Magnetism

Cards (7)

How a motor works
A current passes through the coil
This current creates a magnetic field
This magnetic field interacts with the pernament magnetic field formed by the pernament magnet
This causes a force on the coil
The force causes the coil to rotate
The split ring commutator reverses the current every half turn to keep the coil spinning in the same direction
How a generator works
A coil is moved in a magnetic field
The coil experiences a change in magnetic field
The coil cuts through magnetic field lines
This induces a potential difference
If there is a complete circuit, a current is also induced
A loudspeaker works in the motor effect
A microphone is a device that converts sound waves into electrical signals.
A microphone works in the generator effect
How a microphone works
Sound waves vibrate the diaphragm
The diaphragm moves the coil
The coil experiences a change in magnetic field
The coil cuts through magnetic field lines
This induces a potential difference
If there is a complete circuit, a current is also induced
How a speaker works
A current passes through the coil
This current creates an magnetic field
This magnetic field interacts with the magnetic field formed by the permanent magnet
This causes a force on the coil
The current is alternating and changes direction, which changes the direction of the magnetic field and therefore the force
The changing force vibrates the cone
This causes air particles to vibrate and creates sound