"Understand Motion of Block on Turntable

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AI Thread Summary
A block on a frictionless turntable will move outward due to centrifugal force, eventually sliding off the edge as it cannot maintain circular motion without friction. In the case of a turntable with static friction, the block will begin to slip when the centripetal force required for circular motion exceeds the maximum static friction force. To find the coefficient of static friction (Us) in terms of angular velocity (W), radius (R), and gravitational acceleration (g), one must equate the forces involved. The discussion highlights confusion over the initial motion of the block and the need for relevant equations to solve the problem. Understanding these concepts is crucial for accurately addressing both parts of the homework question.
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Turntable ??

Homework Statement


A block of mass M is place a Distance R from the center of a turntable rotating at W radians/sec.
A. If the turntable is a frictionless surface, explain the motion of the block.
B. If the turntable has coefficient of static Friction Us and the block is ready to begin slipping when the turntable is rotating with W radians/sec, find an expression for Us in terms W, R, and g.


Homework Equations





The Attempt at a Solution


What is it talking about explain the motion of block? and I don't even know where to begin with the second part because I don't understand the first. I know the block will begin to slide and eventually fall off the turntable. But I'm not sure what its asking for.
 
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For part A, when it asks you to explain the motion of the block, id think that it wants you to describe how the block moves (does it go around with the table? Does it move off in some other direction?) and explain why this motion happens.
 


It would move closer and closer to the edge of the turntable with each rotation. I understand that, however, I know that's not going to be the right answer unfortunately.
 


student 1 said:
It would move closer and closer to the edge of the turntable with each rotation. I understand that, however, I know that's not going to be the right answer unfortunately.
For part (A), what force makes the block move?

You haven't done anything yet for part B. In particular, what are the relevant equations? We put those things in the template so you would use them.
 
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