Mechanical energy is constant
=============================

Mechanical energy is constant in a system that has only gravitational forces or in an
otherwise idealized system, that is it lacks dissipative forces, such as friction
and air resistance, or when such forces can be reasonably neglected.

**Notes:**

#. SymPy does not have a proper way to represent constant energy. We use it's derivative
   over time instead. Derivative of the constant value is zero.

**Links:**

#. `Wikipedia <https://en.wikipedia.org/wiki/Conservation_of_energy>`__.

.. py:currentmodule:: symplyphysics.laws.conservation.mechanical_energy_is_constant

.. py:data:: time

    :attr:`~symplyphysics.symbols.basic.time`.

Symbol:
    :code:`t`

Latex:
    :math:`t`

Dimension:
    :code:`time`


.. py:data:: mechanical_energy

    :attr:`~symplyphysics.symbols.classical_mechanics.mechanical_energy` as a function of :attr:`~time`.

Symbol:
    :code:`E(t)`

Latex:
    :math:`E{\left(t \right)}`

Dimension:
    :code:`energy`


.. py:data:: law

    :code:`Derivative(E(t), t) = 0`


    Latex:
        .. math::
            \frac{d}{d t} E{\left(t \right)} = 0