Question

The refractive index of glass is $1.5$ for light waves of $\lambda = 6000 \,?$ in vacuum. Its wavelength in glass is

• A. $2000 ?$
• B. $4000 ?$
• C. $1000 ?$
• D. $3000 ?$

Answer 1

Answer: (B)

$4000 ?$

Answer 2

$\mu = \frac{c}{v} = \frac{\lambda_{v}}{\lambda_{g}}$ $\therefore\lambda_{g} = \frac{\lambda_{v}}{\mu}$ $=\frac{6000}{1.5} = 4000 ?$