2 masses connected by spring, one is pulled, how much does the spring stretch?

[Obliv]

Homework Statement

The masses are connected by a massless spring on a frictionless surface. One of the masses is pulled by a force F, how much does the spring stretch if at all?

Relevant Equations

F = ma, F = -kx

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Hi, I am having trouble with this problem. I'm thinking the solution is this but I'm not sure. Fnet=m1a+m2aFnet=m1a+m2a , m1a=kxm1a=kx, m2a=F−kxm2a=F−kx so x=m1ak=−(m2a−F)kx=m1ak=−(m2a−F)k

 

[Obliv]

nvm

 

[kuruman]

So what answer did you finally get? Does it reduce to what you would expect in the limiting cases $m_1<<m_2$ and $m_1>>m_2$?

 

[PeroK]

... I suggest first assuming that $m_1$ is so large that it doesn't move. That gives you an easier problem to get you started.