Initially, a gas is at a pressure of 100 kPa with a volume of 2.0 m ^3 . While keeping the pressure constant, the volume is changed from 2.0 m ^3 to 2.5 m ^3 . Subsequently, the volume is held constant and the pressure is increased from 100 kPa to 200 kPa . Finally, the gas is returned to its initial state such that the pressure varies linearly with its volume. Determine whether heat is supplied to or extracted from

Step-by-step solution

The cyclic process consists of three steps: Isobaric expansion from state A (2.0 m ^3, 100 kPa ) to state B (2.5 m ^3, 100 kPa ) . Isochoric process from state B to state C (2.5 m ^3, 200 kPa ) . Linear return from state C to state A. Plotting these states on a P-V diagram forms a right-angled triangle. The sequence A B C A traces a counter-clockwise cycle. The net work done in a counter-clockwise cycle on a P-V diagram is negative ( W From the first law of thermodynamics for a complete cycle, U = 0 , giving Q = W