【摘要】 根据磁与电的对偶性，提出了电场能量的第三种表达式，并进行了理论推导和举例验证。得到了与磁场能对偶的电场能新表达式。此式明确地表达了电场能是由自有能构成的物理特性，为利用互有能求多导体系统任意对导体之间的电场力提供了方便。更多还原

【Abstract】 According to the duality between magnetic field and electrical,the thind formula of the electrical field energy is given as well as the deduction and verification. The new formula is dual to the mag netic formula. This formula ex presses clearly the physical property that the electric field ergy is made up of the self-energy and mutual energy. With this the electric force among random two conductors in the multi-conductor system can be computed conveniently.更多还原