## Introduction: Magnet Trampoline

While sometimes a bit polarizing, magnets enjoy a good party, too.

Whether you're feeling repulsive or like sticking together, the magnet trampoline is a very simple introductory project to teach some of the basics of forces and magnetism. Slap it together, take a bounce, and see what variations you can come up with!

• What: Magnet Trampoline
• Where: both the north and south poles, really
• Concepts: magnetism, forces, gravity, potential energy, springs
• Time: ~ 5 minutes to make
• Cost: ~\$0.75-\$1.25 (and re-usable)
• Materials:
• Ceramic Disc Magnets (donut-shaped, like these ones)
• Wood Dowel (match size of magnet donut hole)
• Wood block (piece of 2x4 works great)
• Tools:
• Drill

Let's bounce!

## Step 1: Choose and Cut a Dowel

Let's make a stick!

First up is to find a dowel that works with your magnets. Check the diameter for one where the magnets can slide easily but is otherwise fairly snug. Cut a length of about 8-12".

## Step 2: Drill and Place Your Dowel

You know the drill!

Find a drill bit that is the same size as your dowel and drill a hole halfway into a block of wood, keeping the drill positioned as vertically up and down as you can (a drill press works great if you have one). Twist to fit the dowel snugly in.

You are so so close.

## Step 3: Tower Time!

Place your magnets on your dowel reversing the orientation of the poles each time. This can be with anywhere between 3 and 12 magnets (or more, too). You want each of them to repel one another and to stay suspended in a springlike state. Check out the interesting variation in spacing between, and give push them down to have them spring back!

## Step 4: Noticing and Going Further

The joy in this project is its initial simplicity, but there is much more to do and notice. I am always amazed at what students come up with for exploration questions, but some prompts can include:

• What happens when you have some magnets that attract? What happens when you add magnets to the chain?
• What happens if you move that stack of magnets to the middle? Or the bottom?
• What is the distance between the lowest and the second lowest magnet? What about the second highest and the highest? Can you graph the distances between them all?
• Try drilling into the block of wood at different angles? What is the spacing like between those magnets? Are they farther apart or closer together than your vertical one? Why do you think that is?
• Why does a magnet spring up when you hold it down? Can you make it shoot higher?

Let me know your variations in the comments below. Enjoy, repel, stick together, and as always, keep exploring.