Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
End-of-Summer Report
Project overview and purpose
The main focus of Dr. Sy-Bor Wen’s research, Experimental and Theoretical
Analysis for Optical Induced Thermal Energy Transport in Nano-Optical Systems with
Pulsed Light Sources, was on the analysis of the interaction between energy (generated by
various pulsed laser light sources) and a variety of materials. My students will be able to
relate to the some of the aspects in this study because of their familiarity with everyday
application of laser technology. From the laser used in their CD players, to laser surgery
(Lasik and Endovenous Laser Ablation), and security systems, the students are
encountering a wide range of applications of lasers. Biomedicine has proven, in recent
years, to greatly benefit from the application of nanotechnology.
Waves is one of the major units of study in the first year Physics. In this unit the
students are expected to become familiar not only with the general properties of the waves,
but also with sound and light. Light properties and behavior is an important part of this
unit. Due to my E3 RET experience, I would like to modify the study of optics and
approach from a different perspective. Since lasers have become more prevalent in recent
years, the students may benefit from studying the electromagnetic spectrum, wavelength,
frequency, amplitude, reflection, refraction, etc., in the context of lasers. My students will
research and discover the principles of light reflection and refraction using lasers. We will
use laser pointers in a variety of ways in order to design setups that will provide the basis
for the application and explanation of these rules.
Education Standards
The pertinent STAAR and TEKS applicable:
The student will demonstrate an understanding of waves and quantum phenomena.
(P.7) Science concepts. The student knows the characteristics and behavior of
waves. The student is expected to (A) examine and describe oscillatory motion and wave
propagation in various types of media; Supporting Standard (B) investigate and analyze
characteristics of waves, including velocity, frequency, amplitude, and wavelength, and
calculate using the relationship between wave speed, frequency, and wavelength; Readiness
Standard (C) compare characteristics and behaviors of transverse waves, including
electromagnetic waves and the electromagnetic spectrum, and characteristics and behaviors
of longitudinal waves, including sound waves; Supporting Standard (D) investigate
behaviors of waves, including reflection, refraction, diffraction, interference, resonance,
and the Doppler effect; Readiness Standard (E) describe and predict image formation as a
consequence of reflection from a plane mirror and refraction through a thin convex lens;
and Supporting Standard (F) describe the role of wave characteristics and behaviors in
medical and industrial applications. Supporting Standard
(P.8) Science concepts. The student knows simple examples of atomic, nuclear, and
quantum phenomena. The student is expected to (A) describe the photoelectric effect and
the dual nature of light; Readiness Standard (B) compare and explain the emission spectra
Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
produced by various atoms; Supporting Standard (C) describe the significance of massenergy equivalence and apply it in explanations of phenomena such as nuclear stability,
fission, and fusion; and Supporting Standard (D) give examples of applications of atomic
and nuclear phenomena such as radiation therapy, diagnostic imaging, and nuclear power
and examples of applications of quantum phenomena such as digital cameras. Supporting
Standard
The recently revised Science TEKS: (7) Science concepts. The student knows the
characteristics and behavior of waves. The student is expected to: (A) Examine and
describe oscillatory motion and wave propagation in various types of media; (B) Investigate
and analyze characteristics of waves, including velocity, frequency, amplitude, and
wavelength, and calculate using the relationship between wave speed, frequency, and
wavelength; (C) Compare characteristics and behaviors of transverse waves, including
electromagnetic waves and the electromagnetic spectrum, and characteristics and behaviors
of longitudinal waves, including sound waves; (D) Investigate behaviors of waves,
including reflection, refraction, diffraction, interference, resonance, and the Doppler Effect;
(E) Describe and predict image formation as a consequence of reflection from a plane
mirror and refraction through a thin convex lens; and
(F) Describe the role of wave characteristics and behaviors in medical and industrial applications.
Physics principles touched upon by this study
Laser (Light Amplification by Stimulated Emission of Radiation) is a particular
application of light (waves, optics). However, in order to understand some of the
implications and applications of laser, one must draw upon various topics in Physics, such
as energy transfer, optics, nature of light, reflection of light, refraction, diffraction. The
students with which I plan to use this project will be in the Pre-AP Physics, mostly juniors,
with a few seniors. Due to the fact that this is a first-year Physics class, it will be important
to define all the fundamental Physics principles and ideas that apply.
