49. 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?
(A)10μT
(B) 19μT
(C) 28μT
(D) 37μT
(E) 52μT
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統計: A(2), B(8), C(1), D(0), E(0) #3224695
統計: A(2), B(8), C(1), D(0), E(0) #3224695