Essential University Physics: Volume 2 (3rd Edition)
3rd Edition
ISBN: 9780321976420
Author: Richard Wolfson
Publisher: PEARSON
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Chapter 30, Problem 59P
Fermat's principle states that a light ray's path is such that the time to traverse that path is an extremum (a minimum or a maximum) when compared with times for nearby paths. Show that Fermat's principle implies Snell's law by proving that a light ray going from point A in one medium to point B in a second medium will take the least time if it obeys Snell's law.
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When the sun is either rising or setting and appears to be just on the horizon, it is in fact below the horizon. The explanation for this seeming paradox is that light from the sun bends slightly when entering the earth’s atmosphere, as shown in Fig. Since our perception is based on the idea that light travels in straight lines, we perceive the light to be coming from an apparent position that is an angle d above the sun’s true position. (a) Make the simplifying assumptions that the atmosphere has uniform density, and hence uniform index of refraction n, and extends to a height h above the earth’s surface, at which point it abruptly stops. Show that the angle d is given by as attached. where R = 6378 km is the radius of the earth. (b) Calculate d using n = 1.0003 and h = 20 km. How does this compare to the angular radius of the sun, which is about one quarter of a degree? (In actuality a light ray from the sun bends gradually, not abruptly, since the density and refractive index of the…
Chapter 30 Solutions
Essential University Physics: Volume 2 (3rd Edition)
Ch. 30.1 - Prob. 30.1GICh. 30.2 - The figure shows the path of a light ray through...Ch. 30.3 - The glass prism in Fig. 30.11 has n = 1.5 and is...Ch. 30.4 - Prob. 30.4GICh. 30 - Prob. 1FTDCh. 30 - Why does a spoon appear bent when its in a glass...Ch. 30 - Prob. 3FTDCh. 30 - Prob. 4FTDCh. 30 - You send white light through two identical glass...Ch. 30 - In glass, which end of the visible spectrum has...
Ch. 30 - Prob. 7FTDCh. 30 - Why are polarizing sunglasses better than glasses...Ch. 30 - Under what conditions will the polarizing angle be...Ch. 30 - Through what angle should you rotate a mirror so...Ch. 30 - Prob. 12ECh. 30 - To what angular accuracy must two ostensibly...Ch. 30 - Prob. 14ECh. 30 - In which substance in Table 30.1 does the speed of...Ch. 30 - Information in a compact disc is stored in pits"...Ch. 30 - Light is incident on an air-glass interface, and...Ch. 30 - A light ray propagates in a transparent material...Ch. 30 - Light propagating in the glass (n = 1.52) wall of...Ch. 30 - Prob. 20ECh. 30 - Find the refractive index of a material for which...Ch. 30 - Find the critical angle for total internal...Ch. 30 - A drop of water is trapped in a block of ice....Ch. 30 - What is the critical angle for light propagating...Ch. 30 - Total internal reflection occurs at an interface...Ch. 30 - Blue and red laser beams strike an air-glass...Ch. 30 - White light propagating in air is incident at 45...Ch. 30 - Suppose the 60 angle in Fig. 30.18 is changed to...Ch. 30 - The refractive index of a human cornea is 1.40. If...Ch. 30 - Two plane mirrors make an angle . A light ray...Ch. 30 - An unlabeled bottle of liquid has spilled, and...Ch. 30 - A meter stick lies on the bottom of the...Ch. 30 - Prob. 33PCh. 30 - At the aquarium where you work, a fish has gone...Ch. 30 - Prob. 35PCh. 30 - You've dropped your car keys at night off the end...Ch. 30 - Laser eye surgery uses ultraviolet light with...Ch. 30 - Prob. 38PCh. 30 - Repeat Problem 38 for the case n = 1.75, = 40,...Ch. 30 - Find the minimum refractive index for the prism in...Ch. 30 - Where and in what direction would the main beam...Ch. 30 - Find the speed of light in a material for which...Ch. 30 - Prob. 43PCh. 30 - For the interface between air (refractive index 1)...Ch. 30 - A scuba diver sets off a camera flash at depth h...Ch. 30 - Suppose the red and blue beams of Exercise 26 are...Ch. 30 - In cataract surgery, ophthalmologists replace the...Ch. 30 - In a ruby laser, light is produced in a solid rod...Ch. 30 - Reconsider Example 30.4, now in a glass with n700...Ch. 30 - A cylindrical tank 2.4 m deep is full to the brim...Ch. 30 - For what diameter tank in Problem 50 will sunlight...Ch. 30 - Light is incident from air on the flat wall of a...Ch. 30 - Prob. 53PCh. 30 - Find an expression for the displacement x in Fig....Ch. 30 - Prob. 55PCh. 30 - (a) Differentiate the result of Problem 55 to show...Ch. 30 - Prob. 57PCh. 30 - Show that a three-dimensional corner reflector...Ch. 30 - Fermat's principle states that a light ray's path...Ch. 30 - Prob. 60PCh. 30 - A slab of transparent material has thickness d and...Ch. 30 - For common materials like glass, the wavelength...Ch. 30 - Figure 30.25a depicts lights path over a hot road,...Ch. 30 - Prob. 64PPCh. 30 - Figure 30.25b shows how continuous refraction in...Ch. 30 - The refractive index in the ionosphere is strongly...
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