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Lecture Demonstrations Laboratory


The Demonstrations Manual


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Electrostatics
Electric Fields And Potential
Capacitance
Current and Resistance
Electromotive Force And Current
DC Circuits
Magnetic Materials
Magnetism
Inductance
Induction
1x 2x 4x Coils and Bar Magnet
Hanging Ring and Magnet
Flash Bulb Coil
LED Coil
Eddy Current Pendulum
Lenz's Law and Eddy Currents
Eddy Current Tube
Jumping Ring
Eddy Current Levitation
Eddy Current Levitation 2
Eddy Currents 2
Transformers
Electric Motor
Hand Crank Generator
Bicycle generator
Complex Circuits
Semiconductors And Tubes
Transmission Lines and Antennas

Transformers

Purpose:

To demonstrate the basic operation of a transformer and some related phenomena.

Procedure:

This set-up can be used in many different ways, the most dramatic being "Jacob's Ladder". Using the 250 turn winding as a primary and the 23,000 turn as a secondary, a voltage of about 10 K volts is produced. When the copper wires are placed at the output of the secondary and the juice turned on, an arc will form between the wires and climb upwards until the distance between the wires is too great whereupon the arc will dissipate and another will immediately form at the bottom again, repeating the process. The light socket can be plugged into the secondary and lit, or different primaries and secondaries can be used with the variac to measure different voltages and currents.

Comments:

If you have a suggestion for the use of this demo which might benefit others, you can enter it below.

Equipment:

  • Connecting Wires
  • Jacob's Ladder
  • Leybold transformer apparatus
  • Light Socket
  • Variac