42. A long wire carries a current of 3.0 A along the axis of a long solenoid (radius = 3.0 cm, n = 900
turns/m, current = 30 mA). What is the magnitude of the magnetic field at a point 2.0 cm from the
axis of the solenoid? Neglect any end effects.
(A)34 μT
(B)64 μT
(C)30 μT
(D)45 μT
(E)4.0 μT
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