Ordinary (i.e., unpolarised) lights is incident on the surface of a transparent material at the polarising angle. If it is partly reflected and partly refracted, what is the angle between the reflected and the refracted rays?

Explanation

To solve the problem, we need to understand the behavior of light when it strikes the surface of a transparent material at the polarizing angle.

### Step-by-Step Solution:

1. **Identify the Polarizing Angle**: The polarizing angle (also known as Brewster's angle) is the angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with no reflection.

2. **Understand the Reflection and Refraction**: When unpolarized light hits the surface at the polarizing angle, it is partly reflected and partly refracted. The reflected light will be polarized perpendicular to the plane of incidence.

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