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3. current electricity — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics3. current electricity1 Mark
MCQ
A cylindrical resistance is connected across battery $\varepsilon $ . Cylinder has uniform free electron density, mid part of cylinder has larger radius as shown in figure. Then $V_d$  (drift velocity) $V/S$ (distance across the length of the resistance)
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  • B

  • C

  • D

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Answer

Correct option: A.

a
$\mathrm{i}=\mathrm{JA}$

$\mathrm{J}=\mathrm{neVd}$

$\mathrm{i}=$ $\mathrm{Ane}$ $\mathrm{Vd}$

$\mathrm{i}=$ constant

$\mathrm{AVd}=$ Constant

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