A black metal foil is warmed by radiation from a small sphere at temperature `T` and at a distance d it is found that the power received by the foil is `P` If both the temperature and the distance are doubled the power received by the foil will be .

Options

A. `1:4`
B. `1:8`
C. `1:16`
D. `1:64`

Answer

A

Explanation

`I=(esigmaAT^(4))/(d^(2))rArr(I_(2))/(I_(1))=((T_(2))/(T_(1)))^(4)xx((d_(1))/(d_(2)))^(2)hereI_(1)=P`