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The rotor (flywheel) of a toy gyroscope has a mass of 0.140 kg. Its moment of inertia about its axis is 1.20 × 10−4 kg·m2. The mass of the frame is 0.0250 kg. The gyroscope is supported on a single pivot (see Figure 10.67) with its center of mass a horizontal distance of 4.00 cm from the pivot. The gyroscope is precessing in a horizontal plane at the rate of 1 revolution in 2.20 s. (a) Find the upward force exerted by the pivot. (b) Find the angular speed with which the rotor is spinning about its axis, expressed in rev/min. (c) Copy the diagram and draw vectors to show the
Figure 10.67
Problem 50.
10.50. Set Up: The precession
Solve: (a) Fp = wtot = (0.165 kg)(9.80 m/s2) = 1.62 N
(b)
(c) If the figure in the problem is viewed from above,
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