Theory of Electronics

What is Current ?

As we study from the very lower classes that, the flow of charges in an electric conductor is called as Electric current.

It can have analogy if we say : the flow of water in a channel is called river.

Now the question arises, what is a charge ?

Charge is a physical property of the matter due to which it experiences either force of attraction or repulsion when brought near to another matter bearing opposite charge or same charge respectively.

Now we also know that smallest particles of which matter constitutes are named as :

• Protons( they bear a +ve charge)
• Electrons(they bear -ve charge) 
• Neutrons(they bear no net charge)

So, when we say that current is flowing in a conductor, we actually mean, the charged particles are moving in  that conductor. One more thing to add here is that only conductors have plenty of free charged particles due to which they are able to move, that is why they are known as good conductors of heat and electricity.

On the other side, Insulators are bad conductors of heat and electricity, because they do not have sufficient charged particles(i.e. electrons and protons)