(adsbygoogle = window.adsbygoogle || []).push({}); Kinetic and Potential Energy!?!

This problem is totally confusing me..can someone please explain it...

A 3.0 kg object subject to a restoring forceFis undergoing simple harmonic motion with a small amplitude. The potential energyUof the object as a function of distance x from its equilibrium is shown. This particular object has a total energyE: of 0.4 J.

(a) What is the object's potential energy when its displacement is +4 cm from its equilibrium position?

For this problem, I used 4 cm as my displacement, but when I used it in the formula, I ended up getting an answer that is greater than the total energy, so I know it must be wrong. Am I using the wrong displacement?

(b) What is the farthest the object moves along the x-axis in the positive direction? Explain.

I really don't understand how to solve for the distand in the x-axis without having the acceleration or time. Is there a formula that I've overlooked or am I just making this problem more complicated than it is?

(c) Determine the object's kinetic energy when its displacement is -7 cm.

For this part, the kinetic energy equation is KE= 1/2mv^2. How do I solve for the velocity without time or acceleration?

(d) What is the object's speed at x= 0?

Again, I would need the answers from (c) to solve for the speed.

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# Homework Help: Kinetic and Potential Energy?

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