Finding Force Needed to Climb Wall: Friction Coefficient u & Angle @α

AI Thread Summary
To determine the minimum force required for a man to climb a wall while pushing against both walls at an angle, it is essential to analyze the forces at play, including friction. The friction involved is static, as it prevents the man from sliding down while he exerts force against the walls. The direction of the friction force must oppose the potential sliding motion, acting upwards in this scenario. A proper free-body diagram can help visualize the forces, including the applied force at angle alpha and the resulting static friction. Understanding these dynamics is crucial for solving the problem effectively.
paras02
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Homework Statement


A man standing in the corner of the wall tries to climb up
by pushing against both the walls, if the friction coefficient between the wall and his elbow is 'u' , then find the minimum force from which the man must push against in order to climb up the wall, given that he is pushing the wall at an angle @ ( alpha )?



Pls help me with the direction in which friction and all other forces are acting...
 
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What kind of friction is involved here: static or kinetic?
 
I think it's fair to assume static or at least static = kinetic, else the man has a serious problem.
 
So friction always acts along a surface - so sketch one of the surfaces and put an arrow on it indicating which way the man is pressing (at an angle remember). Which way does the static friction have to act to stop the man from sliding?
 
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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