Two long parallel wires lie in the xz plane. One wire passes through the point (-2 m, 0, 0) and the other through the point (+2 m, 0, 0). The wires carry equal currents in the positive z direction.

1. The magnetic field at (-3 m, 0, 0) is in the negative y direction.
2. The magnetic field at (-1 m, 0, 0) is in the positive y direction.
3. The magnetic field at (+1 m, 0, 0) is in the positive y direction.
4. The magnetic field at (+3 m, 0, 0) is in the negative y direction.
A)1 and 2 are correct.
B) 1 and 4 are correct.
C) 2 and 3 are correct.
D) 3 and 4 are correct.
E) None of the above are correct.

Question

Two long parallel wires lie in the xz plane. One wire passes through the point (-2 m, 0, 0) and the other through the point (+2 m, 0, 0). The wires carry equal currents in the positive z direction.

1.	The magnetic field at (-3 m, 0, 0) is in the negative y direction.
2.	The magnetic field at (-1 m, 0, 0) is in the positive y direction.
3.	The magnetic field at (+1 m, 0, 0) is in the positive y direction.
4.	The magnetic field at (+3 m, 0, 0) is in the negative y direction.
A)1 and 2 are correct.
B)	1 and 4 are correct.
C)	2 and 3 are correct.
D)	3 and 4 are correct.
E)	None of the above are correct.

Quizplus · Accepted Answer

The magnetic field due to a long straight wire carrying current is given by the right-hand rule. For the wire at (-2 m, 0, 0), the magnetic field at (-3 m, 0, 0) is in the negative y direction, and at (-1 m, 0, 0) is in the positive y direction. Similarly, for the wire at (+2 m, 0, 0), the magnetic field at (+1 m, 0, 0) is in the positive y direction, and at (+3 m, 0, 0) is in the negative y direction.

Two Long Parallel Wires Lie in the Xz Plane