MCQ
How can the brightness of the pattern on the screen or cathode ray tube be changed?
- ✓By changing the negative potential on grid.
- BBy changing the positive potential on grid.
- CWe can't increase the brightness
- DNone of the above
✓
Answer
Correct option: A.
By changing the negative potential on grid.
By changing the negative potential of the grid, we can control the number of electrons per unit time or the current in the cathode ray tube which changes the brightness.
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