Studied by 5 peopleForce equation(letters)
BI1
Force equation
magnetic flux density x current x length
South and South
attract
North and South
repel
What is a magnetic field
A region where other magnets or magnetic materials experience a force
magnets produce
magnetic fields
loudspeakers and headphones both use
electromagnets
Find which way a force is acting using
flemings left hand rule
current
in a magnetic field experiences a force
permanent magnet
· The coil surrounds one pole of a(n) ________, and is surrounded by the other pole, so the current causes a force on the coil (which causes the cone to move)
poles north
All magnets have two ________ and south.
motor effect
The ________ can happen when you put a current- carrying wire in a magnetic field.
Compasses
________ show the directions of magnetic fields.
spilt ring commutator
· The ________ is a clever way of swapping the contacts every half turn to keep the motor rotating in the same direction.
magnitude
The ________ (strength) of the force increases with the strength of the magnetic field.
right angles
The force always acts at ________ to the magnetic field of the magnets and the direction of the current in the wire.
coil of wire
Forces act on the side arms of a(n) ________ thats carrying a current.
Output pd of transformer equation
vp/vs = np/ns
Output pf of transformer equation two
vsis = vpip
Step up transformer
step the potential difference up
Step down transformer
step the potential difference down
Note
Flashcard