Electric motors are useful for a number of reasons and are necessary where fuel powered motors cannot perform. Many electric motors are restricted by operating on either alternating current (AC) or direct current (DC) power. However, universal electric motors are capable of operating using both AC and DC power. So, why are some electric motors limited by either AC or DC and what makes universal motors different? Many items used frequently if not daily have universal electric motors that power them. They are utilized because of a vast amount of advantages, but like all things there are also some disadvantages.
Let’s imagine for a moment a world without friction, which is, simply put, the force resistant to movement when any two objects rub against each other. Wait a second… that’s just too chaotic! If you think the world is a disaster now, just take away friction and… boom! Everything crashes into everything because there’s no force to stop it. So, here’s what I’ll do: I’ll just take away the friction between your posterior and what it’s sitting on… I need a good laugh today. You can’t stay put can you? Keep slipping and sliding, huh?