Mass on a rotating turntable problem.

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The discussion revolves around analyzing the forces acting on a mass placed on a rotating turntable. It highlights that the normal force equals the weight of the block in the vertical direction, while static friction acts to the left in the horizontal direction. A centripetal force is necessary for circular motion, which is provided by friction, leading to the equation Fc = Ff. The relationship between the speed of the turntable and the block is established as omega*R, where omega is the angular velocity and R is the radius. The conversation concludes with a suggestion to calculate the time required for the block to reach the necessary speed.
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[PLAIN]http://img841.imageshack.us/img841/7913/314pw.jpg

I'm having a bit of trouble with this one.

So the FBD of the block.

In the y coordinates, the normal equals its weight

in the x coordinates, we have static friction to the left, and is there a force to the right? There as to be right, since it eventually begins translating radially?

Just looking for a little guidance, thanks!
 
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From the point of view of the outside observer, a centripetal force is required to hold the mass in circular motion. This is provided by the force of friction. So you begin with Fc = Ff, put in the details and calculate the speed for which they are just equal.
 
the speed of the turntable and the block or just equal?

omega*R?
 
Yes, the speed of the turntable omega*R.
Then you can go for the time to reach that speed.
 

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