Electromagnetism

• When current flows through a wire, a magnetic field is induced.

  
• A Solenoid is a coil of wire that produces a magnetic field.

  
• Increasing the strength of a Magnetic Field in a Wire:

  
  

  • Adding more coils
  • Use of an Iron core
  • Increase Current

  
• Electromagnets are used in doorbells and Cranes
• Aluminium is a conductor. It is NOT magnetic.
• Right-Hand Rule.

  A) Magnetic Field

  B) Current

  
• Solenoids are Strong and Uniform.
• If there is NO current, there is no magnetic field.
• If you reverse the direction of current, the direction of the magnetic field ALSO changes.

  
• The magnetic field is stronger closer to the wire.

  
• Electromagnets are useful because we can turn them on and off.