The exact problem is:(adsbygoogle = window.adsbygoogle || []).push({});

A massless spring is between a 1-kilogram mass and a 3-kilogram mass, but it is not attached to either mass. Both masses are on a horizontal frictionless table. In an experiment, the 1-kilogram mass is held in place, and the spring is compressed by pushing on the 3-kilogram mass. The 3-kilogram mass is then released and moves off with a speed of 10 meters per second.

(a) Determine the minimum work needed to compress the spring in this experiment.

I am totally lost on this problem. I mean, I understand what it is asking for, but I don't know which equation to use and what variables to solve for. I know the equation for work is W= 1/2kx^2 but how do I solve for either variable?

I was looking through my notes and saw several formulas that I could use, but each one is missing the same varible, either force or the distance.

Can someone please point me in the right direction...

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# Homework Help: Work/Spring problem

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