Question

A beam of light passes from air into a substance $X$. If the angle of incident be ${72}^o$ and the angle of refraction be ${40}^o$, calculate the refractive index of substance $X$. (Given: $\sin {72}^o=0.951$ and $\sin {40}^o=0.642$)

Answer 1

Given that,

Angle of incident $i={72}^0$

Angle of refraction $r={40}^0$

We know that, according to Snell's law,

Refractive index is

$n=\frac{\sin i}{\sin r}$

$n=\frac{0.951}{0.642}$

$n=1.48$

Hence, the refractive index of substance is $1.48$