Cathode rays and their 15 properties
Definition of cathode rays:
Cathode rays are the group of fast moving negatively charged particles. These negatively charged particles are electrons. These rays are shot out at a high speed from the cathode of a discharge tube at a pressure below 0.01 mm of mercury.
15 Properties of Cathode rays:
1. Cathode rays travel in straight lines.
2. These rays are deflected by electric field. This is obvious because these rays are nothing but electrons.
3. These rays travel normally from the surface of cathode.
4. The direction of these rays is independent from the position of the anode.
5. These rays are independent of the nature of the gas and electrodes placed in the discharge tube.
6. Cathode rays possess high kinetic energy due to high speed, therefore they can exert high mechanical pressure.
7. Cathode rays produce heat when they fall on metal therefore the temperature of the metal rises.
8. These rays are also deflected by magnetic field.
9. These rays produce fluorescence.
10. They can affect a photographic plate.
11. These rays have small ionizing power.
12. Cathode rays travel with a high speed varies from 1/30th to 1/10 of speed of light.
13. These rays are also used to produce x –rays
14. They have some penetrating power.
15. Cathode rays may behave like waves. They exhibit the process of interference and diffraction.
These are the 15 properties of cathode rays. If you know more, please discuss.
Brain Teaser:
May you explain the reason of deflection of cathode rays under the influence of magnetic field. Please submit your answer in comment section.
As cathode ray is none other than “electron”.The electrons are negatively charged particles and thus the magnetic field exerts the force on negatively charged particles i.e.electron or cathode rays.
As we know that the magnetic field does not exert any force on rest charge but in this case it is exerting a force on electron because magnetic field exerts magnetic force on a moving charge.
Cathode Rays deflect from the magnetic field because they are negatively charged and there is repulsion. But they are attracted to the positive charge.
As we know that cathode Ray’s contain electrons which are -ve charge which are deflected by EF AND MF That’s why cathode Ray’s also deflect☺🙂