) ` Froude number via flow speed and characteristic length .. math:: \text{Fr} = \frac{u}{\sqrt{g l_\text{c}}} - :doc:`(doc) ` Hydrostatic pressure via density and height .. math:: p = \rho g h - :doc:`(doc) ` Hydrostatic pressure via density, height and acceleration .. math:: p = \rho a h - :doc:`(doc) ` Inner pressure is constant .. math:: \frac{d}{d t} p_\text{inner}{\left(t \right)} = 0 - :doc:`(doc) ` Inner pressure is sum of pressures .. math:: p_\text{inner} = p_\text{static} + q + p - :doc:`(doc) ` Laplace pressure is pressure difference .. math:: p_\text{L} = p_\text{o} - p_\text{i} - :doc:`(doc) ` Mach number is flow speed over speed of sound .. math:: \text{M} = \frac{u}{c} - :doc:`(doc) ` Nusselt number via thermal parameters and characteristic length .. math:: \text{Nu} = \frac{h l_\text{c}}{k} - :doc:`(doc) ` Pressure difference at pipe ends from dynamic viscosity and flow rate .. math:: \Delta p = \frac{8 \mu l Q}{\pi r^{4}} - :doc:`(doc) ` Pressure of liquid in vessel moving horizontally .. math:: p = \rho \sqrt{g^{2} + a^{2}} h - :doc:`(doc) ` Pressure of liquid in vessel moving vertically .. math:: p = \rho \sqrt{\left(g + a\right)^{2}} h - :doc:`(doc) ` Reynolds number via fluid parameters and characteristic length .. math:: \text{Re} = \frac{\rho u l_\text{c}}{\mu} - :doc:`(doc) ` Shear stress is proportional to speed gradient .. math:: \tau = \mu \frac{d}{d x} u{\left(x \right)} - :doc:`(doc) ` Submerged volume of floating body via density ratio .. math:: \frac{V_\text{fl}}{V} = \frac{\rho}{\rho_\text{fl}} - :doc:`(doc) ` Surface tension force via surface tension and length .. math:: F = \gamma l - :doc:`(doc) ` Volume flux is constant .. math:: \frac{d}{d t} A{\left(t \right)} u{\left(t \right)} = 0 - :doc:`(doc) ` Apparent weight of a fully submersed body in fluid .. math:: W_\text{fl} = W_\text{vac} \left(1 - \frac{\rho_\text{fl}}{\rho_\text{b}}\right) - :doc:`(doc) ` :code:`laws.kinematics` .. toggle:: - :doc:`(doc) ` Angular momentum is rotational inertia times angular speed .. math:: L = I \omega - :doc:`(doc) ` Angular position is arc length over radius .. math:: \theta = \frac{s}{r} - :doc:`(doc) ` Angular position via constant angular acceleration and time .. math:: \theta = \theta_{0} + \omega_{0} t + \frac{\alpha t^{2}}{2} - :doc:`(doc) ` Angular position via constant angular speed and time .. math:: \theta = \theta_{0} + \omega t - :doc:`(doc) ` Angular speed via constant angular acceleration and time .. math:: \omega = \omega_{0} + \alpha t - :doc:`(doc) ` Average angular speed is angular distance over time .. math:: \langle \omega \rangle = \frac{\theta}{t} - :doc:`(doc) ` Centripetal acceleration via angular speed and radius .. math:: a_{n} = \omega^{2} r - :doc:`(doc) ` Centripetal acceleration via linear speed and radius .. math:: a_{n} = \frac{v^{2}}{r} - :doc:`(doc) ` Classical addition of velocities .. math:: v_{OA} = v_{OB} + v_{BA} - :doc:`(doc) ` Displacement in simple harmonic motion .. math:: q = q_\text{max} \cos{\left(\omega t + \varphi \right)} - :doc:`(doc) ` Position via constant acceleration and time .. math:: x = x_{0} + v_{0} t + \frac{a t^{2}}{2} - :doc:`(doc) ` Position via constant speed and time .. math:: x = x_{0} + v t - :doc:`(doc) ` Speed via angular speed and radius .. math:: v = \omega r - :doc:`(doc) ` Speed via constant acceleration and time .. math:: v = v_{0} + a t - :doc:`(doc) ` Tangential acceleration via angular acceleration and radius .. math:: a_{\tau} = \alpha r - :doc:`(doc) ` :code:`laws.kinematics.damped_oscillations` .. toggle:: - :doc:`(doc) ` Damped angular frequency .. math:: \omega_\text{d} = \omega \sqrt{1 - \zeta^{2}} - :doc:`(doc) ` Damping ratio from decay constant and undamped frequency .. math:: \zeta = \frac{\lambda}{\omega} - :doc:`(doc) ` Displacement in critical damping .. math:: d = \exp{\left(- \omega t \right)} \left(x_{0} + \left(v_{0} + x_{0} \omega\right) t\right) - :doc:`(doc) ` Displacement in underdamping .. math:: d = a \exp{\left(- \lambda t \right)} \cos{\left(\omega_\text{d} t + \varphi \right)} - :doc:`(doc) ` :code:`laws.kinematics.rotational_inertia` .. toggle:: - :doc:`(doc) ` Rotational inertia about axis and through center of mass .. math:: I = I_\text{com} + m d^{2} - :doc:`(doc) ` Rotational inertia in terms of Cartesian integral .. math:: I = \int\limits_{z_{0}}^{z_{1}}\int\limits_{y_{0}}^{y_{1}}\int\limits_{x_{0}}^{x_{1}} \rho{\left(x,y,z \right)} r^{2}{\left(x,y,z \right)}\, dx\, dy\, dz - :doc:`(doc) ` Rotational inertia in terms of a cylindrical integral .. math:: I = \int\limits_{h_{0}}^{h_{1}}\int\limits_{\varphi_{0}}^{\varphi_{1}}\int\limits_{r_{0}}^{r_{1}} \rho{\left(r,\varphi,h \right)} r^{3}\, dr\, d\varphi\, dh - :doc:`(doc) ` Rotational inertia is additive .. math:: I = \sum_k {I}_{k} - :doc:`(doc) ` Rotational inertia of a particle .. math:: I = m r^{2} - :doc:`(doc) ` :code:`laws.kinematics.rotational_inertia.geometries` .. toggle:: - :doc:`(doc) ` Slab about perpendicular axis through center .. math:: I = \frac{m \left(l_{1}^{2} + l_{2}^{2}\right)}{12} - :doc:`(doc) ` Solid disk about central axis .. math:: I = \frac{m r^{2}}{2} - :doc:`(doc) ` Thin rod about axis through center perpendicular to length .. math:: I = \frac{m l^{2}}{12} - :doc:`(doc) ` :code:`laws.kinematics.vector` .. toggle:: - :doc:`(doc) ` Absolute velocity of arbitrary motion .. math:: {\vec v}_\text{abs} = {\vec v}_\text{rel} + {\vec v}_\text{tr} - :doc:`(doc) ` Acceleration due to non-uniform rotation .. math:: {\vec a}_\text{rot} = \left[ \frac{d}{d t} {\vec \omega} \left( t \right), {\vec r} \right] - :doc:`(doc) ` Acceleration is normal plus tangential acceleration .. math:: {\vec a} = {\vec a}_\text{n} + {\vec a}_\text{t} - :doc:`(doc) ` Acceleration of transfer between relative frames .. math:: {\vec a}_\text{tr} = {\vec a}_{0} + {\vec a}_\text{cp} + {\vec a}_\text{rot} - :doc:`(doc) ` Centrifugal acceleration via centripetal acceleration .. math:: {\vec a}_\text{cf} = - {\vec a}_\text{cp} - :doc:`(doc) ` Centripetal acceleration via cross product .. math:: {\vec a}_\text{cp} = \left[ {\vec \omega}, \left[ {\vec \omega}, {\vec r} \right] \right] - :doc:`(doc) ` Centripetal acceleration via vector rejection .. math:: {\vec a}_\text{cp} = {\vec \omega} \left( {\vec r}, {\vec \omega} \right) - {\vec r} \left( {\vec \omega}, {\vec \omega} \right) - :doc:`(doc) ` Coriolis acceleration .. math:: {\vec a}_\text{Cor} = 2 \left[ {\vec v}_\text{rel}, {\vec \omega} \right] - :doc:`(doc) ` Linear displacement is angular displacement cross radius .. math:: {\vec s} = \left[ {\vec \theta}, {\vec r} \right] - :doc:`(doc) ` Velocity of transfer between reference frames .. math:: {\vec v}_\text{tr} = {\vec v}_{0} + \left[ {\vec \omega}, {\vec r} \right] - :doc:`(doc) ` Velocity relative to reference frame .. math:: {\vec v} \left( t \right) = \frac{d}{d t} {\vec r} \left( t \right) - :doc:`(doc) ` :code:`laws.nuclear` .. toggle:: - :doc:`(doc) ` Diffusion area from diffusion coefficient and absorption cross section .. math:: L^{2} = \frac{D}{\Sigma_\text{a}} - :doc:`(doc) ` Diffusion equation from neutron flux .. math:: - D \nabla^{2} \Phi{\left(x \right)} + \Sigma_\text{a} \Phi{\left(x \right)} = \frac{\nu}{k_\text{eff}} \Sigma_\text{f} \Phi{\left(x \right)} - :doc:`(doc) ` Effective multiplication factor from infinite multiplication factor and probabilities .. math:: k_\text{eff} = k_{\infty} P_\text{FNL} P_\text{TNL} - :doc:`(doc) ` Fast fission factor from resonance escape probability .. math:: \varepsilon = 1 + \frac{1 - p}{p} \frac{\nu_\text{f} P_\text{FAF} u_\text{f}}{\nu_\text{t} P_\text{TNL} P_\text{TAF} f} - :doc:`(doc) ` Fast non-leakage probability from Fermi age and geometric buckling .. math:: P_\text{FNL} = \exp{\left(- B_\text{g}^2 \tau \right)} - :doc:`(doc) ` Infinite multiplication factor formula .. math:: k_{\infty} = \eta \varepsilon p f - :doc:`(doc) ` Infinite multiplication factor from macroscopic cross sections .. math:: k_{\infty} = \frac{\nu \Sigma_\text{f}}{\Sigma_\text{a}} - :doc:`(doc) ` Solution to the exponential decay equation .. math:: X = X_{0} \cdot 2^{- \frac{t}{t_{1/2}}} - :doc:`(doc) ` Macroscopic cross section from mean free path .. math:: \Sigma = \frac{1}{\lambda} - :doc:`(doc) ` Macroscopic cross section from microscopic cross section and number density .. math:: \Sigma = \sigma n - :doc:`(doc) ` Macroscopic transport cross section from macroscopic scattering cross section .. math:: \Sigma_\text{tr} = \sigma_\text{s} \left(1 - \mu\right) - :doc:`(doc) ` Migration area from diffusion length and Fermi age .. math:: M^{2} = L^{2} + \tau - :doc:`(doc) ` Average cosine of scattering angle from mass number .. math:: \mu = \frac{2}{3 A} - :doc:`(doc) ` Diffusion coefficient from macroscopic scattering cross section .. math:: D = \frac{1}{3 \Sigma_\text{tr}} - :doc:`(doc) ` Reproduction factor from macroscopic cross sections in fuel .. math:: \eta = \frac{\nu \Sigma_\text{f}^\text{f}}{\Sigma_\text{a}^\text{f}} - :doc:`(doc) ` Resonance escape probability from resonance absorption integral .. math:: p = \exp{\left(- \frac{n J_\text{eff}}{\xi \Sigma_\text{s}} \right)} - :doc:`(doc) ` Thermal non-leakage probability from diffusion area and geometric buckling .. math:: P_\text{TNL} = \frac{1}{1 + L_\text{th}^2 B_\text{g}^2} - :doc:`(doc) ` Thermal utilization factor from macroscopic absorption cross sections .. math:: f = \frac{\Sigma_\text{a}^\text{f}}{\Sigma_\text{a}} - :doc:`(doc) ` :code:`laws.nuclear.buckling` .. toggle:: - :doc:`(doc) ` Geometric buckling for uniform cylinder .. math:: B_\text{g}^2 = \left(\frac{2.405}{r}\right)^{2} + \left(\frac{\pi}{h}\right)^{2} - :doc:`(doc) ` Geometric buckling for uniform parallelepiped .. math:: B_\text{g}^2 = \left(\frac{\pi}{l_{1}}\right)^{2} + \left(\frac{\pi}{l_{2}}\right)^{2} + \left(\frac{\pi}{l_{3}}\right)^{2} - :doc:`(doc) ` Geometric buckling for uniform slab .. math:: B_\text{g}^2 = \left(\frac{\pi}{h}\right)^{2} - :doc:`(doc) ` Geometric buckling for uniform sphere .. math:: B_\text{g}^2 = \left(\frac{\pi}{r}\right)^{2} - :doc:`(doc) ` Geometric buckling from multiplication factors and diffusion area .. math:: B_\text{g}^2 = \frac{\frac{k_{\infty}}{k_\text{eff}} - 1}{L^{2}} - :doc:`(doc) ` Geometric buckling from macroscopic cross sections and diffusion coefficient .. math:: B_\text{g}^2 = \frac{\frac{\nu}{k_\text{eff}} \Sigma_\text{f} - \Sigma_\text{a}}{D} - :doc:`(doc) ` Geometric buckling from neutron flux .. math:: B_\text{g}^2 = - \frac{\nabla^{2} \Phi{\left(x \right)}}{\Phi{\left(x \right)}} - :doc:`(doc) ` Material buckling from material cross sections and diffusion coefficient .. math:: B_\text{m}^2 = \frac{\nu \Sigma_\text{f} - \Sigma_\text{a}}{D} - :doc:`(doc) ` Neutron flux for uniform cylinder .. math:: \Phi = \Phi_{0} J_{0}\left(\frac{2.405}{r_{0}} r\right) \cos{\left(\frac{\pi}{h_{0}} h \right)} - :doc:`(doc) ` Neutron flux for uniform parallelepiped .. math:: \Phi = \Phi_{0} \cos{\left(\frac{\pi}{l_{2}} x_{1} \right)} \cos{\left(\frac{\pi}{l_{1}} x_{2} \right)} \cos{\left(\frac{\pi}{l_{3}} x_{3} \right)} - :doc:`(doc) ` Neutron flux for uniform slab .. math:: \Phi = \Phi_{0} \cos{\left(\frac{\pi}{h} z \right)} - :doc:`(doc) ` Neutron flux for uniform sphere .. math:: \Phi = \Phi_{0} \frac{\sin{\left(\frac{\pi}{r_{0}} r \right)}}{r} - :doc:`(doc) ` :code:`laws.optics` .. toggle:: - :doc:`(doc) ` Angle of light deflection in prism .. math:: b = a \left(n - 1\right) - :doc:`(doc) ` Angular magnification of telescope .. math:: M_\text{A} = \frac{F}{f} - :doc:`(doc) ` Bragg diffraction from angle of diffraction and wavelength .. math:: d = \frac{N \lambda}{2 \sin{\left(\varphi \right)}} - :doc:`(doc) ` Film thickness for minimum interference .. math:: h = \frac{k \lambda}{2 n \cos{\left(\varphi \right)}} - :doc:`(doc) ` Focal length of a concave spherical mirror .. math:: f = \frac{r}{2} - :doc:`(doc) ` Interference due to two slits .. math:: \Lambda = \frac{x d}{l} - :doc:`(doc) ` Interference maximum .. math:: \Lambda = N \lambda - :doc:`(doc) ` Interference minimum .. math:: \Lambda = \frac{\left(2 N + 1\right) \lambda}{2} - :doc:`(doc) ` Irradiance of light after polarizer .. math:: E_\text{e} = E_{\text{e}0} k \cos^{2}{\left(\varphi \right)} - :doc:`(doc) ` Lens focus from object and image .. math:: \frac{1}{f} = \frac{1}{d_\text{o}} + \frac{1}{d_\text{i}} - :doc:`(doc) ` Light pressure .. math:: p = \frac{I \left(1 + R\right)}{c} - :doc:`(doc) ` Linear magnification from distance to object and distance to image .. math:: M = \frac{d_\text{i}}{d_\text{o}} - :doc:`(doc) ` Linear magnification from object height and image height .. math:: M = \frac{h_\text{i}}{h_\text{o}} - :doc:`(doc) ` Optical distance difference from optical distances .. math:: \Delta \Lambda = \Lambda_{2} - \Lambda_{1} - :doc:`(doc) ` Optical path length from geometrical path length and refractive index .. math:: \Lambda = n s - :doc:`(doc) ` Optical power from focus distance .. math:: D = \frac{1}{f} - :doc:`(doc) ` Optical power from thin lens radii and refractive indices .. math:: D = \left(n - n_{0}\right) \left(\frac{1}{r_{1}} - \frac{1}{r_{2}}\right) - :doc:`(doc) ` Optical power of spherical lens from refractive indices and distances .. math:: - \frac{n_{0}}{d_\text{o}} + \frac{n}{d_\text{i}} = \frac{n - n_{0}}{r} - :doc:`(doc) ` Radiation intensity from energy, area, and time .. math:: I = \frac{E}{A t} - :doc:`(doc) ` Radius of dark Newton's ring formula .. math:: r = \sqrt{\frac{N R \lambda}{n}} - :doc:`(doc) ` Refraction angle from enviroments .. math:: n_{1} \sin{\left(\varphi_{1} \right)} = n_{2} \sin{\left(\varphi_{2} \right)} - :doc:`(doc) ` Relative aperture of telescope .. math:: A = \frac{D}{f} - :doc:`(doc) ` Resolution of telescope .. math:: \theta = A \frac{\lambda}{D} - :doc:`(doc) ` :code:`laws.quantities` .. toggle:: - :doc:`(doc) ` Fractional change is change over initial value .. math:: e_{X} = \frac{\Delta X}{X} - :doc:`(doc) ` Quantity is areal density times volume .. math:: X = \sigma_{X} A - :doc:`(doc) ` Extensive quantity is linear density times length .. math:: X = \lambda_{X} l - :doc:`(doc) ` Quantity