Did you know you can make a compass out of a needle? It’s a simple experiment and a great way to introduce the concepts of magnetism, magnetic poles, and the Earth’s magnetic field.
Print out detailed instructions and a supplies list below and preview the experiment with our demonstration video. We’ve included everything you need to get started and include a scientific explanation of “why it works” to help your scientists explore the concepts in more detail.
Floating Needle Compass Science Experiment Video
- Sewing Needle
- Sturdy Paper (enough to cut out a circle two inches in diameter)
- Shallow Dish
- Compass (optional, but it’s good to have for comparison)
Step 1 – Use scissors to cut a circle out of the piece of paper. The circle should be approximately 2 inches in diameter.
Step 2 – Tape a sewing needle in the middle of the circle.
Step 3 – Fill a shallow dish with water.
Step 4 – Use a magnet and rub it along the needle in the same direction about 20 times.
Step 5 – Slowly place the piece of paper into the water. It will float along the top.
Step 6 – Watch as the circle begins to spin around until the needle is pointing in the direction of north, just like a compass. (Note: Validate the direction by comparing it to an actual compass.)
How Does the Experiment Work?
Rubbing the needle with the magnet caused the needle to become temporarily magnetized. Once magnetized, the needle had a north and south pole (like all magnets). Magnets interact with one another by either repelling or attracting each other. Once the needle was magnetized, it interacted with Earth’s magnetic field.
When the paper was placed in the water, it floated on the surface of the water and was able to move freely. At that point, the magnetized needle caused the paper to spin around until the north and south poles of the needle were in line with Earth’s magnetic field – Earth’s north and south poles. The same end of your needle should always point the same direction, despite your best efforts to make it not!
The magnetic field of a magnet is the area of magnetic force around a magnet.
More Science Fun
Magnets can be fun and educational! After doing this experiment, you’ll want to check out these other fun experiments with magnets.
- How liquids impact magnets – Follow this simple experiment to see how the magnetic force is impacted by different types of liquids.
- Paper Clip Chain – Use a magnet to make a paper clip chain. How long can you make your chain?
I hope you enjoyed the experiment. Here are some printable instructions: