Question

Given that ∠$i$ is angle of incidence and ∠$r$ is angle of refraction for a light ray at a boundary, the correct expression for Snell's Law is:

(A) $\sin i={\sin }^{2}r$

(B)$\sin i=k\sin r$
[k = constant]

(C)$\cos i=k\cos r$
[k = constant]

(D) $\sin r={\sin }^{2}i$
[1 Mark]

Answer 1

Snell’s law states that the ratio of sine of angle of incidence to the sine of angle of refraction is a constant.
$\frac{\sin i}{\sin r}=k=n_{21}$
where k is a constant. This constant is defined for the second medium with respect to the first medium.

Hence option B is correct.
[1 Mark]