The question is: The brightness spot on the screen in the CRO is controlled by:
Correct answer: C. Grid
- A. Anode
- B. Cathode
- C. Grid
- D. Filament
Explanation
The brightness of the spot on the screen of a Cathode Ray Oscilloscope (CRO) is controlled by the grid which is a negatively charged electrode placed between the cathode and the anode. The grid controls the number of electrons that pass through it and reach the screen.Anode: The anode is the positively charged electrode that attracts the electrons. It does not control the brightness of the spot.Cathode: The cathode is the heated filament that emits electrons. It does not control the brightness of the spot.Filament: The filament is the part of the cathode that is heated to emit electrons. It does not control the brightness of the spot.
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About Electromagnetism
Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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