Thomson also placed two magnets on either side of the tube, and observed that this magnetic field also deflected the cathode ray. The cathode ray tube is a vacuum tube containing one or more electron guns and a fluorescent screen used to view images.

Property 4: They are produced at the cathode (negatively charged electrode) and travel towards the anode. Property 3: Electric field and magnetic field deflect cathode rays. Property 2: Cathode rays are negatively charged. If cathode rays were charged particles, they must be deflected by both electric and. Property 1: Cathode rays travel in a straight line and can cast sharp shadows.

This indicated that the cathode ray was composed of negatively-charged particles. The beam struck the far end of the tube, producing a small fluorescent spot. The cathode is cylindrical in shape, and at the end of it, the layer of strontium and barium oxide is deposited which emit the high emission of electrons at the end of the tube. The cathode ray was deflected away from the negatively-charged electric plate and towards the positively-charged plate. The electrons are emitted from the highly emitted cathode. Thomson's experiment on constituents of cathode rays:Įxperiment - To test the properties of the particles, Thomson placed two oppositely-charged electric plates around the cathode ray. An electric discharge is passed through the tube.Įmission of blue rays can be seen from the cathode.Ĭonclusion - The blue rays emitted from cathode are cathode rays. Thomson’s experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. What did Thomson’s cathode ray tube experiments help scientists learn Summary.

William Crookes experiment for the discovery of cathode rays:Įxperiment - The figure shows a vacuum tube which has a gas at a very low pressure. Does the earths magnetic field produce a significant systematic error in this experiment Suppose the apparatus were rotated so that the earths field and the. Under these circumstances, the cathode rays did bend with the application of an electric field.

The blue glass seals and platinum connections indicate a production date of late 1800, so it is possibly an experimental tube from the time that the X-rays were invented. The discovery of cathode rays lead to the discovery of electrons : With the cathode ray tube, the cathode ejects electrons that are then accelerated through a charge, increasing their speed with each pass-through. This early odd English tube has a length of about 50 cm with a simple tiny rod anode and a heavy metal cathode. The three subatomic particles that constitute an atom are:

Cathode ray experiment significance