Introductory Circuit Analysis
13th Edition
ISBN: 9780133923919
Author: Boylestad, Robert L.
Publisher: Pearson Education
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Textbook Question
Chapter 20, Problem 23P
a. An air-core coil is connected to a 200 V, 60 Hz source. The current is found to be 4 A, and a wattmeter reading of 80 W is observed. Find the effective resistance and the inductance of the coil.
b. A brass core is inserted in the coil. The ammeter reads 3 A, and the wattmeter reads 90 W Calculate the effective resistance of the core Explain the increase over the value in part (a).
c. If a solid iron core is inserted in the coil, the current is found to be 2 A, and the wattmeter reads 60 W. Calculate the resistance and inductance of the coil. Compare these values to the values in part (a), and account for the changes.
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Chapter 20 Solutions
Introductory Circuit Analysis
Ch. 20 - For the battery of bulbs (purely resistive)...Ch. 20 - For the network of Fig. 20.49 : a. Find the...Ch. 20 - For the network of Fig. 20.50 : a. Determine the...Ch. 20 - For the system of Fig. 20.51 : a. Find the total...Ch. 20 - For the system of Fig. 20.52 : a. Find PT, QT. and...Ch. 20 - 6. For the system of Fig. 20.53 : a. Find PT, QT....Ch. 20 - For the network of Fig. 20.54 : a. Find the type...Ch. 20 - For the circuit of Fig. 20.55: a. Find the...Ch. 20 - For the network of Fig. 20.56 : a. Find Is. b....Ch. 20 - Repeat Problem 9 for the network of Fig. 20.57.
Ch. 20 - For the network of Fig. 20.58: a. Find the average...Ch. 20 - An electrical system is rated 10 kVA, 200 V at a...Ch. 20 - An electrical system is rated 5 kVA, 120 V, at a...Ch. 20 - For the system of Fig. 20.59: a. Find the total...Ch. 20 - Repeat Problem 14 for the system of Fig. 20.60.Ch. 20 - For the circuit of Fig. 20.61: Find the total...Ch. 20 - For the circuit of Fig. 20.62: Find the total...Ch. 20 - Prob. 18PCh. 20 - The load on a 120 V, 60 Hz supply is 5 kW...Ch. 20 - The loading of a factory on a 1000 V, 60 Hz system...Ch. 20 - a. A wattmeter is connected with its current coil...Ch. 20 - The voltage source in Fig. 20.64 delivers 660 VA...Ch. 20 - a. An air-core coil is connected to a 200 V, 60 Hz...Ch. 20 - a. The inductance of an air-core coil is 0.08 H....Ch. 20 - Using PSpice or Multisim, obtain a plot of...
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