What is Current?

What is Current?

An atom is a building block of matter that cannot be broken apart using any chemical means. Nuclear reactions can alter atoms.

There are three parts of the atom 

1. protons (positively charged)
2. neutrons (neutral charge)
3. electrons (negatively charged)

Protons and neutrons form the atomic nucleus. Electrons are attracted to the protons in the nucleus, but are moving so quickly they fall toward it (orbit) rather than stick to protons.

With some types of materials, such as metals, the outermost electrons in the atoms are so loosely bound that they chaotically move in the space between the atoms of that material by nothing more than the influence of room-temperature heat energy. they are often called free electrons and these type of materials are called Conductors

In other types of materials such as glass, the atoms’ electrons have very little freedom to move around. They are called insulator

Here are a few common examples of conductors and insulators:

Conductors copper gold graphite dirty water

Insulators glass rubber oil pure water

Definition Of Current

The flow of electrons from one atom to another atom is known as current and is designated with the symbol ‘I ‘.

and Unit of Current is Ampere

The amount of current flowing is determined by a number of electrons that pass through a cross-section of the conductor in one second. 

Due to a very small size of atoms, it takes about 10^24 electrons to fill one cubic centimeter of a copper conductor. Trying to represent the small value of current in terms of electrons would be very difficult. That is why current is represented as Ampere.

Meaning of 1A Current

A current of one-ampere means, in one second 6.24 X 10^18 electrons move through a cross-section of a conductor.

Here is great Video by Sparkfun on Current