在电场中电势相等的点构成的面叫等势面.显然,在同一等势面上移动电荷时,电场力不做功,由此,等势面也一定和电场线垂直,即跟场强的方向垂直.因为沿着电场线的方向电势越来越低,所以电场线总是由电势高的等势面指向电势低的等势面.若能灵活应用等势面的这些特点,很多复杂的问题就能迎刃而解. Obviously, when the charge is moved on the same equipotential surface, the electric field force does not work, and therefore the equipotential surface is also perpendicular to the electric field line, that is, the field strength The direction perpendicular to the direction of the electric field lines because the potential is getting lower and lower, so the electric field lines are always from the high potential of the potential surface pointing to the low potential of the potential if the potential application of such characteristics of the potential, a lot of complex The problem can be solved.