电势零点的选取不是完全任意的

Choice of Zero Point in Eelectric Potential Is Not Always Arbitrary

本文旨在说明电势零点的选取有一定的任意性，但不是完全任意的，它受到一定的限制。零势点选取的原则：首先必须使电场中各点的电势具有确定的数值，从而有明确的物理意义；其次使电势的表示式尽量简单。

This article points out that the zero point in electric potential may be but isnot always chosen arbitrarily. It is limited to a certain degree. The principle to choose zeropoint in the potential is that the electric potential of each point in electric field must first havea definite numerical value so as to make sense definitely in physics.Besides, the potenlial for-mula indicated should be made as simple as possible.