Question

A particular star (assuming it as a black body) has a surface temperature of about $5\times 10$${}^4$ K .The wave length in nano-meters at which its radiation becomes maximum is :

( $b=$ 0.0029mK)

• A. 48
• B. 58
• C. 60
• D. 70

Answer 1

Answer: (B)

58

By Wein's displacement law, ${\lambda }_{m}T$ $=b$
So, ${\lambda }_m=\frac{b}{T}$ $=\frac{0.0029mK}{5\times {10}^{4}K}$ $=58nm$