Im trying to understand how to approach this problem.
For the first part i got F=(0.5(M +m)v^2)/d
For the first question that is already too much. It's a trivial question about the definition of work. For the second part you should find the force acting on the plate, and again apply the definition of work.
What do you mean? I did use the definition of work to solve this
What do you need that "(0.5(M +m)v^2)" part for?
Are you not supposed to solve for F using the work formula?
You are supposed to find W, not F. And what does "(0.5(M +m)v^2)" have to do with that?
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