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K1-41: BARLOW'S DISC

  • Magnetic Fields and Forces
  • Electromagnetic Induction

  • ID Code: K1-41
  • Purpose: Demonstrate how an electric potential difference and current can be generated when free (conduction) electrons move through a magnetic field.
  • Description: Rotating a copper disc between the pole tips of a strong C-shaped magnet, to create a vxB force on free electrons in the copper, creates a potential difference which is picked up by brushes at the center and the outside of the disc and displayed on the galvanometer. Reverse rotation of disc to invert current (center photograph).
  • Availability: Not Currently Available
  • References: http://lecdem.physics.umd.edu/images/refs/refsk.htm#K1-41
  • Loc codes: K1, D1, ME2
  • Videos-1: http://lecdem.physics.umd.edu/images/OldDemoIndex/demosk1/k1-41CCW.mpg
  • Videos-2: http://lecdem.physics.umd.edu/images/OldDemoIndex/demosk1/k1-41CW.mpg

Related Demonstrations

  • K2-64: UNIPOLAR GENERATOR
  • J6-33: ELECTROMAGNETIC GUN
  • J6-32: FORCE ON SOLENOID CORE - SMALL
  • K2-46: MAGNET LEVITATION ABOVE SPINNING DISC
  • K2-03 FARADAY'S EXPERIMENT ON INDUCTION

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