2015高考物理一轮复习课时跟踪检测(二十三)电场力的性质试题及完整解析答案-32（2015, college entrance examination review of physics a round of examination (twenty-three) the nature of the electric field force, questions and a complete analysis of the ans.doc

2015高考物理一轮复习课时跟踪检测(二十三)电场力的性质试题及完整解析答案-32（2015, college entrance examination review of physics a round of examination (twenty-three) the nature of the electric field force, questions and a complete analysis of the ans Zhang Bei learning plan system, daily share 2, with metal foil made of a charged ring, put in dry insulation on the desktop. Insulation cap made of friction with the hair with Xiaoming students after the cap from the top down slowly near rings, CM rings are attracted to the cap, as shown in the figure, judgment and analysis of this phenomenon, the following statement is correct (), the ring, and the cap with the charge, was immediately and all 5, (2013 Meishan simulation) as shown in Figure two, the amount of charge on charge Q1 and Q2 were placed in A and B, two distance L. With the L diameter smooth insulation semicircular ring, wearing a charged ball +q (considered as point charges), the P balance, the angle between PA and AB for alpha, regardless of the gravity of the small ball (==Q2), is [analysis] A. The ball by three forces FA, FB and FN in P and in balance, by geometric knowledge group, the FA and FB vertical. By Coulomb law can be obtained, and tan, alpha =, simultaneous solution, the A of B. By trying to show that FAFB, r1r2, so Q1Q2, so O field is not zero, so C and D are all wrong. 11, as shown in Figure two, the quality of both m A and B +q respectively with the ball and -q power, insulated wire suspension, the Coulomb attraction between two spheres is smaller than its gravity mg. Uniform field is coupled with a right level, two ball again remains stationary, the following conclusion is true (),,,, tension without electric field AB line to big [analysis] C, D. First, the analysis of AB overall balance integral application, suspension line tension is 2mg OA, and OA in the vertical direction, and then analyze the correct option C; taking B as the research object to the use of isolation, suspension line AB to the left, the tension force of t