One of the best parts about River Classroom is that our students can handle anything we throw at them. They love to experiment and get their hands dirty. That’s exactly what we did in class to learn about motors and generators.
After a short discussion about motors, they jumped right in. We divided into teams, and half of the teams began building motors, and half of the teams played with generators and voltmeters.
Our motors were simple- a battery attached to thick copper wires that supported a coil, suspended by thinner copper wire. Add in some magnets, and the coil spins like crazy! This only works if you have a continuous circuit, if you remember to remove the insulation on the supporting wires, and if you only remove half of the insulation on the thinner wires that hold the coil. If your wire isn’t insulated, you can color half of the arms of the thinner wire with a permanent marker.
The copper wires act as conductors and complete a circuit (Watch out- even if the coil isn’t spinning, if the circuit is complete, the wire gets hot!). The coil experiences a magnetic force because of the electrons flowing through it, and the magnet repels the coil, causing it to make half of a turn. When the coated part of the wire stops the circuit, the coil continues rotating due to gravity, where the uncoated part of the wire makes contact again. It’s incredible how fast it can spin.
Creating a working motor isn’t easy. If the wires in the coil aren’t tightly packed, it won’t work. If the wire used to support the coil isn’t attached evenly, it won’t work. If the coil isn’t balanced, it won’t work. Fortunately our students are clever and figured it out with a little prompting.
In their reflections in their science notebooks, nearly all of the students successfully explained the difference between a motor and a generator and drew figures of both. How many adults can do that?