---
title: "A single continuous copper wire carrying a constant current \\(I\\) consists of four cylindrical segments connected in series: segment W has diameter \\(D\\) and length \\(L\\), segment X has diameter \\(2D\\) and length \\(L\\), segment Y has diameter \\(D\\) and length \\(2L\\), and segment Z has diameter \\(2D\\) and length \\(2L\\). Which of the following correctly ranks the magnitude of the electron drift velocity, \\(v_d\\), in the four segments?"
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url: "https://nerd-notes.com/ubq/120430/"
date_modified: "2026-08-23T04:34:37+00:00"
---

# A single continuous copper wire carrying a constant current \(I\) consists of four cylindrical segments connected in series: segment W has diameter \(D\) and length \(L\), segment X has diameter \(2D\) and length \(L\), segment Y has diameter \(D\) and length \(2L\), and segment Z has diameter \(2D\) and length \(2L\). Which of the following correctly ranks the magnitude of the electron drift velocity, \(v_d\), in the four segments?

A single continuous copper wire carrying a constant current \(I\) consists of four cylindrical segments connected in series: segment W has diameter \(D\) and length \(L\), segment X has diameter \(2D\) and length \(L\), segment Y has diameter \(D\) and length \(2L\), and segment Z has diameter \(2D\) and length \(2L\). Which of the following correctly ranks the magnitude of the electron drift velocity, \(v_d\), in the four segments?

![A horizontal diagram showing four connected cylindrical wire segments arranged end-to-end from left to right along a single horizontal axis. An arrow on the far left points rightward into the wire, labeled with current \(I\). From left to right: the first segment is labeled W, drawn with length \(L\) and vertical diameter \(D\); the second segment is labeled X, drawn with length \(L\) and a wider vertical diameter \(2D\); the third segment is labeled Y, drawn with length \(2L\) and vertical diameter \(D\); the fourth segment is labeled Z, drawn with length \(2L\) and vertical diameter \(2D\). All segments share a common horizontal centerline and have solid outlines with light gray shading. Dimension lines indicate the lengths and diameters of each segment. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1787459677-WLoBaX.jpg)

- **A.** \( (v_d)_W = (v_d)_Y > (v_d)_X = (v_d)_Z \)
- **B.** \( (v_d)_X = (v_d)_Z > (v_d)_W = (v_d)_Y \)
- **C.** \( (v_d)_W > (v_d)_Y > (v_d)_X > (v_d)_Z \)
- **D.** \( (v_d)_W = (v_d)_X = (v_d)_Y = (v_d)_Z \)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120430/*