MCQ
Two thin parallel slits are made in an opaque screen. When a monochromatic beam of light passes through them at normal incidence, the first bright fringe in the transmitted light occurs at $\pm 45^o $ with the original direction of the light beam on a distant screen when the apparatus is in air. When the apparatus is immersed in a liquid, the same bright fringe now occurs at $\pm 30^o $. The index of refraction of the liquid is
- ✓$\sqrt 2$
- B$\sqrt 3$
- C$\frac{4}{3}$
- D$\frac{3}{2}$
