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# 1 Coulomb Equals

Coulomb is a basic unit of electrical charge and also coulomb is the SI unit of electric charge. Its unit symbol is ‘C’.

1 – coulomb – equals the charge of 6.241 × 1018 electrons approximately.
Also 1 – coulomb – equals the product of one ampere in one sec. We can also say that 1 – coulomb – equals the amounts of excessive charge that is on the positive side of a capacitor of a farad that is charged to a potential difference of a volt.
It was named after the scientist Charles–Augustin de Coulomb.

Generally the coulomb is defined in amperes and seconds: 1 C = 1 A × 1 s. Seconds can be defined as the frequency that is emitted by the caesium atoms naturally and the ampere can be defined with the use of Ampere’s force law. Practically, we use the watt balance for measuring amperes that too with the maximum accuracy level possible.

Now, the charge of an electron is about 1.60217657 × 10-19 coulombs. So by taking the reciprocal of the same also, 1 – coulomb – equals or can be considered to be 6.241509324 × 1018 electrons or protons.

Below are given some of the conversions:
• The Faraday unit of charge is the value of the electrical charge of one mole and the value of one Faraday is 96485.3399 coulombs.
• The value of 1 ampere hour is 3600 coulombs.
• The basic charge is equal to 1.602176487 × 10-19 coulombs.
• The value of obsolete electrostatic charge unit in CGS is 3.3356 × 10-10 coulombs approximately. This is one third of a nano-coulomb.
• The magnitude of the electrical charge in 6.24150965 (16) × 1018 protons or electrons is the value of one coulomb.
Various examples of coulomb charge in daily life are stated below:
• The charges in the static electricity generated from rubbing of the materials together with each other of measure of a few micro-coulombs.
• The measure of charge that is travelling through a lightning bolt is somewhere around 15 coulombs. It is also a fact that large bolts can be of measure up to 350 coulombs.
• The amount of the charge which is travelling through a normal alkaline battery of AA standard is near to 5 kC which is equal to 5000 coulombs that is nearly equal to 1.4 A-h. After this much charge has been flowed, wither the battery should be discarded or it should be recharged.
• The Coulomb’s law states that, when two negative point of charges of 1 coulomb each are placed one meter apart, a repulsive force of 9 × 109 N is experienced.
• The hydraulic analogy equates the charge to a given volume of the water and the voltage to the pressure. The measure of one coulomb is the value of negative charge of 6.24 × 1018 electrons. The energy amount that is transferring in the flow of one coulomb might vary. This can be seen by the comparison here: in comparison to a dry cell battery, 300 times lesser electrons flow through a lightning bolt while the total energy that is transferring with the flow of the electrons in a lightning is greater 300 million times.

Question:

Answers:Well its an experimentally found value of that constant , which gave all the correct results....

Question:I understand the mathematical formula of coulomb's law but i'm trying to grasp what the coulomb is exactly. I know it is the measure of charge but my textbook is saying that 1 Coulomb is a large force and 1 coulomb is equal to the charge of 1 * 10^19 electrons ect. But aren't 10^19electrons charged commonly seen like i'm sure a charged penny has 10^19 charged electrons. or a charged peace of clothing has 10^19 electrons or more. I'm assuming coulomb measurements are small because only a small amount of those particles are charged? Anyone have an easy explanation i'm confused? This is for my own knowledge and curiosity.

Answers:It's always refreshing and rewarding to try to answer a question asked out of curiosity and wanting to get to know things. From what You wrote, I assume You're asking Yourself if all of the electrons are actually charged. All electrons are charged in exactly the same way, i.e. they carry what is known as "elementary charge" of 1.602 10^-19 C. Every electron carries this charge and it cannot change. How much an object is charged is due to excess electrons, compared to other charged particles, namely positively charged protons in atomic nuclei. Since matter is made of atoms, which contain protons in their nuclei and electrons in their orbits, an atom is generally neutral although it can contain many protons and electrons. But if a piece of material contains excess electrons, it will have a net negative charge. How much is this charge? If an object has 10 electrons more than protons, the excess charge will be 10*(1.602 10^-19 C). All the remaining electrons and protons cancel each other out in their charge, so You don't see the effect on a macroscopic object. If it has more electrons, You'll see the negative charge exerting force on other nearby charged objects, and if it has a lack of electrons (less electrons than protons), the object will have a net positive charge. Depending on how much electrons You remove or add, You'll create a more or less charged object. If You add circa 10^19 electrons, the object will become charged by approx. 1 coulomb of charge. So, a "coulomb" can be thought of as a measure of how many excess or lacking electrons are there in a macroscopic object, the electrons being "charge carriers". And the more electrons You want removed (or added), i.e. the more You want to charge an object, the more powerful generator You need for this, to act against the attractive forces that act between protons and electrons, trying to keep them together. To remove the first electron, Your generator needs to act against the Coulomb force of only one remaining excess proton in the object; after You've removed 10^6 electrons, when removing the next electron, Your generator needs to work against the force of 10^6 excess protons that remained, which exert a larger force on that electron. How much force? - that can be calculated from Coulomb's law.

Question:A charge of -3.2E-8 Coulombs consists of how many electrons? I know that the charge on an electron is -1.6E-19 Coulombs, but I don't understand how to find out how many electrons it equals.

Answers:Remember stoichiometry from chemistry? Set it up just like that. Mathematically, you divide -3.2E-8/-1.6E-19. -3.2E-8 c X (1 electron/ -1.6E-19 c)

Question:just wanted to know but I can't even what a Coulomb is a measurement of.

Answers:Thumbs down to GTB, not for giving a wrong answer, but for plagarism. If you kind of combine what everybody else said, then you will see that you have not included enough facts in your question. You can't "produce" a Coulomb, but you can move one Coulomb of electric charge from point A to point B. The amount of energy required to do that (Joules) is numerically equal to the potential difference (Volts) between point A and B *IF* the voltage is constant. It's more complicated than that if the problem is to move one Coulomb of charge between two finite, electrically isolated conductors (e.g., between two metal spheres) because in that case, the Voltage is not constant.