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A coin is placed 29.99 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 32.95 rpm (revolutions per minute) is reached, at which point the coin slides off. What is the coefficient of static friction between the coin and the turntable?

User Aarti
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Final answer:

To determine the coefficient of static friction between the coin and the turntable, analyze the forces acting on the coin at the point it begins to slide off. Use the centripetal force and linear velocity formulas to calculate the coefficient of static friction.

Step-by-step explanation:

The coefficient of static friction can be determined by analyzing the forces acting on the coin when it starts to slide off the turntable. At this point, the centripetal force acting on the coin is equal to the force of static friction. The centripetal force can be calculated using the formula: Fc = m * (v^2 / r), where m is the mass of the coin, v is the linear velocity, and r is the radius.

Since the coin remains fixed on the turntable until a rate of 32.95 rpm is reached, we can convert this to linear velocity using the formula: v = (2 * π * r * n) / 60, where n is the rotational speed in rpm.

Once we have the linear velocity, we can substitute it into the centripetal force formula along with the mass of the coin and the radius of the turntable to solve for the coefficient of static friction.

User Joshua McKinnon
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