The temperature of a body is increased from $27\,^{\circ}C$ to $127\,^{\circ}C$. The radiation emitted by it increases by a factor of:

The distance between the Sun and the Earth is $2 \times 10^{8} \ km$, the temperature of the Sun is $6000 \ K$, and the radius of the Sun is $7 \times 10^{5} \ km$. If the emissivity of the Earth is $0.6$, find the temperature of the Earth in thermal equilibrium (in $K$).

In an external environment of temperature $T$ Kelvin, a sphere at temperature $3T$ Kelvin has a cooling rate $R_1$. When the temperature of that sphere falls to $2T$ Kelvin, the cooling rate of the sphere will become:

Three very large plates of the same area are kept parallel and close to each other. They are considered as ideal black surfaces and have very high thermal conductivity. The first and third plates are maintained at temperatures $2T$ and $3T$ respectively. The temperature of the middle (i.e.,second) plate under steady-state condition is

If the temperature of a hot body is increased by $50 \%$,then the increase in the quantity of emitted heat radiation will be approximately (in $\%$)

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 $= 5.67 \times 10^{-8} \ W m^{-2} K^{-4}$, Wien's constant $b = 2898 \ \mu m \ K$).