Transmission Of Heat Question 208
Question: If temperature of a black body increases from $ 7^{o}C $ to $ 287^{o}C $ , then the rate of energy radiation increases by
[AIIMS 1997; Haryana PMT 2000; RPMT 2003]
Options:
A) $ {{( \frac{287}{7} )}^{4}} $
B) 16
C) 4
D) 2
Show Answer
Answer:
Correct Answer: B
Solution:
For a block body rate of energy $ \frac{Q}{t}=P=A\sigma T^{4} $
Therefore $ P\propto T^{4} $
Therefore $ \frac{P _{1}}{P _{2}}={{( \frac{T _{1}}{T _{2}} )}^{4}}={{{ \frac{(273+7)}{(273+287)} }}^{4}}=\frac{1}{16} $
BETA
