Words of this topic
Magnetic field: the space around a magnet or a current-carrying wire where its magnetic effect can be felt.
Magnetic lines of force: lines drawn to show the direction and strength of a magnetic field. Where they crowd together, the field is strong.
Motor effect: motion produced in a current-carrying wire placed in a magnetic field.
Electric motor: a device that changes electrical energy into turning motion by the motor effect.
Coil: many turns of insulated wire wound side by side.
Core: the piece the coil is wound on. In a motor it is soft iron.
Permanent magnet: a magnet that keeps its magnetism all the time. In a motor it provides the fixed field.
Shaft: the rod the coil is fixed on. It turns with the coil and drives the fan, pump or blade.
Alternating current (a.c.): current whose direction keeps reversing.
Direct current (d.c.): current that flows in one direction only, such as the current from a battery.