induced potential

• what are microphones

  • convert sound waves into electrical currents
  • sound waves reach the microphone, causing the diaphragm to vibrate
  • This causes the coil to move back and forth through a magnetic field , producign an AC Pd
• what is the generator effect

  • uses motion to generate electricity
  • a wire cuts through the magnetic field and produces a pd
  • a current is induced by the conductor in the circuit
  • AC
• how to change the size of the pd

  • use stronger magnets
  • move the wire more quickly
  • shape the wires into more coils - more pd
• what does a step up transformer do

  • increase the voltage to 400000V
  • this minimises energy loss
• what does a step down transformer do

  • decreases voltage for safety
  • 230 V
• what is the size of induced potential determined by?

  • the speed at which the wire is moved through the MF
  • the number of turns on the coil
  • the size of coils
  • the strength of mf
• what is Lenz law

  • the direction of an induced potential difference always opposes the change that produces it
• how can the generator effect be used?

  • generate an AC in an alternator
  • generate a DC in a dynamo
• what is an alternator

  • converts energy from motion into an electrical output wiht an AC
  • an alternating PD is geenerated
• how do microphones work?

  • convert sound waves into electical current
  • sound waves reach the microphone which causes the diaphragm to vibrate
  • this causes the coil to move back and dorth which cuts through the MF to produce a current
  • this induces a potential
  • AC current
• microphoen

  
• what does a basic transformer consist of

  • primary coil
  • secondary coil
  • iron core - easily magnetised
• how does a transformer work

  • AC is supplied to primary coil
  • current continually changes direction - produces a changing magnetic field around the primary coil
  • iron core is easily magnetised, meaning the changing magentic field passes through it
  • there is now a changing magnetic field in the seconfary coil which indueces an alternate PD
• what is a step up

  • increases PD
  • more turns on secondary coil
• what is a step down

  • decreases PD
  • less turns on secondary
• how to increase MF in a solenoid

  • mroe coils
  • stronger current
  • add iron core
• what is an electromagnet

  • solenoid +iron core
• how to increase force

  • increase current
  • use stronger magnets
  • place the wire at 90 degrees
• how to increase speed of an EM

  • increase current
  • use stronger magnet
• how to change direction of rotation of a EM

  • alternate current
  • alternate direction of MF
• how to increase force of an EM

  • increase current
  • increase MF
  • more coils