54. Three long wires parallel to the x axis carry currents as shown. If I = 20 A, what is the magnitude of the magnetic field at the origin point O? ( magnetic constant μ0 = 4π × 10-7 T·m/A )5c99cc7c5e18c.jpg
(A) 19 μT
(B) 28 μT
(C) 37 μT
(D) 47 μT
(E) 58 μT

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統計: A(0), B(1), C(0), D(0), E(0) #1970708