Topic 6 - Electromagnetic Induction Flashcards
what is electromagnetic induction?
the creation of a voltage in a wire which is experiencing a change in magnetic field
what is the dynamo effect?
using electromagnetic induction to generate electricity using energy from kinetic energy stores
what are the two situations where you get electromagnetic induction?
- an electrical conductor moves through a magnetic field
- the magnetic field through an electrical conductor changes
how would you test the dynamo effect?
by connecting an ammeter to a conductor and moving the conductor through a magnetic field
what happens to the dynamo effect if direction of movement is reversed?
the induced voltage will be reversed too
how would you get a bigger voltage in the dynamo effect?
increase the strength of the magnet
increase the number of turns on the coil
increase the speed of movement
what do generators do?
rotate a coil in a magnetic field
how is current induced in a generator?
as the coil spins, a current is induced in the coil. this current changes direction every half turn
do generators have split ring commutators?
no, as they dont need to change contacts every half turn
what are ac generators used in?
power stations use them to produce electricity
