Electric Fields and Potentials. 1.1 Electric field strength and Coulomb's law. Charges and lines of electric field. Positive charges are sources of , negative charges are sinks of .
Electric fields exert force on electric charges.
We can trace the direction of the electric field throughout space by plotting lines of electric field. At any point, the electric field line indicates the direction of the electric field and hence the direction of the electric force on a positive charge . The spacing of the field lines is a measure of the strength of the electric field. The electric field due to a static electric charge is known as the electrostatic field. The electric field due to a positive charge is thus directed radially outwards from the charge.