Essential University Physics
4th Edition
ISBN: 9780134988566
Author: Wolfson, Richard
Publisher: Pearson Education,
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Textbook Question
Chapter 28, Problem 32E
You’re planning a semester in China, so you want to purchase a transformer to step the 220-V Chinese power down to 120 V to power your stereo. (a) If the transformer’s primary has 660 turns, how many should the secondary have? (b) You can save money with a transformer whose maximum primary current is 1.4 A. If your stereo draws 2.9 A, will this transformer work?
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Chapter 28 Solutions
Essential University Physics
Ch. 28.1 - What are the peak voltage and angular frequency of...Ch. 28.2 - Prob. 28.2GICh. 28.3 - You have an LC circuit that oscillates at a...Ch. 28.4 - You measure the capacitor and inductor voltages in...Ch. 28.5 - A resistor and capacitor are connected in series...Ch. 28.6 - A distribution line in a city supplies AC power at...Ch. 28 - Whats meant by the statement, A capacitor acts...Ch. 28 - Why does it make sense that inductive reactance...Ch. 28 - The same AC voltage appears across a capacitor and...Ch. 28 - When a particular inductor and capacitor are...
Ch. 28 - An inductor and capacitor are connected in series...Ch. 28 - Why is Equation 28.5 not a full description of the...Ch. 28 - The applied voltage in a series RLC circuit lags...Ch. 28 - The voltage across two components in series is...Ch. 28 - If you measure the rms voltages across the...Ch. 28 - A step-up transformer increases voltage, or energy...Ch. 28 - Much of Europe uses AC power at 230 V rms and 50...Ch. 28 - An AC current is given by I = 495 sin(9.43t), with...Ch. 28 - Prob. 13ECh. 28 - Find the rms current in a 1.0-F capacitor...Ch. 28 - A 470- resistor, 10-F capacitor, and 750-mH...Ch. 28 - Find the reactance of a 3.3-F capacitor at (a) 60...Ch. 28 - A 15-F capacitor carries 1.4 A rms. Whats its...Ch. 28 - A capacitor and a 1.8-k resistor pass the same...Ch. 28 - A 50-mH inductor is connected across a 10-V rms AC...Ch. 28 - Find the resonant frequency of an LC circuit...Ch. 28 - Prob. 21ECh. 28 - Your sister whos building the radio (Chapter 27...Ch. 28 - An LC circuit with a 20-F capacitor oscillates...Ch. 28 - A series RLC circuit has R = 75 k, L = 20 mH, and...Ch. 28 - Find the impedance at 10 kHz of a circuit...Ch. 28 - A series RLC circuit has R = 18 k, C = 14 F, and L...Ch. 28 - If the peak voltage applied to produce the curves...Ch. 28 - An electric drill draws 4.6 A rms at 120 V rms. If...Ch. 28 - A 40-W fluorescent lamp has power factor 0.85 and...Ch. 28 - An electric water heater draws 20 A rms at 240 V...Ch. 28 - For safety, medical equipment connected to...Ch. 28 - Youre planning a semester in China, so you want to...Ch. 28 - Example 28.2: In a European application, a...Ch. 28 - Example 28.2: A 0.470-μF capacitor and a 144-μH...Ch. 28 - Example 28.2: A radio transmitter applies 480 V...Ch. 28 - Example 28.2: You’re building a radio transmitter...Ch. 28 - Example 28.4: A crossover network in a loudspeaker...Ch. 28 - Example 28.4: The midrange speaker in a...Ch. 28 - Example 28.4: In Fig. 28.25, take and . A...Ch. 28 - For the circuit of Fig. 28.25. use a phasor...Ch. 28 - (a) A 2.2-H inductor is connected across 120-V...Ch. 28 - A 2.0-F capacitor has 1.0-k reactance. (a) Whats...Ch. 28 - Show that the unit of both capacitive and...Ch. 28 - Electroencephalography (EEG) elucidates brain...Ch. 28 - A 2.2-nF capacitor and one of unknown capacitance...Ch. 28 - Connections to the body for electrocardiography...Ch. 28 - The FM radio band covers the frequency range 88108...Ch. 28 - An LC circuit includes a 0.025-F capacitor and a...Ch. 28 - Prob. 49PCh. 28 - The 2420-F capacitor in Fig. 28.25 is initially...Ch. 28 - A damped LC circuit consists of a 0.15-F capacitor...Ch. 28 - A damped RLC circuit includes a 5.0- resistor and...Ch. 28 - An RLC circuit includes a 1.5-H inductor and a...Ch. 28 - The table below shows the ratio of peak voltage to...Ch. 28 - Figure 28.26 shows the phasor diagram for an RLC...Ch. 28 - An AC voltage of fixed amplitude is applied across...Ch. 28 - A series RLC circuit has resistance 127 and...Ch. 28 - A series RLC circuit has power factor 0.764 and...Ch. 28 - Youre Chief Financial Officer for a power company,...Ch. 28 - Prob. 60PCh. 28 - A power supply like that of Fig. 28.23 is supposed...Ch. 28 - An RLC circuit includes a 3.3-F capacitor and a...Ch. 28 - A series RLC circuit with R = 1.3 , L = 27 mH, and...Ch. 28 - Differentiate Equation 28.9 to find the current in...Ch. 28 - Find a second frequency where the current in the...Ch. 28 - Two capacitors are connected in parallel across a...Ch. 28 - A sine-wave generator with 15.0-V peak output is...Ch. 28 - For RLC circuits in which the resistance isnt too...Ch. 28 - A triangle wave swings linearly between voltages...Ch. 28 - Substitute the expression for q(t) in Equation...Ch. 28 - Although the maximum current flows in the speaker...Ch. 28 - A filter is a circuit designed to pass AC signals...Ch. 28 - A filter is a circuit designed to pass AC signals...Ch. 28 - A filter is a circuit designed to pass AC signals...Ch. 28 - A filter is a circuit designed to pass AC signals...
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