A solid cube of side a density d and specific heat s is at temperature 400 K it is placed in an ambient temperature of 200 K take `a=0.9m,d=4.8xx10^(3)kg//m^(3),s=2.0xx10^(3)J//kg//K` stefan's constant `sigma=6xx10^(-8)W//K^(4)-m^(2)` consider the cube to be a blakc body. if the time for the temperature of the cube to drop by 5 K is 1000 X seconds, find X in nearest integer.

Explanation

`sigma(T^(4)-T_(S)^(4)).(6a^(2))t=(d.a^(3))s.triangleT`
`impliest=("das"triangleT)/(6.sigma(T^(4)-T_(S)^(4)))=(4.8xx10^(3)xx0.9xx2.0xx10^(3)xx5)/(6xx6xx10^(-8)xx(400^(4)-200^(4)))=5000s`.