Length =10m
Radius =(π10−2)m
Electrical resistance =10Ω
Electric field strength =10Vm−1
Current density, J=AI=RAV=RAEL
⇒J=10×π(π10−2)210×10=105Am−2
NEET UG 2022 — Physics Electromagnetism
A copper wire of length 10m and radius (π10−2)m has electrical resistance of 10Ω. The current density in the wire for an electric field strength of 10Vm−1 is:
Held on 30 Apr 2022 · Verified 9 Jul 2026.
106Am−2
10−5Am−2
105Am−2
104Am−2
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