Question

Critical angle will be maximum, when light travels from

• A. Glass to air
• B. Glass to water
• C. Water to air
• D. Diamond to air

Answer 1

Answer: (B)

Glass to water

Critical angle when a light travels from a medium $n_2$ to $n_1$, $\theta ={\sin }^{-1}(\frac{n_1}{n_2})$

where $n$ is the refractive index.

We know, $n_{air}=1$ $n_{water}=1.33$ $n_{glass}=1.5$ $n_{diamond}=2.4$

From this we get, $\frac{n_{water}}{n_{glass}}=0.886$ as the maximum value.

Thus critical angle will be maximum when light travels from glass to water.