Generators
When a wire is moved in the magnetic field of a Device that converts kinetic energy into electrical energy., the movement, magnetic field and Moving electric charges, eg electrons moving through a metal wire. are all at right angles to each other. If the wire is moved in the opposite direction, the To cause something or make it happen. A potential difference is caused or induced when a coil of wire moves in a magnetic field. current also moves in the opposite direction.
In a generator, one side of a coil moves up during one half turn and then down during the next half turn. This means that as a coil is rotated in a magnetic field, the induced current reverses direction every half turn. This is called alternating current (a.c.).
It is different from the direct current (d.c.) produced by a battery, which is always in the same direction.
Normally in a generator, the coil is fixed and mounted outside the magnet, and it is the magnet that moves. The size of the induced voltage can be increased by:
- rotating the coil or magnet faster
- using a magnet with a stronger magnetic field
- having more turns of wire in the coil
- having an iron core inside the coil
Mains electricity is an a.c. supply. The voltage it supplies to our homes is about 230 V (volts).