Volume of wire will remain constant
So, A1l1=A2l2
⇒A2=nA1
The resistance of a wire with a length l, an area of A, and resistivity ρ is stated as R=Aρl.
Now, the new length is nl.
∴New resistance R′=A/nρnl⇒R′=ρn2Al
⇒R′=n2R
NEET UG 2017 — Physics Electromagnetism
The resistance of a wire is R ohm. If it is melted and stretched to n times its original length, its new resistance will be
Held on 30 Apr 2017 · Verified 9 Jul 2026.
nR
nR
n2R
n2R
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