Electromagnetism

• Moving Charge


  Creates a Magnetic Field
• Magnetic Field created by wire


  1. Current flowing through wire

  2. Magnetic field lines perpendicular to wire

  3. Magnetic field strongest at centre of wire

  4. Magnetic field direction changes as you move around wire
• Solenoid


  Coil of Wire
• Magnetic field of solenoid

  • Strong and uniform
  • Same as magnetic field around a bar magnet
• Adding iron core to solenoid

  Increases magnetic field strength
• Electromagnet

  Magnetic field can be turned on and off with an electric current