Induced Potential

• If an electrical conductor (wire) is moved through a magnetic field a potential difference is induced across the ends of the wire
• If a complete circuit is moved through a magnetic field a current is induced. This is the generator effect
• An induced current generates a magnetic field that opposes the original change, either the movement of the conductor or the change in magnetic field
• The generator effect is used in an alternator to generate ac and in a dynamo to generate dc
• Microphones use the generator effect to convert the pressure variations in sound waves into variations in current in electrical circuits
•  The maximum potential difference or current on a alternator and dynamo can be increased by:

  • increasing the rate of rotation
  • increasing the strength of the magnetic field
  • increasing the number of turns on the coil
• Alternator

  
• Dynamo