Transmission Of Heat Question 204
Question: An object is at a temperature of $ 400^{o}C $ . At what temperature would it radiate energy twice as fast? The temperature of the surroundings may be assumed to be negligible
[MP PMT 1990; DPMT 2002]
Options:
A) $ 200^{o}C $
B) $ 200\ K $
C) $ 800^{o}C $
D) 800 K
Show Answer
Answer:
Correct Answer: D
Solution:
$ \frac{E _{2}}{E _{1}}={{( \frac{T _{2}}{T _{1}} )}^{4}} $
Therefore $ \frac{2}{1}={{( \frac{420+273}{T} )}^{4}} $
$ ={{( \frac{673}{T} )}^{4}} $
Therefore $ T={{2}^{1/4}}\times 673 $ = 800K.
BETA
