Question

The temperature of the black body increases from T to $2$T. The factor by which the rate of emission will increases is?

• A. $4$
• B. $2$
• C. $16$
• D. $8$

Answer 1

Answer: (C)

$16$

$E=\sigma T^4$
$T_1=T$, $T_2=2T$
$\frac{E_1}{E_2}=\frac{T_1^4}{T_2^4}={\left(\frac{T}{2T}\right)}^4=\frac{1}{16}$
$E_2=16$E.