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Home Concept Builders Vibrations and Waves Frequency and Period Help Help 9

Frequency and Period - Questions 9 Help

Vibrating objects undergo back-and-forth vibrations about a fixed location. Two physical quantities that describe these vibrations are frequency and period. While related, they have quite different definitions, meanings, and mathematics.

There are two similar versions of this question. Here is one of those versions:
 

Version 1:
Once tapped with a rubber hammer, the tines of a tuning fork begin vibrating. A computer-interfaced microphone detects the resulting vibrations of the surrounding air, providing the plot of pressure as a function of time. Consider the two cases below. In which case does the tuning fork have the greatest frequency?
 

The frequency of a vibrating object refers to how often the object undergoes a complete back and forth cycle about its customary resting position. To calculate such a quantity, one would need to count the number of complete vibrational cycles in a given amount of time and divide the number of cycles by the amount of time. As such, the unit of frequency is cycles per second. This is sometimes equated with the unit Hertz and abbreviated as Hz.

The plot shows time plotted along the horizontal axis. And the familiar sinusoidal, up-and-down repeating changes are shown. You can start at a high point on the sinusoidal curve and trace along the curve to the next highest point. This is referred to as a cycle. The most frequent case is the one that completes the greatest number of these cycles in the given amount of time.

Try this link to The Physics Classroom Tutorial for more help with the concepts of frequency and period:

Frequency and Period

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