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

Options

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

Answer

A

Explanation

`mu_(g) = (lambda_(a))/(lambda_(g))`
`:. lambda_(g) = (lambda_(a))/(mu_(g)) = (6000)/(1.5) = 4000 Å`