- Work done in any adiabatic (
) process is a function of state.
We can write the first law, setting the heat transfer
term equal to zero, as
depends only on the state change, now
found as a function of the state change.
The change in energy between
two states is not path dependent.
- For a cyclic process heat and work transfers are numerically equal
Since energy is a
function of state only, any process that returns a system to its
original state leaves its energy unchanged.