San Jose State University
Department of Electrical Engineering
Exam 2
EE 140
Fall 2007
Closed Book, and Notes,
Instructions: There are 10 problems. Interpretation of questions will not be
given during the exam. If you are unsure about the meaning of a que
1) Calculate Zin, in, input return loss and the VSWR in the transmission line of the circuit
below. Frequency of operation is 1 GHz. List also ALL locations of the Vmin in the line.
Zc = 75
7.96 nH
Zo=50
83.3
Length = 2.25
Zin
ZL
Z ind
Z1
25 1
0.33
75 3
j
EE140
Mid-Term 1
Print Name : _
1.
Consider a line charge of linear charge density length L, located along the y-axis as shown.
a.
What is the electric field vector at a point on the x-axis (x,0,0) ?
b.
With V E d , find the electric potential at that loc
EE 140, Spring 2015
Mid-Term 1
Dr. Ray Kwok
Name: (Last, First)_
1. In radio frequency, current practically flow ONLY on the surface of a
conductor. Consider a coaxial cable with a inner conductor of radius a, and
a grounded metal shield of inner radius b
EE140
Mid-Term 1
Dr. Ray Kwok
Print Name : _
1.
A uniformly charged disc with radius R is placed at a distance d above an infinite ground plane. (a) What is the
electric field at a distance z < d above the ground plane along the z-axis?
(b) Using the defi
EE 140
Mid-Term 2
Dr. Ray Kwok
Name: (Last, First) _
1) A 159 MHz LHCP electromagnetic wave is incident normally (along the z-direction) from
air onto a lossless dielectric medium (r = 4, z > 0) such that Eoi(0,0) at the origin is 2 V/m
along the x-direct
EE140
Mid-Term 1
Dr. Ray Kwok
Print Name : _
1.
A spherical dielectric (r1) with radius a and volume charge density = r is enclosed by a dielectric shell (rs) with
outer radius b. The volume charge density of the outer shell is uniform, = .
(a) Find E(r)
EE140
Mid-Term 2
Dr. Ray Kwok
Name: (Last) _ (First) _
1) A laser ( = 500 nm) of parallel polarization is shined onto a 1-cm
o
thick piece of lossless glass (n = 1.5) at an incident angle of 30 .
One observes multiple reflections and transmissions on eith
EE140
Mid-Term 2
Dr. Ray Kwok
Name: (Last) _ (First) _
1) A helicopter is sending a 100W, LHCP 159-GHz millimeter wave to a submarine at an incident angle of 53 degrees.
The incident signal at the water surface has an electric intensity of 2 V/m along the
EE140
Mid-Term 2
Dr. Ray Kwok
Student Name: (Last) _ (First) _
r
1.
[35 pts] A plane wave in air with E = y 5 sin( t 3 z 4 x ) V/m, is incident upon the planar surface of a
dielectric material with r = 2.25, occupying the half-space x > 0. Write the full
EE142
Mid-Term 2
Dr. Ray Kwok
Name: (Last) _ (First) _
1. Glass isosceles triangular prisms shown in Figure are used in optical instruments.
Assuming r = 4 for glass, calculate the percentage of the unpolarized, normally
incident light power reflected bac
EE 140, Spring 2014
Mid-Term 1
Dr. Ray Kwok
Name: _
1. A spherical dielectric shell (r = 3), with inner radius 2 m and
outer radius 4 m, is filled with a charge density = 5 r.
(a) Find E(r) everywhere.
(b) Sketch E(r) and label all the points.
(c) What is
EE 140, Spring 2014
Final Exam
Dr. Ray Kwok
Name: _
1. An unpolarized but focused beam of light ( = 700 nm) is shined onto a 2-cm thick piece of
o
glass (n = 1.43) at an angle of 55 from normal. Calculate the relative power (in dB, relative
to the inciden
EE 142, Fall 09
Sample Mid-Term 1
Dr. Ray Kwok
Name: (print) _
1)
Find the direction of the current in the resistor R shown in Figure at each the
following steps:
(a) at the instant the switch is closed,
(b) after the switch has been closed for several mi
Mid-term 1
Fall 10
SJSU EE142
Electromagnetic Fields & Waves
Instructor: Dr. Ray Kwok
1) [30 pts] A RHCP electromagnetic wave is propagating in the -x direction in a lossless
medium of r = 4 and r = 9 at a frequency of 1 GHz. The electric field amplitude
EE142, Fall 2011
Mid-Term 1
Dr. Ray Kwok
Name: _
1) Find the direction of the current in the resistor R shown in Figure at each the following steps: (circle the
correct answers)
(a) at the instant the switch is closed, (left
left,
left right or none?)
