A pendulum is made by tying a 75 g ball to a 130-cm-long string. The ball is pulled 5.0° to the side and released. How many times does the ball pass through the lowest point of its arc in 7.5 s?

(II) What is the period of a simple pendulum 47 cm long

(b) when it is in a freely falling elevator?

A simple pendulum oscillates with frequency ƒ What is its frequency if the entire pendulum accelerates at 0.35 g

(b) downward?

(II) The balance wheel of a mechanical (analog) watch is a thin ring of radius 0.95 cm attached to a coil spring (roughly like Fig. 14–35). It oscillates with a frequency of 1.55 Hz. If a torque of 1.1 x 10⁻⁵ m • N causes the wheel to rotate 45°, calculate the mass of the balance wheel.

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