Question

Snell’s law fails when the angle of incidence is

• A. $0°$
• B. $90°$
• C. $45°$
• D. never fails

Answer 1

The correct option is A

$0°$

Explanation

1. Snell's Law states that $\frac{\sin i}{\sin r}=\frac{{\mu }_1}{{\mu }_2}$
2. This law fails when light is incident normally.
3. This is because the angle of incidence and angle of refraction both will be $0°$.
4. As we know $\sin 0°=0$ and $\frac{0}{0}$is not defined.
5. So, Snell's Law fails for $0°$.

Hence, the correct option is (A)