光滑绝缘的水平面上，两个可视为点电荷，电性相反的小球，由静止释放后的一小段时间内，则下列说法中正确的是
A．距离变大，库仑力变大
B．距离变大，库仑力变小
C．距离变小，库仑力变大
D．距离变小，库仑力变小
答案：B
题目分析：同种电荷间具有排斥力，所以释放后，两小球相互远离，即两球间的距离增大，故根据库伦定律
可得，两球间的库伦力减小，B正确，
点评：做本题的关键是正确掌握以及对库伦力公式的熟练
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