Electromagnets

• When a current passes through a wire, a magnetic field is generated. This can be proven by using a compass.
• The magnetic field is strongest closest to the wire
• A solenoid can increase the strength of the magnetic field
• How can we increase the strength of a magnetic field produced by a solenoid?

  • increase the current to increase size of field
  • increase number of turns in coil
  • place a soft iron core
• A solenoid with an iron core is called an electromagnet. They can be turned on or off and we can change the strength of the magnetic field
• Conventional current flows from positive to negative