So, when the voltage difference between the plates is zero, or when we just don't have the plates there at all, the cathode rays are not bent, they just go right in a straight line, and they can be detected on this screen.

拐弯来测试它们是否带电,当两板之间电压为零，或者根本就,没有这两个板时，阴极射线是一条直线,它可以在屏幕上。

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