How do Electric Motors work?

The concept of electric motors is really straightforward: all you have to do is put electricity into one point and that the other point a metal rod will rotate which provides you with the power to drive an automobile.  In order to understand exactly how an electric motor works in practice, we will have to look at past times.  The basic understanding comes from electricity being inverted into motion.

Assume you take a length of normal wire, make it into a circle, and lay it between the poles of an effective, durable horseshoe magnet. When you attach the tow end of the wire to a battery, you will soon find the wire hop up.  Scientists have effectively explained how this bounce is possible.  This is where the magnetic flied comes in, the current creates a magnetic field along the wire. And if by any chance you place a permanent magnet near to the magnetic field, the temporary magnetic field will interact with the permanent magnetic field. 

With common knowledge one would know that two magnets either repel or attract when they are place next to each other. A similar way, the impermanent attraction around the wire attracts or repels the permanent magnetism from the magnet, and that is the same thing that causes the wire to hop.

How an electric motor works—in theory

Let us make a U-shaped loop so that there will be effectively two parallel wires running through the magnetic field. The electric current will move away from us while the other one will allow the current to come back again. According to Fleming’s Left Hand Rule, it states that the two wires will allow the current to flow in opposite directions.

If we left this arrangement the result will be a rotation of the current and we will be close to having ourselves an electric motor. However once the coil reaches the vertical position it will happen to flip over so that the electric current will flow through in the opposite direction. Therefore the forces on each side of the coil would reverse.

How an electric motor works—in practice

The electric current that flows in a constant reverse is better known as an alternating current (AC). We usually use this kind of current in small battery-operated motors that we use around the house. A recommended solution is to add a component which is called a commutator to the end of the coil. A commutator is a metal ring which divides into two separate halves; its function is to reverse the electric current in the wire each time the coil rotates through half a turn.  Therefore with the presence of a commutator in place, the electricity flows through the circuit and this allows the coil to rotate continually in the same direction.

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