Initial momentum equals final momentum
======================================

If no external force is applied to a system of objects, the total momentum of the
system remains constant during and after any interactions between objects. See
:ref:`Momentum is constant`.

**Conditions:**

#. The system is closed.

**Links:**

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

..
    TODO: rename file

.. py:currentmodule:: symplyphysics.laws.conservation.initial_momentum_equals_final_momentum

.. py:data:: initial_time

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

Symbol:
    :code:`t_0`

Latex:
    :math:`t_{0}`

Dimension:
    :code:`time`


.. py:data:: final_time

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

Symbol:
    :code:`t_1`

Latex:
    :math:`t_{1}`

Dimension:
    :code:`time`


.. py:data:: momentum

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

Symbol:
    :code:`p(t)`

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

Dimension:
    :code:`momentum`


.. py:data:: law

    :code:`p(t_1) = p(t_0)`


    Latex:
        .. math::
            p{\left(t_{1} \right)} = p{\left(t_{0} \right)}