5K10.30 Driving/Sensing Coils Light Lamps

PURPOSE: To demonstrate induced currents.

DESCRIPTION: Two identical, very large coils with many turns of wire are placed coaxially a few centimeters apart. The "driving" coil is connected to a flashlight battery; the "sensing" coil is connected to a lecture-table galvanometer. When current from the battery is established in the driving coil, the galvanometer kicks, then subsides. Interrupting the current produces another kick, in the opposite direction. When the current is flowing steadily, one or both coils can be moved to produce deflection again.

SETUP TIME: Minimal

COMPONENT LIST:

    


  1.  Large coils					EM Shelves


  2.  Flashlight battery				Battery Area


  3.  Lecture-Table Galvanometer			EM Shelves


  4.  Magnet (optional)				EM Shelves - Magnet Area

SUGGESTIONS: See Vincent's 2122 Demonstration Booklet for further instructions.

REFERENCES: 2122 4.71, 4.74; PIRA 5K10.30

OTHER NOTES: Also, various sheets (wood, aluminum, steel) can be interposed between the coils. And it's always worthwhile to plunge a bar magnet into the sensing coil - it produces quite a large deflection.