An electric cell of e.m.f E, is connected across a copper wire of diameter d and length L. The drift velocity of electrons in the wire is v0. If the length of the wire is changed to 2L, the new drift velocity of electrons in the copper wire will be:
Correct answer: C. V/2
- A. V
- B. 2V
- C. V/2
- D. V/4
Explanation
At constant voltage, the drift velocity is inversely proportional to the length of the conductor. So If the length of the conductor is doubled, the drift velocity will become half of the original value.
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