the motor effect

• What does a current flowing through a wire produce?


  Its own magnetic field
• How do we represent the magnetic field around a current-carrying wire?

  As concentric circles around the wire
• What does the letter B represent in magnetism?

  Magnetic field
• What is the motor effect?

  When a wire in a magnetic field experiences a force
• What is the equation for the force on a wire in a magnetic field?

  F = IBL
• What does the variable B represent in the equation F = IBL?

  Magnetic flux density
• When does the equation F = IBL only work?

  When current and magnetic field lines are perpendicular
• How do you determine the direction of the force on a wire?

  Using Fleming's left-hand rule
• What does your thumb represent in Fleming's left-hand rule?

  Direction of the force
• What happens if the wire is parallel to the magnetic field lines?

  It experiences no force
• How can you measure the size of the force on a wire?

  Using a balance to measure the magnet's force
• What is the purpose of a split ring commutator in a motor?

  To reverse the current every half turn
• How can you make a motor turn faster?

  Increase current, use a stronger magnet, or add more turns
• What is a loudspeaker essentially considered?

  A motor that moves back and forth
• How does a loudspeaker produce sound waves?

  The coil vibrates, moving the speaker cone
• What is the relationship between a moving wire and a magnetic field?

  A moving wire induces a current in a magnetic field