SSC MTS EXAM

Detailed explanation-1: -Answer. Explanation: When a incident ray of light it is falling perpendicular to the air glass interface it means that the angle of incidence is 0°. Applying Snell’s Law at that interface: This means that the incident ray does not undergo any refraction and hence does not undergo any deviation.

Detailed explanation-2: -Light falling perpendicularly on glass slab When light falls perpendicularly or normally on the surface of a glass slab, it goes straight. There is no bending of ray of light on entering the glass slab or coming out of it. In this case angle of incidence and angle of refraction is zero.

Detailed explanation-3: -When a ray of light travelling in water, falls at right angles (90°) to the boundary of a parallel-sided glass block or travels along with the normal. The ray of light does not get refracted.

Detailed explanation-4: -A ray of light travelling in water falls at right angles to the boundary of a parallel-sided glass block. The ray of light : (a) is refracted towards the normal (b) is refracted away from the normal (c) does not get refracted (d) is reflected along the same path.