The motor effect

• What is the motor effect?

  The interaction of magnetic fields causing force
• How can you calculate the size of the force generated by the motor effect?

  Using the equation: force = magnetic flux density × current × length
• What does Fleming's left hand rule help determine?

  The direction of the force on a conductor
• For which students is this material intended?

  High-tier students only
• What happens when a wire carrying current is placed in a magnetic field?

  The wire experiences a force due to interaction
• What direction does the force act when a wire is placed in a magnetic field?


  Upward direction
• What is the equation to calculate the force acting on a wire?

  Force = magnetic flux density × current × length
• What does magnetic flux density measure?

  The strength of the magnetic field
• If a wire has a length of 2.5 meters, current of 1.5 amperes, and magnetic flux density of 0.05 Tesla, what is the force acting on it?

  0.19 Newtons
• What factors affect the size of the force in the motor effect?

  Magnetic flux density, current, and length
• How do you apply Fleming's left hand rule?

  Thumb points motion, first finger magnetic field, second finger current
• What happens if the conductor is parallel to the magnetic field?

  It will not experience a force
• What are the steps to use Fleming's left hand rule?

  • Place thumb, first finger, and second finger at right angles
  • Point first finger in direction of magnetic field (N to S)
  • Point second finger in direction of conventional current (positive to negative)
  • Thumb indicates direction of motion (force)
• What is the result when a conductor is at right angles to the magnetic field?

  It will experience a force
• What are the key components of the equation for calculating force in the motor effect?

  • Magnetic flux density (in Tesla)
  • Current (in Amperes)
  • Length of the wire (in meters)