# How the plug works in both in both directions in socket?

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1. Nov 12, 2015

### 123kid

If I plug my electrical device in the socket in any direction the device works. If i plug the device in opposite direction, it makes no problem. while the current in the socket is coming in hot wire.
Is there hot and neutral also in the wire connected to the device or they are both hot ?

2. Nov 12, 2015

### Staff: Mentor

3. Nov 12, 2015

### jbriggs444

It is alternating current. Part of the time the "hot" wire is pushing current into the circuit and that current is sinking into the neutral wire. Then a fraction of a second later the hot wire is pulling current and the neutral is sourcing it. It does not matter which wire is "hot" and which wire is "neutral". All that matters is the potential difference between the two. That difference is the same regardless of which way you plug in.

4. Nov 12, 2015

### Michael V

Hi there,

Its because the current alternates back and forth between poles, look up some DC vs AC theory.

Hope that gets you going the right direction.

5. Nov 12, 2015

### 123kid

But when i check the socket with tester, it just shows the current in one hole. ( This AC current my greatest confusion these days )

6. Nov 12, 2015

### jbriggs444

Your tester does not detect current. It detects voltage.

7. Nov 12, 2015

### 123kid

ok .. thank you.

8. Nov 12, 2015

### Staff: Mentor

Note that having a polarized 2-prong plug has at least two important functions:

-1- As mentioned in the Hyperphysics link, it lets you be sure that the power switch for the device is in the Hot lead.

-2- For lamps like the one below, the more exposed threads part of the bulb socket is connected to the Neutral line, and only the small button down in the bottom of the bulb socket is connected to Hot. That makes light fixtures much less of a shock hazard...

https://softsolder.files.wordpress.com/2012/09/img_2327-interior-of-3-way-lamp-socket.jpg

Last edited: Nov 12, 2015