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Electric Current in Conductors — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsElectric Current in Conductors1 Mark
Question
When no current is passed through a conductor:
  1. The free electrons do not move.
  2. The average speed of a free electron over a large period of time is zero.
  3. The average velocity of a free electron over a large period of time is zero.
  4. The average of the velocities of all the free electrons at an instant is zero.
✓

Answer

  1. The average velocity of a free electron over a large period of time is zero.
  2. The average of the velocities of all the free electrons at an instant is zero.

Explanation:

No current is passed through a conductor means. That the average velocity of a free elecron over a large period of time is zero or the average of the velocity of all the free electrons at an instant is zero.

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