One way to measure the width of a narrow object is to examine its diffraction pattern. When laser light is shone on a long, thin object, such as a straightened strand of human hair, the resulting diffraction pattern has minima at the same angles as for a slit of the same width. If a laser of wavelength 632.8 nm directed onto a hair produces a diffraction pattern on a screen 4.10 m away and the width of the central maximum is 1.50 cm, what is the thickness of the hair? um

One way to measure the width of a narrow object is to examine its diffraction pattern. When laser light is shone on a long, thin object, such as a straightened strand of human hair, the resulting diffraction pattern has minima at the same angles as for a slit of the same width. If a laser of wavelength 632.8 nm directed onto a hair produces a diffraction pattern on a screen 4.10 m away and the width of the central maximum is 1.50 cm, what is the thickness of the hair? um

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter4: Diffraction

Section: Chapter Questions

Problem 82AP: Two slits each of width 1800 nm and separated by the center-to-center distance of 1200 nm are...

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Although we have discussed single-slit diffraction only for a slit, a similar result holds when light bends around a straight, thin object, such as a strand of hair. In that case, a is the width of the strand. From actual lab measurements on a human hair, it was found that when a beam of light of wavelength 632.8nm was shone on a single strand of hair, and the diffracted light was viewed on a screen 1.25m away, the first dark fringes on either side of the central bright spot were 5.22cm apart. How thick was this strand of hair?
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let a beam of x rays of wavelength 0.125 nm be incident on an NaCl crystal at angle u 45.0° to the top face of the crystal and a family of reflecting planes. Let the reflecting planes have separation d = 0.252 nm. The crystal is turned through angle f around an axis perpendicular to the plane of the page until these reflecting planes give diffraction maxima. What are the (a) smaller and (b) larger value of f if the crystal is turned clockwise and the (c) smaller and (d) larger value of f if it is turned counterclockwise?
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