Q. 23

Expert-verified
Found in: Page 955

### Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

Book edition 4th
Author(s) Randall D. Knight
Pages 1240 pages
ISBN 9780133942651

# Two wide slits spaced apart are illuminated by blue laser light with a wavelength of . The interference pattern is observed on a screen behind the slits. How many bright fringes are seen in the central maximum that spans the distance between the first missing order on one side and the first missing order on the other side?

Number of bright fringes is

See the step by step solution

## Step1: Introduction

The dazzling fringe occurs when the crest of one wave coincides with the crest of another. The dark fringe occurs when the trough of one wave coincides with the trough of another, resulting in dark fringes.

## Step2: Find bright fringes

The number of brilliant fringes between this order and the central maximum is , for the missing order on one side of the central maximum. On the other hand, we have bright fringes for the missing order on the other side of the central maximum. As a result, the number of bright fringes seen between the first missing order on one side and the first missing order on the other side of the center maximum is .plus the central maximum itself, implying that the number is,

## Step3: Find bright fringes

Our current objective is to locate. The first missing order occurs when an interference maximum coincides with the first diffraction maximum, with denoting the order of the minimum. As a result, when , we can use the following relation to compute the missing order .

Therefore,