Question

The refractive index of water is 4/3. If ray travels 24 cm in air in a given time t, the distance travelled by light in water in the same time t is :

• A. $32cm$
• B. $24cm$
• C. $18cm$
• D. $15cm$

Answer 1

The correct option is C $18cm$

Using snell's law:

$\frac{sini}{sinr}=\frac{v_1}{v_2}=\frac{{\mu }_2}{{\mu }_1}$

$\frac{\frac{24}{t}}{\frac{x}{t}}=\frac{\frac{4}{3}}{1}$

$\Rightarrow x=18cm$