During our stay at home time, I strive to share activities that you can do without shopping. However, I've been pretty excited about this simple motor activity, and try as I might I was not able to figure out a way to do it entirely out of household supplies. I decided to post it anyway, because I'm that excited about it, and perhaps you do have the supplies at home after all. And if not, you can at least enjoy the video below that demonstrates my version.
An electric motor works because of the interaction between the electric and magnetic fields. Electricity moving through coiled wire will produce enough of a magnetic field to be alternately attracted and repulsed by a nearby magnet, and the combination of these forces cause it to spin. The motor that I show here is mostly for demonstration purposes, i.e. it is not strong or stable enough for practical application. However, it is a great way to explore the challenges and possibilities of this set up.
Here's what I used:
The wire was the sticking point for me: I doubt people have it lying around your house but I tried lots of other things (pipe cleaners, paper clips) and they didn't work. I'd love to hear if you have a different idea of a household item that would work for this! The red-handled tool is wire strippers, but they can also be used to cut wire. For this, they aren't totally necessary; I just used them to cut the wire.
So here's how I made the motor:
1. Cut a piece of ire 12-18" long, and coil it neatly, leaving about 1-1/2" on each side. The glue stick is not essential, just happened to be handy and about the right size.
2. Wrap the ends so that they hold the coil together. The ends should be directly across from each other.
3. Attach safety pins to the battery with either a rubber band or tape. I used electrical tape but masking tape would work too. I found that rubber bands allow the safety pins to slip around, but they would also work.
4. Put the ends of the coiled wire through the safety pin loops. I found that I needed little flags of tape on the ends to keep the wire from slipping out when it started spinning. Once it is in place, electricity will be running through it. Though it isn't enough electricity to hurt you, the wire will get warm. Also, the battery will run out if you leave it like this for too long, so be sure to disassemble if you aren't running the motor.
5. To make the motor spin, bring the coiled wire very close to the battery without touching it. Usually you have to start it with a gentle flick. You will probably have to experiment with positioning quite a bit. See video for how, and also for an explanation of the science.