Question

In: Physics

A coin is placed 18.0 cm from the axis of a rotating turntable of variable speed....

A coin is placed 18.0 cm from the axis of a rotating turntable of variable speed. When the speed of the turntable is slowly increased, the coin remains fixed on the turntable until a rate of 35.0 rp (revolutions per minute) is reached, at which point the coin slides off.

Part A- What is the coefficient of static friction between the coin and the turntable? Express your answer using three significant figures.

Expert Solution

Gravitational acceleration = g = 9.81 m/s2

Mass of the coin = m

Distance the coin is placed from the axis = R = 18 cm = 0.18 m

Angular speed of the turbtable = = 35 rpm = 35 x (2/60) rad/s = 3.665 rad/s

Normal force on the coin from the turntable = N

N = mg

Coefficient of static friction between the coin and the turntable =

Friction force on the coin = f

The centripetal force for the circular motion of the coin on the turntable is provided by the static friction force on the coin.

= 0.246

A) Coefficient of static friction between the coin and the turntable = 0.246

genius_generous answered 2 years ago

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