Experimental investigations show that the intensity of solar radiation is maximum for a wavelength $480 \, nm$ in the visible region. Estimate the surface temperature of the sun. Given Wien's constant $b = 2.88 \times 10^{-3} \, mK$.

The wavelength of radiation emitted from a body depends on .......

$A$ black body radiates power $P$ and maximum energy is radiated by it at a wavelength $\lambda_0$. The temperature of the black body is now changed such that it radiates maximum energy at the wavelength $\frac{\lambda_0}{4}$. The power radiated by it at the new temperature is (in $P$)

The plots of intensity versus wavelength for three black bodies at temperatures $T_1$,$T_2$ and $T_3$ respectively are as shown. Their temperatures are such that

$A$ black body has a maximum wavelength $\lambda_{m}$ at a temperature of $2000 \ K$. Its maximum wavelength at $3000 \ K$ will be:

Two stars $P$ and $Q$ are observed at night. Star $P$ appears reddish while star $Q$ is white. From this we conclude: