MCQ
In a CRT the acceleration of electrons is controlled by changing ________ between the cathode and anode:
- APotential difference
- BSpace
- CTemperature
- DNone of these
✓
Answer
- Potential difference
Explanation:
Positive potential is given to anode and negative potential is given to cathode. As a result of this potential difference, electrons generated by heating cathode are attracted towards anode due to this potential difference. If no potential difference is applied b/ w anode and cathode in CRT, no electron would strike the screen. It is because of this potential difference b/ w anode and cathode that the whole process occurs.
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