Can we make a magnet fall in slow-motion? Is copper magnetic? How do we make electricity?
All great questions…Let’s find out!
You will need:
- A straight copper pipe (at least 100cm in length)
- Small neodymium magnets *adult supervision required*
- A stopwatch/egg timer *optional*
- Try holding a magnet against the outside of the copper pipe and let go – it doesn’t stick! That’s because copper is not magnetic.
- Now try holding the copper pipe upright and drop the magnet through the pipe – the magnet should take several seconds to appear at the bottom of the pipe.
- You can try timing how long the magnet takes to fall to the floor inside the pipe and outside the pipe with a stopwatch or egg timer.
- Longer or thicker copper pipe will slow the magnet down even more.
The science bit:
- Inside everything, there are electrons. If these electrons are facing or moving in a certain way they produce electricity.
- Copper is not usually magnetic, so when a magnet is brought close to the copper pipe nothing happens. But when a magnet is in motion (when it’s moving) inside the copper pipe the electrons in the magnet pull on the electrons in the copper pipe which creates a small bit of electricity! This electrical energy doesn’t come from nowhere – the magnet has to convert some of its momentum (kinetic/movement energy) into electrical energy, and that’s why the magnet slows down while it’s falling through the copper pipe.
- We make most of our electricity using large magnets and copper!