---
title: "Two long, straight parallel wires in the plane of the page are separated by a distance \\(2d\\). Wire 1 carries a current \\(I\\) directed toward the top of the page, and Wire 2 carries an equal current \\(I\\) directed toward the bottom of the page. Point \\(P_1\\) is located halfway between the wires. Point \\(P_2\\) is located a distance \\(d\\) to the left of Wire 1, and Point \\(P_3\\) is located a distance \\(d\\) to the right of Wire 2. Which of the following correctly ranks the magnitudes of the net magnetic fields \\(B_1\\), \\(B_2\\), and \\(B_3\\) at points \\(P_1\\), \\(P_2\\), and \\(P_3\\), respectively?"
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url: "https://nerd-notes.com/ubq/118485/"
date_modified: "2026-08-04T08:11:03+00:00"
---

# Two long, straight parallel wires in the plane of the page are separated by a distance \(2d\). Wire 1 carries a current \(I\) directed toward the top of the page, and Wire 2 carries an equal current \(I\) directed toward the bottom of the page. Point \(P_1\) is located halfway between the wires. Point \(P_2\) is located a distance \(d\) to the left of Wire 1, and Point \(P_3\) is located a distance \(d\) to the right of Wire 2. Which of the following correctly ranks the magnitudes of the net magnetic fields \(B_1\), \(B_2\), and \(B_3\) at points \(P_1\), \(P_2\), and \(P_3\), respectively?

Two long, straight parallel wires in the plane of the page are separated by a distance \(2d\). Wire 1 carries a current \(I\) directed toward the top of the page, and Wire 2 carries an equal current \(I\) directed toward the bottom of the page. Point \(P_1\) is located halfway between the wires. Point \(P_2\) is located a distance \(d\) to the left of Wire 1, and Point \(P_3\) is located a distance \(d\) to the right of Wire 2. Which of the following correctly ranks the magnitudes of the net magnetic fields \(B_1\), \(B_2\), and \(B_3\) at points \(P_1\), \(P_2\), and \(P_3\), respectively?

![A vertical diagram showing two long parallel vertical lines representing wires, separated horizontally by a distance 2d. The left line is labeled Wire 1 and has a vertical arrow pointing upward labeled I. The right line is labeled Wire 2 and has a vertical arrow pointing downward labeled I. Three points are marked in the plane: Point P_1 is located halfway between Wire 1 and Wire 2, at distance d from each wire. Point P_2 is located to the left of Wire 1, at a horizontal distance d from Wire 1. Point P_3 is located to the right of Wire 2, at a horizontal distance d from Wire 2. Horizontal dashed dimension lines indicate the distance d between P_2 and Wire 1, between Wire 1 and P_1, between P_1 and Wire 2, and between Wire 2 and P_3. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1785831062-S3jev7.jpg)

- **A.** \(B_2 = B_3 > B_1\)
- **B.** \(B_1 = B_2 = B_3\)
- **C.** \(B_1 > B_2 = B_3\)
- **D.** \(B_1 > B_2 > B_3\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118485/*