Radius =1mm
N=100turns per mm
Current =1A
Magnetic field strength at the centre of the solenoid is,
B=μ0ni=4π×10−7×100×103×1⇒B=12.56×10−2T
A long solenoid of radius 1mm has 100turns per mm. If 1A current flows in the solenoid, the magnetic field strength at the centre of the solenoid is:
Held on 30 Apr 2022 · Verified 9 Jul 2026.
12.56×10−2T
12.56×10−4T
6.28×10−4T
6.28×10−2T
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