Electricity

Not very clear terms invented by physicists to describe the electric current. The current is defined as constant and variable. And their properties and impact on the environment are different. But if you look closely. The DC in the beginning behaves the same as the alternating current. At the moment of inclusion.
I want to draw your attention to the fact that when the chain closes, changes occur in it. Something must be closed. Conventionally called this a current sweep. When the process is established in the whole chain, changes do not occur. We call this direct current.
With alternating current, there is a constant process of circuit closure. They achieve this in many ways. You can always close or open the circuit. And you can change the direction of the closure, which was the creation of the generator. In which the rotor rotates, thereby creating a constant change in direction of circuit closure.
The scheme is such,

closes-opens-changes direction-closes-opens-changes direction.

As a result of the circular motion, this process has a sinusoidal character.
The difference between direct current and variable is no. Only in the method of circuit closure. Alternating current and direct current, which is constantly repeated, and not with the usual closing and opening, but with a smooth rise and fall, so the rotor rushes and runs to the zone of exposure.
The nature of electricity is the same and this conditional division is made by the cause of not correct understanding and explanation of this phenomenon or property of matter.

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