# FBD for Circular Motion

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Hi,

I'm having a really hard time understanding this question. I am not looking for someone to show how it's done, but just help with me drawing free body diagram because it is really driving me crazy (I've spent at least 2 hours just to do that and go nowhere). Thank you!

Problem: An elevator cable winds on a drum of radius 90.0 cm that is connected to a motor. (a) If the elevator is moving down at 0.50 m/s, what is the angular speed of the drum? (b) If the elevator moves down 6.0 m, how many revolutions has the drum made?

My issue is that I don't understand what this "drum" is for elevator. I've never heard of it before.

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Hi,

I'm having a really hard time understanding this question. I am not looking for someone to show how it's done, but just help with me drawing free body diagram because it is really driving me crazy (I've spent at least 2 hours just to do that and go nowhere). Thank you!

Problem: An elevator cable winds on a drum of radius 90.0 cm that is connected to a motor. (a) If the elevator is moving down at 0.50 m/s, what is the angular speed of the drum? (b) If the elevator moves down 6.0 m, how many revolutions has the drum made?

My issue is that I don't understand what this "drum" is for elevator. I've never heard of it before.

I'm assuming they're thinking of it as a sort of winch. Draw a picture based on that idea and you should be able to solve the problem simply enough with some basic reasoning.

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Actually, you just made me to understand the problem! I like the word "winch" better than the "drum." Thanks so much! :D:D:D

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