(b)
1) Calculate Zin, in, input return loss and the VSWR in the transmission line of the circuit
below. Frequency of operation is 1 GHz. List also ALL locations of the Vmin in the line.
Zc = 75
7.96 nH
Zo=50
83.3
Length = 2.25
Zin=?
ZL=25
Mid-Term 2
Fall 2009
EE142
Dr. Ray Kwok
1.
An unpolarized but focused beam of light ( = 700 nm) is shined onto a 2-cm thick
piece of glass (n = 1.43) at an angle of 55o from normal. Calculate the relative
power (in dB, relative to the incident power) of t
Sample Mid-Term 2
EE142
Dr. Ray Kwok
Sample Mid-Term 2 - Dr. Ray Kwok
1.
An unpolarized but focused beam of light ( = 700 nm) is shined onto a 2-cm thick
piece of glass (n = 1.43) at an angle of 55o from normal. Calculate the relative
power (in dB, relati
EE142, Spring 2012
Mid-Term 1
Dr. Ray Kwok
Name: _
1) A electromagnetic plane wave is propagation in air with its electric field given as:
r
E = x 20 sin(t 2 z + 3 y ) V/m. What is the frequency and wavelength of this wave? What
is the corresponding magne
Sample Mid-Term 2
Fall 2009
EE142
Dr. Ray Kwok
1.
A parallel-polarized plane wave is incident from air onto a
dielectric medium with r = 9 at the Brewster angle. What is
the refraction angle?
tan B =
n2
9
=
=3
n1
1
B = 71.6o
B + t = 90o
t = 90o B = 18.
EE140
Mid-Term 2
Dr. Ray Kwok
Student Name: (Last) _ (First) _
1.
[35pts] Glass isosceles triangular prisms shown in Figure are used in optical instruments. Assuming r = 4 for glass,
calculate the normally incident light power reflected back (in dB) by th
EE140
Mid-Term 1
Dr. Ray Kwok
Print Name : _
1.
A long coaxial cable of radius a is carrying a non-uniform current density
J r 2 z (into the page). The outer
shield is a grounded conductor and a dielectric r is filled between b and c. B = 0 in the grounde
Chap'ie? E
Section i=3: Eraveiing Waves
Probﬁem 1.1 A 4-111-12 sound wave traveling in the x—direction in air was observed
to have a differential pressure p(x._ z) = 5 "ﬁlm2 at x = 0 and r z 25 ,us. If the reference
phase or" phat) is 42", ﬁnd a complete
CHAPTER 1
1.1. Given the vectors M = 10ax + 4ay 8az and N = 8ax + 7ay 2az , nd:
a) a unit vector in the direction of M + 2N.
M + 2N = 10ax 4ay + 8az + 16ax + 14ay 4az = (26, 10, 4)
Thus
a=
(26, 10, 4)
= (0.92, 0.36, 0.14)
|(26, 10, 4)|
b) the magnitude of
EE140
1.
Review Electrostatics
Dr. Ray Kwok
Consider two point charges (+Q, -Q) located along the x-axis as shown.
a. What is the electric potential at point P(2a,0)? (Note: there is no charge at point P.)
b. From this potential, derive an equation for th
EE140
Mid-Term 1
Dr. Ray Kwok
Name : _
1)
A wire, carries a time-varying current I1, is located at a distance d away from a rectangular loop made of
N turns of copper wire of dimensions L and w. The loop is moving away from the line at a velocity v at an
EE 140
Mid-Term 2
Dr. Ray Kwok
Name: (Last, First) _
1) A 159 MHz LHCP electromagnetic wave is incident normally (along the z-direction) from
air onto a lossless dielectric medium (r = 4, z > 0) such that Eoi(0,0) at the origin is 2 V/m
along the x-direct
EE 140
Mid-Term 2
Dr. Ray Kwok
Name: (Last, First) _
1) A laser ( = 500 nm) of perpendicular polarization
is shined onto a 1-cm thick piece of lossless glass
o
One
(n = 1.5) at an incident angle of 30 .
observes multiple reflections and transmissions on
e
EE 140, Spring 2014
Mid-Term 1
Dr. Ray Kwok
Name: _
1. A spherical dielectric shell (r = 3), with inner radius 2 m and
outer radius 4 m, is filled with a charge density = 5 r.
(a) Find E(r) everywhere.
(b) Sketch E(r) and label all the points.
(c) What is
EE 140, Spring 2015
Mid-Term 1
Dr. Ray Kwok
Name: (Last, First)_
1. A rectangular coil with N turns and total resistance R, (length L < 1, and width W < 1) as
shown in figure. The coil moves into a uniform magnetic field B with constant velocity v.
Plot t