Activities in which the students will engage:
Topics: There will be two main areas of concentration in the project: Energy (heat) transfer
and Optics (a study of ray diagrams for reflection and refraction).
A. The students will be part of designing a set-up that will show heat transfer. The
instructor will be actively involved in this process, as the students will not
possess enough experience in order to safely handle laser pointers. One possible
set up will involve the laser pointers and balloons, in order to test if the laser
beam has sufficient energy to ‘burn’ a small hole in the balloon. It may be
necessary to use a lens in order to further focus the laser beam for added power.
Another possibility would be to light up a match stick with the laser beam. The
transfer of energy for this experiment would have to be sufficient to light up the
match (the flash point of the match tip would have to be pre-determined. These
two experiments will involve cooperative learning, visuals, simulations, demos
and technology integration.
B. A light sensor will be provided, tentatively, in order for the students to compare
the light intensity from a laser beam to the light intensity from the fluorescent
Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
lights in the room. This may have to be performed with a low-power laser, since
the light sensor may not be able to measure the high power beam of some
pointers.
C. Using laser beams, various lenses and mirrors, or a ray box that will be provided
in the classroom, the students will design a set-up to show light refraction and
collimation. In the process, the students will become familiar with beam
convergence and beam divergence. Collimation is another term the students will
have to research. A setup will be required for collimation. A working diagram
(on paper) will be provided by each team. This diagram will have measurements
of angles and distances, focal lengths and other elements that describe reflection
and refraction. The benefit of this experiment would be that the students will
have to research and understand reflection and the principles that govern it,
refraction and the index of refraction. The students will end up ‘discovering’
through experiments or research most of the light and optics laws and principles.
Once the students are familiar with the law of reflection, with Snell’s law, with the ray
diagrams, they will have to begin applying some engineering design to perform their
activities. This will give the instructor the opportunity to address some of the design ideas.
Day 1: A brief introduction of Lasers, definitions and terms. An introduction to laser safety
will be presented (possibly a pre-test). The students must first pass the laser safety test (will
allow two days for preparation for this test).
Day 2: Engineering Design lesson – a brief overview of some of the basic concepts and
principles. The groups will be assigned (three to four students per group).
Day 3: Laser safety test will be administered. One or two laser demonstrations will be
performed. Students will begin their collaboration with their teams. The design problem
will be two-fold: a heat transfer design and a reflection / refraction set up will be required.
They will also be asked to design a set up (using mirrors and lenses) in order to measure the
focal length of a designated lens, as well as a set up to measure laser beam divergence and
convergence. Additionally, the students may be asked to use the light sensor in order to
analyze the laser beam.
Day 4: Student design time – the students will collaborate with their teams to find solutions
and come up with design ideas.
Day 5 and 6: Design trial and re-design time. Realistically, we will need two days for this
phase. Since each group will need some set-up time, we will need approximately 20
minutes for each group to set up and perform their demonstrations.
Day 7: Final design presentations – 15 minutes per team.
Day 8: Post-test – terms, definitions, problems.
Each class will be divided into three groups …
and each group will design one setup and then present it before the class.
Group 1 – Design a set-up that shows total internal reflection. This group will have
one or two laser pointers (different colors), one water bottle and water.
Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
Questions to answer: What is reflection? What is total internal reflection? What
are some applications in technology of total internal reflection?
Group 2 - Design a set-up that shows total internal reflection for optical fiber. This
group will be given a laser pointer and a piece of optical fiber.
Questions to answer: What is Fiber Optics? How does an Optical Fiber transmit
light? What are some applications of Fiber Optic technology?
Group 3 - Design a set-up that shows light transmission through optic fibers, and a
measurement of both the initial intensity as well as the intensity of the light as it is
emitted from the optic fiber.
Questions to answer: How do the two intensity measurements compare? What
accounts for the difference in intensity? Is light “lost” in the optic fiber? What
happens when the optic fiber is bent excessively? What is different between the red
laser and the blue laser?
All Groups Refraction – In groups of three, design two experiments using any materials
available in the lab in order to show refraction. Explain and diagram the law of
refraction (Snell’s Law).
