motor effect

• the motor effect turns electrical energy into kinetic energy
• motor effect examples: washing machine, electric fan, drills
• motor effect equation: magnetic field + current carrying wire = movement
• predict motor effect by Flemings left hand rule
• Flemmings left hand rule

  • Thumb = motion
  • first finger = field (magnetic field)
  • second finger = current
• if the direction of the current or the direction of the magnetic field is reversed then the wire will move in the opposite direction
• if the current flows parallel to the magnetic field direction then the wire wont move
• size of force formula F = BIL

  F = force in newtons

  B = magnetic field strength in teslas

  I = current in amps

  L = length of wire in metres
• electric motors transfer electrical energy into kinetic energy
• in an electric motor a coil of wire rotates between two opposite magnetic poles
• in an electric motor the current flows through the wire. Because of the left hand rule, one side moves up and the other side down so it spins
• in an electric motor, the split ring commutator reverses the current every half turn which makes sure one side of the coil always moves up and the other side down
• split ring commutator reverses direction of current every half turn
• brushes makes sure electrical contact is maintained