The refractive index of certain glass is 1.5 for light whose wavelength in vacuum is `6000Å`. The wavelength of this light when it passes through glass is:

Options

A. `4000Å`
B. `6000 Å`
C. `9000 Å`
D. `15000 Å`

Answer

A

Explanation

As we know,
`mu = c/v = (n lambda_1)/(n lambda_2) ` (Frequency remains same in all medium)
`therefore mu = (lambda_1)/(lambda_2)`
`lambda_2 = (6000)/(1.5) = 4000 Å`