How Does Alternating Current Work?

In summary, the conversation discusses the concept of alternating current and how it differs from direct current. The analogy of beads on a wire is used to explain the back-and-forth motion of electric charge in an alternating current circuit. It is also mentioned that while direct current is unidirectional, it does not mean that electrons physically travel from the source to the device.
  • #1
ronaldoshaky
55
0
Hello

I read on Wikipedia that alternating current periodically changes direction. So if it keeps going backwards and then forwards how does the charge get around the circuit?

Thanks
 
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  • #2
Think of beads on a wire, filling the wire like a pearl necklace. Suppose the wire forms a loop a meter in diameter.

Push a bead forward 3 cm. Pull it back 3 cm. Repeat. Your finger is the motive force. Have someone else watch, somewhere on the far side of the loop: he is the amp meter. Will he report beads moving? Yes, back and forth, at whatever velocity.

--John
 
  • #3
I would like to add something to your example JD, something that maybe even the initial poster knows already but I find that I should point out.

Direct current is unidirectional move of electric charge, but that doesn't mean that electrons travel from the switch to the electric device in order to power it. I think of the current as the "order" that is given to the wire by the generator for all free electrons along the wire to start moving, to one direction when it comes to direct current and back-forth when it comes to alternating current.

I hope I've helped.
 

1. How does alternating current (AC) differ from direct current (DC)?

AC is a type of electrical current where the direction of flow of electrons periodically reverses, while DC is a type of electrical current where the flow of electrons is in one direction. AC is used for long distance power transmission, while DC is commonly used for electronic devices.

2. How is AC generated?

AC is generated through the use of an alternating current generator, which uses a magnetic field and rotating coils to produce a changing current. This current then flows through power lines and can be transformed to different voltages for various uses.

3. What is the frequency of AC?

The frequency of AC refers to the number of complete cycles of alternating current per second. In the United States, the standard frequency is 60 Hz, while in other parts of the world it may be 50 Hz.

4. How does AC allow for power transmission over long distances?

AC is able to travel long distances with minimal energy loss due to its ability to be easily transformed to different voltages. This allows for the use of high voltage transmission lines, which reduces the amount of energy lost during transmission.

5. Can AC be converted to DC?

Yes, AC can be converted to DC through the use of a device called a rectifier. This device uses diodes to convert the alternating current to direct current by allowing the flow of electrons in only one direction.

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