验电器是实验室常用来检验物体是否带电的仪器。例如,直接用玻璃棒或橡胶棒接触验电器的金属球,验电器金属杆下端的两片金属箔依然下垂,表明此时玻璃棒或橡胶棒不带电(如上图)。当用丝绸摩擦过的玻璃棒或毛皮摩擦过的橡胶棒接触验电器的金属球,验电器的两片金属箔便张开,表明玻璃棒或橡胶棒带有电荷。箔片之所以张开,是因为它带有同种电倚互相排斥而推开的。那么,验电器金属箔 Electroscopes are instruments that are commonly used by laboratories to test whether objects are charged. For example, directly touching a metal ball of an electroscope with a glass rod or a rubber rod, the two metal foils at the lower end of the metal pole of the electroscope are still sagging, indicating that the glass rod or the rubber rod is not energized at this time (as shown in the figure above). When a glass rod rubbed with silk or a rubber rod rubbed with a fur touches the metal sphere of the electroscope, the two metal foils of the electroscope open, indicating that the glass rod or the rubber rod is charged. The reason why the foil is opened is because it pushes away with the same kind of electricity. So, electroscope metal foil