the two opposite regions in a magnet, where the magnetic field is concentrated; can be north or south
Permanent magnet
an object that produces its own magnetic field
Induced magnet
an object that becomes magnetic when placed in a magnetic field
Flux density
a measure of the density of the field lines around a magnet
Solenoid
a coil of wire partially surrounding an iron core, which is made to move inside the coil by the magnetic field set up by a current; used to convert electrical to mechanical energy
Uniform
unchanging in form, quality or quantity; regular
Electromagnet
a magnet consisting of an iron or steel core wound with a coil of wire, through which a current is passed
Motor effect
the force experienced by a current carrying conductor when it is placed in a magnetic field, which is used to create movement in electrical motor
Flux density
a measure of the density of the field lines around a magnet
Commutator
a device used to reverse the direction of flow of an electric current in motors and generators
Generator effect
to induce a potential difference (voltage) using magnetic fields and conductors
Induced
to produce (a potential difference) or transmit (magnetism)
Alternator
an electrical machine that uses a rotating magnet inside a fixed coil of wire to generate an alternating current
Dynamo
a device that uses a rotating coil and a fixed magnet to convert mechanical energy into a direct curren
Microphone
a device that uses the generator effect to convert soundwaves into electrical signals
Transformer
a device that transfers an alternating current from one circuit to another, with an increase (step-up transformer) or decrease (step-down transformer) of voltage
