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 8, Problem 70E
A dc motor can be modeled as a series RL circuit (though with the addition of a back emf voltage, which we will ignore in this problem), where rotational speed is proportional to the current flowing in the circuit. A motor with R = 10 Ω and L = 20 mH has a source voltage of 2.5 V that is suddenly increased to 5 V. How long would it take for the motor to reach 95 percent of full speed?
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For the series RL circuit shown in the figure below, answer the following questions and justify your answer.If the current is kept constant, does the coil have inductance?If the current is kept constant, does the coil affect the current value?Can the reverse emf ever be greater than the battery emf?
The figure below depicts the winding of an electric motor. It has a resistance of R = 15.3
and an inductance of L = 20.6 mH (watch the multiplier!!!).
110 V
60 Hz.
www
R
Motor
Connecting this motor to an alternating source of 110 Volts, and a frequency of 60 Hertz
(shown in the figure), your task is finding the current = V/Z Amperes that flows throughout
the winding of the motor. Recall that your reference is the incoming voltage V.
Extra Problem: Calculate the frequency of oscillations for the square-wave generator
circuit shown in the following Figure from Floyd's textbook. Also plot the output and
capacitor voltage waveforms clearly showing the amplitudes and time-period. Assume R1
= 40 k2, R2 = 100 k2, R3 = 86 k2, C = 0.01 µF and Op Amp supply voltage is +/- 15V.
R1
Vc
o Vout
R2
R3
Chapter 8 Solutions
Loose Leaf for Engineering Circuit Analysis Format: Loose-leaf
Ch. 8.1 - For the circuit in Fig. 8.2, what value of...Ch. 8.1 - Noting carefully how the circuit changes once the...Ch. 8.2 - In a source-free series RC circuit, find the...Ch. 8.3 - Prob. 4PCh. 8.3 - Prob. 5PCh. 8.4 - Prob. 6PCh. 8.4 - Prob. 7PCh. 8.4 - Prob. 8PCh. 8.5 - Evaluate each of the following at t = 0.8: (a)...Ch. 8.6 - For the circuit of Fig. 8.37, find vc(t) at t...
Ch. 8.7 - Prob. 11PCh. 8.7 - The voltage source 60 40u(t) V is in series with...Ch. 8.7 - Prob. 13PCh. 8.8 - Prob. 14PCh. 8.8 - Prob. 15PCh. 8 - A source-free RC circuit has R = 4 k and C = 22 F,...Ch. 8 - A source-free RC circuit has v(0) = 12 V and R =...Ch. 8 - The resistor in the circuit of Fig. 8.51 has been...Ch. 8 - Prob. 4ECh. 8 - Prob. 5ECh. 8 - Prob. 6ECh. 8 - Prob. 7ECh. 8 - Prob. 8ECh. 8 - Prob. 9ECh. 8 - The switch in Fig. 8.56 has been closed for a long...Ch. 8 - For the circuit in Fig. 8.56, find (a) the total...Ch. 8 - Design a capacitor-based circuit that can achieve...Ch. 8 - (a) Graph the function f (t) = 10e2t over the...Ch. 8 - The current i(t) flowing through a 1 k resistor is...Ch. 8 - Radiocarbon dating has a similar exponential time...Ch. 8 - For the circuit of Fig. 8.4, compute the time...Ch. 8 - Design a circuit which will produce a current of 1...Ch. 8 - Prob. 18ECh. 8 - Prob. 19ECh. 8 - Referring to the circuit shown in Fig. 8.11,...Ch. 8 - Prob. 21ECh. 8 - With the assumption that the switch in the circuit...Ch. 8 - The switch in Fig. 8.57 has been closed since...Ch. 8 - The switch in the circuit of Fig. 8.58 has been...Ch. 8 - Assuming the switch initially has been open for a...Ch. 8 - (a) Obtain an expression for v(t), the voltage...Ch. 8 - For the circuit of Fig. 8.61, determine ix, iL,...Ch. 8 - Prob. 28ECh. 8 - Prob. 29ECh. 8 - Prob. 30ECh. 8 - Prob. 31ECh. 8 - (a) Obtain an expression for vx as labeled in the...Ch. 8 - Prob. 33ECh. 8 - Prob. 34ECh. 8 - Prob. 35ECh. 8 - Prob. 36ECh. 8 - Prob. 37ECh. 8 - The switch in Fig. 8.70 is moved from A to B at t...Ch. 8 - Prob. 39ECh. 8 - Prob. 40ECh. 8 - Evaluate the following functions at t = 1, 0, and...Ch. 8 - Prob. 42ECh. 8 - Prob. 43ECh. 8 - Prob. 44ECh. 8 - You can use MATLAB to represent the unit-step...Ch. 8 - With reference to the circuit depicted in Fig....Ch. 8 - For the circuit given in Fig. 8.75, (a) determine...Ch. 8 - Prob. 48ECh. 8 - Prob. 49ECh. 8 - You build a portable solar charging circuit...Ch. 8 - The switch in the circuit of Fig. 8.78 has been...Ch. 8 - The switch in the circuit of Fig. 8.78 has been...Ch. 8 - Prob. 53ECh. 8 - Prob. 54ECh. 8 - Prob. 55ECh. 8 - For the circuit represented in Fig. 8.82, (a)...Ch. 8 - Prob. 58ECh. 8 - Prob. 59ECh. 8 - For the circuit given in Fig. 8.85, (a) determine...Ch. 8 - The circuit depicted in Fig. 8.86 contains two...Ch. 8 - Prob. 62ECh. 8 - Prob. 63ECh. 8 - A series RL circuit has a voltage that steps from...Ch. 8 - For the two-source circuit of Fig. 8.89, note that...Ch. 8 - (a) Obtain an expression for iL as labeled in Fig....Ch. 8 - Obtain an expression for i(t) as labeled in the...Ch. 8 - Obtain an expression for i1 as indicated in Fig....Ch. 8 - Plot the current i(t) in Fig. 8.93 if (a) R = 10 ;...Ch. 8 - A dc motor can be modeled as a series RL circuit...Ch. 8 - Prob. 71ECh. 8 - Prob. 72ECh. 8 - A series RC sequentially switched circuit has R =...Ch. 8 - Refer to the circuit of Fig. 8.95, which contains...Ch. 8 - In the circuit of Fig. 8.95, a 3 mF capacitor is...Ch. 8 - Prob. 78E
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