Chapter 22 - Reflection and Refraction of Light - Learning Path Questions and Exercises - Exercises - Page 775: 39

$11 cm$

By Snell's Law, $n_{a}\times sin50^{\circ}=n_{w}\times sin\theta_{r}$ or, $sin\theta_{r}=\frac{sin50^{\circ}}{1.33}=0.5759$ or, $\theta_{r}=35.17^{\circ}$ If the coin is at a distance x from the side of the container, then $x= tan35.17^{\circ} \times 15 cm=11cm$