Entropy change in reversible process
====================================

The second law of thermodynamics applied to a closed system and an idealized, reversible or quasistatic process,
states that in such a process of transfer of energy as heat to closed thermodynamic system :math:`B`, which
allows energy but not matter exchanges, from an auxiliary thermodynamic system :math:`A`, an infinitesimal
increment in the entropy of system :math:`B` is defined to result from an infinitesimal transfer of heat to
system :math:`B` divided by the common thermodynamic temperature of systems :math:`A` and :math:`B`.

**Notation:**

#. :math:`\delta` (:code:`delta`) denotes an inexact, path-dependent differential.
#. :math:`d` denotes an exact, path-independent differential.

**Notes:**

#. Also applicable to actually possible quasi-static irreversible processes without composition change

**Links:**

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

.. py:currentmodule:: symplyphysics.laws.thermodynamics.entropy_change_in_reversible_process

.. py:data:: entropy_change

    Infinitesimal change in :attr:`~symplyphysics.symbols.thermodynamics.entropy` of system :math:`B`.

Symbol:
    :code:`dS`

Latex:
    :math:`dS`

Dimension:
    :code:`energy/temperature`


.. py:data:: heat_supplied_to_system

    Infinitesimal amount of :attr:`~symplyphysics.symbols.thermodynamics.heat` transferred to system :math:`B`.

Symbol:
    :code:`delta(Q)`

Latex:
    :math:`\delta Q`

Dimension:
    :code:`energy`


.. py:data:: common_temperature

    Common :attr:`~symplyphysics.symbols.thermodynamics.temperature` of systems :math:`A` and :math:`B`.

Symbol:
    :code:`T`

Latex:
    :math:`T`

Dimension:
    :code:`temperature`


.. py:data:: law

    :code:`dS = delta(Q) / T`


    Latex:
        .. math::
            dS = \frac{\delta Q}{T}