For a perfect black body,the absorption coefficient is

If $150 \,J$ of energy is incident on an area of $2 \,m^{2}$. If $Q_{r}=15 \,J$ and the coefficient of absorption is $0.6$,then the amount of energy transmitted is: (in $\,J$)

The graph shows the blackbody radiation curves at temperatures $T_1$ and $T_2$. Which of the following is correct? $(T_2 > T_1)$

Three identical metal spheres (of same surface area) have red,black,and white colors and they are heated up to the same temperature. They are allowed to cool. Arrange them from maximum rate of cooling to minimum rate of cooling.

$A$ body,which emits radiations of all possible wavelengths,is known as ...........

$Assertion :$ $A$ body that is a good radiator is also a good absorber of radiation at a given wavelength.
$Reason :$ According to Kirchhoff's law,the absorptivity of a body is equal to its emissivity at a given wavelength.