Two spherical bodies, A(radius 6cm) and B(radius 18cm) are at temperature `T_1 and T_2`, respectively. The maximum intensity in the emission spectrum of A is at 500nm and in that of B is at 1500nm. Considering them to be black bodies, what will be the ratio of the rate of total energy radiated by A to that of B?

Explanation

`Rate of total energy radiated by A/Rate total energy radiated by B`
`(sigmaT_1^4(4pir_1^2))/(sigmaT_2^4(4pir_2^2))=((T_1)/(T_2))^4xx((r_1)/(r_2))^2`
`=((lambda_(m_2)/(lambda_(m_1))^4((r_1)/(r_2))^2 [:' (T_1)/(T_2)=(lambda_(m_2)/(lambda_(m_1) by Wein's law]`
`=(1500/500)^4(6/18)^2=9`