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Electron, Photon, Photo-electric Effect and X-Rays — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsElectron, Photon, Photo-electric Effect and X-Rays1 Mark
MCQ
An oxide coated filament is useful in vacuum tubes because essentially
  • A
    It has high melting point
  • B
    It can withstand high temperatures
  • C
    It has good machanical strength
  • ✓
    It can emit electrons at relatively lower temperatures
✓

Answer

Correct option: D.
It can emit electrons at relatively lower temperatures

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