railway RRB Technician Grade 1 Mock Test 2024 Physics Current, Resistance and Electricity Current Density
A copper wire of length 10 m and radius \(\left(10^{-2} / \sqrt{\pi}\right) \) m has electrical resistance of 10Ω . The current density in the wire for an electric field strength of 10 (V/m) is:
1
105 A/m2
2
104 A/m2
3
106 A/m2
4
10-5 A/m2