Understanding Alternating Current Supply in Households

[kiamzattu]

My Question is this-

We get AC supply to our houses, So for the first half cycle the current should from thro
the live wire to the load and then return thro neutral, Now for the 2nd half cycle this
must be reveresed, That is Neutral-load-Phase. This is wat is Alternating current.
But I closed the switch, inserted the tester in the live terminal and it glowed, jus as
expected,then i inserted the tester into the neutral and it didn't glow.How's that?
Now if the neutral wire acts only as the return wire and v get current only thro the
phase terminal from the generating stations how can v cal that as alternating current, becaus
the current is uni-directional.


Regards
Anand

 

[Shooting Star]

The potential of the live wire cycles from positive to negative. When a simple appliance, a light bulb say, is connected between the live and the neutral, the direction of the current also changes from positive to negative cyclically across the load. So, it's not unidirectional, but only the potential of the live wire is changing periodically. The neutral wire remains at a constant (zero) potential.

 

[sir-pinski]

Hi Anand,

Thank you for your question about alternating current supply in households. To answer your question, we first need to understand the basics of how AC electricity works.

Alternating current, or AC, is a type of electricity that constantly changes direction. This means that the flow of electricity is constantly reversing, going back and forth between the live wire (also known as the "hot" wire) and the neutral wire. This constant back-and-forth movement is what gives AC its name.

In your example, you are correct that during the first half cycle, the current flows from the live wire to the load and then returns through the neutral wire. However, during the second half cycle, the current does not reverse and flow from the neutral wire to the load. Instead, the live wire remains the source of the current and the neutral wire acts as the return path for the current to complete the circuit.

This may seem confusing, but it is important to remember that the direction of the current is constantly changing in an AC circuit. So while the current may appear to only flow in one direction at a given moment, it is actually reversing direction very quickly.

Now, to address your question about the tester not glowing when inserted into the neutral wire. This is because the tester is designed to detect the presence of voltage, not the direction of the current flow. In an AC circuit, there is always voltage present in both the live and neutral wires, but the direction of the current flow is constantly changing. So when you insert the tester into the neutral wire, it does not glow because the current is not flowing in that direction at that moment.

In summary, alternating current is defined by the constant back-and-forth movement of the current, not by the direction of the current flow at any given moment. I hope this helps to clarify your understanding of AC supply in households. Please let me know if you have any further questions.

Best regards,