is molar quantity times amount of substance .. math:: X = x_{m} n - :doc:`(doc) ` Quantity is specific quantity times mass .. math:: X = x m - :doc:`(doc) ` Quantity is volumetric density times volume .. math:: X = \rho_{X} V - :doc:`(doc) ` :code:`laws.quantum_mechanics` .. toggle:: - :doc:`(doc) ` Probability density of quantum state .. math:: \rho = \left|{\psi}\right|^{2} - :doc:`(doc) ` :code:`laws.quantum_mechanics.harmonic_oscillator` .. toggle:: - :doc:`(doc) ` Energy levels of harmonic oscillator .. math:: E_{n} = \left(N + \frac{1}{2}\right) \hbar \omega - :doc:`(doc) ` Quantum harmonic oscillator equation .. math:: - \frac{\hbar^{2}}{2 m} \frac{d^{2}}{d x^{2}} \psi{\left(x \right)} + \frac{m \omega^{2}}{2} x^{2} \psi{\left(x \right)} = E \psi{\left(x \right)} - :doc:`(doc) ` Wave eigenfunctions of quantum harmonic oscillator .. math:: \psi = \frac{\sqrt[4]{\frac{m \omega}{\pi \hbar}}}{\sqrt{2^{N} N!}} \exp{\left(- \frac{m \omega}{2 \hbar} x^{2} \right)} H_{N}\left(\sqrt{\frac{m \omega}{\hbar}} x\right) - :doc:`(doc) ` :code:`laws.quantum_mechanics.schrodinger` .. toggle:: - :doc:`(doc) ` Free particle plane wave solution .. math:: \psi = \exp{\left(\frac{i}{\hbar} \left(p x - E t\right) \right)} - :doc:`(doc) ` Time dependent Schrödinger equation in one dimension .. math:: - \frac{\hbar^{2}}{2 m} \frac{\partial^{2}}{\partial x^{2}} \psi{\left(x,t \right)} + U{\left(x \right)} \psi{\left(x,t \right)} = i \hbar \frac{\partial}{\partial t} \psi{\left(x,t \right)} - :doc:`(doc) ` Time dependent solution via time independent solution .. math:: \Psi{\left(x,t \right)} = \psi{\left(x \right)} \exp{\left(- \frac{i}{\hbar} E t \right)} - :doc:`(doc) ` Time independent solution in one dimension .. math:: - \frac{\hbar^{2}}{2 m} \frac{d^{2}}{d x^{2}} \psi{\left(x \right)} + U{\left(x \right)} \psi{\left(x \right)} = E \psi{\left(x \right)} - :doc:`(doc) ` :code:`laws.relativistic` .. toggle:: - :doc:`(doc) ` Coordinate conversion at constant velocity .. math:: x_{2} = \frac{x_{1} - v t_{1}}{\sqrt{1 - \left(\frac{v}{c}\right)^{2}}} - :doc:`(doc) ` Lorentz transformation of time .. math:: t' = \frac{t - \frac{v x}{c^{2}}}{\sqrt{1 - \left(\frac{v}{c}\right)^{2}}} - :doc:`(doc) ` Proper time for timelike intervals .. math:: \Delta \tau = \frac{\Delta s}{c} - :doc:`(doc) ` Relativistic kinetic energy .. math:: K = \left(\gamma - 1\right) m_{0} c^{2} - :doc:`(doc) ` Relativistic length via rest length and speed .. math:: l = l_{0} \sqrt{1 - \frac{v^{2}}{c^{2}}} - :doc:`(doc) ` Relativistic mass via rest mass and speed .. math:: m = \frac{m_{0}}{\sqrt{1 - \frac{v^{2}}{c^{2}}}} - :doc:`(doc) ` Relativistic momentum via rest mass and speed .. math:: p = \frac{m_{0} v}{\sqrt{1 - \left(\frac{v}{c}\right)^{2}}} - :doc:`(doc) ` Relativistic sum of velocities .. math:: v_{OL} = \frac{v_{OP} + v_{PL}}{1 + \frac{v_{OP} v_{PL}}{c^{2}}} - :doc:`(doc) ` Relativistic time dilation .. math:: t = \frac{\tau}{\sqrt{1 - \frac{v^{2}}{c^{2}}}} - :doc:`(doc) ` Spacetime interval via time and distance .. math:: s^{2} = \left(c t\right)^{2} - d^{2} - :doc:`(doc) ` Spacetime interval is Lorentz invariant .. math:: s_{2} = s_{1} - :doc:`(doc) ` Total energy via momentum and rest mass .. math:: E^{2} = \left(p c\right)^{2} + \left(m_{0} c^{2}\right)^{2} - :doc:`(doc) ` Total energy via relativistic mass .. math:: E = m c^{2} - :doc:`(doc) ` :code:`laws.relativistic.vector` .. toggle:: - :doc:`(doc) ` Acceleration from force and velocity .. math:: {\vec a} = \frac{{\vec F} - \frac{\left( {\vec F}, {\vec v} \right)}{c^{2}} {\vec v}}{m_{0} \gamma} - :doc:`(doc) ` Force from acceleration and velocity .. math:: {\vec F} = \gamma^{3} m_{0} {\vec a}_\text{t} + \gamma m_{0} {\vec a}_\text{n} - :doc:`(doc) ` Relativistic mass moment .. math:: {\vec N} = m_{0} \gamma^{2} \left({\vec r} - {\vec v} t\right) - :doc:`(doc) ` Relativistic velocity normal to movement .. math:: {\vec u}_\text{n} = \frac{\left({\vec u'} - \frac{\left( {\vec u'}, {\vec v} \right)}{\left( {\vec v}, {\vec v} \right)} {\vec v}\right) \sqrt{1 - \frac{\left( {\vec v}, {\vec v} \right)}{c^{2}}}}{1 + \frac{\left( {\vec u'}, {\vec v} \right)}{c^{2}}} - :doc:`(doc) ` Relativistic velocity tangential to movement .. math:: {\vec u}_\text{t} = \frac{{\vec v} \left(\frac{\left( {\vec u'}, {\vec v} \right)}{\left( {\vec v}, {\vec v} \right)} + 1\right)}{1 + \frac{\left( {\vec u'}, {\vec v} \right)}{c^{2}}} - :doc:`(doc) ` :code:`laws.thermodynamics` .. toggle:: - :doc:`(doc) ` Average kinetic energy of ideal gas from temperature .. math:: \langle K \rangle = \frac{3 k_\text{B}}{2} T - :doc:`(doc) ` Average speed in Maxwell—Boltzmann statistics .. math:: \langle v \rangle = \sqrt{\frac{8 k_\text{B} T}{\pi