# What Is Electric Charge

• We know that an atom consists of electrons, protons, and neutrons.
• Each electron has a negative charge and each proton has a positive charge.
• a neutron carries no charge and is therefore neutral.
• In an atom, the number of electrons is equal to the number of protons and the atom is electrically neutral.
• electrons may be added to or taken away from an atom.
• this disturbs the electrical balance of the atom.
• If an atom loses an electron it is left with an overall positive charge since it has a proton in excess of those needed to balance the effect of its electrons.
• such a charged atom is called a positive ion.
• If an electron is added to an atom, it attains a negative charge. Such a charged atom is called a negative ion. A body having a number of ionized atoms is said to be electrically charged.
• The SI unit of charge is the coulomb [C]
• the measure of charge moved by one ampĂ¨re of current in one moment of time [A s].
• The thinking behind this definition is best left to later sections in this book.
• an uncommonly enormous unit for everyday applications.

## Elementary Charge

• 1.60 × 10−19 coulombs
• the size of the charge on an electron or proton
• A charge is quantized in products of the basic charge.

## Conservation of Charge

• The complete charge of a shut framework is steady.
• The universe is a shut framework.
• At the point when subatomic particles are made, they don't include or subtract charge from the universe in general.

### Limitations of Terzaghi Theory

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### Price Guard Wire Method

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### Streamer Theory of Breakdown in Gases

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