EBK PHYSICS FOR SCIENTISTS AND ENGINEER
9th Edition
ISBN: 8220100581557
Author: Jewett
Publisher: Cengage Learning US
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Textbook Question
Chapter 31, Problem 31.48P
A motor in normal operation carries a direct current of 0.850 A when connected to a 120-V power supply. The resistance of the motor windings is 11.8 Ω. While in normal operation, (a) what is the back emf generated by the motor? (b) At what rate is internal energy produced in the windings? (c) What If? Suppose a malfunction slops the motor shaft from rotating. At what rate will internal energy be produced in the windings in this case? (Most motors have a thermal switch that will turn off the motor to prevent overheating when this stalling occurs.)
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Chapter 31 Solutions
EBK PHYSICS FOR SCIENTISTS AND ENGINEER
Ch. 31 - A circular loop of wire is held in a uniform...Ch. 31 - In Figure 30.8a, a given applied force of...Ch. 31 - Figure 30.12 Figure 30.12 shows a circular loop of...Ch. 31 - Prob. 31.4QQCh. 31 - In an equal-arm balance from the early 20th...Ch. 31 - Figure OQS1.I is a graph of the magnetic flux...Ch. 31 - Prob. 31.2OQCh. 31 - A rectangular conducting loop is placed near a...Ch. 31 - A circular loop of wire with a radius of 4.0 cm is...Ch. 31 - A square, flat loop of wire is pulled at constant...
Ch. 31 - The bar in Figure OQ31.6 moves on rails to the...Ch. 31 - A bar magnet is held in a vertical orientation...Ch. 31 - What happens to the amplitude of the induced emf...Ch. 31 - Two coils are placed near each other as shown in...Ch. 31 - A circuit consists of a conducting movable bar and...Ch. 31 - Two rectangular loops of wire lie in the same...Ch. 31 - In Section 7.7, we defined conservative and...Ch. 31 - A spacecraft orbiting the Earth has a coil of wire...Ch. 31 - In a hydroelectric dam, how is energy produced...Ch. 31 - A bar magnet is dropped toward a conducting ring...Ch. 31 - A circular loop of wire is located in a uniform...Ch. 31 - A piece of aluminum is dropped vertically downward...Ch. 31 - Prob. 31.7CQCh. 31 - When the switch in Figure CQ31.8a is closed, a...Ch. 31 - Prob. 31.9CQCh. 31 - A loop of wire is moving near a long, straight...Ch. 31 - A flat loop of wire consisting of a single turn of...Ch. 31 - An instrument based on induced emf has been used...Ch. 31 - Transcranial magnetic stimulation (TMS) is a...Ch. 31 - A 25-turn circular coil of wire has diameter 1.00...Ch. 31 - A circular loop of wire of radius 12.0 cm is...Ch. 31 - A circular loop of wire of radius 12.0 cm is...Ch. 31 - Prob. 31.7PCh. 31 - A strong electromagnet produces a uniform magnetic...Ch. 31 - A 30-turn circular coil of radius 4.00 cm and...Ch. 31 - Scientific work is currently under way to...Ch. 31 - An aluminum ring of radius r1 = 5.00 cm and...Ch. 31 - An aluminum ring of radius r1 and resistance R is...Ch. 31 - Prob. 31.13PCh. 31 - A coil of 15 turns and radius 10.0 cm surrounds a...Ch. 31 - A square, single-turn wire loop = 1.00 cm on a...Ch. 31 - A long solenoid has n = 400 turns per meter and...Ch. 31 - A coil formed by wrapping 50 turns of wire in the...Ch. 31 - When a wire carries an AC current with a known...Ch. 31 - A toroid having a rectangular cross section (a =...Ch. 31 - Prob. 31.20PCh. 31 - A helicopter (Fig. P30.11) has blades of length...Ch. 31 - Use Lenzs law 10 answer the following questions...Ch. 31 - A truck is carrying a steel beam of length 15.0 in...Ch. 31 - A small airplane with a wingspan of 14.0 m is...Ch. 31 - A 2.00-m length of wire is held in an eastwest...Ch. 31 - Prob. 31.26PCh. 31 - Figure P31.26 shows a lop view of a bar that can...Ch. 31 - A metal rod of mass m slides without friction...Ch. 31 - A conducting rod of length moves on two...Ch. 31 - Prob. 31.30PCh. 31 - Review. Figure P31.31 shows a bar of mass m =...Ch. 31 - Review. Figure P31.31 shows a bar of mass m that...Ch. 31 - The homopolar generator, also called the Faraday...Ch. 31 - Prob. 31.34PCh. 31 - Review. Alter removing one string while...Ch. 31 - A rectangular coil with resistance R has N turns,...Ch. 31 - Prob. 31.37PCh. 31 - An astronaut is connected to her spacecraft by a...Ch. 31 - Within the green dashed circle show in Figure...Ch. 31 - Prob. 31.40PCh. 31 - Prob. 31.41PCh. 31 - 100-turn square coil of side 20.0 cm rotates about...Ch. 31 - Prob. 31.43PCh. 31 - Figure P30.24 (page 820) is a graph of the induced...Ch. 31 - In a 250-turn automobile alternator, the magnetic...Ch. 31 - In Figure P30.26, a semicircular conductor of...Ch. 31 - A long solenoid, with its axis along the x axis,...Ch. 31 - A motor in normal operation carries a direct...Ch. 31 - The rotating loop in an AC generator is a square...Ch. 31 - Prob. 31.50PCh. 31 - Prob. 31.51APCh. 31 - Suppose you wrap wire onto the core from a roll of...Ch. 31 - A circular coil enclosing an area of 100 cm2 is...Ch. 31 - A circular loop of wire of resistance R = 0.500 ...Ch. 31 - A rectangular loop of area A = 0.160 m2 is placed...Ch. 31 - A rectangular loop of area A is placed in a region...Ch. 31 - Strong magnetic fields are used in such medical...Ch. 31 - Consider the apparatus shown in Figure P30.32: a...Ch. 31 - A guitars steel string vibrates (see Fig. 30.5)....Ch. 31 - Why is the following situation impossible? A...Ch. 31 - The circuit in Figure P3 1.61 is located in a...Ch. 31 - Magnetic field values are often determined by...Ch. 31 - A conducting rod of length = 35.0 cm is free to...Ch. 31 - Review. A particle with a mass of 2.00 1016 kg...Ch. 31 - The plane of a square loop of wire with edge...Ch. 31 - In Figure P30.38, the rolling axle, 1.50 m long,...Ch. 31 - Figure P30.39 shows a stationary conductor whose...Ch. 31 - Prob. 31.68APCh. 31 - A small, circular washer of radius a = 0.500 cm is...Ch. 31 - Figure P30.41 shows a compact, circular coil with...Ch. 31 - Prob. 31.71APCh. 31 - Review. In Figure P30.42, a uniform magnetic field...Ch. 31 - An N-turn square coil with side and resistance R...Ch. 31 - A conducting rod of length moves with velocity v...Ch. 31 - The magnetic flux through a metal ring varies with...Ch. 31 - A rectangular loop of dimensions and w moves with...Ch. 31 - A long, straight wire carries a current given by I...Ch. 31 - A thin wire = 30.0 cm long is held parallel to...Ch. 31 - Prob. 31.79CPCh. 31 - An induction furnace uses electromagnetic...Ch. 31 - Prob. 31.81CPCh. 31 - A betatron is a device that accelerates electrons...Ch. 31 - Review. The bar of mass m in Figure P30.51 is...
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