A) \[{{10}^{4}}\]
B) 625
C) 256
D) 16
Correct Answer: B
Solution :
From Stefans law, if the emissive power of a body at absolute temperature T be e, then the energy emitted by its unit area per second is \[\sigma {{T}^{4}}\times e,\], also if A is the surface area of the body, then \[E=\sigma {{T}^{4}}eA\] when \[R=100R\]and \[T=\frac{T}{2}\] then energy emitted is \[E\propto 4\pi {{(100R)}^{2}}{{\left( \frac{T}{2} \right)}^{4}}\] \[\propto {{\left( \frac{100}{4} \right)}^{2}}\times 4\pi {{R}^{2}}{{T}^{4}}\] \[\therefore \] \[E={{\left( \frac{100}{4} \right)}^{2}}\times E\] \[\therefore \] \[\frac{E}{E}=625\]
You need to login to perform this action.
You will be redirected in
3 sec
