The pressure and density of a diatomic gas (γ=7/5) change adiabatically from (P,d) to (P',d). If (d/d') = 32, the value of (P/P') should be
1/128
32
128
none of these
P1d7/5=P′1d′7/5∴ PP′=dd′7/5=(32)7/5=257/5=27=128