JAMB - Physics (2000 - No. 13)
A boy observes a piece of stone at the bottom of a river 6.0m deep. If he looks from the surface of the river, what is the apparent distance of the stone from him? [Refractive Index of Water = 4/3]
8.0m
5.5m
5.0m
4.5m
Explication
Refractive Index = Real Depth/App. Depth
4/3 = 6/app. depth
App Depth = (3 x 6)/4 = 4.5m
4/3 = 6/app. depth
App Depth = (3 x 6)/4 = 4.5m