In CRO, when cathode is heated by a filament, it emits:
Correct answer: B. Electrons
- A. Protons
- B. Electrons
- C. Rays
- D. Radiation
Explanation
When the cathode of a CRO is heated by a filament, a process known as thermionic emission occurs. In this process, the heat from the filament causes electrons to be emitted from the surface of the cathode. These emitted electrons form an electron beam, which is accelerated towards the anode by an electric field.
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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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