EE 2800 A
Homework #17  20 points
Due: Monday, November 6, 2014
1. In the following circuit, the initial voltage across the capacitor is vc (0) = 50V.
a. Find the voltage across the capacitor, vc, as a function of time. (5 pts.)
b. Find the time (in seco
EE 2800 A
Homework #20  20 points Due: Monday, December 1, 2014
1. For the following circuit:
R
+
C
Vt)
Vout (t)
L
a. Find the transfer function H000) = V3. (4 pts)
b. Find (H(iw) if R=100 0, L=4 mH, and C=1 (3 pts)
c. Sketch (HGw) using the values g
EE 2800 A
Homework #18  20 points Due: Friday, November 14, 2014
1. In the following circuit, the switch has been open for a long time and is closed at time t=0.
a. What is the initial current, i(0+), through the inductor? (2 pts)
b. Find the current, i(
EE 2800 A
Homework #19 ~ 20 points Due: Wednesday, November 19, 2014
1. For the following highpass filter:
C
vin(t) R vom(t)
3. Find the transfer function HUw), in terms of w, R, and C. (3 pts)
b. If R=500 0, find the value of C needed for a Vzpower freq
EE 2800 A
Homework #16 ~ 20 points Due: Monday, November 3, 2014
Under load, the motor opporates with a slip of 4%
and has rotational losses of 2 kW.
3. Determine the rated speed of of the motor in rpm. (1 pt.)
b. Determine the power factor of the motor
EE 2800
Homework #15  20 points Due: Wednesday, October 29, 2014
1. A threephase AC motor is rated at 1180 rpm.
3. Calculate the synchronous speed ifthe motor has 6 poles and operates at 60 Hz. (3 pts)
b. Calculate the slip for the motor (3 pts)
c. Calc
EE 2800 A
Homework #14  20 points Due: Friday, October 24, 2014
1. Find the effective turns ratio in of ideal transformer needed to step up a 120'Vrms voltage to
5000 Vrms. (3 pts)
2. Find the effective turns ratio of an ideal transformer needed to step
EE 2800 A
Homework #13  20 points Due: Monday, October 20, 2014
1. A balanced, Yconnected, threephase load has an impedance of ZLN = 200 +j50 Q for each
phase. Assuming the phase sequence is positive, there is no line impedance, and that Vab is the
refe
EE 2800 A
Homework #12  20 points
Due: Wednesday, October 15, 2014
Va= 25A 0V
a. The line~toneutral voltages, V3; and Vcn, at the load. (
3 pts)
b. The linetolrine voltages, Vab, V1, and V0,. (Spts)
c. The line currents, IaA; lbs, and lcc. (5 pts)
d.
EE2800 A
Homework #11  20 points Due: Monday, October 6, 2014
1. Find and sketch the Norton equivalent of the following circuit. (8 pts)
0 l a
25V
0 so
2. What should the load, RL, be in the following circuit so that maximum power will be
delivered to th
EE2800 A
Homework #9  20 points Due: Wednesday, October 1, 2014
1. An arc welder draws 70 Alms at a power factor of 0.7 lagging from a 240VrmS 60Hz power line.
a. Find the complex power consumed by the welder. (2 pts)
b. Find the value of the ideal capa
EE2800 A
Homework #8  20 points Due: Monday, September 29, 2014
1. Write a set of mesh current equations for the following and express the answer in a matrix. The
control variables should not appear in your matrix. You do not need to soive the equations.
EE2800 A
Homework #7  20 points Due: Friday, Sept. 26, 2014
1. Write the following as a single impedance. Assume that w=500 rad/sec. (6 pts)
1H
10!
002 F 2 (I 0.001 F
2. Find the steadystate current i(t) in the following circuit if w=100 rad/sec. (Hint:
EE2800 A
Homework #6  20 points Due: Wednesday, Sept. 24, 2014
1. Solve the steadystate current i1 in the following circuit. (6 pts)
50
4A
0
2. Find the RMS value of each of the following signals. (2 pts each)
a. i(t) = 24 sin(1000t 60) A
v (volts)
t
EE 2800 A
Homework #5  20 points Due: Monday, September 15, 2014
1. Simplify the following to a single equivalent component. (6 pts)
50 uF
60 11F
120 uF
70 11F 20 FF
b
2. If the current through a ZmF capacitor is i(t) = 6e"4t A , find the voltage across
EE 2800 A
Homework #4 ~ 20 points Due: Friday, September 12, 2014
1. Set up node voltage equations for the following circuit in matrix form. Do not solve. (8 pts.)
2. Set up the mesh current equations for the following circuit in matrix form. Do not so
EE 2800 A
Homework #1  20 points Due: Friday, August 28, 2014
1. Calculate the resistance of a 10meter section of silver wire which has a diameter of 1.5 mm.
(5 pts).
2. Use KCL to determine the values of each of the unknown currents in the figure shown.
EE 2800 A
Homework #2  20 points Due: Friday, September 5, 2014
1. Reduce the network shown to a single equivalent resistance by combining resistances in series
and parallel. (6 pts)
209
200
409
409 29
109
2. A source supplies 4 A to the parallel combina
EE 2800 A
Homework #3  20 points Due: Monday, September 8, 2014
1. Determine i1, i2, i3, v1, and vz for the following circuit. (10 pts)
l
10V
0 m
100 1cm
2. Find the current, i, in the following circuit. Hint: think voltage divider! (4 pts)
12 V
3. Sol
EE 2800 A
Homework #20  20 points
Due: Monday, December 1, 2014
1. For the following circuit:
R
+
vs(t)
C
+

