I am taking an electromagnetics course this semester, and our first project is getting into groups and making a human-powered generator that can light a bulb. It is actually a pretty fun project. We have to use “junk” that we find, and can spend no more than $10/person in the group. There are 5 people in our group, so I don’t think the money specification limits us very much. So far it looks like we will spend a total of $5 (for the entire group, not per person.)
Here are some interesting and useful tidbits we have learned so far:
- Don’t use speaker magnets. They may be strong, but they are heavy and their strength is actually pretty low relative to their volume and mass. You can get really strong magnets that are much smaller.
- There are millions (not literally) of things around the house that you can use for the spool that you wrap your wire around. We thought of using a solder spool, but have decided to use part of a fan duct from my computer case. Computer case fans (with the fan part cut out) would have worked equally well.
- Make sure you know which direction the magnets are supposed to spin relative to the wire coils. Most people (including everyone in our group) think the magnet’s poles should spin with the direction of wire coils, when it should actually spin against the grain. Think of the relationship between magnetic and electric fields – the “right-hand rule.”
I will continue updating this post as the project progresses.