School of Materials Science & Engineering
Fall 2016/Bill Knowlton
MSE 410/ECE 340
Electrical Properties of Materials
Problem Set 1
Reminder From Syllabus:
Problem Set Format Checklist:
At the top of the page, include your name, problem set number, course name & number, and
date.
Submitted problem sets must be legible, neat and decipherable.
Show all work. Complete work means step-by-step.
Multiple page problem sets must be stabled with problems kept in sequential order.
Multiple page problem sets must be stabled except for ABET questions.
Answers must be circled/boxed.
If the answer has units, include the units as they are required.
All graphs must be thoroughly labeled, have axis titles and units, figure captions, and detailed
explanations. Include comments on trends you observe and what you want your audience to take
away from the graph. Using legends, arrows, and text will facilitate trends you want to point out.
Using color does not help if you print your problem set in black and white. Extra credit many
times is given for exceptional graphs with thoughtful and thorough explanations.
All software program code must be thoroughly documented/commented and follow the above
criteria. Include units. If unit conversions are being performed, the manner in which they are
performed (e.g., dimensional analysis) need to be complete.
"ABET Problems" - These problems are to be handed in separately and follow the criteria above.
ABET problems with multiple pages should not be stapled. ABET problems will be assessed
more thoroughly than other problems relative to completeness, correctness, legibility, neatness
and decipherability, so extra care should be taken when answering these questions.
Grading – The TA/grader will provide a cursory review of your solution and provide a grade based
on being able to follow and understand your solution. The grade will be based on the final solution,
the completeness and validity of the path to the solution, and the Problem Set Format Checklist.
If the grader cannot decipher your solution, you will be graded accordingly. Ultimately, you are
responsible for understanding the solution to each problem.
Citing - Remember to cite your references using references that have been peer-reviewed. (yes,
need to do for this assignment as well)
Note: Besides problem 1, the other problems are review problems for which answers can be found in your
ENGR 245 Introduction to Materials Science & Engineering, first and second semesters of physics courses,
and first semester chemistry course.
1. Ethics: [ABET question]
Program Outcome H. The broad education necessary to understand the impact of engineering solutions in a
global, economic, environmental, and societal context.
Go to my Courses Website at:
http://coen.boisestate.edu/bknowlton/course-information/82-2/
a. You will find a section called “Scientific and Professional Misconduct”. Read the articles about the
physicist Jan Hendrik Schön and one of the stem cell researchers, either Woo Suk Hwang or Haruko
Obokata, and the predicament they are in. Comment on what might have gone wrong and/or where they
went wrong in their careers that led them to where they are today.
b. Read through the sections “Information on: Academic Honesty” and “Dismissal & Student Code of
Conduct” for Boise State. Comment on why Boise State takes this so seriously. Relate your comments
to your comments in part a.
c. Explain how might your reflection and discussion with respect to part a and b affect your undergraduate
career and career beyond bachelorette degree?
2. Waves and Wave Motion
a. Define the following for a wave in a sentence or two for each: Wavelength, Frequency, Velocity
b. Look up and write down the equations that relates i) wavelength, frequency, velocity and ii) energy and
wavelength. Define all variables.
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School of Materials Science & Engineering
Fall 2016/Bill Knowlton
MSE 410/ECE 340
Electrical Properties of Materials
c. What is the difference between a transverse wave and a longitudinal wave? Use an illustrative
(drawing) example that you have created to aid your explanation. You may use phonons (wave packet
of crystalline lattice vibrations) in your illustration. That is, you may use examples of transverse
phonons and longitudinal phonons.
d. Using a graph that you have created with a mathematical program (not Excel) to help you, explain the
following:
i. Constructive interference
ii. Destructive interference
3. Electromagnetic spectrum: Calculate the range of frequencies or wavelengths (in meters) and energies
(in eV) for parts a-g using mathematical expressions for each (which you should show). Show and define
the mathematical expressions you use and the variables in the mathematical function you use in your
calculations and cite the references you used using a peer reviewed source. Hint: use problem 2b to help
you.
a. Radio and TV?
b. Microwaves?
c. Infrared?
d. Visible light?
e. Ultraviolet?
f. X-Rays?
g. Gamma Rays?
h. Using a mathematical program (not Excel), plot the electromagnetic (i.e. photon) energy (y-axis) from 0
eV to 10 eV as a function of wavelength (x-axis, units of nanometer) using the mathematical function you
used in the first part of this problem. On your plot, label thoroughly and show the energy and wavelength
ranges of the visible spectrum with lines that bound the region. Comment on whether or not you think
that the energy range of the visible spectrum is easier to remember in units of eV or units of Joules.
4. Bonding: The Lennard-Jones potential is one way to mathematically describe the bonding interaction
between two atoms. It provides the equilibrium bond length, ro, and the equilibrium bond energy, Eo.
a. Look up and write down the equation for the Lennard-Jones potential. Define all the variables. Cite the
reference where you obtained the Lennard-Jones potential.
b. Using a mathematical program (not Excel), plot the Leonard-Jones potential so that you obtain a graph
somewhat (but not exactly) similar to figure 1.10 in your book using the units of eV for energy and
nanometers for interatomic distance (Note: unit conversions are necessary). Label your plot thoroughly
including units, labeling ro, and labeling Eo. Note: pay attention to the magnitude of energy and length in
nanometers. If the values you obtain do not make physically sense, then you probably made a mistake
(usually with unit conversion).
c. For r > ro, why does your plot of energy never reach 0 or a positive value?
d. At a given E=f(r), describe the mathematical process to step by step find the bond energy and the bond
length of your plot. Mathematically, how could you ensure that ro was a minimum and not a maximum?
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School of Materials Science & Engineering
Fall 2016/Bill Knowlton
MSE 410/ECE 340
Electrical Properties of Materials
5. Crystallography:: Showing all steps in your work including drawing a cubic unit cell, determine the Miller
indices for the following shown in the cubic unit cells. Show all work and label thoroughly (e.g., axes,
origin, unit lengths). Show all steps. You may use a table to show your steps.
a.
b.
6. Crystallography: In your crystallography notes in table 1-3, one of the 14 space lattices is incorrect.
Which one is incorrect and why?
7. Crystallography: List the two components necessary to describe a crystal structure.
8. Defects: The formation energy of vacancies in Cu, Ag and Au is about 1 eV (p. 262 Kelly & Groves).
Calculate the equilibrium concentration of vacancies at 300 K in Cu. You will need to know the density and
AMU of the elements. What type of behavior does the plot of vacancy concentration versus 1/T exhibit?
9. Defects: On the last page of the “Bulk Defects in Materials Notes”, cracks and pits are shown in GaN.
What is the rotational symmetry of the pits? Explain why you think the symmetry exists.
10. Defects: Name and describe two of each type of defect listed in the following
a. Point defect
b. Line defect
c. Planar defect
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