An isobaric process is a thermodynamic process that occurs at constant pressure. In such processes, the volume of the substance or gas heated is allowed to vary with temperature. One example of an isobaric process is the expansion of gas to drive a freely moving piston.
Heat is transferred in an isobaric process, which increases the internal energy of the system. This increase in internal energy is used to do work. The work done by an ideal gas at a constant pressure is calculated by the equation: W = p * delta-V. W stands for the work, p is the pressure, and delta–V is the change in volume.