5C30.20 - Spark a Capacitor

Code Number:
5C30.20
Demo Title:
Spark a Capacitor
Condition:
Excellent
Principle:
Energy stored in a Capacitor
Area of Study:
Electricity & Magnetism
Equipment:
5000 V DC power supply, Oil-filled capacitor (2 mfd 5000 vdc), Large, plastic-handled screwdriver, Large Ball Peen Hammer
Procedure:

Connect the capacitor to the 5 KV power supply as shown. Turn on the power supply and push up the slide switch slowly so that the capacitor charges at a constant rate as shown on the meter on the power supply. When it reaches about 4500 volts, pull the slide switch down and shut off the power supply before discharging, so as not to damage the power supply. With the hammer or the screw driver discharge the capacitor.

The camera flash units are also a version of energy stored in a capacitor.  It will take up to 10 seconds for the capacitor to charge once the unit has been turned on.  

References:
  • John Carlson, "The Kodak One-Time-Use Flash Camera", TPT, Vol. 42, #6, Sept. 2004, p. 375.
  • Ed-6, 8:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • E-210:  "Sphere Gap Plus Capacitor",  DICK and RAE Physics Demo Notebook.
  • Borislaw Bilash II, “Deliverance“, A Demo A Day – A Year of Physical Science Demonstrations, p. 277.


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