Chapter 23 Waves - Section 1

Every 5 seconds, a pendulum completes one cycle. What are the period and frequency of this pendulum?

• 5 Hz and 2 seconds

• 5 seconds and 0.2 Hz

The period of an oscillator is 1 minute. What is the frequency of this oscillator in hertz (Hz)?

• 0.2 Hz

• 0.02Hz

• 2 Hz

How often would you push someone on a swing to create a frequency of 0.4 hertz?

• You would need to push once every .25 seconds.

• You would need to push once

  every 25 seconds.

• You would need to push once every 2.5 seconds.

The picture shows the parts of a pendulum clock. The minute hand moves 1/60 of a turn after 30 cycles. What is the period and frequency of this pendulum?

• There are 30 cycles/second so the frequency is 30 Hz. The

  period is 0.03 second.

• There are 30 cycles/second so the frequency is 0.03 Hz. The

  period is 30 seconds.

• There are 30 cycles/second so the frequency is 60 Hz. The

  period is 0.03 second.

A Ferris wheel spins 5 times in 10 minutes. Calculate the period and frequency of the Ferris wheel.

• The frequency is 120 Hz. The period is 0.008 seconds.

• The frequency is 0.008 Hz. The period is 120 seconds or

  2 minutes.

Which is the best example of a cycle: a turn of a wheel or a slide down a ski slope?

• a turn of a wheel

• a slide down a ski slope

Every 10 seconds a pendulum completes 2 cycles. What are the period and frequency of this pendulum?

• The period is 5 seconds/cycle and the frequency is 0.2 Hz

• The period is 0.2 seconds/cycle and the frequency is 5 Hz

A graph of the motion of a pendulum shows that it swings from +5 centimeters to –5 centimeters for each cycle. What is the amplitude of the pendulum?

• 2.5 cm

• 5 cm

• 10 cm

What is the period of the oscillation shown in the diagram above?

• 2 seconds.

• 4 seconds.

• 20 seconds.

Resonance happens when:

• a periodic force is applied at the natural frequency.

• an oscillator has more than one natural frequency.

• a force is periodic and not constant.

• the amplitude of an oscillator grows large over time.