Delmar's Standard Textbook of Electricity (MindTap Course List)
6th Edition
ISBN: 9781285852706
Author: Stephen L. Herman
Publisher: Cengage Learning
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Textbook Question
Chapter 8, Problem 1PA
A circuit contains a 1000-Ω and a 300-Ω resistor connected in series with each other. The total circuit resistance must be reduced to a value of 1150 Ω. Using standard resistance values of 5% resistors discussed in Unit 5, explain how to change the present resistance value to the value desired.
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Find Laplace transform and the corresponding ROC for
x(t) = e−3sin(2t) u(t)dt
Three similar coils, connected in star, take a total
power of 1.5 kW, at a power factor of 0.2, from a
three-phase, 400 V, 50 Hz supply. Calculate: (a) the
resistance and inductance of each coil; (b) the line
currents if one of the coils is short-circuited.
(a) Three 20 µF capacitors are star-connected across
a 400 V, 50 Hz, three-phase, three-wire supply.
Calculate the current in each line. (b) If one of the
capacitors is short-circuited, calculate the line cur
rents. (c) If one of the capacitors is open-circuited,
calculate: the line currents and the p.d. across each
of the other two capacitors.
ANS:
1.525 A; 2.64 A, 2.64 A, 4.57 A; 1.32 A, 1.32 A, 0;
210 V
Chapter 8 Solutions
Delmar's Standard Textbook of Electricity (MindTap Course List)
Ch. 8 - Referto Figure 8-2. Replace the values shown with...Ch. 8 - 2. Refer to Figure 8-5. Replace the values shown...Ch. 8 - 3. Refer to the circuit shown in Figure 8-2....Ch. 8 - Refer to the circuit shown in Figure 6-22. The...Ch. 8 - Refer to Figure 8-21. Assume that the resistors...Ch. 8 - A circuit contains a 1000- and a 300- resistor...Ch. 8 - Two resistors are connected in series. One...Ch. 8 - A single-phase electric motor is connected to a...Ch. 8 - The hot water for the heating system for a small...Ch. 8 - Find the unknown values in the circuit if the...
Ch. 8 - Refer to the circuit shown in Figure 8-21 to solve...Ch. 8 - 3. Find the unknown values in the circuit if the...Ch. 8 - Refer to the circuit shown in Figure 8-25 to solve...Ch. 8 - 5. Find the unknown values in the circuit if the...Ch. 8 - Find the unknown values in the circuit if the...Ch. 8 - Refer to the circuit shown in Figure 8-26 to solve...Ch. 8 - ET E1 E2 E3 E41.248V IT I1 I2 I3 I4 RT R1 R2 R3 R4...Ch. 8 - Find the missing values for the circuit shown in...Ch. 8 - Find the missing values for the circuit shown in...
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