8. Centripetal Forces & Gravitation

An AC waveform completes $30$ cycles in $\frac{1}{2}$ second. What is its frequency in hertz?

In the context of uniform circular motion, what is the physical quantity that represents the number of cycles per second that the pressure changes repeat?

What is the period of a signal that has a frequency of $60\mathrm{Hz}$?

Which unit is used to measure frequency as cycles per second in uniform circular motion?

In the context of uniform circular motion, what is the SI unit for $f$ (frequency)?

In uniform circular motion, how long does it take for an object, such as a flag, to complete one full rotation around the circle?

In uniform circular motion, how are the period $T$ and frequency $f$ of the motion related?

In uniform circular motion, how does the period $T$ change as the orbital radius $r$ increases, assuming the speed remains constant?

In uniform circular motion, what is the mathematical relationship between the period $T$ and the frequency $f$?

If the period of an object in uniform circular motion were doubled, what would happen to its frequency? ($f=\frac{1}{T}$)

For an alternating current with a frequency of $60\mathrm{Hz}$, what is the period of the oscillation?

In the context of uniform circular motion, about how long does it take for Earth to complete a full rotation on its axis (i.e., what is the period $T$ of Earth's rotation)?

At its Ames Research Center, NASA uses its large '20-G' centrifuge to test the effects of very large accelerations ('hypergravity') on test pilots and astronauts. In this device, an arm 8.84 m long rotates about one end in a horizontal plane, and an astronaut is strapped in at the other end. Suppose that he is aligned along the centrifuge's arm with his head at the outermost end. The maximum sustained acceleration to which humans are subjected in this device is typically 12.5g. How fast in rpm (rev/min) is the arm turning to produce the maximum sustained acceleration?