Video: Frequency vs. Period

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Frequency vs. Period

 
Waves are repeated and periodic disturbances in a medium that cause particles to vibrate back-and-forth about a fixed position. Two quantities – frequency and period – describe the vibrational motion of these particles
 
Frequency refers to how often a particle completes a back-and-forth vibrational cycle. Frequency is not to be confused with speed. Speed refers to how fast a crest is moving – a distance traveled per time, with units of m/s. Frequency refers to the number of vibrations or cycles per time and is calculated by dividing the number of cycles by the time. Its units are cycles per second, also known as Hertz (Hz)
 
Period refers to how much time it takes a particle to complete one full vibrational cycle. It is the time per cycle and is calculated by dividing the time by the number of cycles. It has units of time – seconds, minutes, hours.
 
When comparing equations for frequency and period, you notice that one is the inverse of the other. Frequency and period are reciprocals of one another. So if you know frequency, you can calculate period … and vice versa. And the larger the frequency, the smaller the period … and vice versa.
 
These two graphs portray the position of a vibrating particle as a function of time. The graph on the left shows a greater number of cycles during the same amount of time. It has the greater frequency and the smaller period.
 
To calculate frequency and period, look for information about the number of cycles of vibration during the corresponding amount of time. Take the numbers and put them in the right place. Your calculator will help you determine the answer. And of course, don’t forget the unit!
 
I'm Mr. H, letting you know … You got this!
 


 
 

 

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