Homemade Battery Project
My homemade battery is a soda based battery, combining soda (coke), aluminum, and copper. The top of the cup is the anode and the bottom is the cathode. The copper and aluminum transfers electrons to each other using the electrolyte, causing this battery to work when touched with the voltage meter.
Electromagnetic Speaker
This is an electromagnetic speaker made out of a paper cup, a coil of wire, a magnet, and old headphones. It works by attaching a coil of wire to a paper cup, and having the magnet come into contact with the coil, while the wires underneath the skin of the headphones come into contact with the sanded copper wires hanging from the coil. The magnet sends electrical current to the exposed metal allowing that metal to become temporarily magnetized which then creates an electromagnetic field. When connected to the wires within the headphones, the electrical current flows through them as well, allowing sound to then come out of the cup when connected to a device.