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Electricity field intensity within a conductor is always zero.Why?

Electricity field intensity within a conductor is always zero.Why?

Asked Shaji

Answer:

The main difference between a conductor and an insulator is that the conductors contain plenty of free electrons which are free to move throughout the conductor; whereas the insulators do not have free electrons at room temperature.

When a conductor is held in an electric field, the free electrons inside them instantly drift opposite to the direction of electric field until the electric field due to the drift balances the external electric field and the net electric field inside the conductor becomes zero.

 

Current Carriers and conduction

1. Do the protons flow when current flow?
2. In case of semiconductor do the holes flow?

Animesh asked

Answer:

Atom 3D Model

In metallic conductors, free electrons are the current carriers, i.e, it is due to the motion of the free electrons that conduction takes place in a metallic conductor. The protons do not move as they are inside the nucleus and bound by strong nuclear forces. It is the electrons of the outermost shell of the atom which are least bound to the atom, flow and cause conduction

In semiconductors the current carriers are free electrons and holes.

What are holes?

Holes are actually vacancies created when an electron is freed from a bond. It is assigned a positive charge. When a potential difference is applied across a semiconductor, the free electrons move towards the positive terminal as in the case of a metal. The bonded electrons also move towards positive terminal from vacancy to vacancy and this causes the holes  t move towards the negative terminal.

 

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