A long cylindrical wire (radius = 2.0 cm) carries a current of 40 A that is uniformly distributed over a cross section of the wire. What is the magnitude of the magnetic field at a point which is 1.5 cm from the axis of the wire?
a. 0.53 mT
b. 28 mT
c. 0.30 mT
d. 40 mT
e. 1.9 mT
c
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