m}} - :doc:`(doc) ` Average square speed in Maxwell—Boltzmann statistics .. math:: \langle v^{2} \rangle = \frac{3 k_\text{B} T}{m} - :doc:`(doc) ` Canonical partition function of a classical discrete system .. math:: Z = \sum_i {f}_{i} - :doc:`(doc) ` Change in entropy of ideal gas from volume and temperature .. math:: S = \frac{m}{M} \left(c_{V, \text{m}} \log \left( \frac{T_{1}}{T_{0}} \right) + R \log \left( \frac{V_{1}}{V_{0}} \right)\right) - :doc:`(doc) ` Chemical potential is Gibbs energy per particle .. math:: \mu = \frac{G}{N} - :doc:`(doc) ` Chemical potential is particle count derivative of enthalpy .. math:: \mu = \frac{\partial}{\partial N} H{\left(S,p,N \right)} - :doc:`(doc) ` Chemical potential is particle count derivative of free energy .. math:: \mu = \frac{\partial}{\partial N} F{\left(T,V,N \right)} - :doc:`(doc) ` Chemical potential is particle count derivative of Gibbs energy .. math:: \mu = \frac{\partial}{\partial N} G{\left(T,p,N \right)} - :doc:`(doc) ` Chemical potential is particle count derivative of internal energy .. math:: \mu = \frac{\partial}{\partial N} U{\left(S,V,N \right)} - :doc:`(doc) ` Chemical potential of ideal gas .. math:: \mu = k_\text{B} T \log \left( n \lambda^{3} \right) - :doc:`(doc) ` Classical isochoric molar heat capacity of solids .. math:: c_{p, \text{m}} = 3 R - :doc:`(doc) ` Compressibility factor via intermolecular force potential .. math:: Z = 1 + \frac{2 \pi N}{V} \int\limits_{0}^{\infty} \left(1 - \exp{\left(- \frac{U{\left(r \right)}}{k_\text{B} T} \right)}\right) r^{2}\, dr - :doc:`(doc) ` Diffusion coefficient of spherical Brownian particles from temperature and dynamic viscosity .. math:: D = \frac{R T}{6 N_\text{A} \pi r \mu} - :doc:`(doc) ` Diffusion flux from diffusion coefficient and concentration gradient .. math:: J{\left(x \right)} = - D \frac{d}{d x} c{\left(x \right)} - :doc:`(doc) ` Dynamic viscosity from temperature .. math:: \mu = \mu_{0} \frac{T_{0} + S}{T + S} \left(\frac{T}{T_{0}}\right)^{\frac{3}{2}} - :doc:`(doc) ` Efficiency of heat engine .. math:: \eta = 1 - \frac{Q_{r}}{Q_{h}} - :doc:`(doc) ` Enthalpy derivative via volume derivative .. math:: \frac{\partial}{\partial p} H{\left(T,p \right)} = V{\left(T,p \right)} - T \frac{\partial}{\partial T} V{\left(T,p \right)} - :doc:`(doc) ` Enthalpy differential .. math:: dH = T dS + V dp + \mu dN - :doc:`(doc) ` Enthalpy is internal energy plus pressure energy .. math:: H = U + p V - :doc:`(doc) ` Enthalpy via Gibbs energy .. math:: H = G{\left(T,p \right)} - T \frac{\partial}{\partial T} G{\left(T,p \right)} - :doc:`(doc) ` Entropy change in reversible process .. math:: d S = \frac{\delta Q}{T} - :doc:`(doc) ` Entropy derivative via volume derivative .. math:: \frac{\partial}{\partial p} S{\left(T,p \right)} = - \frac{\partial}{\partial T} V{\left(T,p \right)} - :doc:`(doc) ` Entropy from statistical weight .. math:: S = k_\text{B} \log \left( \Omega \right) - :doc:`(doc) ` Entropy is derivative of free energy .. math:: S = - \frac{\partial}{\partial T} F{\left(T,V,N \right)} - :doc:`(doc) ` Entropy is derivative of Gibbs energy .. math:: S = - \frac{\partial}{\partial T} G{\left(T,p,N \right)} - :doc:`(doc) ` Entropy of independent subsystems is sum of their entropies .. math:: S = \sum_i {S}_{i} - :doc:`(doc) ` Fractional volume change via small temperature change .. math:: e_{V} = \alpha_{V} \Delta T - :doc:`(doc) ` Free energy differential .. math:: dF = - S dT - p dV + \mu dN - :doc:`(doc) ` Gas mixture pressure from partial pressures .. math:: p = \sum_i {p}_{i} - :doc:`(doc) ` Gas pressure change from temperature .. math:: \Delta p = p_{0} \left(\frac{T}{T_\text{std}} - 1\right) - :doc:`(doc) ` Gibbs energy differential .. math:: dG = - S dT + V dp + \mu dN - :doc:`(doc) ` Gibbs energy via enthalpy .. math:: G = H - T S - :doc:`(doc) ` Grashof number .. math:: \text{Gr} = \frac{g \alpha_{V} \left(T_\text{s} - T_\text{b}\right) l_\text{c}^{3}}{\nu^{2}} - :doc:`(doc) ` Heat is heat capacity times temperature change .. math:: Q = C \Delta T - :doc:`(doc) ` Heat of combustion via mass .. math:: Q = \varepsilon_{q} m - :doc:`(doc) ` Heat of vaporization via mass .. math:: Q = \varepsilon_{L} m - :doc:`(doc) ` Helmholtz free energy via internal energy .. math:: F = U - T S - :doc:`(doc) ` Infinitesimal work in quasistatic process .. math:: \delta W = p d V - :doc:`(doc) ` Intensive parameters relation .. math:: S d T - V d p + N d \mu = 0 - :doc:`(doc) ` Internal energy change of ideal gas via temperature .. math:: dU = C_{V} dT - :doc:`(doc) ` Internal energy change via heat and work .. math:: d U = \delta Q - \delta W - :doc:`(doc) ` Internal energy differential .. math:: d U = T d S - p d V + \mu d N - :doc:`(doc) ` Internal energy of ideal gas via temperature .. math:: U = \frac{3 m R T}{2 M} - :doc:`(doc) ` Internal energy via Helmholtz free energy .. math:: U = F{\left(T,V \right)} - T \frac{\partial}{\partial T} F{\left(T,V \right)} - :doc:`(doc) ` Isentropic speed of sound via pressure derivative .. math:: v_\text{s} = \sqrt{\frac{\partial}{\partial \rho} p{\left(\rho,S \right)}} - :doc:`(doc) ` Isobaric molar heat capacity of ideal gas via adiabatic index .. math:: c_{p, \text{m}} = \frac{R \gamma}{\gamma - 1} - :doc:`(doc) ` Isobaric potential from heat capacity .. math:: \Delta G_\text{m} = \Delta H_\text{m} - T \Delta S_\text{m} - \Delta c_\text{m} T \left(\log \left( \frac{T}{T_\text{lab}} \right) + \frac{T_\text{lab}}{T} - 1\right) - :doc:`(doc) ` Isobaric potential of temperature dependent heat capacity .. math:: \Delta G_\text{m} = \Delta H_\text{m} - T S_\text{m} - T \left(a \left(\log \left( \frac{T_\text{lab}}{T} \right) + \frac{T_\text{lab}}{T} - 1\right) + b \left(\frac{T}{2} + \frac{T_\text{lab}^{2}}{2 T} - T_\text{lab}\right) + c \left(\frac{1}{T^{2} \cdot 2} - \frac{1}{T_\text{lab} T} + \frac{1}{T_\text{lab}^{2} \cdot 2}\right)\right) - :doc:`(doc) ` Isochoric and isobaric heat capacities of homogeneous substance .. math:: C_{p} - C_{V} = \frac{V T \alpha_{V}^{2}}{\beta_{T}} - :doc:`(doc) ` Isochoric and isobaric heat capacities of ideal gas .. math:: C_{p} - C_{V} = n R - :doc:`(doc) ` Isochoric molar heat capacity of ideal gas via adiabatic index .. math:: c_{V, \text{m}} = \frac{R}{\gamma - 1} - :doc:`(doc) ` Isochoric molar heat capacity of ideal gas via degrees of freedom .. math:: c_{V, \text{m}} = \frac{f}{2} R - :doc:`(doc) ` Laplace pressure of spherical shapes .. math:: P_\text{L} = \frac{2 \gamma}{r} - :doc:`(doc) ` Latent heat of fusion via mass .. math:: Q = \varepsilon_{\lambda} m - :doc:`(doc) ` Mean free path of random motion .. math:: \lambda = \frac{1}{\sqrt{2} \pi D^{2} n} - :doc:`(doc) ` Number of impacts on the wall from area and speed .. math:: N = \frac{n A v t}{2} - :doc:`(doc) ` Prandtl number via dynamic viscosity and thermal conductivity .. math:: \text{Pr} = \frac{c_{p} \mu}{k} - :doc:`(doc) ` Pressure and temperature in isochoric process .. math:: \frac{p_{0}}{p_{1}} = \frac{T_{0}}{T_{1}} - :doc:`(doc) ` Pressure and volume in isothermal process .. math:: p_{0} V_{0} = p_{1} V_{1} - :doc:`(doc) ` Pressure from number density and kinetic energy .. math:: p = \frac{2 n}{3} \langle K \rangle - :doc:`(doc) ` Pressure of ideal gas from height and temperature .. math:: p = p_{0} \exp{\left(- \frac{g m \Delta h}{k_\text{B} T} \right)} - :doc:`(doc) ` Probability of finding ideal gas molecules in volume .. math:: P = \left(\frac{V}{V_{0}}\right)^{N} - :doc:`(doc) ` Probability of ideal gas macrostate .. math:: P_\text{macro} = \Omega \prod_i {P}_{i}^{{N}_{i}} - :doc:`(doc) ` Quantum isochoric molar heat capacity of solids .. math:: c_{V, \text{m}} = 3 R \frac{x^{2} \exp{\left(x \right)}}{\left(\exp{\left(x \right)} - 1\right)^{2}} - :doc:`(doc) ` Radiance of black body from temperature .. math:: M_\text{e} = \sigma T^{4} - :doc:`(doc) ` Radiation power via temperature .. math:: P = \sigma \varepsilon A T^{4} - :doc:`(doc) ` Rate of energy conduction through slab .. math:: P = \frac{k A \left|{\Delta T}\right|}{h} - :doc:`(doc) ` Relative humidity is ratio of vapor pressure .. math:: \varphi = \frac{p}{p_\text{s}} - :doc:`(doc) ` Speed of sound in ideal gas .. math:: v_\text{s} = \sqrt{\frac{\gamma R T}{M}} - :doc:`(doc) ` Temperature derivative via volume derivative .. math:: \frac{\partial}{\partial p} T{\left(p,H \right)} = \frac{T{\left(p,H \right)} \frac{\partial}{\partial T{\left(p,H \right)}} V{\left(T{\left(p,H \right)},p \right)} - V{\left(T{\left(p,H \right)},p \right)}}{C_{p}} - :doc:`(doc) ` Temperature is derivative of internal energy .. math:: T = \frac{\partial}{\partial S} U{\left(S,V,N \right)} - :doc:`(doc) ` Total energy transfer is zero in adiabatically isolated system .. math:: \sum_i {E}_{i} = 0 - :doc:`(doc) ` Total particle count is sum of occupancies .. math:: N = \sum_i {N}_{i} - :doc:`(doc) ` Volume and temperature in isobaric process .. math:: \frac{V_{0}}{V_{1}} = \frac{T_{0}}{T_{1}} - :doc:`(doc) ` Volumetric and linear expansion coefficients in isotropic materials .. math:: \alpha_{V} = 3 \alpha_{l} - :doc:`(doc) ` Volumetric expansion coefficient of ideal gas .. math:: \alpha_{V} = \frac{1}{T} - :doc:`(doc) ` Work is integral of pressure over volume .. math:: W = \int\limits_{V_{0}}^{V_{1}} p{\left(V \right)}\, dV - :doc:`(doc) ` Work of ideal gas in isobaric process .. math:: W = p \left(V_{1} - V_{0}\right) - :doc:`(doc) ` Work of ideal gas in isothermal process .. math:: W = n R T \log \left( \frac{V_{1}}{V_{0}} \right) - :doc:`(doc) ` :code:`laws.thermodynamics.bose_einstein_statistics` .. toggle:: - :doc:`(doc) ` Single particle state distribution .. math:: n_{i} = \frac{1}{\exp{\left(\frac{E_{i} - \mu}{k_\text{B} T} \right)} - 1} - :doc:`(doc) ` :code:`laws.thermodynamics.dielectrics` .. toggle:: - :doc:`(doc) ` Enthalpy change via entropy change and electric field change .. math:: dH = T dS - D dE - :doc:`(doc) ` Enthalpy of dielectrics .. math:: H = U - E D - :doc:`(doc) ` Free energy change via temperature change and electric displacement change .. math:: dH = - S dT + E dD - :doc:`(doc) ` Gibbs energy change via temperature change and electric displacement change .. math:: dG = - S dT - D dE - :doc:`(doc) ` Gibbs energy of dielectrics .. math:: G = F - E D - :doc:`(doc) ` Internal energy change via heat and electric displacement change .. math:: dU = \delta Q + E dD - :doc:`(doc) ` :code:`laws.thermodynamics.equations_of_state` .. toggle:: - :doc:`(doc) ` Dieterici equation .. math:: p \left(V_{m} - b\right) = R T \exp{\left(- \frac{a}{R T V_{m}} \right)} - :doc:`(doc) ` Ideal gas equation .. math:: p V = n R T - :doc:`(doc) ` :code:`laws.thermodynamics.equations_of_state.van_der_waals` .. toggle:: - :doc:`(doc) ` Critical molar volume .. math:: v_{\text{c},\text{m}} = 3 b - :doc:`(doc) ` Critical pressure .. math:: p_\text{c} = \frac{a}{27 b^{2}} - :doc:`(doc) ` Critical temperature .. math:: T_\text{c} = \frac{8 a}{27 R b} - :doc:`(doc) ` Dimensionless equation .. math:: \left(p_{r} + \frac{3}{V_{r}^{2}}\right) \left(V_{r} - \frac{1}{3}\right) = \frac{8 T_{r}}{3} - :doc:`(doc) ` Molar internal energy .. math:: u_\text{m} = \int c_{V, \text{m}}{\left(T \right)}\, dT - \frac{a}{v_\text{m}} - :doc:`(doc) ` Reduced pressure .. math:: p_{r} = \frac{p}{p_\text{c}} - :doc:`(doc) ` Reduced temperature .. math:: T_{r} = \frac{T}{T_\text{c}} - :doc:`(doc) ` Reduced volume .. math:: V_{r} = \frac{V}{V_\text{c}} - :doc:`(doc) ` Second virial coefficient .. math:: C_{2} = b - \frac{a}{R T} - :doc:`(doc) ` Van der Waals equation .. math:: \left(p + \frac{a}{v_\text{m}^{2}}\right) \left(v_\text{m} - b\right) = R T - :doc:`(doc) ` :code:`laws.thermodynamics.euler_relations` .. toggle:: - :doc:`(doc) ` Enthalpy formula .. math:: H = T S + \mu N - :doc:`(doc) ` Gibbs energy formula .. math:: G = \mu N - :doc:`(doc) ` Internal energy formula .. math:: U = T S - p V + \mu N - :doc:`(doc) ` :code:`laws.thermodynamics.fermi_dirac_statistics` .. toggle:: - :doc:`(doc) ` Single-particle state distribution .. math:: N_{i} = \frac{1}{\exp{\left(\frac{E_{i} - \mu}{k_\text{B} T} \right)} + 1} - :doc:`(doc) ` :code:`laws.thermodynamics.heat_transfer` .. toggle:: - :doc:`(doc) ` Equation in homogeneous medium in one dimension .. math:: \frac{\partial}{\partial t} T{\left(x,t \right)} = \alpha \frac{\partial^{2}}{\partial x^{2}} T{\left(x,t \right)} - :doc:`(doc) ` General heat equation in 3D .. math:: \rho c_{p} \frac{\partial}{\partial t} T{\left({\vec r},t \right)} = \text{div} \, k{\left({\vec r} \right)} \text{grad} \, T{\left({\vec r},t \right)} + q{\left({\vec r} \right)} - :doc:`(doc) ` General equation in one dimension .. math:: \rho c_{p} \frac{\partial}{\partial t} T{\left(x,t \right)} = \frac{\partial}{\partial x} k{\left(x \right)} \frac{\partial}{\partial x} T{\left(x,t \right)} + q{\left(x,t \right)} - :doc:`(doc) ` Solution with zero temperature boundaries .. math:: T_{n} = B_{n} \sin{\left(\frac{N \pi x}{x_\text{max}} \right)} \exp{\left(- \alpha \left(\frac{N \pi}{x_\text{max}}\right)^{2} t \right)} - :doc:`(doc) ` :code:`laws.thermodynamics.maxwell_boltzmann_statistics` .. toggle:: - :doc:`(doc) ` Energy distribution .. math:: f(E) = \frac{2 \sqrt{\frac{E}{\pi}}}{T^{\frac{3}{2}} k_\text{B}^{\frac{3}{2}}} \exp{\left(- \frac{E}{k_\text{B} T} \right)} - :doc:`(doc) ` Most probable speed .. math:: v_\text{prob} = \sqrt{\frac{2 k_\text{B} T}{m}} - :doc:`(doc) ` Single-particle discrete distribution .. math:: N_{i} = \frac{N}{Z} \exp{\left(- \frac{E_{i}}{k_\text{B} T} \right)} - :doc:`(doc) ` Speed distribution .. math:: f(v) = \sqrt{\frac{2}{\pi}} \left(\frac{m}{k_\text{B} T}\right)^{\frac{3}{2}} v^{2} \exp{\left(- \frac{m v^{2}}{2 k_\text{B} T} \right)} - :doc:`(doc) ` Statistical weight of macrostate .. math:: \Omega = \sum_i {N}_{i}! \prod_i {N}_{i}!