Name : Charles Agustin de Coulomb Nationality: French Born: June 14, 1736 Died: August 23, 1806 Works: Coulombs law Law of electrical repulsion Inverse torsion law Invented a sensitive instrument to measure the electrical forces involved
Frenchman born on June 14, 1736 He attended Mazarin College in Paris before his father’s poor business decisions strained the family’s finances resulting in Coulomb’s relocation to Montpelier Coulomb joined the Academy of Sciences there and presented several papers to the organization topics in astronomy and mathematics
Hoped to gain entry into the Royal School of Engineering Decided to return to Paris for a short time, where he would have access to the better tutoring 1760 he began his formal studies at the institution completing them less than two years later
After graduation, he embarked on a long career within the Military Engineering Corps. In the army as a military engineer, he was drafted to the island of Martinique, in the West Indies His duties forced him to make several moves over the subsequent decades.
in the West Indies, he took part in the erection of Fort Bourbon. But the climate was then fatal; most of his comrades died of fever, and Coulomb, after a stay of three years, returned home with his health permanently injured.
He submitted his first treatise to the Academy of Sciences in Paris in 1773 many more would follow on topics ranging from mathematical solutions of engineering problems to studies of friction, elasticity, electricity and magnetism. In 1777 Coulomb was awarded part of the Academy’s grand prize for a paper discussing the magnetic compass In 1781 he was sole recipient of the prize for a groundbreaking examination of friction.
In 1784 he presented a paper to the Academy on the elasticity of wires under a twisting stress he observed that a very feeble force was sufficient to twist a long thin wire through a large angle This led to the invention of his well-known torsion balance
It consists of a ‘ needle’ suspended by a fine wire, and screened from currents of air by a glass cover. When the needle is deflected from its zero position through a certain angle by a disturbing force, it can be brought back to zero against the force by counter twisting the suspension wire
and the torsion of the wire becomes a measure of the disturbing force. To this end a graduated scale is added, to indicate the turns of the counter-twist. The rate of oscillation of the needle when deflected is also a means of calculating the disturbing force.
By presenting electrified bodies to the needle, which could itself be electrified, Coulomb discovered that the force of attraction or repulsion between two quantities of electricity was directly proportional to the quantities, and inversely proportional to the square of the distance between them
Similar to Isaac Newton’s inverse square law of gravitational force, Coulomb’s law states that the electric force between charged objects inversely depends upon the distance between the objects. That is the electric force decreases with the square of the distance between them.
gravitation is influenced by the mass of the objects Coulomb’s law depends upon the charge of the objects involved. When the objects in question are both positively or both negatively charged, the forces between them are repulsive but attractive forces arise between objects carrying opposing charges.
upon returning to Paris, became one of the first members of the newly formed French National Institute His health grew progressively worse leading to his death on August 23, 1806. He was honored by the adoption of an SI unit of electric charge bearing his name. The coulomb (C) is equivalent to the charge transferred by a current of 1 ampere in 1 second.