Question

Monochromatic light of wavelength $589nm$ is incident from air on a water surface. The refractive index of water is $1.33$. The wavelength of the refracted light is

• A. 589 nm
• B. 443 nm
• C. 333 nm
• D. 221 nm

Answer 1

Answer: (B)

The refractive index of water with respect to air
${}_a{\mu }_w=\frac{{\mu }_w}{{\mu }_a}$
$=\frac{\mu {\lambda }_{\text{air }}}{v{\lambda }_{\text{water }}}$
$\therefore \lambda$ in water $=\frac{{\lambda }_{\text{air }}}{\mu }$
$\Rightarrow \lambda$ in water $=\frac{589}{1.33}nm$
$\Rightarrow \lambda$ in water $=443nm$