DC motors consist of a pair of permanent magnets within them and a split ring (also called a commutator). These are the two key features of DC motors which distinguish them from the AC motors. With complex design and more technicalities involved in the production, DC motors are more expensive to make. The speed of a DC motors depends upon the current supplied to them and hence, these motors are best to use when you require a variable speed motor.
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AC motors use electromagnets, which are not permanent magnets and only create a magnetic field when electric current passes through them. These types of motors have simpler design and fewer parts and hence, are cheaper to make. AC motors don’t use any split rings or brushes and are more reliable than DC motors. These motors run on a fixed speed, regardless of the current being supplied to them.
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