A current of 1 A is flowing on the sides of an equilateral triangle of side 4.5×10−2 m. The magnetic field at the centre of the triangle will be:
Held on 15 Apr 2018 · Verified 6 Jul 2026.
4×10−5 Wb/m2
Zero
2×10−5 Wb/m2
8×10−5 Wb/m2
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A solenoid has a core made of material with relative permeability $400$. The magnetic field produced in the interior of solenoid is $1.0$ T. The magnetic intensity in SI units is $\alpha \times 10^5$. The value of $\alpha$ is ______. (Free space permeability $\mu_0=4\pi \times 10^{-7}$ SI units.)
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