Question

If frequency of light is $5 \times 10^{16} Hz$ and speed of light in air is $3 \times 10^{8} m / s$. Then find ratio of wavelength of light in medium of refractive index of $2$ to wavelength of light in air.

• A. $\frac{1}{2}$
• B. 3
• C. $\frac{3}{2}$
• D. 2

Answer 1

Answer: (A)

If a light travels from medium (1) to medium
(2), then, $1 \mu_{2}=\frac{\mu_{2}}{\mu_{1}}=\frac{\lambda_{1}}{\lambda_{2}}=\frac{v_{1}}{v_{2}}$
Here, $\mu_{2}=2, \mu_{1}=1$
So, $\lambda_{2} / \lambda_{1}=1/2$