Force in a dynamics of rotation problem?

AI Thread Summary
The discussion revolves around calculating the force exerted on a windlass cylinder by the axle while a bucket of water falls. The cylinder has a mass of 12.4 kg and is affected by its weight and the tension from the falling bucket. Initially, there was confusion regarding the interpretation of the question, particularly whether it was asking for the normal force. The correct approach involves summing the weight of the cylinder and the tension in the rope to find the total force acting on it. Ultimately, the problem clarifies that both forces must be considered to arrive at the solution.
erik-the-red
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A bucket of water of mass 15.0 kg is suspended by a rope wrapped around a windlass, that is a solid cylinder with diameter 0.290 m with mass 12.4 kg. The cylinder pivots on a frictionless axle through its center. The bucket is released from rest at the top of a well and falls a distance 11.0 m to the water. You can ignore the weight of the rope.

The fourth and final part of the question is "While the bucket is falling, what is the force exerted on the cylinder by the axle?"

Quite frankly, I don't really understand this question. When I drew the free body diagram, I'm inclined to say the answer is (12.4)(9.80).

Is this asking for the normal force?
 
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Never mind, I got it.

I forgot that it's just (12.4)(9.80) + T, where T is 43.0 and was asked for in the first part of the question.
 
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I had trouble with the question intially also, because of the wording, but it makes sense: there are two forces that act on the cylinder while the bucket is falling, its own weight, and the Tension of the bucket.

By adding these, you get the total force that's acting on the cylinder.

-L.
 
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