A black body at $227℃$ radiates heat at the rate of $7\ Cal/cm^{2}s$. At a temperature of $727℃$, the rate of heat radiated in the same units will be

Question

Dr. Abubacker · Accepted Answer

(c) $E \propto T^{4} \Rightarrow \frac{E_{1}}{E_{2}} = \left( \frac{T_{1}}{T_{2}} ight)^{4} \Rightarrow \frac{7}{E_{2}} = \left( \frac{273 + 227}{273 + 727} ight)^{4} = \frac{1}{16}$
$\Rightarrow E_{2} = 112\frac{cal}{cm^{2} 	imes \sec}$

Q. A black body at $227℃$ radiates heat at the rate of $7\ Cal/cm^{2}s$. At a temperature of $727℃$, the rate of heat radiated in the same units will be

Explanation

Reviewed by Dr. Abubacker

Want more practice?