13. 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
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