What is Solenoid? - Definition, Uses & Examples

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: What is a Compound Machine? - Definition & Examples

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:00 What is a Solenoid?
  • 0:30 How Do Electromagnet…
  • 1:20 Uses of Electromagnet…
  • 2:45 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: David Wood

David has taught Honors Physics, AP Physics, IB Physics and general science courses. He has a Masters in Education, and a Bachelors in Physics.

In this lesson, you will learn what a solenoid is, how it relates to electromagnets, and how it is used in a few real-life situations. A short quiz will follow.

What is a Solenoid?

Solenoids and electromagnets technically are not the same thing, but people talk as if they are. A solenoid is just a coil of wire, but when you run a current through it, you create an electromagnet. Since this is by far the most useful application of a coil of wire, it's not surprising that when you say the word 'solenoid,' people tend to assume you mean electromagnet. Electromagnets are particularly useful because, unlike regular magnets, they can be switched on and off, and strengthened by increasing the current flowing through them.

How Do Electromagnet Solenoids Work?

When a lazy charge sits on its couch, doing nothing, it is surrounded by an electric field. This makes sense, because it's an electric charge, after all. But once that charge gets some motivation and goes for a run around the block, suddenly it produces a magnetic field. This might strike you as odd, and you wouldn't be alone! As physicists figured out later, both fields are part of the same force of nature: electromagnetism.

Because of this, we can create a magnet by simply running a current through a wire. When we run a current through a solenoid, however, we get a super strong magnet because the magnetic field is concentrated inside the coil. This can be incredibly useful in our everyday lives.

Uses of Electromagnet Solenoids

Electromagnetic solenoids find uses all over the world. They're in hotel door locks, water-pressure valves in air conditioning systems, MRI machines, hard disk drives, speakers, microphones, power plants, and cars. You can hardly swing a bat without hitting a solenoid.

Speakers and microphones, for example, both contain solenoids. In fact, a speaker and microphone are pretty much exactly the same thing in reverse of each other. A speaker takes electrical signals and runs it through a solenoid to create motion; that motion drives the speaker and creates a sound. A microphone does the opposite; your voice pushes the solenoid back and forth, and that motion of the solenoid creates an electrical signal that can be used to create the sound elsewhere. Without solenoids, we wouldn't be able to record or reproduce sound at all.

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

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 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.

To learn more, visit our Earning Credit Page

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 risk-free for 30 days!
Create an account