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Q & A: How practically the GROUNDING is done?

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Most recent answer: 01/12/2015
Q:
How practically the GROUNDING is done in any electronic or electrical circuits?
- rohit (age 20)
new delhi,delhi,india
A:

The charges are distributed on a conductor body in such a way to keep the potential everywhere the same. And the amount of charge at each part of the conductor is roughly proportional to its size (You can assume both your circuitry and a big charge sink as spheres, if you would like.). So, if you want to get rid of the charges on a particular piece of circuitry, you need to connect it to a big object. In practice, one makes use of the biggest object available on Earth: the Earth itself. The electrical outlets on the walls have a third wire that goes to a piece of metal buried to the soil somewhere nearby, which completes the connection to a very big sphere! So this is why there are no charges are left on that part of your circuitry.

Now if you are wondering how grounding prevents electric shocks, this is a bit different. If there is a malfunction in somepart, say a cable gets loose and touches the metal body of a washing machine, than the equipment becomes a hot wire. When you touch it, a significant current will flow through your body. If however, the equipment is grounded, the grounding wire will constitute a path with a quite low resistance, and hence it will bring the objects potential effectively to zero, which is what your feet are also at. So a negligible amount of current will pass through your body!

Tunc


(published on 01/12/2015)

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