In CRO, when beam of electrons falls on a screen, it makes a visible spot because the screen is:
Correct answer: B. Fluorescent
- A. Rough
- B. Fluorescent
- C. Polished
- D. Clear
Explanation
The screen of a CRO is coated with a fluorescent material that emits light when struck by electrons. When the electron beam falls on the fluorescent screen, it causes the screen to fluoresce, producing a visible spot. The intensity of the spot depends on the energy of the electrons and the characteristics of the fluorescent material.
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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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