MCQ
The purpose of cathode in cathode ray tube is $......$
- ✓To emit the electrons
- BTo absorb the electrons
- CTo deflect the electrons
- DTo emit the protons
✓
Answer
Correct option: A.
To emit the electrons
The heated filament transfers its heat to the cathode the cathode coated by oxides of Barium or Strantium emit electrons on heating.
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