vout (t)
L

.
a.
Find the transfer function () =
b.
Find () if R=100 , L=4 mH, and C=1 mF. (3 pts)
c.
Sketch () using the values given in
EE 2800 A
Homework #19  20 points
Due: Wednesday, November 19, 2014
1. For the following highpass filter:
C
+
vin(t)
+

R
vout(t)

a. Find the transfer function H(j), in terms of , R, and C. (3 pts)
b. If R=500 , find the value of C needed for a power
EE 2800 A
Homework #21  20 points
1.
Due: Wednesday, December 10, 2014
For the ideal OpAmp circuit given: (5 pts.)
a. Find the value of R2 needed for the output V0 to be amplified by a factor of 20 if R1=2 k.
b. Is the output inverted?
R2
R1

+

vs
+
V
EE 2800 A
Homework #18  20 points
Due: Friday, November 14, 2014
1. In the following circuit, the switch has been open for a long time and is closed at time t=0.
a. What is the initial current, i(0+), through the inductor? (2 pts)
b. Find the current, i(
EE 2800 A
Homework #17  20 points
Due: Monday, November 6, 2014
1. In the following circuit, the initial voltage across the capacitor is vc (0) = 50V.
a. Find the voltage across the capacitor, vc, as a function of time. (5 pts.)
b. Find the time (in seco
EE 2800 A
Homework #14  20 points
Due: Friday, October 24, 2014
1. Find the effective turns ratio in of ideal transformer needed to step up a 120Vrms voltage to
5000 Vrms. (3 pts)
2. Find the effective turns ratio of an ideal transformer needed to step
EE 2800 A
Homework #16  20 points
Due: Monday, November 3, 2014
1. The following is a nameplate from a motor. Identify each of the following. (7 pts)
(a)
(e)
(b)
(f)
(c)
(g)
(d)
2. A certain 6pole, 440Vrms, 60Hz, threephase, deltaconnected induction
EE 2800
Homework #15  20 points
Due: Wednesday, October 29, 2014
1. A threephase AC motor is rated at 1180 rpm.
a. Calculate the synchronous speed if the motor has 6 poles and operates at 60 Hz. (3 pts)
b. Calculate the slip for the motor. (3 pts)
c. Ca
EE 2800 A
Homework #12  20 points
Due: Wednesday, October 15, 2014
1. Each phase of a connected load consists of a 50 resistance in parallel with a 75mH
inductance. Find the impedance of an equivalent Yconnected load. Assume 60Hz operation.
(4 pts)