Question

Which one of the following is true in the case of discharge lamps?

• A. The gas between the electrodes gets ionized because of applied colour on the lamp tube.
• B. The gas between the electrodes gets ionized because of applied potential difference.
• C. Ionized atoms travel at high speed and collide with unionized atoms and excite them to higher energy states.
• D. Ionized atoms travel at low speed and collide with inionized atoms and excite them to higher energy states.

Answer 1

Answer: (B), (C)

The correct options are
B

The gas between the electrodes gets ionized because of applied potential difference.

C

Ionized atoms travel at high speed and collide with unionized atoms and excite them to higher energy states.

The gas between the electrodes gets ionized because of applied potential difference. These ionized atoms travel at high speed and collide with ionized atoms and excite them to higher energy states. From there they come back to ground state. During this process the energy stored in them is liberated in terms of light.