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. `2 H`
C. `3H`
D. `2/3 H`

Answer

A

Explanation

By stenfan'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`