electromagnetic induction

• if wire or magnet is moved slowly in electromagnetic induction there will be no current
• electromagnetic induction is the creation of voltage in a conductor which is experiencing a change in magnetic field
• induced voltage can be made a large as possible by

  • moving the wire / magnet faster
  • more turns on coil
  • stronger magnetic field
• AC generators make use of electromagnetic induction to change kinetic energy into electrical energy
• when a wire is moved in a magnetic field, it causes electrons to move and induces a current
• in a generator, as the coil is rotated the current reverses direction every half turn. This is called an alternating current (AC)
• in real generators, the coil is stationary and it is the magnet that rotates inside the coil of wire
• generators uses the ...

  generightor - right hand rule
• flemmings right hand rule

  • thumb - motion
  • first finger - field (magnetic field)
  • second finger - induced current
• differences between industrial a.c. generators and simple a.c. generators

  • there would be lots of turns of wire in industrial
  • the magnet spins in industrial
  • iron core in industrial
• electromagnetic induction equation:

  magnetic field + wire connected to circuit + movement = voltage
• a voltage is produced when the coil spins because the wire cuts magnetic field lines
• if the coil is spun twice as fast, the voltage would double and the frequency would double