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Electric Current through Gases — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsElectric Current through Gases4 Marks
Question
Because to the space charge in a diode valve:
  1. The plate current decreases.
  2. The plate voltage increases.
  3. The rate of emission of thermions increases.
  4. The saturation current increases.
✓

Answer

  1. The plate current decreases.
Explanation:

A diode valve consists of a negatively-charged region between the cathode and anode, called the space charge region. This negatively-charged region repels the electrons coming from the cathode and, thus, it reduces the plate current. On the other hand, this region has no effect on plate voltage, rate of emission of thermions and the saturation current.

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