Electromagnetism / Magnetism Flashcards
______ hand generator rule
right hand generator rule
_____ hand motor rule
left hand motor rule
what does each finger do in Flemming’s rule?
Thumb = motion of force
FIrst FInger = magnetic field
seCond = current
What does a split ring commutator do?
It reverses the direction of current flow each half turn causing alternating current (AC)
What are lines of flux?
magnetic Field Lines
Magnetic metals 4x
nickel, iron, steel, cobalt
What is electromagnetic induction?
The creation of emf due to a magnet passing an electromagnet.
What is trhe motor effect?
When the current in a wire is in presence of a magnetic field a force is produced
What is the generator effect?
When a wire moves across lines of flux, causing emf to be induced and therefore a current to flow.
How do you find the poles of an electromagnet?
Right hand grip rule. thumb = north. fingers curl in direction of current
What is a solenoid
a COIL OF WIRE.
Whats the purpose of brushes in a motor and generator?
Used in a SRC to enable a continuous connection = constant current flow.
What’s the purpose of brushes in a motor and generator?
To avoid sparks caused by current flow.
What happens to domains in a magnetised material?
The material gains poles, arrows point in the same direction (N-S), temporary magnetic field and therefore a temporarily induced magnet.
Current in circuit, + to - or - to +
+ to -
