Question

In a lake 2m deep, a measuring post of height 3m is fixed vertically. For an angle of incidence of 45° of Sun’s radiations, find the length of the shadow of the post at the bottom surface?(μ_w = 4/3) in metre

Answer 1

Now PB/AB = tan 45°

AB = 1m

Hence CD = 1m 

Now, n₁ sin45° = n₂ sinθ

Hence, shadow (EC + CD)(1m + 6/√29 m)

 = 2m