`70` calories of heat is required to raise the temperature of `2` mole of an ideal gas at constant pressure from `30^@C` to `35^@C` . The amount of heat required to raise the temperature of the same gas through the same range at constant volume is

Options

A. 30
B. 50
C. 70
D. 90

Answer

B

Explanation

`Q_(1)=nC_(p)DeltaT`
`Q_(2)=nC_(v)DeltaT`
`(Q_(2))/(Q_(1))=(C_(v))/(C_(p))=(1)/(gamma)`
`Q_(2)=(Q_(1))/(gamma)=(70)/(1.4)=50cal`