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प्रश्न
Consider two processes on a system as shown in figure.
The volumes in the initial states are the same in the two processes and the volumes in the final states are also the same. Let ∆W1 and ∆W2 be the work done by the system in the processes A and B respectively.

पर्याय
∆W1 > ∆W2
∆W1 = ∆W2
∆W1 < ∆W2
Nothing can be said about the relation between ∆W1 and ∆W2
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उत्तर
∆W1 < ∆W2
Work done by the system, ∆W = P ∆ V
here,
P = Pressure in the process
∆V = Change in volume during the process
Let Vi and Vf be the volumes in the initial states and final states for processes A and B, respectively. Then,
\[\Delta W_1 = P_1 \Delta V_1 \]
\[\Delta W_2 = P_2 \Delta V_2 \]
But \[\Delta V_2 = \Delta V_1 ,.............\left[ \left( V_{f_1} - V_{i_1} \right) = \left( V_{f_2} - V_{i_2} \right) \right]\]
\[ \Rightarrow \frac{\Delta W_1}{\Delta W_2} = \frac{P_1}{P_2}\]
\[ \Rightarrow \Delta W_1 < \Delta W_2..........\left[ \because P_2 > P_1 \right]\]
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