T1V1γ−1=T2V2γ−1
T2=T1(V2V1)γ−1
=T1(10)57−1
T2=T1(10)2/5
ΔV=25nR;25×5×3[102/5−1](293)
6625×1.5×293=461440
≈46ks
JEE Main 2020 — Physics Thermodynamics
An engine takes in 5 moles of air at 20∘C and 1atm, and compresses it adiabatically to 1/10th of the original volume. Assuming air to be a diatomic ideal gas made up of rigid molecules, the change in its internal energy during this process comes out to be XkJ. The value of X to the nearest integer is:
Held on 2 Sept 2020 · Verified 6 Jul 2026.
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