In determining the temperature of a distant star,one makes use of

On observing light from three different stars $P, Q$ and $R$, it was found that the intensity of violet colour is maximum in the spectrum of $P$, the intensity of green colour is maximum in the spectrum of $R$, and the intensity of red colour is maximum in the spectrum of $Q$. If $T_P, T_Q$ and $T_R$ are the respective absolute temperatures of $P, Q$ and $R$, then it can be concluded from the above observations that:

The temperature of the sun is $5500 \ K$ and it emits maximum intensity radiation in the yellow region $(5.5 \times 10^{-7} \ m)$. The maximum radiation from a furnace occurs at a wavelength of $11 \times 10^{-7} \ m$. The temperature of the furnace is ....... $K$.

The intensity of radiation emitted by the sun has its maximum value at a wavelength of $510\;nm$ and that emitted by the north star has the maximum value at $350\;nm$. If these stars behave like black bodies,then the ratio of the surface temperature of the sun and north star is

$A$ black body emits radiation with maximum intensity at a wavelength of $5000 \mathring{A}$ at a temperature of $1227^\circ C$. If its temperature is increased by $1000^\circ C$, the new wavelength of maximum intensity will be ...... $\mathring{A}$.

If the temperature of the sun becomes twice its present temperature,then