In any given two medium, the incident angle of one medium will be called 90 degrees of the refracted angle of another medium -

Question

Question

This question was previously asked in

RPF SI (2018) Official Paper (Held On :11 Jan 2019 Shift 3)

Answer 1

The correct answer is Critical angle.

Key Points

Critical angle is defined as the angle of incidence in the denser medium for which the angle of refraction in the rarer medium is 90 degrees.
It occurs when light travels from a denser to a rarer medium, leading to total internal reflection if the incidence angle is greater than the critical angle.
The phenomenon of critical angle is crucial for devices like optical fibers, which rely on total internal reflection to transmit light.
Understanding the critical angle is also essential in fields like gemology, where it helps to explain the brilliance of diamonds and other gemstones.

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Additional Information

Option	Details
Angle of incidence	The angle formed by a ray incident on a surface and the line perpendicular to the surface at the point of incidence.
Mirror Angle	This term is not standard in optics. Typically, the angle of reflection is considered, equal to the angle of incidence in the context of mirrors.
Common Angles	This term does not specifically relate to optics or physics. It might refer to frequently used angles in various contexts, but it's not relevant to the concept of critical angle.