Two spheres of the same material have radii 1 m and 4 m and temperatures 4000 K and 2000 K respectively. The ratio of the energy rediated per second by the first sphere to that by the second is :

Options

A. `1:1`
B. `4:1`
C. `16:1`
D. `1:9`

Answer

A

Explanation

`(E_(1))/(E_(2))=(A_(1))/(A_(2))*((T_(1))/(T_(2)))^(4)=(4pir_(1)^(2))/(4pir_(2)^(2))*((T_(1))/(T_(2)))^(4)=(1/2)^(2)*((4000)/(2000))^(4)=1`
Correct choice is (a).