Changes

In [[International_System_of_Units|SI units]] the charges are measured in [[International_System_of_Units#Coulomb|Coulombs]], the force in [[International_System_of_Units#Newton|Newtons]], the distance in [[International_System_of_Units#Meter|Meters]], and the value of <math>\epsilon</math> is <math>8.854 \times 10^{-12}</math> Coulombs² per Newton meter², or [[International_System_of_Units#Farad|Farads]] per meter.

In [[International_System_of_Units|SI units]] the charges are measured in [[International_System_of_Units#Coulomb|Coulombs]], the force in [[International_System_of_Units#Newton|Newtons]], the distance in [[International_System_of_Units#Meter|Meters]], and the value of <math>\epsilon</math> is <math>8.854 \times 10^{-12}</math> Coulombs² per Newton meter², or [[International_System_of_Units#Farad|Farads]] per meter.

Michael Faraday reformulated the electric and magnetic forces in terms of ''fields''  He said that what was really happening was that each charge was creating and electric field (called E) that acted on the other charge.  The field created by the charge q₁, as observed at distance d, is

Michael Faraday reformulated the electric and magnetic forces in terms of ''fields''  He said that what was really happening was that each charge was creating an electric field (called E) that acted on the other charge.  The field created by the charge q₁, as observed at distance d, is

:<math>E = \frac{q_1}{4 \pi \epsilon\ d^2}</math>

:<math>E = \frac{q_1}{4 \pi \epsilon\ d^2}</math>

and points directly outward from that charge, in all directions.  The force felt by charge q₂ is

and points directly outward from that charge, in all directions.  The force felt by charge q₂ is