Transmission Of Heat Question 227
Question: The original temperature of a black body is $ 727^{o}C. $ The temperature at which this black body must be raised so as to double the total radiant energy, is
[Pb. PMT 2001]
Options:
A) 971 K
B) 1190 K
C) 2001 K
D) 1458 K
Show Answer
Answer:
Correct Answer: B
Solution:
$ \frac{Q _{2}}{Q _{1}}={{( \frac{T _{2}}{T _{1}} )}^{4}}\Rightarrow \frac{2}{1}={{( \frac{T _{2}}{T _{1}} )}^{4}} $
$ \Rightarrow T _{2}^{4}=2\times T _{1}^{4}=2\times {{(273+727)}^{4}} $
Therefore $ T _{2}=1190K $ .
BETA
