Q. 43.5( 2 Votes )
A 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?
Current through the transmission wire: I = 100 A
Distance between wire and the road : d = 8 m
By Ampere’s Law for a current carrying wire is
B is the magnitude of magnetic field,
μ0 is the permeability of free space
μ0= 4π × 10-7 T mA-1
d is the distance between the current carrying wire and the required point.
Substituting we get,
B = 2.5× 10-6 T
Hence, magnitude of magnetic field at a point on the road due to current carrying transmission wire is 2.5× 10-6 T.
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