Physics for Scientists and Engineers with Modern Physics
Physics for Scientists and Engineers with Modern Physics
10th Edition
ISBN: 9781337553292
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 30, Problem 17P

You are working for a company that manufactures motors and generators. At the end of your first day of work, your supervisor explains to you that you will be assigned to a team that is designing a new homopolar generator. You have no idea what that is, but agree wholeheartedly to the assignment. At home that evening, you go online to learn about the homopolar generator and find the following. The homopolar generator, also called the Faraday disk, is a low-voltage, high-current electric generator. It consists of a rotating conducting disk with one stationary brush (a sliding electrical contact) at its axle and another at a point on its circumference as shown in Figure P30.17. A uniform magnetic field is applied perpendicular to the plane of the disk. When superconducting coils are used to produce a large magnetic field, a homopolar generator can have a power output of several megawatts. Such a generator is useful, for example, in purifying metals by electrolysis. If a voltage is applied to the output terminals of the generator, it runs in reverse as a homopolar motor capable of providing great torque, useful in ship propulsion. At work the next morning, your supervisor tells you that the homopolar generator under consideration will have a magnetic field of magnitude B = 0.900 T and the radius of the disk is r = 0.400 m. The desired emf to be generated with the device is E = 25.0 V . Your supervisor asks you to determine the required angular speed of the disk to achieve this result.

Figure P30.17

Chapter 30, Problem 17P, You are working for a company that manufactures motors and generators. At the end of your first day

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Chapter 30 Solutions

Physics for Scientists and Engineers with Modern Physics

Ch. 30 - A coil formed by wrapping 50 turns of wire in the...Ch. 30 - Prob. 8PCh. 30 - A toroid having a rectangular cross section (a =...Ch. 30 - A small airplane with a wingspan of 14.0 m is...Ch. 30 - A helicopter (Fig. P30.11) has blades of length...Ch. 30 - A 2.00-m length of wire is held in an eastwest...Ch. 30 - A metal rod of mass m slides without friction...Ch. 30 - Prob. 14PCh. 30 - Prob. 15PCh. 30 - Prob. 16PCh. 30 - You are working for a company that manufactures...Ch. 30 - You are working in a laboratory that uses motional...Ch. 30 - You are working in a factory that produces long...Ch. 30 - Prob. 20PCh. 30 - Within the green dashed circle show in Figure...Ch. 30 - Prob. 22PCh. 30 - Prob. 23PCh. 30 - Figure P30.24 (page 820) is a graph of the induced...Ch. 30 - The rotating loop in an AC generator is a square...Ch. 30 - In Figure P30.26, a semicircular conductor of...Ch. 30 - Prob. 27PCh. 30 - Prob. 28APCh. 30 - Prob. 29APCh. 30 - Prob. 30APCh. 30 - A circular coil enclosing an area of 100 cm2 is...Ch. 30 - Prob. 32APCh. 30 - A guitars steel string vibrates (see Fig. 30.5)....Ch. 30 - Prob. 34APCh. 30 - A conducting rod of length = 35.0 cm is free to...Ch. 30 - Prob. 36APCh. 30 - Prob. 37APCh. 30 - In Figure P30.38, the rolling axle, 1.50 m long,...Ch. 30 - Figure P30.39 shows a stationary conductor whose...Ch. 30 - Prob. 40APCh. 30 - Figure P30.41 shows a compact, circular coil with...Ch. 30 - Review. In Figure P30.42, a uniform magnetic field...Ch. 30 - An N-turn square coil with side and resistance R...Ch. 30 - A conducting rod of length moves with velocity v...Ch. 30 - A long, straight wire carries a current given by I...Ch. 30 - A rectangular loop of dimensions and w moves with...Ch. 30 - A thin wire = 30.0 cm long is held parallel to...Ch. 30 - Prob. 48CPCh. 30 - Prob. 49CPCh. 30 - Prob. 50CPCh. 30 - Review. The bar of mass m in Figure P30.51 is...
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