An ideal diatomic gas is heated at constant pressure. The ratio of the work done to the heat supplied is

Question

An ideal diatomic gas is heated at constant pressure. The ratio of the work done to the heat supplied is (A) (3/5) (B) (2/5) (C) (2/7) (D) (4/7)

Tardigrade Admin · Accepted Answer

Heat supplied at constant pressure is Δ Q =n CpΔ T Work done by the gas, Δ W =pΔ V=nRΔ T Ratio of work done to heat supplied is (Δ W/Δ Q)=(nRΔ T/nCpΔ T) =(R/Cp)=(Cp-CV/Cp) =1-(1/&gamma;) =1-(1/(7 /5)) =1-(5/7)=(2/7)

Q. An ideal diatomic gas is heated at constant pressure. The ratio of the work done to the heat supplied is

$\frac{3}{5}$

$\frac{2}{5}$

$\frac{2}{7}$

$\frac{4}{7}$

Q. An ideal diatomic gas is heated at constant pressure. The ratio of the work done to the heat supplied is

53​

52​

72​

74​

Heat supplied at constant pressure is ΔQ=nCp​ΔT Work done by the gas, ΔW=pΔV=nRΔT Ratio of work done to heat supplied is ΔQΔW​=nCp​ΔTnRΔT​ =Cp​R​=Cp​Cp​−CV​​ =1−γ1​ =1−(7/5)1​ =1−75​=72​

$\frac{3}{5}$

$\frac{2}{5}$

$\frac{2}{7}$

$\frac{4}{7}$