If a force of 50N stretches a wire from 20m to 20.01m; what is the amount of force required to stretch the same material from 20m to 20.05m?

A. 250N
B. 200N
C. 100N
D. 50N

Correct Answer:

Option A – 250N

Explanation

Original length = 20m
first new length = 20.01m

First increase in length = 20.01m – 20m = 0.01m

Second new length = 20.05m

Second increase in length = 20.05 – 20m = 0.05m

From hooke’s law = F1/e1=F2/e2 ⟹50/0.01=F/20.05

⟹F2=(50×0.05)/0.01 = 250N