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PUMPA - SMART LEARNING
எங்கள் ஆசிரியர்களுடன் 1-ஆன்-1 ஆலோசனை நேரத்தைப் பெறுங்கள். டாப்பர் ஆவதற்கு நாங்கள் பயிற்சி அளிப்போம்
Book Free DemoElectron generator:
When a discharge tube containing air or any gas at ambient pressure is exposed to a high electric voltage of \(10,000\) volts or more, no electricity flows through the air. When a high voltage of \(10,000\) volts is applied to the electrodes of a discharge tube containing air or any gas at an external pressure of about \(0.001\) mm of mercury, a greenish glow is observed on the discharge tube walls behind the anode.
![shutterstock1231369897 (2).jpg](https://resources.cdn.yaclass.in/cc7fe61a-46cd-46ea-a193-c088bedb8cab/shutterstock12313698972w504.jpg)
Electron generator
Note: Air is a good conductor of electricity.
- This observation demonstrates some invisible rays coming from the cathode.
- Hence, these rays are referred to as cathode rays.
- They were later given the name electrons.
Electron emission
Electrons:
Electrons are subatomic particles that revolve around the nucleus of an atom. They usually are negatively charged and much smaller than the nucleus of an atom.
![shutterstock_1912843453.jpg](https://resources.cdn.yaclass.in/f6f0eb03-9980-477b-8d7c-7f924210ea67/shutterstock1912843453w300.jpg)
Structure of atom