Q. At temperature $T$, the power radiated by a body is $Q\ watts$. At the temperature $3T$ the power radiated by it will be
A) $3\ Q$
B) $9\ Q$
C) $27\ Q$
D) $81\ Q$
Explanation
(d) Power radiated $P \propto T^{4} \Rightarrow \frac{P_{1}}{P_{2}} = \left( \frac{T_{1}}{T_{2}} \right)^{4}$
$\Rightarrow \frac{Q}{P_{2}} = \left( \frac{T}{3T} \right)^{4} \Rightarrow P_{2} = 81Q$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.