current i=nAvde ( vd= mean drift velocity ) =n(4πD2)vde ∴i∝D2vd 200100=(2d)2(d)2×v′v ⇒v′=2×22v=8v
NEET UG 2024 — Physics Electromagnetism
A uniform wire of diameter d carries a current of 100 mA when the mean drift velocity of electrons in the wire is v. For a wire of diameter 2d of the same material to carry a current of 200 mA , the mean drift velocity of electrons in the wire is
Held on 30 Apr 2024 · Verified 9 Jul 2026.
4v
8v
v
2v
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