The minimum temperature of a body at which it emits visible light is approximately.......$^oC$.

Two stars $A$ and $B$ radiate maximum energy at wavelengths $3.9 \times 10^{-7} \text{ m}$ and $5.2 \times 10^{-7} \text{ m}$ respectively. The ratio of the temperature of star $A$ to that of star $B$ will be

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

The wavelength of maximum energy,released during an atomic explosion,was $2.93 \times 10^{-10} \ m$. Given that the Wien's constant is $2.93 \times 10^{-3} \ m \ K$,the maximum temperature attained must be of the order of

In determining the temperature of a distant star,one makes use of

If at temperature $T_1 = 1000 \ K,$ the wavelength is $1.4 \times 10^{-6} \ m,$ then at what temperature in $K$ will the wavelength be $2.8 \times 10^{-6} \ m$?