A pond appears to be 2.7 m deep. If the refractive index of water is 4/3, find the actual depth of the pond.

Given,

apparent depth = 2.7 m

Refractive index of the water = $\frac{4}{3}$

Refractive index of the liquid = $\frac{\text{Actual depth}}{\text{Apparent depth}}$

Substituting the values we get,

$$\begin{aligned}\frac{4}{3} = \frac{\text{Actual depth}}{2.7} \\[0.5em] \Rightarrow \text{Actual depth} = \frac{4}{3} \times 2.7 = 3.6 \text{ m}\end{aligned}$$

Hence, actual depth = 3.6 m