The electric motor

• Which rule helps determine the direction of the force in the motor effect?

  Fleming's left hand rule
• What should you be able to describe by the end of the video?

  How an electric motor works
• What is the motor effect?

  A force on a current-carrying conductor in a magnetic field
• What happens to a loop of wire carrying current in a magnetic field?

  • Experiences a force on both sides
  • Left side force acts upwards
  • Right side force acts downwards
  • Causes clockwise rotation
• What happens to the loop when it rotates to 90 degrees?

  It stops rotating
• What occurs when the loop rotates beyond 90 degrees?

  Forces push the loop back to 90 degrees
• How can the problem of stopping rotation at 90 degrees be solved?

  By switching the direction of the current
• What device is used to switch the direction of the current in an electric motor?

  Split ring commutator
• What is the function of the split ring commutator?

  • Switches the direction of the current
  • Allows continuous rotation of the motor
  • Connected to conducting brushes
• What happens to the current for a tiny fraction of a second during rotation?

  The current switches direction
• What effect does switching the direction of the current have on the forces acting on the loop?

  Left side force acts upwards, right side downwards
• Where can you find more questions on electric motors?

  In the vision workbook
• Who is the intended audience for the video?

  Higher-tier students
• What does the split ring commutator consist of?

  A split metal ring
• What do the conducting brushes do in an electric motor?

  Allow electric current to pass onto the ring
• How does momentum affect the wire's rotation in the motor?

  It keeps the wire turning after current switches