Collimation with two convex lenses. In groups of three, design and diagram an
experimental set up using the ray box available in the lab, or two laser pointers, as
well as two convex lenses. Explain the ray geometry involved.
The student computers (with internet access) are already available to each student. We also
have one or two sets of optical lenses and meter sticks. We will purchase three or four laser
pointers, a light sensor and additional lenses in order to have at least five or six set-ups.
Also, balloons, matchsticks, and other basic Physics lab equipment, will be needed.
Finally, since the Scope and Sequence for the Physics curriculum is prescribed in
our district, my focus will have to be on using this project in order to implement some (or
all) of the requirements in the Scope and Sequence, so that my classes may follow the same
pace as the other Physics in the district.
Summary
The students will become familiar with the basic principles of optics (and be able to
construct ray diagrams) through this project. As a result of this project, the students will
first research and attempt to understand the basic principles of ray optics. The Law of
Reflection and Snell’s Law will become familiar to the students. They should be able to
measure the incident and predict the reflection angles. Also, they should be able to make
calculations of the index of refraction and the critical angle (from Snell’s Law).
The students will also begin to make connections between visible light color and
wavelength (and frequency) of light. They should be able to understand the connection
between the electromagnetic spectrum and energy. Since there is so much emphasis on
energy, the students should be able to understand aspects of heat transfer (energy transfer).
Below is a copy of the Pre- and Post-test.
Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
Laser Challenge Pre-Test
1. What does the acronym LASER stand for?
A. Light Altering through Static Electricity Reduction
B. Light Amplification by the Stimulated Emission of Radiation
C. Light Augmentation by Synchronizing Energy Radiation
D. Light Authentification by Sonar Energy Randomization
2. Visible light can be given off when ____ move between energy levels of an atom.
A. protons
B. photons
C. neutrons
D. electrons
3. Most objects do not produce their own light, but instead _______ light from
other sources, which allows us to see the objects.
A. reflect
B. absorb
C. refract
D. polarize
4. Which type of material filters light so only waves vibrating in one direction can
pass through it?
Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
A.
B.
C.
D.
prism
refractor
polarizer
diffraction grating
5. A lemon appears yellow when white light is shown on it because the lemon ________
yellow light.
A. bends
B. reflects
C. refracts
D. absorbs
6. Which of the following colored cans would absorb the greatest amount of heat?
A. red
B. black
C. white
D. yellow
7. When light passes from air through glass and water, it _________.
A. bends
B. changes color
C. is completely absorbed
D. travels in a straight line
8. If a persons eye focuses the light before it reaches the retina, they would need a
_________ lens.
A. lane
B. convex
C. concave
D. polarize
9. Which of the following is used to play music from a CD?
A. laser light
B. ultraviolet light
C. fluorescent light
D. incandescent light
10. White light is made up of ________.
A. red and green
B. all wavelengths
C. the absence of color
D. blue and yellow
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Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
11. Light rays bounce off of a surface according to the law of __________.
A. Reflection
B. Refraction
C. Diffraction
D. Bending
12. Night vision cameras can 'see in the dark' because they detect
A. ultraviolet
B. microwave
C. infrared
D. gamma
13. Compared with infrared waves, ultraviolet waves ____________.
A. travel slower
B. travel quicker
C. carry less energy
D. carry more energy
14. What determines the color of an object?
A. the light intensity
B. the wavelength of light reflected
C. the wavelength of light absorbed
D. it’s amplitude
15. The lens shown below is a ____ lens and will ____ the light rays.
A. concave; diverge
B. concave; converge
C. convex; diverge
D. convex; converge
16. What body part is most susceptible to damage from lasers?
A. Arms
B. Feet
C. Ears
D. Eyes
17. Select all the fields that use lasers:
A. LASIK eye surgery
B. Welding
C. Video recording
D. Printing
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Marius Maduta, Klein Forest High School, Klein ISD, Houston, TX, Physics, 11th grade,
8 instructional days
18. Thinking about the equation ν = λ·f, wave A is traveling at the same speed as wave B,
but wave A has a longer wavelength than wave B. What can you determine about wave A?
A. It has a higher frequency
B. It has a lower frequency
C. It is moving through a gas
D. It is moving through space
19. What objects would you recommend to focus laser light?
A. Convex lens
B. Concave lens
C. Convex mirror
D. Concave mirror
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