Field Due to a Long Wire: Two Very Long Parallel

question 63

Multiple Choice

Field due to a long wire: Two very long parallel wires in the xy-plane, a distance 2a apart, are parallel to the y-axis and carry equal currents I as shown in the figure. The +z direction points perpendicular to the xy-plane in a right-handed coordinate system. If both currents flow in the +y direction, which one of the graphs shown in the figure below best represents the z component of the net magnetic field, in the xy-plane, as a function of x? (Caution: These graphs are not magnetic field lines.)

• A) 1
• B) 2
• C) 3
• D) 4
• E) 5

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Definitions:

Radial

Related to the radius bone or the radial artery, often used in the context of the lateral aspect of the forearm.

Subnormal

Below the normal or average level, often relating to temperature, intelligence, or health status.

Tachypnea

Increased rate of respiration.

Bradypnea

An abnormally slow rate of respiration.