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Question
An ideal gas undergoes cyclic process ABCDA as shown in given P-V diagram (figure). The amount of work done by the gas is ______.
Options
6P0V0
–2P0V0
+ 2P0V0
+ 4P0V0
Solution
An ideal gas undergoes cyclic process ABCDA as shown in given P-V diagram (figure). The amount of work done by the gas is `underline(- 2P_0V_0)`.
Explanation:
Consider the P-V diagram given in the question.
Work done in the process ABCD = Area of rectangle ABCDA
= (AB) × BC
= (3V0 – V0) × (2P0 – P0)
= 2V0 × P0
= 2p0V0
As the process is going anticlockwise, hence there is a net compression in the gas. So, work done by the gas = –2P0V0.
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