Find the rate of radiation emitted per unit area per unit time by a black body at a temperature of $10^{3} \ K$ (in $J \ m^{-2} \ s^{-1}$).

$A$ black body at $227^o C$ radiates heat at the rate of $7 \; cal/cm^2 s$. At a temperature of $727^o C$,the rate of heat radiated in the same units will be:

The rate of radiation of a black body at $0^{\circ}C$ is $E \ J/s$. The rate of radiation of this black body at $273^{\circ}C$ will be:

$A$ body emits $5 \ W$ of energy at a temperature of $127^{\circ}C$. If the temperature is increased to $927^{\circ}C$,then the emitted energy becomes .......... $W$.

In the $MKS$ system,Stefan's constant is denoted by $\sigma$. In the $CGS$ system,the multiplying factor of $\sigma$ will be:

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: