Question

A spring has an spring constant, k, of of 7 N/m. How far would the spring need to stretch to contain 19.5 J of energy?

A) 68.25m

B) 5.57m

C) 2.79m

D) 2.36m

Answer 1

The correct answer is: C) 2.79m

The formula for the elastic potential energy stored in a spring is:

Elastic potential energy = (1/2) k x^2 where k is the spring constant and x is the displacement of the spring from its equilibrium position.

To find x, we can rearrange the formula as follows:

x = sqrt((2 x Elastic potential energy)/k)

Substituting the given values, we get:

x = sqrt((2 x 19.5 J)/7 N/m) = 2.79 m


Therefore, the spring would need to stretch 2.79 meters to contain 19.5 J of energy.