The coin has static and kinetic coefficients of friction with the turntable surface of static friction=0.70 and kinetic friction=0.50. The turntable very slowly speeds up to 60 rpm.
Does the coin slide off? Yes or no.
Does the coin slide off? Yes or no.
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A 0.005 kg coin is placed 0.15 m from the center of a turntable....?
The coin has static and kinetic coefficients of friction with the turntable surface of static friction=0.70 and kinetic friction=0.50. The turntable very slowly speeds up to 60 rpm.
Centripetal force = mass * velocity^2 ÷ radius
As the speed of the turntable increases, the centripetal force increases. For the coin to move, the friction force must be less than the centripetal force.
A 0.005 kg coin is placed 0.15 m from the center of a turntable, so r = 0.15 meter.
60 revolution per minute = 1 revolution per second
1 revolution/s= 1 circumference /s= 2 * π * r = 2 * π * 0.15 = (0.30 * π) m/s
Velocity of coin = (0.30 * π) m/s
Centripetal force = 0.005 * (0.30 * π)^2 ÷ 0.15 ≈ 0.0296 N
Friction force = µ * m * g
Static friction force = 0.7 * 0.005 * 9.8 = 0.0343 N
Kinetic friction force = 0.5 * 0.005 * 9.8 = 0.0245 N
The coin cannot “start” to slide, because the Static friction force is greater than the centripetal force. The coin is moving at the same speed as the turntable. If the coin was already sliding, it would continue, because the Kinetic friction force is less than the centripetal force.
Does the coin slide off? NO
The coin has static and kinetic coefficients of friction with the turntable surface of static friction=0.70 and kinetic friction=0.50. The turntable very slowly speeds up to 60 rpm.
Centripetal force = mass * velocity^2 ÷ radius
As the speed of the turntable increases, the centripetal force increases. For the coin to move, the friction force must be less than the centripetal force.
A 0.005 kg coin is placed 0.15 m from the center of a turntable, so r = 0.15 meter.
60 revolution per minute = 1 revolution per second
1 revolution/s= 1 circumference /s= 2 * π * r = 2 * π * 0.15 = (0.30 * π) m/s
Velocity of coin = (0.30 * π) m/s
Centripetal force = 0.005 * (0.30 * π)^2 ÷ 0.15 ≈ 0.0296 N
Friction force = µ * m * g
Static friction force = 0.7 * 0.005 * 9.8 = 0.0343 N
Kinetic friction force = 0.5 * 0.005 * 9.8 = 0.0245 N
The coin cannot “start” to slide, because the Static friction force is greater than the centripetal force. The coin is moving at the same speed as the turntable. If the coin was already sliding, it would continue, because the Kinetic friction force is less than the centripetal force.
Does the coin slide off? NO