# How to Calculate Wavelength

Instructor: Thomas Zesiger

Thomas has taught electronics and communications engineering, math, and physics and has a master's degree in electrical engineering.

Discover practical examples of waves and the significance of wavelength. Learn the relationship of wavelength, frequency, and wave speed and how to calculate wavelength based on these parameters.

## Explanation of Wavelength

Ripples in water, sound traveling in air, and coordinated vibrations of objects are examples of waves you have probably encountered in your life. A good way to visualize a wave is to insert the end of a pencil into a container of still water. The surface of the water is disturbed, producing ripples, or waves.

Electromagnetic waves are special waves such as light, radio waves, microwaves, and x-rays that do not require a medium for propagation. We cannot see or hear these waves, but they exist in nature and in many of the products we use every day.

Regardless of the kind, every wave has a wavelength. Wavelength is the distance between two successive like points on a wave. Some examples are the distance between two adjacent peaks or two adjacent valleys. A peak is the highest point of a wave and a valley is the lowest point. Stated another way, wavelength is the time required to complete one full cycle of the wave.

Wavelength depends on two other important parameters: wave speed and frequency. The wave speed is the rate at which the wave moves through the medium of propagation and it is dependent upon the medium of propagation. For example, the water ripples previously mentioned travel through the water. Electromagnetic waves usually travel through the air, as do sound waves. Vibrations on a piano string travel through the string. The wave speed is different for all of these because the medium in which the wave propagates is different.

The frequency is the number of wave cycles passing a point per unit time. Stated another way, it is the number of oscillations per second in the wave. A higher frequency means a shorter wavelength and a shorter wavelength means a higher frequency. This leads us to the relationship between wave speed, frequency, and wavelength.

## How to Calculate Wavelength

Stated in words, the speed of the wave equals the number of cycles passing a point each second multiplied by the cycle length.

Mathematically stated: wave speed = cycles per second x cycle length

Wave speed, frequency (cycles per second), and wavelength (cycle length) are usually represented with the variables v, f, and the Greek letter lambda respectively. Solving for lambda, the equation becomes lambda = v/f.

Wave speed has units of distance per unit time. For example, meters per second or m/s. Frequency has units of Hz. Wavelength is measured in units of distance, usually meters (m).

To unlock this lesson you must be a Study.com Member.

### Register for a free trial

Are you a student or a teacher?
Back

Back

### Earning College Credit

Did you know… We have over 79 college courses that prepare you to earn credit by exam that is accepted by over 2,000 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

### Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it free for 5 days!

#### Explore our library of over 30,000 lessons

Click "next lesson" whenever you finish a lesson and quiz.
You now have full access to our lessons and courses. Watch the lesson now or keep exploring.
You're 25% of the way through this course! Keep going at this rate,and you'll be done before you know it.
Support