CH37 - CHAPTER 37INTERFERENCE AND DIFFRACTION ActivPhysics...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: CHAPTER 37INTERFERENCE AND DIFFRACTION ActivPhysics can help with these problems: Activities in Section 16, Physical Optics Section 37- 2:Double-Slit Interference Problem 1. A double-slit system is used to measure the wavelength of light. The system has slit spacing d = 15 m and slit-to- screen distance L m = = 2 2 1 . m. If the maximum in the interference pattern occurs 71 . cm from screen center, what is the wavelength? Solution The experimental arrangement and geometrical approximations valid for Equation 37-2a are satisfied for the situation and data given, so = = = y d mL bright cm m m nm. = = = ( . . )( ) 71 2 2 15 1 484 (In particular, d and 1 2 3 23 10 185 = = - . . is small.) Problem 2. A double-slit experiment with d L = = 0 025 75 . mm and cm uses 550-nm light. What is the spacing between adjacent bright fringes? Solution Assume that the geometrical arrangement of the source, slits, and screen is that for which Equations 37-2a and b apply. The spacing of bright fringes is y L d = = = = = ( )( ) ( . ) . 550 75 0 025 165 nm cm mm cm. Problem 3. A double-slit experiment has slit spacing 012 . mm. (a) What should be the slit-to-screen distance L if the bright fringes are to be 5 0 . mm apart when the slits are illuminated with 633-nm laser light? (b) What will be the fringe spacing with 480-nm light? Solution The particular geometry of this type of double-slit experiment is described in the paragraphs preceding Equations 37-2a and b. (a) The spacing of bright fringes on the screen is y L d L = = = = = , ( . )( ) ( ) . so mm mm nm cm. 012 5 633 94 8 (b) For two different wavelengths, the ratio of the spacings is = y y = = ; therefore = = y ( )( ) . 5 480 633 3 79 mm mm. = Problem 4. With two slits separated by 0 37 . mm, the interference pattern has bright fringes with angular spacing 0.065 . What is the wavelength of the light illuminating the slits? Solution For small angles, the interference fringes are evenly spaced, with = = d (see Equation 37-1a). Thus, = = ( . )( . )( ) 0 37 0 065 180 420 mm nm. = Problem 5. The green line of gaseous mercury at 546 nm falls on a double-slit apparatus. If the fifth dark fringe is at 0.113 from the centerline, what is the slit separation? Solution The interference minima fall at angles given by Equation 37-1b; therefore d = + = = ( ) sin . ( ) sin . 4 4 5 546 0113 1 2 = = nm 125 . mm. (Note that m = 0 gives the first dark fringe.) CHAPTER 37 Problem 6. What is the angular position of the second-order bright fringe in a double-slit system with 1.5- m slit spacing if the light has wavelength (a) 400 nm or (b) 700 nm?...
View Full Document

This note was uploaded on 05/12/2008 for the course PHYS 299 taught by Professor Hoston,amahd,bakanowski during the Spring '08 term at University of Louisville.

Page1 / 26

CH37 - CHAPTER 37INTERFERENCE AND DIFFRACTION ActivPhysics...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online