The rate of cooling at `600 K`. If surrounding temperature is `300 K` is `H`. The rate of cooling at `900 K` is

Options

A. `16/3 H`
B. `2H`
C. `3H`
D. `2/3H`

Answer

A

Explanation

By Stefan's law , Rate of cooling. `H prop(T^(4)-T_(0)^(4))`
`:. (H')/(H)=((900)^(4)-(300)^(4))/((600)^(4)-(300)^(4)) = (9^(4)-3^(4))/(6^(4)-3^(4)) = (3^(4)(3^(4)-1))/(3^(4)(2^(4)-1))`
`:. H' = 16/3 H`.