Question

If light incident in air at an angle of incidence 45° and refracted in other medium at an angle of refraction 30°. If wavelength in air is λ1 and frequency is v1 and in medium wavelength is λ2 and frequency is v2, then correct possible options are:

• A. $\lambda _{1}=\frac{\lambda _{2}}{\sqrt{2}},v_{1}=v_{2}$
• B. $\lambda _{1}=\lambda _{2},v_{1}=\frac{v_{2}}{\sqrt{2}}$
• C. $\lambda _{1}=\lambda _{2},v_{2}=v_{1}$
• D. $\lambda _{2}=\frac{\lambda _{1}}{\sqrt{2}},v_{2}=v_{1}$

Answer 1

Answer: (D)

$\lambda _{2}=\frac{\lambda _{1}}{\sqrt{2}},v_{2}=v_{1}$

Answer 2

$1 sin 45^{o}=\mu sin30^{o}$
$\mu=\sqrt{2}$
$\lambda _{2}=\frac{\lambda _{1}}{\sqrt{2}}$ and the frequency does not change along with the medium.

So, the correct answer is (D): $\lambda _{2}=\frac{\lambda _{1}}{\sqrt{2}},v_{2}=v_{1}$