上海科技教育出版社2007年第2版、2009年第13次印刷的《物理》选修3-1教材,第5.4节“家庭作业与活动”中第8题为:在导出安培力的一般公式时,采取了分解B的方法如图1所示(原教材图5-38),能否用分解I的办法来推导这个公式?为什么?原解:上海科技教育出版社2007年第2版配套的教师用书的解答是:能够.根据原教材图5-38,把电流分解在垂直于磁感应强度方向,其有效电流为I_⊥=Isinθ,则F= Shanghai Science and Technology Education Press, Second Edition, 2007, 13th printed in 2009, “Physics” elective 3-1 textbook, Section 5.4 “Homework and Activities ” in the eighth title: Ampere derived in general Formula, take the method of decomposition B shown in Figure 1 (the original text Figure 5-38), can I decompose the method to derive this formula? Why? Original solution: Shanghai Science and Education Press 2007 2nd edition Supporting the teacher’s book answer is: Yes, according to the original text Figure 5-38, the current decomposition in the direction perpendicular to the magnetic flux density, the effective current I_⊥ = Isinθ, then F =