自感串联佯谬及解释

长直螺线管的自感系数公式L＝μ0b^2V忽略了长直螺线管磁场的端点效应，并认为磁场局限在螺线管内的体积中。长直螺线管串联时，如果应用公式L＝μ0n^2V,不管它们之间的位置关系如何，螺线管之间不存在互感。串联后的总自感系数等于各螺线管自感系数之和，所以顺接和反接公式都不成立。实际上，长直螺线管串联时，如果它们之间的距离不太远，由于其端点效应它们之间有互感。顺接、反接公式只是在重叠绕制的螺线管、螺绕环上的线圈等情况时适用。

SELF-INDUCTANCE SERIES PARADOX AND ITS EXPLANATION

The formula VnL20m= overlooks the terminal effect of the magnetic field in a long straight solenoid. According to this formula, the magnetic field is restricted within the volume of the solenoid. If VnL20m= is used, there is mo mutual inductance between the series solenoids in whatever way they are put. Because the total self-inductance coefficient is the sum of all the solenoids?coefficients, the formulas are not valid in same of opposite directions. In fact, when the long straight solenoids are in series connection at a little distance between them, there is mutual inductance, which is the result of their terminal effects. The formulas are only valid to the solenoids which are coiled overlappedly.