Remember, when we plug in a blender, the electricity is used to make an electromagnetic force in the motor  * Like an ordinary magnet – electromagnets obey the rule that like poles repel and unlike poles attract  *  this is the basis of one of the most useful machines in the modern world: the electric motor  *  A basic motor consists of a coil of wire, like a solenoid, but on a long rod that is able to spin around  *  this coil is the armature and two poles of a permanent magnet are on either side of the coil  *  When we switch on the electricity – the armature becomes an electromagnet with its own poles  *  If the electromagnet’s north pole is near the permanent magnet’s north pole – these two magnetic forces will repel  *  The armature’s north pole is attracted to the permanent magnet’s south pole which is on the other side  *  this makes the armature spin around for a half turn  *  Now comes a neat invention – a device called the commutator serves as a switching device on the shaft  *  A commutator is a round metal collar or ring that has been divided into two halves  *  each collar is joined to one end of the armature wire  *  Two wire brushes (contacts) press on either side of the commutator and feed electricity to it and the armature  *  Best to take this next happening slow – because in reality it happens very fast  *  As the armature spins half a turn – the commutator contacts move around half a turn  – so that in effect, they exchange brushes  *  This reverses the electrical current!!  *  When the electrical current is reversed  – the armature’s magnetic poles are also reversed  *  It’s north becomes south and repels the nearby south pole of the permanent magnet  *  the same push-pull forces happen again – making the armature spin further – and the commutator reverses the current again  *  the armature keeps spinning as the commutator keeps switching the current  *  This causes the electric motor to turn around  * This allows the shaft of the electric motor to keep turning around  *  the electrical energy has been changed to kinetic or movement energy and can blend our mixtures when a blade is attached to the turning rod  **  I need a break

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