Question

In biprism experiment, if the 5^th bright band with wavelength 'λ₁' coincides with the 6^th dark band with wavelength 'λ₂' then the ratio `(lambda_2/lambda_1)` is ______ 

Options

• `9/7`

• `11/10`

• `7/9`

• `10/11`

Answer 1

In the biprism experiment, if the 5^th bright band with wavelength 'λ₁' coincides with the 6^th dark band with wavelength 'λ₂' then the ratio `(lambda_2/lambda_1)` is `underline(10/11)`.

Explanation:

`y_5 = (5lambda_1D)/d`

`y_6^' = (11lambda_2D)/(2d)`

`5lambda_1 = (11lambda_2)/2`

`lambda_1/lambda_2 = 11/10`

∴ `lambda_2/lambda_1 = 10/11`