---
title: "A thin wire carrying current \\(I\\) is shaped into a semicircular arc of radius \\(R\\), producing a magnetic field of magnitude \\(B_{\\text{arc}}\\)"
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url: "https://nerd-notes.com/ubq/118506/"
date_modified: "2026-08-04T08:11:10+00:00"
---

# A thin wire carrying current \(I\) is shaped into a semicircular arc of radius \(R\), producing a magnetic field of magnitude \(B_{\text{arc}}\)

A thin wire carrying current \(I\) is shaped into a semicircular arc of radius \(R\), producing a magnetic field of magnitude \(B_{\text{arc}}\)

![Two wire configurations are shown side by side, labeled (a) and (b). On the left, configuration (a) shows a semicircular wire arc of radius \(R\) lying in the plane of the page, open toward the bottom. A circular dot labeled \(P\) sits at the center of curvature of the semicircle. An arrow along the arc indicates current \(I\) flowing counterclockwise. A dashed straight line of length \(R\) extends vertically from point \(P\) to the top of the arc, labeled \(R\). On the right, configuration (b) shows a long vertical straight wire carrying current \(I\) directed upward, with an arrow labeled \(I\). A horizontal dashed line of length \(R\) extends from the wire to a circular dot labeled \(P\), with the segment labeled \(R\). No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1785831069-dB2Tni.jpg)

- **A.** \(\dfrac{\pi}{2}\)
- **B.** \(\dfrac{2}{\pi}\)
- **C.** \(\pi\)
- **D.** \(2\pi\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118506/*