It is a region of space where a test charge is subject to the action of a force of electrical origin.
It is said that an electric charge generates an electric field. The field intensifies as we approach this charge and will weaken as we move away from it. Therefore, the electric field \(\vec{E}\) is a function of the distance \(d\) between the charge and a point in space. $$\vec{E}=\vec{E}(d)$$ To calculate the electric force due to the electric field of a charge, we can use a test charge \(q_0\). Suppose \(d_0\) is the distance from the charge to the test charge, the force on the test charge, due to the field-generating charge, is: $$\vec{F} = q_0 \vec{E}(d_0).$$ The electric field unit in the \(IS\) is Newton per Coulomb \([E]=\frac{N}{C}\) .
To facilitate the understanding of the electric field, we imagine "field lines".
The script for the construction of these lines is: