A long straight wire carries a current upward. At a point located to the east of the wire, what is the direction of the magnetic field produced by the current at that point?

• A. The magnetic field points toward the north.
• B. The magnetic field points downward.
• C. The magnetic field points toward the south.
• D. The magnetic field points upward.

Answer: (C)

Verified step by step guidance

1. Identify the direction of the current in the wire, which is given as upward (along the vertical axis).
2. Recall that the magnetic field around a current-carrying wire forms concentric circles around the wire, following the right-hand rule.
3. Apply the right-hand rule: Point the thumb of your right hand in the direction of the current (upward), then curl your fingers around the wire. Your fingers indicate the direction of the magnetic field.
4. At a point located to the east of the wire, observe the direction your curled fingers point. Since the current is upward, the magnetic field at the east side will be directed toward the south.
5. Conclude that the magnetic field at the point east of the wire points toward the south, consistent with the right-hand rule.