The Generator Effect

• What happens when a wire moves up through a magnetic field?

  A potential difference is induced across the wire
• What occurs to the potential difference when the wire stops moving?

  The potential difference is lost
• What happens when the wire moves back down through the magnetic field?

  The potential difference is induced again, but reversed
• What is the term for the potential difference induced in the wire?

  Induced potential
• What is induced when there is a complete circuit?

  A current is induced
• What happens to the direction of current when the direction of movement switches?

  The direction of the current switches
• What occurs if the movement of the wire stops?

  The current also stops
• What can induce a potential difference if the wire is still?

  Moving the magnetic field
• What is required for the generator effect to be observed?

  The wire must pass through the magnetic field
• What happens if the wire moves along the magnetic field?

  No induced potential difference or current occurs
• What factors affect the size and direction of the induced potential?

  • Strength of the magnetic field
  • Speed of the wire's movement
  • Shape of the wire (coiling)
• How does the strength of the magnetic field affect induced potential?

  A stronger magnetic field increases induced potential
• What effect does moving the wire more rapidly have on induced potential?

  It increases the induced potential
• How does shaping the wire into a coil affect induced potential?

  It increases the induced potential
• What happens when a magnet moves in and out of a coil of wire?

  An induced current is produced
• What happens to the direction of the current when the direction of movement changes?

  The direction of the current changes
• What occurs if the poles of the magnet are switched?

  The direction of the induced current switches
• What is the relationship between induced current and magnetic fields?

  • Induced current creates its own magnetic field
  • This magnetic field opposes the movement of the magnet
• What happens when the North Pole of a magnet is inserted into a coil?

  The coil becomes a North Pole, repelling the magnet
• What occurs when the North Pole is pulled out of the coil?

  The coil becomes a South Pole, attracting the magnet
• What does the induced current do to the movement of the magnet?

  It makes it harder to move the magnet
• What does the induced current transfer energy into?

  The movement of the current