Question

The radiation energy density per unit wavelength at a temperature T has a maximum at a wavelength `lambda_0.` At temperature 4T, it will have a maximum at a wavelength ____________.

Options

• `4 lambda_0`

• `2lambda_0`

• `lambda_0/2`

• `lambda_0/4`

Answer 1

The radiation energy density per unit wavelength at a temperature T has a maximum at a wavelength `lambda_0.` At temperature 4T, it will have a maximum at a wavelength `lambda_0/4`.

Explanation:

According to Wien's law,

`lambda_"m" "T" = lambda'_"m" "T'"`

`therefore  lambda_0  "T" = lambda' xx 4"T" Rightarrow lambda' = lambda_0/4`