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
IIT 1997,AIIMS 2000, Easy
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(b) $\frac{{{T_S}}}{{{T_N}}} = \frac{{{{({\lambda _N})}_{\max }}}}{{{{({\lambda _S})}_{\max }}}} = \frac{{350}}{{510}} = 0.69$
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