Let’s dive right in and explore some of the technology that Bell was using when he discovered the telephone. He would have been very familiar with the experiment we are about to do:
Materials Needed
• A paper cup (size is not important)
• Tape (can be masking, duct, or plastic tape)
• A “D” “C” or “AA” cell
• Enameled copper wire and a piece of 1 or 1 1/4″ plastic pipe or dowel
• A small magnet
• A small piece of metal screening material
• An alligator clip connector wire
Procedure
1) Make a coil of copper wire by wrapping it around a 1″ circular pipe or dowel
Make at least 10 Turns of wire and leave enough wire on each end of the coil so you have leads of 1 foot or so.
Tape the coil so it will not unravel as shown in the photo.
2) The wire ends will need to be cleaned of the enamel. Sand off at least 1″ of the wire on each end lead.
3) Tape the coil of wire to the bottom of a paper cup.
4) Place the round magnet on the center of a piece of tape and attach it to the. center of the coil.
5) Secure the tape and magnet to the cup bottom.
6) Now we are ready to test what we have made. Watch the video of how we will proceed next:
If you need help setting this up, see the picture below. One wire from cup taped to top of cell. Other wire attached to the alligator clip. The cell standing on the screen. The circuit is complete when the clip touches the screen.
PLEASE RESPOND: Place your ear on the. cup and strum the screen. Describe what you hear: mjaeger@eou.edu