Functioning of AC current in simple terms?

In summary, in AC circuits, the electrons move back and forth as a whole, including within the load device, at a very slow speed. The energy flow from the power supply to the appliance is carried by an electromagnetic wave and is much faster than the movement of the electrons. This can be compared to the flow of water in a pipe, where turning on a tap causes an immediate effect even though the water from the source takes time to reach the tap. In AC circuits, the electrons change direction every few milliseconds but their mean position does not alter, allowing for the flow of energy to power devices.
  • #1
lukeskywalker
3
0
Hi,

Thank you for reading this.

I understand the functioning of DC current. You create a potential difference and the electrons flow from the power source through the electrical appliance (thereby, powering it) and flows back, completing the circuit.

But, in AC, the electrons, according to what i read, move in one direction for sometime and then switch direction. And i read somewhere that there is no net movement.

How does this work? I mean the electrons have to flow in one direction for them to reach the appliance, right? If they move forward and backward, how does it reach the destination?

Please explain in simple terms.

PS: I understand that my questions and my understanding of electricity may seem childish to people who know more than me.
 
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  • #2
Electrons move throughout the conductor when you complete the circuit, not just from the power source. Imagine the water pipes in your house. When you first turn on your hot water faucet, the water in the pipe nearest to the faucet comes out first, which is why it takes time for the water to warm up. You have to get that cold water that's been sitting there out first.

In an AC circuit the electrons in the circuit move back and forth as a whole, including within the load device (the appliance).
 
  • #3
Electrons in a wire flow incredibly slowly (an average speed of about 1mm per second) The energy flow from the Power Supply to the appliance is not at that speed. It is at a little less than the speed of light and is carried by an Electromagnetis Wave. (Think of the links of a cycle chain, which do not need to travel from pedal to back wheel before the bike starts moving.)

A lamp may be lit and go off well before any of the electrons in the battery have actually got to the filament via the switch. Drakkith's hot water system explanation is an excellent one*** (although the water model is usually a risky one); the effect of turning on the tap is instant and long before the water from the source actually gets to the nozzle of the tap.

With AC, the electrons in the wire change direction every few milliseconds and their mean position does not alter. You would never get any hot water from the system if you used and AC hot water supply but you could drive a hydraulic machine with pull push (AC) water supply pressure.

***Amazing that I have never come across that particular argument. It's a really good one amongst many really dodgy 'water' arguments.
 

FAQ: Functioning of AC current in simple terms?

What is AC current and how does it work?

AC (alternating current) is a type of electrical current that periodically reverses direction. This is typically used to power household appliances and electronics. AC current is generated by a power source, such as a generator, and then distributed through power lines to homes and buildings. The current alternates between positive and negative charges, which is why it is called alternating current.

What is the difference between AC and DC current?

The main difference between AC and DC (direct current) is the direction of the flow of electrons. In AC current, the flow of electrons alternates between positive and negative, while in DC current, the flow is always in one direction. Additionally, AC current is typically used for long-distance power transmission, while DC is used for smaller devices and electronics.

How does an AC circuit work?

An AC circuit consists of a power source, such as a generator, and various components such as resistors, capacitors, and inductors. The power source produces an alternating current, which flows through the circuit and powers the connected devices. The components in the circuit control the flow of current and can change its properties, such as voltage and frequency.

What is the frequency of AC current?

The frequency of AC current is the number of times the current alternates direction per second. In the United States, the standard frequency for household electricity is 60 Hz, meaning the current alternates direction 60 times in one second. In Europe and many other countries, the standard frequency is 50 Hz.

What are the advantages of using AC current?

AC current has several advantages over DC current. It is easier to change the voltage and transmit over long distances, making it more efficient for power transmission. Additionally, AC current can be easily converted to different voltages, making it suitable for a variety of devices and appliances. AC current is also safer to use as it can be easily controlled and switched off in case of emergencies.

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