The electric field (E) is derived in the same way from the equation 
(see right)
where:
(constant), - Q = electric force of one object (C),
- q = electric force of the other object (C), and
- d = distance between the two objects (m).
However, electric field E is a little bit different from gravitational field g. Gravitational force depends on mass, whereas electric force does not depend on mass. Instead, electric force depends on charges on both objects.
By rearranging the formula, we get:
- Electric field (E) for Q:
- Electric field for q:
Let’s divide the electric force (F) by charge q: 
Therefore, the electric field tells us the force per unit charge. 
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