An introduction to BASIC ELECTRICITY by R.Hariharakrishnan
An introduction to
BASIC ELECTRICITY
AUTHOR
R.HARIHARAKRISHNAN,
POSTMASTER
SRIVAIKUNTAM HPO 628601
THIS ARTICLE IS DEDICATED TO MY PARENTS WITHOUT WHOM AM JUST BLACK AND WHITE
I AM INDEBTED TO
SRI.M.VENKATESAN, DSM, SRIVAIKUNTAM HPO
SMT.E.PACKIYALAKSHMI, PA, SRIVAIKUNTAM HPO
SMT.G.JANAKI, PA, SRIVAIKUNTAM HPO
FOR THEIR
ENCOURAGEMENT IN WRITING THIS ARTICLE.
Basic Electricity
As you may aware, in this world, everything is made up of atoms, the smallest particle. Dalton is the first to propose an atomic theory. As per his theory, the atom is the smallest particle which cannot be divided further.
Scientists like J.J.Thompson, Rutherford, James Chandwick proved that an atom can be further divided into particles. Hence the name proton, electron and neutron. Every atom is made up of these 3 particles. Further particles which are called sub atomic particles are also found, which is out of scope for the present topic. For the time being, it is enough that all things are made up of atoms and each atom is made up of electrons, neutrons and protons. It is worth to note here that J.J.Thompson was a Nobel Prize winner and it is more important that 7 of his research students had won the Nobel Prize! Also, he was the chair-person of Royal Society which conferred FRCS to Srinivasa Ramajujan, the gifted mathematician from India.
Thales of Greek observed that when amber rubbed attracted tiny pieces of straw. This is named as “electricity”. Charles Augustus Coulomb better known as Coulomb with some scientists observed that some materials like glass, sealing wax and ebony acquired the property of attracting things. They named them as “electric charge”. They also found that there are two types of charges, “positive” and “negative”. The names “positive” and “negative” are contributed by Benjamin Franklin. It may be added that, he invented the lightning arrester. Also he was the Postmaster General of US postal department. When a glass rod is rubbed with silk cloth, it acquired a positive electric charge. On the other hand when an ebonite rod is rubbed with fur a negative charge is developed.
The lightning conductor is working on the principle of these charges. We might have seen that a tall metal rod with some spikes is placed on the top of tall buildings. This is called the lightning conductor. This prevents the building from damage due to lightning. The lightning conductor was devised by Benjamin Franklin.
It is a long copper rod placed at the top of the building. This rod passes through the building to the ground. The bottom of the rod is connected to a copper plate which is buried deeply in the ground. At the top of the copper rod, a number of spikes are connected.
When there is lightning, the air makes the clouds negatively charged. The cloud passes through the building. Due to this negative charges, the tip of the spikes are induced with positive charges. (Action of point charges). These positive charges neutralize most of the negative charges of the cloud. If at all some negative charges of the cloud are attracted by the spikes, they will travel to the ground and passes through the earth and hence the building is prevented from damage due to lightning.
→
0 comments:
Post a Comment