Answer :
Answer:
[tex]E=\frac{k\,Q}{d^2}[/tex]
Explanation:
The electric field E is derived from the electric Coulomb Force ([tex]F_C[/tex]) between two charges located at a distance "d" from each other, by using positive test charge in the following expression:
tex]E=\frac{F_C}{q}[/tex]
and where the Coulomb force between a charge Q and another one q (the test charge) is giving by:
[tex]F_C=k\frac{Q\,q}{d^2}[/tex] where K represents the Coulomb constant.
Since the field is the force per unit charge using a positive test charge, the field's units will be in units of Newtons/Coulomb, and the formula for the field would be modified so as only one charge (Q - the one producing the field) will appear in the numerator:
The strength of an electric field E produced by a single charge Q at a distance d from it is therefore given by the formula: [tex]E=\frac{k\,Q}{d^2}[/tex].