Q. The amount of heat energy radiated by a metal at temperature $T$ is $E.$ when the temperature is increased to 3T, energy radiated is
A) 81$E$
B) 9$E$
C) 3$E$
D) 27$E$
Explanation
(a) According to Stefan’s law
$E \propto T^{4}$
$\frac{E'}{E} = \left( \frac{3T}{T} \right)^{4}or\ E^{'} = 81E$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.