Calculate the elastic potential energy stored in the spring.

Question

A spring of natural length 40cm requires a force of 240N to stretch it to a length of 60cm. How much elastic potential energy would be stored in the spring if it was stretched to 70cm?

Answer 1

Hey Sabah,

First, remember that your "x" in your spring formulas refers to the change in length from its "natural length". So, the first situation would have an x of 0.20 m. You can use the first situation with Hooke's law to determine the k value for your spring. Then, you can use your formula for elastic potential energy to determine how much energy it has for the second stretch.