CBSE-XI-Physics
35: Magnetic Field due to a Current
- #4A transmission wire carries a current of 100 A. What would be the magnetic field B at a point on the road if the wire is 8 m above the road?Ans : Given:
Magnitude of current, I = 100 A
Separation of the road from the wire, d = 8 m
Thus, the magnetic field is given by
`` B=\frac{{\mu }_{0}i}{2\,\mathrm{\,\pi \,}d}=\frac{2\times {10}^{-7}\times 100}{8}=2.5\,\mathrm{\,mT\,}``
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