Problem Introducing Me to Sliding Friction

AI Thread Summary
The discussion centers on a physics problem involving a box being pulled up with a pulley, where the challenge lies in calculating the minimum force required to lift the box while accounting for sliding friction. The problem requires the use of integration techniques to derive the solution, specifically leading to the expression Weπμ. Participants emphasize understanding the relationship between friction, the forces involved, and the geometry of the pulley system. Guidance is sought on conceptualizing the problem and applying calculus effectively. The conversation highlights the importance of breaking down the components of the forces at play in the scenario.
swill777
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I'm going through the problems at the back of a chapter in my physics book where all the challenging questions are. I'm able to solve most and comprehend the rest, however, there's one that's introducing a new concept that I'm not quite sure how to think about.

Its a situation where I'm pulling a box with weight W up utilizing a pulley with radius r and a sliding friction coefficient μ. What is the minimum force on the rope downward on the rope needed to lift the box?

The question says to use an integration technique, and says to show that it's Weπμ.

I'm not quite sure how to think about this; and knowing that I need to use an integration technique to solve it is throwing me off as well.

I'm quite knowledgeable of single variable calculus and I'm not looking for an answer, I'm just looking for some help in how to think about this problem, and perhaps some guidance pointing me in a direction to go about solving this problem or dealing with this situation.

Thank you.
 
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From your description it sounds like a rope over a pully that has friction. ... weight+friction opposes the motion ... how is friction related to the forces and the geometry of the setup?
 
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