Energy is being emitted from the surface of a black body at $127\,^{\circ}C$ temperature at the rate of $1.0 \times 10^6\,J/s\cdot m^2$. The temperature of the black body at which the rate of energy emission is $16.0 \times 10^6\,J/s\cdot m^2$ will be ......... $^{\circ}C$.

The energy spectrum of a black body has maximum energy at a wavelength of $\lambda_0$. Now, the temperature of the black body is increased such that the maximum energy is obtained at a wavelength of $3\lambda_0/4$. By what factor will the power radiated by the black body increase?

$A$ solid copper sphere of density $\rho$,specific heat capacity $C$ and radius $r$ is initially at $200 \ K$. It is suspended inside a chamber whose walls are at $0 \ K$. The time required (in $\mu s$) for the temperature of the sphere to drop to $100 \ K$ is ( $\sigma$ is Stefan's constant and all the quantities are in $SI$ units.)

If the temperature of the Sun gets doubled, the rate of energy received on the Earth will increase by a factor of

If the temperature of the sun (black body) is doubled,the rate of energy received on earth will be increased by a factor of

Calculate the surface temperature of the planet,if the energy radiated by unit area in unit time is $5.67 \times 10^4 \, W$. (Assume the planet to be a black body).