A black body at a temperature of $1640 K$ has the wavelength corresponding to maximum emission equal to $1.75$ $\mu $. Assuming the moon to be a perfectly black body, the temperature of the moon, if the wavelength corresponding to maximum emission is $ 14.35$ $\mu $ is ...... $K$
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(c) $\frac{{{T_2}}}{{{T_1}}} = \frac{{{\lambda _{{m_1}}}}}{{{\lambda _{{m_2}}}}} = \frac{{1.75}}{{14.35}} \Rightarrow {T_2} = \frac{{1.75}}{{14.35}} \times 1640 = 200\;K$
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