^{-1} - :doc:`(doc) ` Velocity component distribution .. math:: f(v_{k)} = \sqrt{\frac{m}{2 \pi k_\text{B} T}} \exp{\left(- \frac{m v_{k}^{2}}{2 k_\text{B} T} \right)} - :doc:`(doc) ` :code:`laws.thermodynamics.relativistic` .. toggle:: - :doc:`(doc) ` Reduced temperature in Maxwell—Jüttner statistics .. math:: \theta = \frac{k_\text{B} T}{m c^{2}} - :doc:`(doc) ` :code:`laws.waves` .. toggle:: - :doc:`(doc) ` Average power of sinusoidal wave on stretched string .. math:: P = \frac{\mu v \omega^{2} u_\text{max}^{2}}{2} - :doc:`(doc) ` Displacement in interfering waves .. math:: u = 2 u_\text{max} \cos \left( \frac{\varphi}{2} \right) \sin \left( k x - \omega t + \frac{\varphi}{2} \right) - :doc:`(doc) ` Displacement in standing wave .. math:: u = 2 u_\text{max} \sin(k x) \cos(\omega t) - :doc:`(doc) ` Frequency shift from speed in arbitrary motion .. math:: f_\text{o} = \frac{f_\text{s} \left(v - v_\text{o} \cos{\left(\theta_\text{o} \right)}\right)}{v - v_\text{s} \cos{\left(\theta_\text{s} \right)}} - :doc:`(doc) ` Frequency shift from speed in collinear motion .. math:: f_\text{o} = \frac{f_\text{s} \left(v - v_\text{o}\right)}{v + v_\text{s}} - :doc:`(doc) ` Fully constructive interference condition .. math:: \varphi = 2 \pi N - :doc:`(doc) ` Fully destructive interference condition .. math:: \varphi = \left(1 + 2 N\right) \pi - :doc:`(doc) ` Group velocity from dispersion relation .. math:: v_\text{g} = \frac{d}{d k} \omega{\left(k \right)} - :doc:`(doc) ` Intensity of sound wave via displacement amplitude .. math:: I = \frac{\rho v \omega^{2} s_\text{max}^{2}}{2} - :doc:`(doc) ` Light frequency change is proportional to gravitational potential change .. math:: \frac{df}{f} = - \frac{d \phi}{c^{2}} - :doc:`(doc) ` Peak wavelength via temperature .. math:: \lambda_\text{peak} = \frac{b}{T} - :doc:`(doc) ` Phase of traveling wave .. math:: \varphi = k x - \omega t - :doc:`(doc) ` Phase shift between two points .. math:: \varphi = \frac{2 \pi d}{\lambda} - :doc:`(doc) ` Phase speed of wave on stretched string .. math:: v = \sqrt{\frac{T}{\mu}} - :doc:`(doc) ` Phase speed from angular frequency and wavenumber .. math:: v = \frac{\omega}{k} - :doc:`(doc) ` Photoelectron energy from photon energy .. math:: K_\text{max} = E - W - :doc:`(doc) ` Photon energy is proportional to angular frequency .. math:: E = \hbar \omega - :doc:`(doc) ` Photon energy is proportional to linear frequency .. math:: E = h f - :doc:`(doc) ` Photon momentum is proportional to angular wavenumber .. math:: p = \hbar k - :doc:`(doc) ` Photon momentum is proportional to energy .. math:: p = \frac{E}{c} - :doc:`(doc) ` Position of antinodes in standing wave .. math:: x = \frac{\left(N + \frac{1}{2}\right) \lambda}{2} - :doc:`(doc) ` Position of nodes in standing wave .. math:: x = \frac{N \lambda}{2} - :doc:`(doc) ` Pressure amplitude in sound wave .. math:: (\Delta p)_\text{max} = v \rho \omega s_\text{max} - :doc:`(doc) ` Refractive index via permittivity and permeability .. math:: n = \sqrt{\varepsilon_\text{r} \mu_\text{r}} - :doc:`(doc) ` Resonant frequencies of stretched string with fixed ends .. math:: f = \frac{N v}{2 l} - :doc:`(doc) ` Sine of Mach cone angle via Mach number .. math:: \sin{\left(\varphi \right)} = \frac{1}{\text{M}} - :doc:`(doc) ` Speed of light via vacuum permittivity and permeability .. math:: c = \frac{1}{\sqrt{\varepsilon_0 \mu_0}} - :doc:`(doc) ` Speed of sound via bulk modulus and density .. math:: v = \sqrt{\frac{K}{\rho}} - :doc:`(doc) ` General solution to wave equation in one dimension .. math:: u = f{\left(\varphi \right)} - :doc:`(doc) ` Wavelength from phase speed and period .. math:: \lambda = v T - :doc:`(doc) ` Wavelength of standing wave in string with fixed ends .. math:: \frac{N \lambda}{2} = l - :doc:`(doc) ` Wave speed from medium permittivity and permeability .. math:: v = \frac{c}{\sqrt{\varepsilon_\text{r} \mu_\text{r}}} - :doc:`(doc) ` Wave speed from medium .. math:: v = \frac{c}{n} - :doc:`(doc) ` :code:`laws.waves.blackbody_radiation` .. toggle:: - :doc:`(doc) ` Spectral energy density at all frequencies .. math:: w_{f} = \frac{8 \pi h f^{3}}{c^{3}} \frac{1}{\exp{\left(\frac{h f}{k_\text{B} T} \right)} - 1} - :doc:`(doc) ` Spectral energy density at high frequency limit .. math:: w_{f} = \frac{8 \pi h f^{3}}{c^{3}} \exp{\left(- \frac{h f}{k_\text{B} T} \right)} - :doc:`(doc) ` Spectral energy density at low frequency limit .. math:: w_{f} = \frac{8 \pi f^{2} k_\text{B} T}{c^{3}} - :doc:`(doc) ` :code:`laws.waves.relativistic` .. toggle:: - :doc:`(doc) ` Frequency shift from speed and angle .. math:: f_\text{o} = \frac{f_\text{s} \sqrt{c^{2} - v^{2}}}{c - v \cos{\left(\varphi \right)}} - :doc:`(doc) ` Longitudinal frequency shift from speeds .. math:: f_\text{o} = \frac{f_\text{s} \left(1 - \frac{v_\text{o}}{v}\right)}{1 + \frac{v_\text{s}}{v}} \sqrt{\frac{1 - \left(\frac{v_\text{s}}{c}\right)^{2}}{1 - \left(\frac{v_\text{o}}{c}\right)^{2}}} - :doc:`(doc) ` Longitudinal frequency shift from speed .. math:: f_\text{o} = f_\text{s} \sqrt{\frac{c - v}{c + v}}