The efficiency of cycle is η=1−T1T2 for adiabatic process TV r−1= constant For diatomic gas γ=57 T1 V1γ−1=T2 V2γ−1 T1=T2( V1V2)γ−1 T1=T2(32)57−1=T2(25)2/5=T2×4 T1=4 T2.η=(1−41)=43=0.75
JEE Main 2010 — Physics Thermodynamics
A diatomic ideal gas is used in a Car engine as the working substance. If during the adiabatic expansion part of the cycle, volume of the gas increases from V to 32 V the efficiency of the engine is
Held on 30 Apr 2010 · Verified 6 Jul 2026.
0.5
0.75
0.99
0.25
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