Question

calculate the critical angle of water if the velocity of light in water is 2.2×10^8m/s. ( given, velocity of light in air = 3× 10^8m/s​

Answer 1

Speed of light in vacuum = 3.0 × 10⁸ m/s

Speed of light in water = 2.25 x 10⁸  m/s

Refractive index of water = ?

We know that  

Refractive index of water = $\frac{Speedoflightinvacuum}{speedoflightinwater}$

Refractive index of water =  $\frac{3*10^{8} }{2.25*10^{8} } =1.33$