When $170 \text{ J}$ of energy is incident on a surface of a body, $17 \text{ J}$ of energy is reflected by it. If the coefficient of absorption is $0.7$, then the amount of energy transmitted will be (in $\text{ J}$)

At a certain temperature for a given wavelength,the ratio of the emissive power of a body to the emissive power of a black body in the same circumstances is known as:

$A$ hot and a cold body are kept in a vacuum,separated from each other. Which of the following causes a decrease in the temperature of the hot body?

If between wavelength $\lambda$ and $\lambda + d\lambda$,$e_\lambda$ and $a_\lambda$ are the emissive and absorptive powers of a body,respectively,and $E_\lambda$ is the emissive power of a perfectly black body,then according to Kirchhoff's law,which of the following is true?

According to Kirchhoff's law,the ratio of emissive power to absorptive power for all bodies is:

$A$ perfectly black body is placed in an enclosure (furnace) at room temperature. Then: