Consider two ideal diatomic gases A and B at some temperature

PHYSICS · Single correct · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics

Problem

T

. Molecules of the gas A are rigid, and have a mass

m

. Molecules of the gas B have an additional vibrational mode, and have a mass

\frac{m}{4}

. The ratio of the specific heats (

C_v^A

and

C_v^B

) of gas A and B, respectively is: (1) 7 : 9 (2) 5 : 9 (3) 3 : 5 (4) 5 : 7