JAMB - Physics (1983 - No. 34)
the speed of light in vacuum is 3.0 x 108ms-1. If the refractive index of a transparent liquid is \(\frac{4}{3}\), then the speed of light in the liquid is
0.44 x 10 8ms-1
2.25 x 10 8ms-1
3.0 x 10 8ms-1
4.0 x 10 8ms-1
4.33 x 10 8ms-1
Explication
n = \(\frac{\text{speed in air }}{\text{speed in water }}\)
\(\frac{4}{3}\) = \(\frac{3 \times 10^8}{v}\)
v = 2.25 x 10 8ms-1
\(\frac{4}{3}\) = \(\frac{3 \times 10^8}{v}\)
v = 2.25 x 10 8ms-1