---
title: "Monochromatic red light (wavelength \\(\\lambda_{\\text{red}} = 650 \\text{ nm}\\)) and monochromatic blue light (wavelength \\(\\lambda_{\\text{blue}} = 450 \\text{ nm}\\)) are shone individually through a single slit of width \\(a\\) onto a viewing screen at a fixed distance \\(L\\) from the slit. Which choice correctly compares the width of the central maximum produced by red light to that produced by blue light, and describes the effect on the width of the central maximum if the slit width \\(a\\) is increased?"
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url: "https://nerd-notes.com/ubq/116635/"
date_modified: "2026-08-04T05:25:22+00:00"
---

# Monochromatic red light (wavelength \(\lambda_{\text{red}} = 650 \text{ nm}\)) and monochromatic blue light (wavelength \(\lambda_{\text{blue}} = 450 \text{ nm}\)) are shone individually through a single slit of width \(a\) onto a viewing screen at a fixed distance \(L\) from the slit. Which choice correctly compares the width of the central maximum produced by red light to that produced by blue light, and describes the effect on the width of the central maximum if the slit width \(a\) is increased?

Monochromatic red light (wavelength \(\lambda_{\text{red}} = 650 \text{ nm}\)) and monochromatic blue light (wavelength \(\lambda_{\text{blue}} = 450 \text{ nm}\)) are shone individually through a single slit of width \(a\) onto a viewing screen at a fixed distance \(L\) from the slit. Which choice correctly compares the width of the central maximum produced by red light to that produced by blue light, and describes the effect on the width of the central maximum if the slit width \(a\) is increased?

![A monochromatic light beam travels horizontally from left to right through a thin vertical barrier containing a single narrow slit of width a. Beyond the slit, the light wave spreads out toward a vertical screen located a distance L away, forming a wide central bright maximum flanked by smaller secondary maxima. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1785821121-Sq7h3N.jpg)

- **A.** The red central maximum is narrower than the blue central maximum; increasing \(a\) causes the central maximum width to decrease.
- **B.** The red central maximum is wider than the blue central maximum; increasing \(a\) causes the central maximum width to decrease.
- **C.** The red central maximum is wider than the blue central maximum; increasing \(a\) causes the central maximum width to increase.
- **D.** The red central maximum is narrower than the blue central maximum; increasing \(a\) causes the central maximum width to increase.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/116635/*