Two stars emit maximum radiation at wavelengths $3600 \mathring A$ and $4800 \mathring A$ respectively. The ratio of their temperatures is:

The Earth radiates in the infra-red region of the spectrum. The spectrum is correctly given by

Wien's displacement law expresses the relationship between:

The following graph represents the radiant power versus wavelength of a black body. The area under the curve represents:

Two bodies $A$ and $B$ of equal surface area have thermal emissivities of $0.01$ and $0.81$ respectively. The two bodies are radiating energy at the same rate. Maximum energy is radiated from the two bodies $A$ and $B$ at wavelengths $\lambda_A$ and $\lambda_B$ respectively. The difference in these two wavelengths is $1 \mu m$. If the temperature of body $A$ is $5802 \ K$, then the value of $\lambda_B$ is:

The energy distribution $E$ with the wavelength $\lambda$ for black body radiation at temperature $T \ K$ is shown in the figure. As the temperature is increased,the maxima will: