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</html><description>sub-atomic paticles Cathode rays Discharge tube Discharge tube is also called &#x201C;CROOK TUBE&#x201D;. It is made of a glass tube which consists of two metallic plates. One plate is connected to positive terminal of high voltage power supply and the other to negative terminal. The plate connected to the positive terminal is called &#x201C;ANODE&#x201D; the [&hellip;]</description><thumbnail_url>http://astan.lk/al_virtualclassroom/wp-content/uploads/2017/01/slide_2.jpg</thumbnail_url></oembed>

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