The maximum energy in thermal radiation from a source occurs at the wavelength $4000 \mathring A$. The effective temperature of the source is ....... $K$.

On investigation of light from three different stars $A, B$ and $C$, it was found that in the spectrum of $A$ the intensity of red colour is maximum, in $B$ the intensity of blue colour is maximum and in $C$ the intensity of yellow colour is maximum. From these observations, it can be concluded that

If $\lambda$ denotes the wavelength at which the radiative emission from a black body at a temperature $T$ is maximum, then

The energy distribution $E$ with the wavelength $\lambda$ for black body radiation at temperature $T \ K$ is shown in the figure. As the temperature is increased,the maxima will:

$A$ body at $1500 \ K$ emits maximum energy at a wavelength $20,000 \ \mathring{A}$. If the Sun emits maximum energy at a wavelength $5500 \ \mathring{A}$,then the temperature of the Sun is ....... $K$.

If the 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: