Question

The state of an ideal gas can be represented by a point on a PV (pressure-volume) diagram. If you know the quantity of gas, n, a unique point in pressure (P) and volume (V) can be used to determine a temperature (T). Each point on a PV diagram also has a single internal energy (U) assigned to it. If a process starts at a point and returns to that same point on a PV diagram, it returns to the same P, V, T, and U.

The PV diagram below shows four different states, A, B, C, and D. The lines connecting the states represent processes or transitions. For example, the line connecting states A and B represents an expansion of the gas (transition to larger volume) while the pressure is kept co

( A is the top left, B is the top right, C is the bottom right, D is the bottom left together they form a rectangle. The X axis is V and the Y axis is P)

nstant. In the case of this diagram, the pressure at states A and B is 3.80?10⁵ Pa. The pressure at states C and D is 1.44?10⁵ Pa. Likewise the volume at states A and D is 1.40?10^-3 m³ and the volume at states B and C is 4.48?10^-3 m³.

What is the work done by the gas for the transition BC?

Answer 1

An isochoric thermodynamic process is characterized by constant volume, i.e., $\Delta V = 0$ . The process does no pressure-volume work, since such work is defined by

$\Delta W = P \Delta V$