Three copper rods are subjected to different potential difference. Compare the drift speed of electrons through them. Assume that all $3$ are at the same temperature.
Length
Diameter
Potential difference
$(A)$
$L$
$3d$
$V$
$(B)$
$2L$
$d$
$2V$
$(C)$
$3L$
$2d$
$2V$
A$v_A = v_B > v_C$
B$v_A > v_B > v_C$
C$v_A < v_B < v_C$
D
None of these
Medium
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A$v_A = v_B > v_C$
a $\mathrm{i}=\mathrm{neAV}_{\mathrm{drift}}=\frac{\mathrm{V}}{\mathrm{R}}$
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