---
title: "Two identical laser pulses are emitted simultaneously toward parallel detectors separated from the sources by the same distance \\(L\\). Pulse 1 travels entirely through air, where the index of refraction is \\(n_1 = 1.00\\). Pulse 2 travels through a block of transparent glass of length \\(L\\) having an index of refraction \\(n_2 = 1.50\\). What is the ratio of the transit time of Pulse 1 to the transit time of Pulse 2, \\(\\dfrac{t_1}{t_2}\\)?"
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url: "https://nerd-notes.com/ubq/123176/"
date_modified: "2026-09-28T11:57:51+00:00"
---

# Two identical laser pulses are emitted simultaneously toward parallel detectors separated from the sources by the same distance \(L\). Pulse 1 travels entirely through air, where the index of refraction is \(n_1 = 1.00\). Pulse 2 travels through a block of transparent glass of length \(L\) having an index of refraction \(n_2 = 1.50\). What is the ratio of the transit time of Pulse 1 to the transit time of Pulse 2, \(\dfrac{t_1}{t_2}\)?

Two identical laser pulses are emitted simultaneously toward parallel detectors separated from the sources by the same distance \(L\). Pulse 1 travels entirely through air, where the index of refraction is \(n_1 = 1.00\). Pulse 2 travels through a block of transparent glass of length \(L\) having an index of refraction \(n_2 = 1.50\). What is the ratio of the transit time of Pulse 1 to the transit time of Pulse 2, \(\dfrac{t_1}{t_2}\)?

![A horizontal schematic showing two parallel light paths, one above the other. The top path starts at a small vertical rectangle on the left labeled Source 1 and extends horizontally to the right across open space labeled air to a small vertical rectangle on the right labeled Detector 1. The bottom path starts at a matching small vertical rectangle on the left labeled Source 2, passes horizontally through a light gray shaded rectangle labeled Glass, n = 1.50, and reaches a matching small vertical rectangle on the right labeled Detector 2. A horizontal dimension line with arrows at both ends spans the distance between the sources and detectors and is labeled L. A small horizontal right-pointing arrow labeled Pulse 1 sits in the top path, and a matching right-pointing arrow labeled Pulse 2 sits in the bottom path. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1790596671-DCBsMW.jpg)

- **A.** \(\dfrac{2}{3}\)
- **B.** \(1\)
- **C.** \(\dfrac{3}{2}\)
- **D.** \(\dfrac{9}{4}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123176/*