The clear water of a lake is 1.5 m deep at the end of a dock.You look directly down from the end of the dock and see a rock on the bottom of the lake.How far below the surface does the rock appear to be? (For water,n = 1.33.)
A)2.0 m
B)1.5 m
C)1.1 m
D)0.75 m
E)1.8 m

Question

Quizplus · Accepted Answer

Using the formula:
apparent depth = real depth / refractive index of the medium
where real depth is 1.5 m and refractive index of water is 1.33.
So, 
apparent depth = 1.5 / 1.33 = 1.13 m
Thus, the rock appears to be 1.1 m below the surface. Therefore, the best choice is C.

The Clear Water of a Lake Is 1