5M10.60 - Diode PN Junction - Edison Effect

Code Number:
5M10.60
Demo Title:
Diode PN Junction - Edison Effect
Condition:
Excellent
Principle:
PN Junction Diode
Area of Study:
Electricity and Magnetism
Equipment:
0 to 20 VDC Power Supply, 0 to 150 VDC Power Supply, Diode PN Junction Circuit Board.
Procedure:

Plug the 20VDC and 150 VDC power supplies into the circuit board as indicated.  Run the filament light at 12 VDC.  You may cover the bulb with a mask or other cover so that you may easily see the LED when it turns on.  Carefully turn up the voltage on the 150 VDC power supply.  When you reach a forward bias of about 60 VDC, current will start to flow turning on the LED.

References:
  • ZhiQi Lin, Wei Zhang, and HuiJie Li, "Using Car Taillights as an Experimental Device to Demonstrate the Edison Effect", TPT, Vol. 56, #6, Sept. 2018, p. 410.

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