How Do You Calculate Tension in a Pulley System with Friction?

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AI Thread Summary
To calculate the tension in a pulley system with friction, the problem involves two blocks with masses of 50.0 kg and 100 kg connected by a string over a frictionless pulley. The coefficient of kinetic friction for the 50.0 kg block on an incline is 0.250. The tension in the string can be determined by analyzing the forces acting on each block, particularly considering the net force and gravitational components. The participant initially struggled with setting up the equations correctly but eventually resolved the confusion regarding the relationship between tension and weight. Understanding the forces and energy changes in the system is crucial for accurate calculations.
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Homework Statement



Two blocks of mass m1=50.0 kg and m2=100 kg are connected by a string of negligible mass. The pulley is frictionless and also of negligible mass. The coefficient of kinetic friction between the 50.0 kg block and the incline is 0.250.

a) Determine the tension in the string.
b) Find the acceleration of the system.
c) Determine the decrease in total mechanical energy of the system (due to the presence of the frictional force) when the 50.0 kg block moves from point A to point B, a distance of 20.0 m.

Homework Equations



T=??

The Attempt at a Solution



I am fairly certain that I'll only need help with part a. I have a really hard time figuring out what to set tension equal to (and why). I had T-mg=F for the 100 kg block, but figured I couldn't do much with that. Instead I tried with the second block to use T=mg+fgsin37 but the answer I get is somewhere in the 3000s while my study guide says I should be getting 589 N. How do I go about setting up tension for this problem?
 

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try setting up the blocks into vectors first, this may help you be able to realize what you can set equal to one another
 
then u should consider Fnet=W-T after you determine your vectors
 
I'm not quite sure what you mean by Fnet=W-T

I don't see how work comes into this system, since it seems to me that I don't have any 'initial' conditions from which to determine energy.
 
Last edited:
NVM got it. Thanks!
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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