When we hear the word “motor” it may sound a bit technical and very involved. This is because motors are used in so many machines that do amazing things. Think about all of the motors that are in our homes today: the blender, the refrigerator, mixer, the vacuum cleaner, washer, dryer, any type of fan, and so many more items that we have in order to live comfortably from day to day. And these are just small motors; there are cars, trains, wind turbines, large pumps, and power plants that have larger motors. Either way, the mention of the word “motor” can be quite intimidating.
So, What Exactly is a Motor?
A motor is a machine that takes electrical energy and turns it into mechanical energy. So what is mechanical energy and why do we need it? Well, mechanical energy is found in every moving object. Powered by a motor or not, if an object is moving, it has mechanical energy. The common machines that have motors use this mechanical energy to produce work and to get things done. When we write with a pencil, we are utilizing mechanical energy. When we throw a ball, we are using mechanical energy. Any movement uses this most familiar energy type. Of course, there are more complex types of mechanical energy, such as a rocket launch, and, well, that requires the use of motors.
The DC Motor
One common type of motor, and usually the one we hear the most about, is the DC motor. And, one very crucial part of this particular type of motor is the magnet. So, we must reflect on our knowledge of magnets for this. We know that a magnet has a positive side and a negative side, and when you try to put the negative sides of two magnets next to each other they repel. This can actually be felt. The same goes for two positive sides. This magnetic field (or force) is needed for the motor to work. The same force exists when a positive side is put beside a negative side, except this force attracts the two sides.
Another crucial element needed is a coiled wire, such as copper wire. This wire is wrapped (or coiled) and if this wire carries an electric current (a direct current), then a magnetic field of attraction and repulsion is wire carrying an electric current is formed into a series of loops, the magnetic field can be focused in the loops of the coil. The magnetic field is quite strong, and even stronger if the wire is wrapped around a "core" of highly magnetic material, such as iron, nickel, or cobalt.
Once you have a direct current flowing into the wire, it creates a force, and since the wire is looped, the force will happen in opposite directions. These forces, attracting and repelling, will create a turning, or torque, thus making the motor spin. Any DC motor must have an electromagnet to work, and is usually located in the center of the motor.