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A wire has a non-uniform cross-section a...

A wire has a non-uniform cross-section ai shown In figure. A steady current Is tlowint through it. Then the drift speed of tht electrons while going from A and B .........

A

Is constant throughout the wire.

B

decreases

C

increases

D

varies randomly

Text Solution

Verified by Experts

The correct Answer is:
B
decreases
From equation I = `"nev"_(d) A,`
`v_(d) = (I)/("neA")`
`therefore v_(d) prop (I)/(A)`
`therefore `Drift velocity decreases as area of cross section increases.
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