How can you determine the direction of the magnetic field around a conductor?

How can you determine the direction of the magnetic field around a conductor?

• A. Right-hand rule
• B. Fleming's right-hand rule
• C. Left-hand rule
• D. Use a compass

Answer: (C)

The magnetic field around a straight current-carrying conductor runs in circles centered on the wire. To find its direction, use the right-hand rule: point your right thumb along the direction of the current, and your fingers curling around the wire show the direction of the magnetic field lines. For example, with current upward, the field encircles the wire counterclockwise when viewed from above; with current into the page, the field circles clockwise. A compass can help visualize the local field by aligning with the field, but it only gives the direction at a point rather than the full circular pattern. Fleming’s left-hand rule is for the force on a current in a magnetic field (motors), not for the field direction, and Fleming’s right-hand rule is used for generators.

The magnetic field around a straight current-carrying conductor runs in circles centered on the wire. To find its direction, use the right-hand rule: point your right thumb along the direction of the current, and your fingers curling around the wire show the direction of the magnetic field lines. For example, with current upward, the field encircles the wire counterclockwise when viewed from above; with current into the page, the field circles clockwise. A compass can help visualize the local field by aligning with the field, but it only gives the direction at a point rather than the full circular pattern. Fleming’s left-hand rule is for the force on a current in a magnetic field (motors), not for the field direction, and Fleming’s right-hand rule is used for generators.