*applications of electromagnets

• Electromagnets are used where permanent magnets would not be useful
• Fire doors


  the electromagnet is connected to the fire alarm and when the fire alarm is switched on, the magnet is switched off and the door closes
• Scanners in hospitals


  they use powerful electromagnets in for eg; MRI (magnetic resonance imaging) scanners used to produce images from inside the human body
• Sorting scrap metal


  the electromagnet will attract iron and steel, leaving other non-magnetic metals behind (eg; copper, aluminium, zinc).

  when the magnetic metals have been lifted, they can be moved away adn then dropped by switching off the magnet
• Toaster


  when the handle is pushed down, an electromagnet holds down a metal basket with bread in it.

  a timer turns the electromagnet off and the metal basket pops up with toast
• Electric bell


  uses an electromagnet to make a hammer move.

  when the electromagnet is on, the hammer is pulled onto the bell. the movement breaks the circuit and the hammer moves away from the bell then the circuit becomes complete again and the hammer is pulled back to the bell.

  this continues until the power supply is turned off and electric bells are used in schools, as fire alarms and door bells.
• Electric motors


  use electromagnets to change electrical energy to kinetic energy