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> 轻小的金属杆A，用一根绝缘细线悬挂在天花板下，下列判断它是否带电的各种方法中不正确的是 A.用验电器的金属球跟它接触，若箔片张开，A肯定带电 B.用带电小球B靠近它，若它被吸引，则A肯定带电 C.用带电小球B靠近它，若它被推开，A肯定带电 D.用纸屑靠近它，若纸屑被吸引，A肯定带电

问题：

发布时间：2024-09-12

轻小的金属杆A，用一根绝缘细线悬挂在天花板下，下列判断它是否带电的各种方法中不正确的是

A.用验电器的金属球跟它接触，若箔片张开，A肯定带电
B.用带电小球B靠近它，若它被吸引，则A肯定带电
C.用带电小球B靠近它，若它被推开，A肯定带电
D.用纸屑靠近它，若纸屑被吸引，A肯定带电

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