Magnetic Levitation

Magnetic Levitation

Can you make a pencil suspend in air by just using magnets and with no other support ? A method where an object is suspended in air with no support other than magnetic fields is called Magnetic Levitation. The magnetic force is used to counteract the gravitational pull. The Shanghai Maglev Trains are based on the very concept of magnetic levitation.

Advertisements

So, let’s learn the science of magnetic force in this interesting experiment.

What you need

  • Ring Magnets ( we bought online from here )
  • Foam Board or a cardboard box
  • Strong Plastic card ( like your office old batch id card ) as a stopper
  • Pencil or Dowel ( that will fit securely in ring magnets )

Disclosure : Some of the links below are affiliate links, meaning, at no additional cost to you, I will earn a commission if you click through and make a purchase.

First, cut a large rectangular piece from the foam board. Make 3 cuts 5cm wide in the foam board parallel to each other from a distance at 2cm, 6.5cm and 12.5 cm from one end of the board. Then, put the stopper in the first slit at 2 cm.

Fit two ring magnets onto the pencil or dowel, at a distance from each other, the polarities of these magnets do not matter. I used a rubber band on the pencil to keep the magnets in place, as shown in the picture.

Now, insert two ring magnets apart from each other in the middle slit next to the stopper. These magnets should attract to the front magnets on the dowel or pencil (at the writing end ).

Force of attraction

Insert the remaining two ring magnets in the last slit. These magnets should repel the back magnets on the dowel or pencil.

Force of repulsion

That is how the final assembly would look like.

Placement of magnets

Now place the pencil between the four magnets with its tip resting on the stopper and it should levitate in the air. You might have to adjust the magnets on the pencil so that it levitate perfectly in the air.

Magnetic levitation in action
The pencil is suspended in air
proof checking

Isn’t it AMAZING to see the pencil levitate ! That made my kids wonder if superman also has the power of Magnets ! What do you think ?

How it works

There are multiple forces working on the pencil. There is a magnetic force of attraction from the front magnets. And a magnetic force of repulsion from the back magnets. The stopper is providing a force of reaction against the forward movement  in order to keep the pencil stable and not let it move forward. That way, the forces are all perfectly balanced in the horizontal direction. Similarly, in the vertical direction, there is a gravitational force and the front magnets provide a downward force and the back magnets provide an upward force. The interplay of all these different kind of forces keep the pencil stable and levitating in air without support.

The final assembly

Don’t have time to buy all the materials, then this kit is a good tool to teach and do tons of experiment with magnets.

And while you are here, I hope these science experiments might interest you.

Please, consider liking my facebook page and share this blog . Thank you for all your support.

Leave a Reply

Your email address will not be published. Required fields are marked *