Same chapter3 marksDifficulty: Medium
Three resistors of 6 Ω each are joined in parallel and the combination is connected across a 12 V battery of negligible internal resistance. Find the current drawn.
Current Electricity
3 marksDifficulty: Medium
What is drift velocity, and how is it related to the current in a conductor?
Original Khojo Papers practice question — not from a past board paper.
Answer
Drift velocity is the small average velocity the free electrons acquire along the conductor under an applied field, superimposed on their much larger random thermal motion. The current is I = nAev_d, where n is the number of free electrons per unit volume, A the area of cross-section and e the electronic charge.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The drift velocity is of the order of a millimetre per second, though the signal travels almost at the speed of light.
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