# Physics a level question

#1
A small body of mass m rests on a horizontal turntable at a distance r from the centre.
If the maximum frictional force between the body and the turntable is –––, what is the
angular speed at which the body starts to slip?
I dont understand how the answer is sqrt(9/2r)
0
1 month ago
#2
A small body of mass m rests on a horizontal turntable at a distance r from the centre.
If the maximum frictional force between the body and the turntable is –––, what is the
angular speed at which the body starts to slip?
I dont understand how the answer is sqrt(9/2r)
Without knowing what the maximal frictional force actually is, we can't check the answer. But the idea is to think about what is providing the centripetal force when the body is moving in a circle and use that to work out the angular speed when this centripetal force has got as large as it is allowed to. If it moves with a greater angular speed than that, it won't stay in place and move in a circle any more.
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