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Electric Current through Gases — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsElectric Current through Gases1 Mark
MCQ
The anode of a thermionic diode is connected to the negative terminal of a battery and the cathode to its positive terminal:
  • ✓
    No appreciable current will pass through the diode.
  • B
    A large current will pass through the diode from the anode to the cathode.
  • C
    A large current will pass through the diode from the cathode to the anode.
  • D
    The diode will be damaged.
✓

Answer

Correct option: A.
No appreciable current will pass through the diode.
If the anode is given a negative potential relative to the cathode, the electrons are pushed back to the cathode. Hence, no current will flow through the diode.

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