Question

A boy drops a stone in a well and finds it takes 2.60 seconds to hit the water.
A) How deep is the well?
B) With what speed does the stone hit the water?

Answer 1

Answer:

(i) How deep is the well (Height)

=> t = √(2H/g)

=> √2H = t × g

=> 2H = t² × g²

=> 2H = (2.60)² × (10)²

=> 2H = 6.76 × 100

=> 2H = 676

=> H = 676 ÷ 2

=> H = 338 m

(ii) speed of the stone:

=> v = √(2Hg)

=> v = √(2 × 338 × 10)

=> v = √6760

=> v = 26√10 m/s