Plastic Cup Speaker

While minding my own business on a Friday afternoon a couple of weeks ago, a group of students came to my office. They were having some trouble with an assignment for 5th graders – make a yogurt cup speaker.

During the testing, an important lesson was learned. They were using a coil of copper wire with little resistance (0.01 Ohm) Рbut often commercial speakers have a resistance of 4 or 8 ohms. By using a wire coil with less resistance than this, they may have damaged their radio. If it is indeed damaged, it will not be the first loss in the name of science.

With the lessons learned, I created a small speaker out of a plastic cup using a strong mini magnet (McGuckins), a coil of wire (found around the lab), and the cup from my lunch at Tokyo Joes (Dark Chicken Bowl – best deal):

Note: If shave and a haircut still only costed 2 bits, my shaggy dome would probably be less unkempt.