Solving for Fp: Bucket and Crank Problem with Unknown Forces

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To solve the bucket and crank problem, one must equate the moments applied to the pulley by the force F at crank length x and the weight of the mass M at diameter D. The force exerted by mass M includes both its weight and the force from acceleration, which needs to be calculated based on the distance L and time T. The key formulas involve torque and linear acceleration, requiring the determination of acceleration to find the necessary crank length x. Additionally, the maximum and minimum forces on the pulley axle can be derived once the first part is solved. Understanding these relationships is crucial for addressing both parts of the problem effectively.
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I have a problem of two parts which I don't know what formulas to use. I would be greatful if someone could help me with it:

A bucket with the mass M is hanging in a cord with the length of L which in turn goes over a pulley with a diameter of D. The pulley has a crank with the length x. The force which is used at the end of the crank is F. How long must x be to make it possible to pull the bucket all the way up, L, in T seconds?



_____
/ / Fp \ F
II 0= I========
I \___/
I D
L I
I
IIIIIIIII
I M I
IIIIIIIII


The second part of the problem is to identify the maximum and minimum force (Fp-max & Fp-min) on the stand (that is the axle in the middle of the pulley).

L,M,D,F,T are known and Fp-max and Fp-min are unknown.

What formulas should be used to solve this problem?

/Cheesy
 
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The moment applied to the pulley, which is equal to the force F applied to the crank arm of length 'x', must equal the moment applied by the mass M at diameter, D.

The force applied by the mass M is the sum of its weight and force developed by the acceleration.

One must determine that acceleration in terms of distance, L, and during of acceleration, T.

http://hyperphysics.phy-astr.gsu.edu/hbase/mot.html#c1
 
thanks a lot of help
 
the second question is easy when you know the first.
 
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