Concept explainers
In a compact disc (CD), digital information is stored as a sequence of raised surfaces called “pits” and recessed surfaces called “lands.” Both pits and lands are highly reflective and are embedded in a thick plastic material with index of refraction n = 1.55 (Fig. 34-34). As a 780-nm wavelength (in air) laser scans across the pit-land sequence, the transition between a neighboring pit and land is sensed by- monitoring the intensity of reflected laser light from the CD. At the moment when half the width of the laser beam is reflected from the pit and the other half from the land, we want the two reflected halves of the beam to be 180° out of phase with each other. What should be the (minimum) height difference t between a pit and land? [When this light enters a detector, cancellation of the two out-of-phase halves of the beam produces a minimum detector output.]
FIGURE 34-34
Problem 65.
Want to see the full answer?
Check out a sample textbook solutionChapter 34 Solutions
PHYSICS FOR SCIEN & ENGNR W/MOD MAST
Additional Science Textbook Solutions
Tutorials in Introductory Physics
Physics (5th Edition)
University Physics with Modern Physics (14th Edition)
Modern Physics
Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
- Two polarizing sheets P1 and P2 are placed together with their transmission axes oriented at an angle to each other. What is when only 25% of the maximum transmitted light intensity passes through them?arrow_forwardOn a certain crystal, a first-order X-ray diffraction maximum is observed at an angle of 27.1° relative to its surface, using an X-ray source of unknown wavelength. Additionally, when illuminated with a different, this time of known wavelength 0.137 nm, a second-order maximum is detected at 37.3°. Determine (a) the spacing between the reflecting planes, and (b) the unknown wavelength.arrow_forwardThe movable mirror of a Michelson interferometer is attached to one end of a thin metal rod of length 23.3 mm. The other end of the rod is anchored so it does not move. As the temperature of the rod changes from 15°C to 25 C , a change of 14 fringes is observed. The light source is a He Ne laser, =632.8 nm . What is the change in length of the metal bar, and what is its thermal expansion coefficient?arrow_forward
- The structure of the NaCl crystal forms reflecting planes 0.541 nm apart. What is the smallest angle, measured from these planes, at which X-ray diffraction can be observed, if X-rays of wavelength 0.085 nm are used?arrow_forwardA beam of 580-nm light passes through two closely spaced glass plates at close to normal incidence as shown in Figure P27.23. For what minimum nonzero value of the plate separation d is the transmitted light bright?arrow_forwardProblem 8 In a compact disc (CD), digital information is stored as a sequence of raised surfaces called "pits" and recessed surfaces called "lands." Both pits and lands are highly reflec- tive and are embedded in a thick plastic material with index of refraction n = 1.55 (Fig. 34–34). As a 780-nm wave- length (in air) laser scans across the pit-land sequence, the transition between a neighboring pit and land is sensed by monitoring the intensity of reflected laser light from the CD. At the moment when half the width of the laser beam is reflected from the pit and the other half from the land, we want the two reflected halves of the beam to be 180° out of phase with each other. What should be the (minimum) height difference t between a pit and land? [When this light enters a detector, cancellation of the two out-of-phase halves of the beam produces a minimum detector output.] Reflecting "pit" Reflecting "land" Plastic AndY rdgil nwon ani ai dignolov often o is ni tm n = 1.55 pbirdi ods…arrow_forward
- A He-Ne gas laser which produces monochromatic light of a known wavelength a = 6.35 x 10-7 m is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 22° to the incident beam. How many lines per meter are there on the grating?arrow_forward..40 Go Figure 36-45 gives the pa- ß (rad) rameter of Eq. 36-20 versus the ßs sine of the angle in a two-slit inter- ference experiment using light of wavelength 435 nm. The vertical axis scale is set by B, = 80.0 rad. What are (a) the slit separation, (b) the total number of interference maxima (count them on both sides of the pattern's center), (c) the smallest angle for a maxima, and (d) the greatest angle for a minimum? Assume that none of the interference maxima are completely eliminated by a diffraction minimum. 0 sin 0 0.5 1 Figure 36-45 Problem 40.arrow_forwardA He-Ne gas laser which produces monochromatic light of a known wavelength ? =6.35 ? 10^7 ? is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 22 degrees to the incident beam. How many lines per meter are there on the grating?arrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningUniversity Physics Volume 3PhysicsISBN:9781938168185Author:William Moebs, Jeff SannyPublisher:OpenStaxPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning