Question

A ball is released from the top of a tower. What is the ratio of work done by force of gravity in first, second and third second of the motion of the ball ? [h_n α (2n – 1)] 

(A) 1 : 2 : 3 

(B) 1 : 4 : 9 

(C) 1 : 3 : 5 

(D) 1: 5 : 3

Answer 1

 Correct option: (C) 1 : 3 : 5

Explanation:

Given h

_n α (2n – 1)

W = F × s

W α s

i.e. W α h

W₁ : W₂ : W₃ = h₁ : h₂ : h₃ 

= (2 – 1) : (4 – 1) : (6 – 1)

= 1 : 3 : 5