Question

The optical path of monochromatic light is the same if it travels 2 cm thickness of glass or 2.25 cm thickness of water. If the refractive index of water is 1.33, what is the refractive index of glass?

(a) 2.5

(b) 1.5

(c) 3.5

(d) 4.5

I had been asked this question in homework.

The question is from Wave Optics topic in division Wave Optics of Physics – Class 12

Answer 1

Correct choice is (b) 1.5

For explanation I would say: Optical path = μ × Path in medium.

The optical path for glass = Optical path for water.

μg = \(\frac {(1.33 \times 2.25)}{(2.0)}\)

μg = 1.50.