In textbooks the pictures of exact and approximate equi-potentials and the lines of force of a dimensional electric point dipole are usually presented without mentioning the equation of lines of force. Generally, these pictures are generated by numerical methods. Smythe [2] provides a special method to obtain an involved expression for it, but in this letter we show that the usual and well-known approximation to the potential V ≈ 2K due to two point charges (α) separated by a distance a itself poses a more simply solvable problem that yields a simple expression for lines of force.
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