Section 6 - Electromagnetic Induction Flashcards
What is electromagnetic induction?
The creation of a voltage (and maybe a current) in a wire which is experiencing a change in Magnetic field.
What is the dynamo effect?
The use of electromagnetic induction to transform kinetic energy into electrical energy.
What are the two ways you get EM induction?
An electrical conductor moves through a magnetic field (coil of wire often used)
The magnetic field through an electrical conductor, changes (gets bigger or smaller of reverses).
What can you use to show the magnitude and direction of the induced current?
Using an ammeter connected to the conductor.
What are the ways you can get a bigger voltage?
The strength of the magnet
The speed of movement
The number of turns on coil
What happens if the direction of movement is reversed?
Then the induced current/voltage will be reversed too.
Describe how an A.C generator work?
Generators rotate the coil in a magnetic field.
Their construction is pretty much like a motor.
As the coil spins a current is induced in the coil. This current changes direction every half turns.
Instead of having a split ring commutator, they have slip rings and brushes so that the contact doesn’t swap every half turn.
This means they produce alternating current voltage.
How do power stations make their electricity.
They use ac generators they just get the energy needed to turn the coil in different ways.
What do faster revolutions produce?
More peaks but also higher overall voltage.
