Topic 13 Flashcards
What is induced current?
Induced current is the current produced by a moving magnet in a coil of a wire.
What happens to the current when a magnet is moved in the opposite direction?
The current is induced in the opposite direction
The larger the..
Current through the wire or the closer the stronger the field
Factors that effect the size of the current/voltage
Number of coils of wire
Speed of rotation
Magnetic field strength
What is an solenoid?
A solenoid is a long coil of wire
What happens after every half turn?
The current switches direction, it produces Alternative current .
What is electromagnetic induction?
The induction of a p.d in a wire which is experiencing a change in magnetic field
What is an electromagnet?
A magnet with a magnetic field that can be turned On and off using a electric current.
How can you increase the field strength?
By putting a block of iron in the centre
What is the motor effect?
When a current carrying conductor is placed between a wire two magnetic fields interact, to experience a full force it has to be at 90*
What do step up transformers do?
Increase the voltage and decrease the current
What do step down transformers do?
Lower the voltage and increase the current
How do transformers work?
—They use step up transformers to increase the voltage minimising energy loss
-Use step down to decrease voltage before entering are homes to make it safer
What is the role of a transformer?
Increase or decrease electricity
What happens when an alternating p.d is applied across the primary coil?
It produces an alternating magnetic field.
