---
title: "An object is placed at a distance \\(d_o = 3f\\) to the left of a thin converging lens with focal length \\(f\\). Which of the following correctly pairs the resulting image distance \\(d_i\\) with the path of a light ray that travels parallel to the principal axis before reaching the lens?"
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url: "https://nerd-notes.com/ubq/117346/"
date_modified: "2026-08-04T06:51:53+00:00"
---

# An object is placed at a distance \(d_o = 3f\) to the left of a thin converging lens with focal length \(f\). Which of the following correctly pairs the resulting image distance \(d_i\) with the path of a light ray that travels parallel to the principal axis before reaching the lens?

An object is placed at a distance \(d_o = 3f\) to the left of a thin converging lens with focal length \(f\). Which of the following correctly pairs the resulting image distance \(d_i\) with the path of a light ray that travels parallel to the principal axis before reaching the lens?

![A horizontal line represents the principal axis. A thin converging lens is situated vertically at the center of the axis, represented by a vertical line segment with outward-pointing arrowheads at both ends. On both sides of the lens along the principal axis, tick marks are labeled F at distance f and 2F at distance 2f. An upright arrow representing the object stands on the principal axis to the left of the lens at a distance of 3f from the center, labeled Object. No ray paths, back-extensions, or image representations are shown. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1785826313-irrHmE.jpg)

- **A.** Image distance: \(d_i = 3f\) | Ray path: Refracts through the focal point on the far side of the lens
- **B.** Image distance: \(d_i = \dfrac{3}{2}f\) | Ray path: Refracts through the focal point on the far side of the lens
- **C.** Image distance: \(d_i = \dfrac{3}{2}f\) | Ray path: Continues straight through the center of the lens without deflecting
- **D.** Image distance: \(d_i = \dfrac{2}{3}f\) | Ray path: Diverges as if originating from the focal point on the near side of the lens

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/117346/*