Q. 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
A) $100\ K$
B) $150\ K$
C) $200\ K$
D) $250\ K$
Explanation
(c) $\frac{T_{2}}{T_{1}} = \frac{\lambda_{m_{1}}}{\lambda_{m_{2}}} = \frac{1.75}{14.35} \Rightarrow T_{2} = \frac{1.75}{14.35} \times 1640 = 200\ K$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.