CAPE Physics Unit 1 · 2014 · Paper 1 · Question Q23

As light travelling in air enters a medium, its speed changes to 2.4 \times 10^8\text{ m s}^{-1}. The refractive index of the medium is

1. (A)0.60
2. (B)0.80
3. (C)1.25
4. (D)1.50