If the work done to stretch an ideal spring by 4.0 cm is 6.0 J,what is the spring constant of this spring?
A)300 N/m
B)3000 N/m
C)3500 N/m
D)7500 N/m
E)6000 N/m

Question

Quizplus · Accepted Answer

The formula for the potential energy stored in a spring is U = (1/2)kx^2, where k is the spring constant and x is the displacement from equilibrium. 
We know that the work done (W) to stretch the spring by 4.0 cm is 6.0 J, which means:

W = U = (1/2)kx^2 
6.0 J = (1/2)(k)(0.04 m)^2

Solving for k:

k = (2)(6.0 J) / (0.04 m)^2 
k = 7500 N/m

Therefore, the spring constant of this ideal spring is 7500 N/m. Answer choice D is correct.

If the Work Done to Stretch an Ideal Spring by 4.0