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I am having some trouble with the concept of grounding the electric supply.

The doubt is basically : if I hold a live wire standing on the ground, why do I get a shock?.

Please don't say there exist a potential difference. . . Because I think potential difference is not enough... The neutral and ground wires are connected near the meter box and the ground rod is buried there. There is nearly 10-20 meters of non-conducting ground (bricks, stones and mud) between me and that point. So even if I close the circuit, there is a high resistance for current flow.

Now given the fact that we will get a shock if we do that, it seems that the ground beneath me is actually at the same potential as the ground to which the neutral was connected. So that means earth has the same potential everywhere (since it doesn't matter where I stand). But then...

If I take a normal battery and Bury its negative terminal in actual ground and connect a bulb between $+$ and actual ground, It should glow... because of the same reason why I get shock. But it does not happen.

I think I've done a poor job phrasing the question but I hope everyone understands.

Also a related question : If i plug in one terminal of a bulb into live and connect the other to my floor, will the bulb glow? PS : I tried it doesn't glow. So why is it that if I am between live and ground I get shock whereas a bulb does not?

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Disclaimer: electricity is extremely dangerous. Please don't play around with your home's main electricity. You could badly injure or even kill yourself. This is especially the case if you live in a country that uses $220~\rm V$ or higher.

There are a lot of things that can factor into you receiving an electric shock or not. But the general idea is that you are roughly at the same potential as ground normally. When you come into contact with a live wire, there is a potential difference and some current flows, at least momentarily. The human body can perceive fairly small currents of $\sim 500~\rm\mu A$, so the current doesn't need to be large for you to feel a shock.

That doesn't mean the current will be anywhere near large enough to light up a bulb. The current required to light an incandescent bulb is much, much larger, and would likely kill a human.

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