Question

The intensity of radiation emitted by the sun has its maximum value at a wavelength $510\text{nm}$ and that emitted by another star has the maximum value at $350\text{nm}$. If we treat them as black bodies, then the ratio of the surface temperature of the sun and the star is

• A. $0.69$
• B. $1.46$
• C. $1.21$
• D. $0.83$

Answer 1

The correct option is A $0.69$

Using Wein's law, $\lambda T=\text{constant}$
$T\propto \frac{1}{{\lambda }_m}$
$\Rightarrow \frac{T_{sun}}{T_{star}}=\frac{({\lambda }_m{)}_{star}}{({\lambda }_m{)}_{sum}}=\frac{350}{510}=0.69$