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1.A、B、C、D 四个同样的小通草球,用丝线吊着,已知 B 球吸引 A 球,B 球排斥 C 球,C 球能吸引 D 球,若 C球带正电,则把 A 球和 D 球靠近时,它们将( )。①相互吸引。②相互排斥。③不发生作用。④以上三种情况都有可能。分析:这是一个比较复杂的问题。要判断 A 球和D球是否带电及带什么电。由于 C 球带正电荷,且 C球能吸引 D 球,所以 D 球可能带相反电荷,即带有负电荷,也可能不带电。B 球排斥 C 球,则 B 球一定和 C球带有同种电荷,即 B 球带有正电荷。当 B 球和 A 球靠近时相互吸引,则 A 球可能不带电,也可能带有和
1.A, B, C, D Four similar small pass grass balls hanging on silk thread. Known B ball attracts A ball, B ball rejects C ball, C ball draws D ball, if C ball is positively charged, When you put A ball and D ball close, they will (). 1 attract each other. 2 mutually exclusive. 3 does not work. 4 more than three situations are possible. Analysis: This is a more complicated issue. To determine if the A ball and the D ball are charged and what the electricity is. Since the C ball has a positive charge and the C ball can attract the D ball, the D ball may have the opposite charge, that is, it may have a negative charge or may not be charged. If B ball rejects C ball, then B ball must have the same kind of charge as C ball, that is, B ball has positive charge. When the B ball and the A ball attract each other, the A ball may not be charged, and the A ball may also carry