(a) A water tank appears `1*5` m deep. What is it actual depth ? Given refractive index of water w.r.t. air is `4//3`.
(b) If `1*5` m were actual depth of water tank, what would be its apparent depth?

Explanation

(a) As `n=("real depth"(x))/("apparent depth"(y)) :. x=ny=4/3xx1*5=2m`.
(b) Again, from `n=x/y`, `y=x/n=(1.5)/(4//3)=1.1m`.