Q131 / 155 · WBJEE 2016 · Physics
If the temperature of the Sun gets doubled, the rate of energy received on the Earth will increase by a factor of
- A2
- B4
- C8
- Correct answerD16
Solution
Suppose temperature of $\mathrm{Sun}=T$
When it is doubled, $T^{\prime}=2 T$
From law of radiation (Stefan's law)
$$
E \propto T^{4}=\sigma T^{4}
$$
$\sigma=$ Stefan's constant.
$$
\begin{array}{l}
E_{1}=T^{4} \\
E_{2} \approx(2 \Pi)^{4} \\
\frac{E_{1}}{E_{2}}=\frac{T^{4}}{2^{4} \cdot T^{4}} \\
E_{2}=16 E_{1}
\end{array}
$$
Hence, the correct answer is option: 'D'.