How to Build a Galvanometer

First you need to gather up all of the materials you will need. Below is a list of the following items needed to conduct this project: • A battery power pack • A compass • A strip of 3” x 5” metal from a can • The floating needle from Oersted’s Experiment • #22 insulated copper wire • 1” X 3” cardboard strip • A switch • 4 nails Are you ready? Let’s get started. Wrap wire around the floating needle (the floating needle needs to be set up like the one in Oersted’s Experiment) dish 5 times. Connect one wire end with the insulation stripped off to the switch then connect another wire end with the insulation stripped off from the switch to the negative terminal of the battery. Connect the wire from the dish to the positive terminal of the power pack. Close the switch and observe how far and fast the needle turns. What happened? Did it work? It should have. If not, make sure your wires are connected securely. You could also try wrapping the wire around the dish 5 more times to see if the needle turned farther and faster than before. Luigi Galvani invented the galvanometer. He happened to invent this device by discovering that the leg of a frog twitched when touched by an electrically charged scalpel.