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Homework Statement
A mass m = 16 kg is pulled along a horizontal floor, with a coefficient of kinetic friction μk = 0.09, for a distance d = 7.6 m. Then the mass is continued to be pulled up a frictionless incline that makes an angle θ = 34° with the horizontal. The entire time the massless rope used to pull the block is pulled parallel to the incline at an angle of θ = 34° (thus on the incline it is parallel to the surface) and has a tension T = 46 N.
1)
What is the work done by tension before the block gets to the incline?
2)
What is the work done by friction as the block slides on the flat horizontal surface?
3)
What is the speed of the block right before it begins to travel up the incline?
4)
How far up the incline does the block travel before coming to rest?
5)
What is the work done by gravity as it comes to rest?
Homework Equations
The Attempt at a Solution
First and foremost, I don't need help with every question. I've already solved 1-3. My problem is that I feel I'm just doing a 'trial and error' approach. I tend to get most of these questions wrong the first time and even after getting them right I don't usually feel that I've learned anything. For example, I just did a set of problems nearly identical to this one except that the horizontal plane was frictionless. When I look back on how I solved for the distance the block traveled up the incline, I don't even know why I solved it that way or why it even works.
Specifically, I found the kinetic energy of the block right before it hit the ramp, 478 J, and used the following equation: 478 + Wt + Wg +Wf = 0
Where Wt = work done by tension
Wg = work done by gravity
Wf = work done by friction
I don't even know why I used this equation. On the very next problem (the one above) I found myself wondering why the kinetic energy (200 J) was on the left side and questioning which side it should be on and whether it should be negative or positive. In short, I feel like I have absolutely no idea what's going on and I don't know how to fix this problem.