If 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

The temperature of a furnace is $2000^\circ C$ and the wavelength of maximum intensity in its spectrum is $4000 \ \mathring{A}$. If the wavelength of maximum intensity is $2000 \ \mathring{A}$, calculate the temperature of the furnace in $^\circ C$.

$A$ black body has a maximum wavelength of $\lambda_m$ at a temperature of $2000 \ K$. What will be the maximum wavelength at a temperature of $3000 \ K$?

On increasing the temperature of a substance gradually, which of the following colours will be noticed by you?

The maximum wavelength of radiation emitted by a star is $289.8 \ nm$. The intensity of radiation for the star is (Given: Stefan's constant $\sigma = 5.67 \times 10^{-8} \ W \ m^{-2} \ K^{-4}$,Wien's constant $b = 2898 \ \mu m \ K$)

$A$ black body radiates maximum energy at wavelength $\lambda$ and its emissive power is $E$. Now,due to a change in the temperature of that body,it radiates maximum energy at wavelength $\frac{2 \lambda}{3}$. At that temperature,the emissive power is: