# How to calculate the period of a wave

**Many scientific disciplines incorporate the concepts of wave frequencies and periods**. Physicists, engineers and astronomers, study and work with the energy of the waves. Examples of wave energy are light waves of a distant galaxy, radio waves received by a cell phone and the sound waves of an orchestra. Regardless of the source of the wave, the relationship between waveform frequency and the period is the same. A **wave period** is the time in seconds between two wave peaks and is inversely proportional to frequency.

**If you want to know the period of a wave**, start by counting the number of times the wave reaches its peak in a certain period of time. Use an oscilloscope to see the shape of the wave.

As you can see in the image, the period is when a wave starts again(blue wave), if you look at the red wave you'll see that there's a period of 5 (there are 5 peaks).

Now, divide the number of waves by the amount of time in seconds. This number will give us the frequency of the **wave**. For example, suppose that 21 waves are produced in 3 seconds. Its frequency equals 21 divided by 3, which is 7 Hz. Frequency units are Hertz.

Another example:

- The image in the top square has a total of 5 waves in 5 seconds, so the frequency is equivalent to 5 divided by 5, which equals 1 Hertz.
- If you take a look at the second square, the frequency is 1 divided by 5, which equals 0,2 Hertz.

Calculate the opposite of the frequency to get the **period of the wave**. For example, one divided by 7 Hertz equals a period of approximately 0.14 seconds.

In the example images:

- The period in the top image is 1 divided by 1 Hz, which is 1 second.
- The period of the bottom image is 1 divided by 0,33 Hz, which is 3 seconds.

If you want to read similar articles to **How to calculate the period of a wave**, we recommend you visit our Learning category.