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Question
An ideal gas goes from the state i to the state f as shown in figure. The work done by the gas during the process ______________ .

Options
is positive
is negative
is zero
cannot be obtained from this information
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Solution
is zero
Work done by the gas during the process,
ΔW = P Δ V
Here,
P = Pressure
ΔV = change in volume
Since the process described in the figure is isochoric, P = kT. As volume remains constant (ΔV = 0), ΔW = 0.
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