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In the phenomenon of electric discharge through gases at low pressure, the coloured glow in the tube appears as a result of:

  1. A
    Collision between different electrons of the atoms of the gas
  2. B
    Excitation of electrons in the atoms
  3. C
    Collision between the atoms of the gas
  4. D
    Collisions between the charged particles emitted from the cathode and the atoms of the gas

Solution & Step-by-step Explanation

When a high voltage is applied, charged particles (electrons/ions) collide with gas atoms. These collisions transfer energy to the orbital electrons of the gas atoms, moving them to higher energy levels (Excitation). When these electrons return to lower energy states, they emit photons of specific wavelengths, creating the characteristic coloured glow.

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In the phenomenon of electric discharge through gases at low pressure, the coloured glow in the tube appears as a result of:
A
Collision between different electrons of the atoms of the gas
B
Excitation of electrons in the atoms
C
Collision between the atoms of the gas
D
Collisions between the charged particles emitted from the cathode and the atoms of the gas

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Dual Nature of MatterElectric DischargeAtomic Physics

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