Loose Leaf for Engineering Circuit Analysis Format: Loose-leaf
9th Edition
ISBN: 9781259989452
Author: Hayt
Publisher: Mcgraw Hill Publishers
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Textbook Question
Chapter 12, Problem 43E
(a) Is the load represented in Fig. 12.41 considered a three-phase load? Explain. (b) If ZAN = 1 − j7 Ω, 
and ZAB = 2 + j Ω, calculate all phase (and line) currents and voltages assuming a phase to neutral voltage of 120 VAC (the two phases are 180° out of phase). (c) Under what circumstances does current flow in the neutral wire?
FIGURE 12.41
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Students have asked these similar questions
1. What is the main direct cause of reactive power in AC system?
A. Resistance of transmission lines
B. Inductance and capacitance in the loads
C. Ideal transformer connected in the system
D. Power produced by generator
2. "Reactive power in a system is dissipated generally as thermal energy?"
A. TRUE
B. FALSE
3. Which of the following statements are correct for three phase circuit:
A. Sum of all the three phase currents is zero in unbalanced network
B. Total power transfer to load is constant with time
C. Neutral conductor is same size in terms of material used as in single phase conductors
D. Net apparent power consumed is equal to real power
current - 1=?, and the power factor - cosp =?.
4.
An out of balance three phase star connected load has the following complex currents:
I₁ = lejº,A, I₂ =le¯6⁰,A and I₁=1e¹j6⁰, A. This load is supplied by a four wire
power line from a balance voltage source. Find the r.m.s. value of the neutral current Io =?
Wait
to th
Please answer quickly
"In series-connected ac circuit, the total voltage across the circuit is always equal to the sum of the magnitude (only) of the individual voltage across each element."
True
False
The power factor is equal to cosine of the phase difference.
True
False
A leading power factor means that the circuit is predominantly capacitive in nature.
True
False
"Since most loads are resistive in nature (e.g. motors), improvement of power factor is done by connecting capacitor banks or a synchronous condenser "
True
False
Chapter 12 Solutions
Loose Leaf for Engineering Circuit Analysis Format: Loose-leaf
Ch. 12.1 - Let and . Find (a) Vad; (b) Vbc; (c) Vcd.Ch. 12.2 - Prob. 2PCh. 12.2 - Modify Fig. 12.9 by adding a 1.5 resistance to...Ch. 12.3 - A balanced three-phase three-wire system has a...Ch. 12.3 - A balanced three-phase three-wire system has a...Ch. 12.3 - Three balanced Y-connected loads are installed on...Ch. 12.4 - Each phase of a balanced three-phase -connected...Ch. 12.4 - Prob. 8PCh. 12.5 - Determine the wattmeter reading in Fig. 12.24,...Ch. 12.5 - Prob. 10P
Ch. 12 - Prob. 1ECh. 12 - Prob. 2ECh. 12 - Prob. 3ECh. 12 - Describe what is meant by a polyphase source,...Ch. 12 - Prob. 5ECh. 12 - Prob. 6ECh. 12 - Prob. 7ECh. 12 - Prob. 8ECh. 12 - Prob. 9ECh. 12 - Prob. 10ECh. 12 - The single-phase three-wire system of Fig. 12.31...Ch. 12 - Prob. 12ECh. 12 - Referring to the balanced load represented in Fig....Ch. 12 - Prob. 14ECh. 12 - Prob. 15ECh. 12 - Consider a simple positive phase sequence,...Ch. 12 - Assume the system shown in Fig. 12.34 is balanced,...Ch. 12 - Repeat Exercise 17 with Rw = 10 , and verify your...Ch. 12 - Prob. 19ECh. 12 - Prob. 20ECh. 12 - Prob. 21ECh. 12 - Prob. 22ECh. 12 - A three-phase system is constructed from a...Ch. 12 - Prob. 24ECh. 12 - Each load in the circuit of Fig. 12.34 is composed...Ch. 12 - Prob. 26ECh. 12 - Prob. 27ECh. 12 - A three-phase load is to be powered by a...Ch. 12 - For the two situations described in Exercise 28,...Ch. 12 - Prob. 30ECh. 12 - Prob. 31ECh. 12 - Prob. 32ECh. 12 - Repeat Exercise 32 if Rw = 1 . Verify your...Ch. 12 - Prob. 34ECh. 12 - Prob. 35ECh. 12 - Prob. 36ECh. 12 - A wattmeter is connected into the circuit of Fig....Ch. 12 - Find the reading of the wattmeter connected in the...Ch. 12 - (a) Find both wattmeter readings in Fig. 12.39 if...Ch. 12 - Circuit values for Fig. 12.40 are , , , , . Find...Ch. 12 - Prob. 41ECh. 12 - Prob. 42ECh. 12 - (a) Is the load represented in Fig. 12.41...Ch. 12 - Prob. 44E
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