If temperature of black body increases from `300K` to `900K`, then the rate of energy radiation increases by

Options

A. 81
B. 3
C. 9
D. 2

Answer

a

Explanation

Acoording to Stefan.s law `rho=(E )/(t)=sigmaAeT^(4)`
So , we can write as
`(E_(2))/(E_(1))=(T_(2)/T_(1))^(4)`
`(E_(2))/(E_(1))=((900)/(300))^(4)rArr(E_(2))/(E_(1))=(3)^(4)`
`E_(2)=81E_(1)rArr(E_(2))/(E_(1))=81`