MCQ
If wavelengths of maximum intensity of radiations emitted by the sun and the moon are $0.5 \times {10^{ - 6}}m$ and ${10^{ - 4}}m$ respectively, the ratio of their temperatures is
- A$1/100$
- B$1/200$
- C$100$
- ✓$200$
✓
Answer
Correct option: D.
$200$
d
(d) ${\lambda _m}T$=constant ==>$\frac{{{T_1}}}{{{T_2}}} = \frac{{{\lambda _2}}}{{{\lambda _1}}}$
(d) ${\lambda _m}T$=constant ==>$\frac{{{T_1}}}{{{T_2}}} = \frac{{{\lambda _2}}}{{{\lambda _1}}}$
==>$\frac{{{{10}^{ - 4}}}}{{0.5 \times {{10}^{ - 5}}}}$ $=200$.
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