5H40.38 - Lorentz Force - Jumping Wire With a Twist

Code Number:
Demo Title:
Lorentz Force - Jumping Wire With a Twist
Forces on Currents in Wires
Area of Study:
Electricity & Magnetism
Pasco Wave Generator, 10 ohm resistor, laser pointer, Pasco adjustable magnet, two wire torsion app.

Hook up the apparatus with the resistor in series with the wave generator.  Carefully adjust and place the magnet so that the poles of the magnet are directly above and below the mirror.  Turn on the laser and reflect it off the mirror onto the screen, then adjust the wave generator to a frequency between 0 and 10 Hz. The twisting motion that the repelling wires apply to the mirror will be amplified by the optical lever arm.

  • Albert A. Bartlett, "Torsional Oscillations and Waves Projected on the Wall", TPT, Vol. 46, # 6, Sept. 2008, p. 338.
  • Paul Gluck, "Torsional Oscillations with Lorentz Force", TPT, Vol. 45, # 5, May 2007.
  • Bill Layton, Martin Simon, "A Different Twist on the Lorentz Force and Faraday's Law", TPT, Vol. 36, # 8, Nov. 1998, p. 474.

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