(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I already solved Part A so just ignore that. Basically part B is saying that the ramp is no longer frictionless and has a kinetic coefficient of friction of 0.30. The other surfaces are still frictionless. It wants me to figure out how much work is done ON the block by the friction force as it slides up the ramp to the platform

2. Relevant equations

Wk = F * s

3. The attempt at a solution

Looking at the diagram I can see that there is a Normal force on the ramp, correct? So my Force should be the coeff. of kinetic friction X Normal force and nothing else. Normal force = m*g*cosθ

So I get Muk * mg * cosθ to get my Force. If this is correct can someone clarify as to why it's cosθ? I just kind of assumed that's what it is but I don't know why it actually is.

Ok so after that I still need my "s" to multiply with my Force to get the Work but I don't know how to get it.

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# Homework Help: Another Conversation of Energy Problem

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