The integral form of the first law of thermodynamics, also known as the energy conservation equation, relates the change in internal energy of a system to the heat and work interactions it undergoes. In integral form, it can be expressed as:
∆U = Q - W
where:
- ∆U represents the change in internal energy of the system.
- Q represents the net heat transferred to the system.
- W represents the net work done by the system.
This equation states that the change in internal energy (∆U) of a system is equal to the net heat (Q) added to the system minus the net work (W) done by the system. The signs conventionally follow the convention that heat transferred to the system and work done by the system are positive, while heat transferred from the system and work done on the system are negative.