Total elastic potential energy of a compressed spring?

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ErwinJL
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Homework Statement


A spring with a spring constant of 4 Newtons per meter is compressed by a force of 1.2 Newtons. What is the total elastic potential energy stored in this compressed spring?

k = 4 N/m
F = 1.2 N
PE = ?

Homework Equations


PE = (1/2)(k)(x)^2

The Attempt at a Solution


Using the information from the problem, I can use PE = (1/2)(k)(x)^2 to find the stored potential energy. I can plug in 4 N/m for k, but I am stuck with plugging in the distance compressed for x. The problem gives me the amount of force used to compress the spring, but I don't know how to find the distance compressed using it.
 
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ErwinJL said:

Homework Statement


A spring with a spring constant of 4 Newtons per meter is compressed by a force of 1.2 Newtons. What is the total elastic potential energy stored in this compressed spring?

k = 4 N/m
F = 1.2 N
PE = ?

Homework Equations


PE = (1/2)(k)(x)^2

The Attempt at a Solution


Using the information from the problem, I can use PE = (1/2)(k)(x)^2 to find the stored potential energy. I can plug in 4 N/m for k, but I am stuck with plugging in the distance compressed for x. The problem gives me the amount of force used to compress the spring, but I don't know how to find the distance compressed using it.

Are you familiar with Hooke's Law?
 
Yes, today I asked my teacher about it in class, and he explained it to me. We know the spring constant is 4 N/m and the force applied, which is 1.2 Newtons. Both are incorporated in Hooke's law(F = -kx); using it, we can solve for x by dividing the force by the spring constant, leaving .3 meters for distance compressed. Then we can use that with what we already know to find stored potential energy :biggrin:.

Thanks for the help anways