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Period and Frequency of a Pendulum - help9

Not every pendulum is the same. Some have long strings and others short strings. Some have a massive pendulum bob and others have a light-weight pendulum bob. And some are pulled back to a large angle and released and others are released from a small angle. But how do these variables affect the period and the frequency of a pendulum? That's the basic idea of this activity. Learn more about it in the How to Think About This Situation section.

There are four similar versions of this question. Here is one of the versions:

Version 1:
Anna Litical is studying the effect of string length (L), bob mass (m), and swing angle (θ) upon the frequency of a pendulum's vibrations. The parameter values used for three trials are shown. Rank the three trials in order of their frequency (f).


The Relationship
Perhaps you have done the experiment. It certainly is more exciting to discover the relationship on your own than to be told what it is. And if you have done the experiment, then you know that the one variable that affects the period of a pendulum is the length of the string that the pendulum bob is tied to. A longer string results in a longer period and a smaller frequency. That is, a bob on a long string will take a longer time to vibrate back and forth; the frequency at which it does its vibrations is not as frequent as a short string pendulum. The mass of the bob has little observable influence upon the period. The same is true of the angle from which the bob is released.


Analyze It
Given the above relationship, your task is to analyze the provided data. Give attention to the length of the pendulum. Longer strings have longer periods and lower frequencies. With a focus on the length, make your rankings of the three trials. You got this!

Try this link to The Physics Classroom Tutorial for more help with the concept of pendulum motion:

Pendulum Motion