Magnetism and Electromagnetism

• the electromagnetic spectrum

  • radiowaves
  • microwaves
  • infared radiation
  • visible light
  • ultraviolet
  • X-Rays
  • gamma rays

  
• a magnetic field is the area around a magnet where a magnetic material experiences a force
• only iron (including steel), cobalt and nickel are magnetic
• an induced magnet is always attracted to a magnet and loses its magnetism when outside a magnetic field
• an electromagnet is a magnet that uses electricity - it can be turned on and off
• when a magnetic field of a current carrying wire (coil) interacts with that of another magnet, it produces a force known as the motor effect
• the direction of force depends on the direction of current flow and direction of the magnetic field
• if the current flow is parallel to the magnetic field, there is no force
• Fleming's left hand rule:

  
• magnetic flux density is the measure of the strength of a magnetic field, it is measured in Teslas (T)
• a solenoid is a wire wrapped up into a coil shape

  
• a permanent magnet produces its own magnetic field