What is the Difference Between AC and DC

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What is Current.

First off, what is current. Current is expressed in a unit called Amps. Amps are a measurement of how many electrons pass per second. That is to say, a wire with 40 coulombs passing any point in a 2 seconds would be said to have 20 Amps of current (40 Coulombs (a unit of charge given as 6.24x1018 electrons) / time in seconds or in this case, 2 seconds. The Amp is also known as Coulombs per second) Another trick about current is that it is measured in the movement of the positive charge. Literally that is to say the current moves in oppostion to the electrons. This is because originally it was thought that the positive charge is what moved, both are viable, but in reality a positive charge is generally fixed since within an atom the electrons are migratory, while the protons and neutrons tend to be stationary.

What is AC/DC?

AC and DC literally stand for Alternating Current and Direct Current. Direct Current is very convenient and is used in many modern day utilities. For a circuit with DC the current is constanly in one direction, while the voltage remains constant. This makes for a simplistic circuit, for example a flashlight, The batteries are a source of electrochemical DC power and . However AC is called Alternating Current because the voltage changes from negative to positive a given number of times a second, this is also described as the frequency of the power. An example of this would be a motor ran by a hand crank. The inversing of charges creates a sinusoidal graph which looks something like figure 1 (given in radians). This makes for an unsteady power source and can often times be warped from the sinusoidal shape. So the main difference between AC and DC is the way the energy is transmitted.

Why are we using Alternationg Current today? There are a few reason although mainly it was due to the technology of the late 1800's and early 1900's. Nikola Tesla being one of the leading scientists for Alternating Current, created a way to run engines and also convert AC Volts and Amps. He came up with this while he was supposedly in a park in Budhapest. He sat down and drew out the basic diagram of a motor run by a magnetic flux.

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