The specific heat of many solids at low temperatures varies with absolute temperature T according to the relation `S=AT^(3)`, where A is a constant. The heat energy required to raise the temperature of a mass m of such a solid from T = 0 to T = 20 K is

Options

A. `4xx10^(4)mA`
B. `2xx10^(3)mA`
C. `8xx10^(6)mA`
D. `2xx10^(6)mA`

Answer

A

Explanation

`theta=int_(0)^(20)msdT=mAint_(0)^(20)T^(3)dT=mA((20)^(4))/(4)=4xx10^(4)mA`