Question

a standard turntable has a radius of 15 cm and spins at 33 rpm 1. What is the turntable's frequency? period? angular frequency? Linear (tangential) speed of a point on the edge of the turntable Suppose that a .10gram coin rests near the edge of the turntable as the turntable spins 1. Find the magnitude of the acceleration of the coin. 2. Fine the magnitude of the net force acting on the coin. Which force(s) are primarily responsible for creating this net force?

Answer #1

**1)**

**frequency f = w/(2pi)**

**w (omega) = angular frequency = 33 rpm = 33*2pi/60
rad/s**

**frequency = (33*2pi/60)/(2pi) = 33/60 = 0.55
Hz**

**time period T = 1/f = 1.82 s**

**angular frequency w = 33*2pi/60 rad/s = 3.46
rad/s**

**linear speed v = r*w = 0.15*3.46 = 0.519 m/s**

**======================================**

**1)**

**magnitude of acceleration a = r*w^2 = 0.15*3.46^2 = 1.79
m/s^2**

**2)**

**magnitude of the net force acting on the coin = m*a =
10*10^-3*1.79 = 0.0179 N**

**centripetal force**

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