The Crooke's tube is a Cathode-ray tube, which is a cylindrical tube with the cathode at one end, anode at the other, and a metal plate between them. One end of the plate containing a horizontal slit is bent at right angles to the length and its remaining surface is coated with a fluorescent material which shows the path of the beam. When either a magnet or a charged rod is brought near the tube the beam will be deflected in accordance with well-known laws, from which the polarity of the charge is determinable.
|Bar magnet or cow magnet||021-5C|
|Crooke's tube and induction coil||021-17B|