Heat Capacity#
Heat capacity is the amount of thermal energy a system can hold per change in temperature.
\[C \equiv \left(\frac{dU}{d\tau}\right)_\text{const}\]
Heat capacity is not very useful and cannot be defined for a system that doesn’t keep either pressure (\(P\)) or volume (\(V\)) constant.
Without keeping pressure or volume constant system the energy is often transfered to work (\(dW = PdV + VdP\))