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What is emitted by the hot metal filament in a cathode ray oscilloscope?

Correct answer: A. Electron

  • A. Electron
  • B. X-plates
  • C. Protons
  • D. Y-plates

Explanation

In a cathode ray oscilloscope (CRO), the hot metal filament emits electrons through a process called thermionic emission. When the filament is heated to a high temperature, electrons gain enough energy to escape from the surface of the metal and form a cloud of electrons around it. These emitted electrons are then accelerated and focused into a narrow beam by the electric field within the CRO tube. This electron beam is used to create the visual display on the screen of the CRO by striking a fluorescent coating, producing light that forms the waveform or pattern being analyzed.

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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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