JAMB - Physics (1983 - No. 5)
The refractive index of liquid is 1.5. If the velocity of light in vacuum is 3.0 x 108ms-1, the velocity of light in the liquid is
1.5 x 108m-1
2.0 x 108m-1
3.0 x 108m-1
4.5 x 108m-1
9.0 x 108m-1
Explication
n = \(\frac{\text{velocity of light in vacuum}}{\text{velocity of light in liquid}}\)
1.5 = \(\frac{3\times10^4}{\text{velocity of light in liquid}}\)
Velocity of light in liquid = 2 x \(10^8ms^{-1}\)
1.5 = \(\frac{3\times10^4}{\text{velocity of light in liquid}}\)
Velocity of light in liquid = 2 x \(10^8ms^{-1}\)