The radiation energy density per unit wavelength at a temperature $T$ has a maximum at a wavelength $\lambda_0$. At temperature $2T$,it will have a maximum at a wavelength:

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:

The variation of radiant energy emitted by the Sun, the filament of a tungsten lamp, and a welding arc as a function of its wavelength is shown in the figure. Which of the following options is the correct match?

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?

$A$ black body radiates power $P$ and maximum energy is radiated by it at a wavelength $\lambda_0$. The temperature of the black body is now changed such that it radiates maximum energy at the wavelength $\frac{\lambda_0}{4}$. The power radiated by it at the new temperature is (in $P$)

Two identical balls $A$ and $B$ are heated. Ball $A$ appears blue and ball $B$ appears red. What is the relationship between their temperatures?