Question

A prism is an optical medium bounded by three refracting plane surfaces. A ray of light suffers successive refractions on passing through its two surfaces and deviates by a certain angle from its original path. The refractive index of the material of the prism is given by `mu = sin((A + deltam)/2)//sin  A/2`. If the angle of incidence on the second surface is greater than an angle called critical angle, the ray will not be refracted from the second surface and is totally internally reflected.

The critical angle for glass is θ₁ and that for water is θ₂. The critical angle for glass-water surface would be ______.
(given _aμ_g = 1.5, _aμ_w = 1.33)

विकल्प

• less than θ₂

• between θ₁ and θ₂

• greater than θ₂

• less than θ₁

Answer 1

The critical angle for glass is θ₁ and that for water is θ2. The critical angle for glass-water surface would be greater than θ₂.

Explanation:

`sintheta_1 = 1/mu_g; sintheta_2 = 1/mu_w`

since µ_g > µ_w, θ₁ < θ₂

The critical angle θ between glass and water will be given by, `sintheta = mu_w/mu_g ⇒ theta > theta_2`