Charles Augustin Coulomb June 14, 1736 - August 23, 1806. Was a French Physicist.
Coulomb created a device known as a torsion balance which could accurately calculate the force exerted between point charges. This force was explained as such: "The force exerted between two point charges is equal to the product of their strength and inversely proportional to the square of the distance between them". This statement/law is known as Coulomb's Law or The Inverse Square Law.
As a formula this becomes:F = (Q1 * Q2)/(r2)
In vaccum or free space this formula is adapted to include the constant of proportionality which is 1/4π. Also in free space the permittivity of free space is equal to 1/36π x 10-9(given the greek letter ε (epsilon) o = εo), the fromula becomes.
F = (Q1 * Q2)/4π εo r2
Although a useful concept it would be beneficial to know the strength the force exerted on the other charge, known as the electric field strength/intensity. To do this one charge is fixed say Q1 and the other Q2 is allowed to move. To calculate the force per unit charge or rather force per Q2 we divide the formula for Coulomb's Law by Q2, giving a new vector E which is;
E = Q1/4πεor2
We now have a way of determining the strength of an electric field, or the force field of one (fixed) charge acting on another (moveable) charge.
Remembering that the electric field strength is defined as a moveable point charge in the vicinity another fixed charge of the same polarity. An analogy to describe the Force (F) and Electric Field Strength (E) would be to use two magnets;
Take two magnets each with its own North and South Poles (Naturally), now if we move the two magnets towards each other(the direction of the poles e.g. whether north or south are facing each other, is irrelavent) a force is experineced whether it be a force of attraction or repulsion. The force F is that force exerted between the two magnets.
If we now fix the position of one magnet but allow the other to be brought nearer to the other fixed magnet, then what we would notice is that the force which is experienced is that force which the fixed magnet has on the moveable one. Meaning we can now measure the electric field strength of the fixed magnet by noticing how strong the force of attraction or repulsion is on the moveable magnet.
NOTE: The writing package won't allow me to use the power notation, particularly power of 2, so in the above formulae please take the number 2 after a letter/variable to mean square, as in algebra numbers come before variables anyway, thank you)
Nirvana.
Coulomb created a device known as a torsion balance which could accurately calculate the force exerted between point charges. This force was explained as such: "The force exerted between two point charges is equal to the product of their strength and inversely proportional to the square of the distance between them". This statement/law is known as Coulomb's Law or The Inverse Square Law.
As a formula this becomes:F = (Q1 * Q2)/(r2)
In vaccum or free space this formula is adapted to include the constant of proportionality which is 1/4π. Also in free space the permittivity of free space is equal to 1/36π x 10-9(given the greek letter ε (epsilon) o = εo), the fromula becomes.
F = (Q1 * Q2)/4π εo r2
Although a useful concept it would be beneficial to know the strength the force exerted on the other charge, known as the electric field strength/intensity. To do this one charge is fixed say Q1 and the other Q2 is allowed to move. To calculate the force per unit charge or rather force per Q2 we divide the formula for Coulomb's Law by Q2, giving a new vector E which is;
E = Q1/4πεor2
We now have a way of determining the strength of an electric field, or the force field of one (fixed) charge acting on another (moveable) charge.
Remembering that the electric field strength is defined as a moveable point charge in the vicinity another fixed charge of the same polarity. An analogy to describe the Force (F) and Electric Field Strength (E) would be to use two magnets;
Take two magnets each with its own North and South Poles (Naturally), now if we move the two magnets towards each other(the direction of the poles e.g. whether north or south are facing each other, is irrelavent) a force is experineced whether it be a force of attraction or repulsion. The force F is that force exerted between the two magnets.
If we now fix the position of one magnet but allow the other to be brought nearer to the other fixed magnet, then what we would notice is that the force which is experienced is that force which the fixed magnet has on the moveable one. Meaning we can now measure the electric field strength of the fixed magnet by noticing how strong the force of attraction or repulsion is on the moveable magnet.
NOTE: The writing package won't allow me to use the power notation, particularly power of 2, so in the above formulae please take the number 2 after a letter/variable to mean square, as in algebra numbers come before variables anyway, thank you)
Nirvana.