27. Current enters a circular loop as shown below. At point P, where x = a, the magnetic field has the value
. The value of the magnetic field at x = -a is:
(A)0
(B)
(C)
(D)
(E)
i.
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統計: A(0), B(1), C(16), D(0), E(0) #3093868
統計: A(0), B(1), C(16), D(0), E(0) #3093868