Essential University Physics (3rd Edition)
3rd Edition
ISBN: 9780134202709
Author: Richard Wolfson
Publisher: PEARSON
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Textbook Question
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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Chapter 30 Solutions
Essential University Physics (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 - Prob. 6FTD
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 - Prob. 22ECh. 30 - Prob. 23ECh. 30 - What is the critical angle for light propagating...Ch. 30 - Prob. 25ECh. 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 - Prob. 58PCh. 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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