Electric motors

• What principle do electric motors use to operate?

  The motor effect
• What happens to a current-carrying coil in a magnetic field?

  • Forces act on the coil's arms
  • Causes the coil to rotate
  • The rotation is due to opposing forces
• What does the split-ring commutator do in a d.c. motor?

  Swaps contacts every half-turn
• How can the direction of a motor be reversed?

  By swapping current polarity or magnetic poles
• Which rule helps determine the direction of coil rotation in a motor?

  Fleming’s left-hand rule
• What are the steps to determine the coil's rotation direction?

  1. Draw current arrows (positive to negative)
  2. Apply Fleming’s left-hand rule
  3. Determine the direction of force (motion)
• What is the outcome when the coil's current direction is reversed?

  The coil's rotation direction reverses
• What everyday items commonly use electric motors?

  Food mixers and hair dryers
• What are some applications of electric motors?

  • Food mixers
  • DVD players
  • Fans (hair dryers, laptops)