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Two cylindrical rods of uniform cross-se...

Two cylindrical rods of uniform cross-section area `A` and `2A`, having free electrons per unit volume `2n` and `n` respectively are joined in series. A current `I` flows through them in steady state. Then the ratio of drift velocity of free electron in left rod to drift velocity of electron in the
right rod is `((v_(L))/(v_(R)))` is

A

`(1)/(2)`

B

1

C

2

D

4

Text Solution

Verified by Experts

The correct Answer is:
B
(b) Since current `I = n e Avd` through both rods is same
`2 (n) eAv_(L) = n e (2A) v_(R)` or `(v_(L))/(v_(R)) = 1`
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A2Z-CURRENT ELECTRICITY-Section D - Chapter End Test
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  7. The resistance of the series combination of two resistances is S. When...

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  8. The total current supplied to the circuit by the battery is

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  10. An energy source will supply a constant current into the load if its i...

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  11. In a potentiometer experiment the balancing with a cell is at length 2...

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