MCQ
In a $\text{CRT}$ the acceleration of electrons is controlled by changing $.......$ between the cathode and anode:
- ✓Potential difference
- BSpace
- CTemperature
- DNone of these
✓
Answer
Correct option: A.
Potential difference
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 $\text{CRT,}$ 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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