Basic (Symbols)

Symbols of fundamental physical quantities.

any_quantity

A quantity that can have any dimension.

Symbol:

X

Latex:

\(X\)

Dimension:

any_dimension

time

Time is a scalar physical quantity operationally defined as the reading of a clock, specifically a count of repeating events such as the SI second. It is a fundamental concept used to define other physical quantities.

Symbol:

t

Latex:

\(t\)

Dimension:

time

period

Period is the duration of time of one cycle in a repeating event.

Symbol:

T

Latex:

\(T\)

Dimension:

time

mass

Mass is an intrinsic scalar property of a body, and one can distinguish at least seven different aspects of mass that define it. Experiments have shown that these values are proportional, and in some cases equal. Often, the inertial mass is being used, which is a measure of the object’s resistance to acceleration when a force is applied.

Symbol:

m

Latex:

\(m\)

Dimension:

mass

molar_mass

Molar mass is defined as the mass per unit amount of substance.

Symbol:

M

Latex:

\(M\)

Dimension:

mass/amount_of_substance

work

Work is the energy transferred to or from an object via the application of force.

Symbol:

W

Latex:

\(W\)

Dimension:

energy

energy_density

Energy per unit volume.

Symbol:

w

Latex:

\(w\)

Dimension:

energy/volume

spectral_energy_density

Energy per unit volume per unit linear frequency.

Symbol:

w_f

Latex:

\(w_{f}\)

Dimension:

energy/(frequency*volume)

energy

Energy is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light.

Symbol:

E

Latex:

\(E\)

Dimension:

energy

specific_energy

Specific energy is defined as energy per unit mass.

Symbol:

epsilon

Latex:

\(\varepsilon\)

Dimension:

energy/mass

power

Power is the amount of energy transferred or converted per unit time.

Symbol:

P

Latex:

\(P\)

Dimension:

power

radius_of_curvature

Radius of curvature is the inverse of curvature and is equal to the distance to the center of curvature.

Symbol:

r

Latex:

\(r\)

Dimension:

length

density

Density is mass per unit volume.

Symbol:

rho

Latex:

\(\rho\)

Dimension:

mass/volume

linear_density

Linear density is mass per unit length.

Symbol:

mu

Latex:

\(\mu\)

Dimension:

mass/length

intensity

Intensity or flux of radiant energy is the power transferred per unit area, where the area is measured on the plane perpendicular to the direction of propagation of the energy.

Symbol:

I

Latex:

\(I\)

Dimension:

power/area

whole_number

A dimensionless whole number of any sign.

Symbol:

N

Latex:

\(N\)

Dimension:

dimensionless

positive_number

A dimensionless whole number used for counting objects or instances.

Symbol:

N

Latex:

\(N\)

Dimension:

dimensionless

nonnegative_number

A dimensionless non-negative whole number, i.e. \(0, 1, 2, \dots\).

Symbol:

N

Latex:

\(N\)

Dimension:

dimensionless

number_density

Number density is an intensive quantity used to describe the degree of concentration of countable objects (particles, molecules, phonons, cells, galaxies, etc.) in physical space.

Symbol:

n

Latex:

\(n\)

Dimension:

1/volume

particle_count

Number of particles in the system.

Symbol:

N

Latex:

\(N\)

Dimension:

dimensionless

angle

An angle is the difference in direction between two lines or surfaces.

Symbol:

phi

Latex:

\(\varphi\)

Dimension:

angle

probability

Probability is a measure of an event’s likelihood.

Symbol:

P

Latex:

\(P\)

Dimension:

dimensionless

fractional_change

Fractional change is linear change divided by initial value of the quantity.

Symbol:

e

Latex:

\(e\)

Dimension:

dimensionless

exponential_decay_constant

Exponential decay constant, also called rate constant or disintegration constant, is the rate at which some quantity is decreasing in such a way that its rate of change is proportional to its current value.

Links:

1. Exponential decay.

Symbol:

lambda

Latex:

\(\lambda\)

Dimension:

1/time

characteristic_length

Characteristic length is a dimension that defines the scale of the physical system. It is usually defined as the volume of the system divided by its surface.

Links:

1. Wikipedia.

Symbol:

l_c

Latex:

\(l_\text{c}\)

Dimension:

length

molar_volume

Molar volume is defined as volume per unit amount_of_substance.

Symbol:

v_m

Latex:

\(v_\text{m}\)

Dimension:

volume/amount_of_substance