Ammeters, Ammeter basics, Simple Ammeter, Ammeter material

An ideal ammeter has zero resistance so that the the circuit in which it has been placed is not disturbed. An ideal ammeter is a short circuit. However, as with the voltmeter, no ammeter can ever be ideal, and therefore all ammeters have some ( hopefully) small internal resistance.

An ammeter is a device that detects an electric current. With some readily available materials, you can build your own ammeter and use it to measure current produced by batteries including homemade batteries and generators.

Material

• Magnet wire, 10 meters or more of 22 gauge or higher, (available from Radio Shack). (The higher the gauge, the finer the wire, and the harder it will be to wind.)
• two small disk magnets (1 cm diameter available from Radio Shack)
• thread or fishing line
• a cardboard tube (e.g. from a toilet paper roll.)
• a Base, a piece of corrugated cardboard about 10 cm x 10 cm
  (For a more rugged meter use wood.)
• Hot melt glue (or staples)
• Aluminum foil, two 5 cm squares
• Tacks or pushpins
• Two alligator clip leads (available at Radio Shack)
• Sandpaper
• AA battery (almost any battery will work)