This kit contains the materials and instructions for 3 activities. inspired by research at the University of Wisconsin- Madison.
You will find the following materials in your kit:
- 1 Pencil
- 1 Piece of sticky tack
- 1 Refrigerator magnet
- 2 Bar magnets
- 4 Ring magnets
- 6 Washers
- 1 Square of visualizer film
How do Magnets Work?
Magnets are materials that attract and repel similar materials that also have magnetic forces. These magnetic forces are produced when the electrons, which have tiny magnetic fields, all line up in the same direction and produce an overall electric field in the material.
Permanent magnets are made of certain materials such as iron or nickel where the electron alignment orientation is permanent; these are also called ‘ferromagnets’. In these magnets, the magnetic field goes from the north pole to the south pole. The Earth is one big magnet with a north and a south pole; compasses and navigation equipment use Earth’s magnetic field for orientation. Magnets are all around us, not just on our refrigerator – electronics use magnets to store information, roller coasters, clocks and some medical devices all use magnets!
- Find the two bar magnets that have an S (south) and N (north) on them.
- Touch the two N sides together – what do you feel? This is called repulsion.
- Now touch the N and S together – what do you feel? This is called attraction.
Some Magnets are Stronger than Others
There are several different types of magnets in your kit. See how many of the metal washers (disks with holes in the center) you can pick up with each magnet. Which magnet picked up the most (strongest)? Which magnet is the weakest?
Try using one washer to pick up another washer. Now pick up one washer with the strongest magnet you have. Can the washer attached to the magnet pick up a second washer? A third? Can you make a chain? Some metals (like the steel washers) can be made into magnets when they are touching something that is a permanent magnet.
Where are Magnets Used?
- Electronics use magnets to store information
- Vending machines use magnets to see if money is real
- Hospitals use big magnets in machines called MRIs to see inside you
- High speed trains use strong electromagnets to float slightly over the track so it can move faster – up to 200 mph!
- The Earth is one big magnet with a north and a south pole; compasses and navigation equipment use Earth’s magnetic field
Fun Facts About Magnets
- Birds follow the Earth’s magnetic fields to migrate
- Neodymium (very strong) magnets are suspected to repel sharks – sharks can sense electrical fields, which magnets can distort
- If you cut a magnet in half, you will get two identical magnets both with a north and south pole
- If you crush a magnet, it stops working because the molecules will lose their alignment
This is an accordion element with a series of buttons that open and close related content panels.
Not suitable for children under 5. Magnets are choking hazards for small children and strong magnets can pinch skin and fingers.
Scanning Probe Microscopy- Refrigerator Magnet
- Remove the labeled “probe strip” from your refrigerator magnet by bending it back and forth and then tearing it along the perforation.
- Gently drag the dark side of the probe strip along the dark, unprinted side of the magnet in both directions, shown below.
You can “feel” the magnetic field – and it will feel different based upon the direction the probe strip goes. Based on what you feel, which of these three diagrams best represents how the magnetic field of this fridge magnet is arranged? (see magnetic viewing film section for answer)
The way you just felt the magnet field is very similar to an instrument scientist use call scanning probe microscopes.
These instruments use a probe tip so small that, when dragged across a surface, it can “feel” bumps from individual atoms! Just like you could “feel” the difference in the magnetic field.
Magnetic Field Viewing Film
You can see magnetic fields by using the magnetic field viewing film in your kit (it’s the thin, green sheet). This film contains nickel flakes. These flakes can appear shiny when a magnetic field is parallel to the sheet and dark when the magnetic field is through the sheet.
Look at the different magnets with the film, the areas that appear dark on the magnet represent the poles.
How does the shape of the magnet affect the shape of the magnetic field? For the ring magnet, look at the magnet through the film on its side to see how each side of the magnet is a separate pole.
For the ring magnet, look at the magnet through the film on its side to see how each side of the magnet is a separate pole.
Levitation isn’t just a magic trick, it can also be achieved using magnetism! Learn how, and why, we can make magnets float in the following activity.
- find the ring magnets, pencil, and sticky tack in your kit.
- Attach one ring magnet at the bottom of the pencil with the sticky tack.
- Drop another magnet onto the pencil, what happens? Does it float or stick together? Now flip that magnet over and see what changes. Now try to stack all of the magnets in an orientation where they all float.
How it works:
When two of the same poles face each other, such as north-north or south-south, the repulsive force from magnets is strong enough to cause the magnet to float.
The repulsive force from magnets can be used on a much bigger scale to levitate larger objects such as high-speed trains off the track so they can move really fast (up to 200 mph!) without getting hot.
Two British scientists were able to levitate a living frog because of molecular magnetism using similar technology!
Click here to watch the full video!