The wavelenght of maximum intensity of radiation emitted by a star is `289.8` nm. The radiation intensity of the star is
(Stefan's constant `= 5.67 xx 10^(-8) Wm^(-2)K^(-4)`, constant `b= 2898 mumK`)

Options

A. `5.67 xx 10^(8)W//m^(2)`
B. `5.67 xx 10^(12)W//m^(2)`
C. `10.67 xx 10^(7)W//m^(2)`
D. `10.67 xx 10^(14)W//m^(2)`

Answer

A

Explanation

By Weins law, `gamma_(m) T = b`
`T = (b)/(gamma_(m))=(2898xx10^(-6))/(289.8xx10^(-9))=1 xx 10^(4) K`
Emissive power,
`E alpha T^(4)`
`E = sigma T^(4) = 5.67 xx 10^(-8) xx (10^(4))^(4) = 5.67 xx 10^(-8) xx 10^(16)`
` = 5.67 xx 10^(8) W//m^(2)`