P4.6 Electromagnetic Induction

• What is the generator effect also known as?

  Electromagnetic induction
• What happens when a wire moves through a magnetic field?

  It induces a potential difference in the wire
• What occurs to the potential difference when the wire stops moving?

  The potential difference disappears
• Why does the potential difference disappear when the wire stops moving?

  Because nothing is changing in the magnetic field
• What happens to the direction of the potential difference when the direction is changed?

  The direction of the potential difference swaps
• What is required for the induced potential difference to generate a current?

  A complete circuit must be formed
• What happens if the wire is kept still while moving the magnets?

  A potential difference is still induced
• What is the key idea in electromagnetic induction?

  A change in the magnetic field
• What happens if the wire moves back and forth without changing the magnetic field?

  No induced potential difference or current occurs
• How can we increase the size of the induced potential difference?

  • Increase the strength of the magnetic field
  • Move the wire or magnets more quickly
  • Shape the wire into a proper coil with multiple turns
• What is the effect of using stronger magnets on the induced potential difference?

  It induces a larger potential difference
• How does moving the wire or magnets more quickly affect the induced potential difference?

  It increases the induced potential difference
• What happens when we add more turns to the coil?

  The induced potential difference increases
• What occurs when a magnet is moved into and out of a coil of wire?

  • Induces a potential difference in the coil
  • Generates a current if the circuit is complete
  • Changes the direction of the current when the magnet's direction changes
• How does changing the direction of the magnet affect the current?

  It changes the direction of the current
• What happens if we swap the poles of the magnets?

  It changes the direction of the current
• What is the generator effect (also known as electromagnetic induction)?


  If an electrical conductor (like a wire) moves relative to a magnetic field, a potential difference will be induced across the ends of the conductor. If the conductor is part of a complete circuit, a current is also induced in the conductor.
• What is the generator effect (also known as electromagnetic induction)? But in simple terms.


  A magnetic field induces a current in a wire.
• Give 3 ways to increase the size of the potential difference generated in electromagnetic induction.


  1. Increase the magnetic field strength by using stronger magnets.
  2. Move the wire or magnets faster.
  3. Add more turns to the coil.
• When can be said about the direction of the magnetic field produced by an induced current?


  The direction of the field is such that it opposes the change that induced the current.