Question:

The speed of light in media M1 and M2 are 1.5×10⁸ m/s and 2.0×10⁸ m/s respectively. A ray of light enters from medium M1 to M2 at an incidence angle i. If the ray suffers total internal reflection, the value of i is:

Equal to sin⁻¹(23)

Equal to or greater than sin⁻¹(34)

Equal to or less than sin⁻¹(35)

Less than sin⁻¹(23)

For the given question,
sinc = c₁/c₂ = 1.5/2 = 3/4
Therefore, c = sin⁻¹(3/4)
So to suffer total internal reflection i > sin⁻¹(3/4)