Question
The sun emits a light with maximum wavelength $510\, mm$ while another star $X$ emits a light with maximum wavelength of $350\, nm$. What is the ratio of surface temperature of sun and the star $X$
✓
Answer
(b)As $\lambda \propto \frac{1}{T};$ so $\frac{{{T_1}}}{{{T_2}}} = \frac{{{\lambda _2}}}{{{\lambda _1}}} = \frac{{350}}{{510}} = 0.68$
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