What will be the ratio of temperatures of the sun and the moon if the wavelengths corresponding to their maximum emission radiation rates are $140 \mathring{A}$ and $4200 \mathring{A}$ respectively?

Wien's constant is $2892 \times 10^{-6} \text{ m K}$ and the value of $\lambda_m$ from the moon is $14.46 \text{ microns}$. What is the surface temperature of the moon in $K$?

In the figure,the distribution of energy density of the radiation emitted by a black body at a given temperature is shown. The possible temperature of the black body is ....... $K$.

According to Wien's displacement law:

When an iron rod is heated, the variation of colour from dull red to white can be explained by

Three black discs $x, y, z$ have radii $1 \ m, 2 \ m$ and $3 \ m$ respectively. The wavelengths corresponding to maximum intensity are $200 \ nm, 300 \ nm$ and $400 \ nm$ respectively. The relation between emissive power $E_x, E_y$ and $E_z$ is: