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Student reflection activities:
Prompt students to think about the following and record their responses
on Activity sheet: Reflection (RSS-5)
in their journals.
- What would a visible or infrared image of a coral reef look like?
- How do our own sensory systems sense things without physically touching
them?
- If we fly over a coastal environment in an attempt to sense visible
and infrared radiation, what factors will need to be considered when
flying over the coastal environment?
Assessment:
Ideas for math lesson enhancements:
- Students learn power of ten (scientific) notation and
compare the power of ten associated with different types of EM radiation.
- Students use the relationship: wave speed = frequency
X wavelength (v = f l) to solve
for one of the variables when the other two are given.
- Students determine the energy of EM radiation of a certain
frequency by using the relationship: energy of EM radiation = Planck's
constant X frequency (E = h f). (E = hc/l is also suitable where c = speed of EM radiation in a vacuum
and l = wavelength)
Related National Education Math Standards:
- numbers and operations
(http://standards.nctm.org/document/chapter6/numb.htm)
- algebra (http://standards.nctm.org/document/chapter6/alg.htm)
- measurement
(http://standards.nctm.org/document/chapter6/meas.htm)
Ideas for geography lesson enhancements:
- Students identify different land forms, such as volcanoes,
tropical forests, ice packs, water, etc., or places on earth while viewing
remote sensing images.
Related National Education Geography Standards:
Ideas for technology lesson enhancements:
- Students learn to consider EM radiation as a form of
energy and investigate processes involving energy transformations to
and from EM radiation such as those found in the harnessing of solar
power.
- Students learn that power is the rate at which energy
is converted from one form to another.
Related National Education Science Technology Standards:
- The
Designed World (#17) (http://www.iteawww.org/TAA/Listing.htm) Energy and Power Technologies
Activity Sheet: Invisible light observations (RSS-1)
answer key
Name: ___________________
1. Draw or describe your observations of the Invisible Light demonstration.
- ANSWER: The prism separated
white light coming from the room lights or from sunlight into the various
colors of the visible spectrum. IR radiation was also separated as evidenced
by the increased temperature at the location just beyond the color red
in the resulting spectrum.
2. The light that passed through the prism was from the room lights or from
light coming into the room from outside. What do you think the demonstration
tells you about what that light is made up of?
ANSWER:
- White light is actually made
up of all colors or another way to say it is that if you combine light
of all colors you get white light.
- The sun gives off more than
just light visible to our eyes and that IR energy is in the direction
of red, not blue.
Activity Sheet: How does remote sensing work? (RSS-2)
answer key
Name: ___________________
1. Define the following terms:
ANSWER:
·
Wavelength - The wavelength is
the length of one wave cycle, which can be measured as the distance between
successive wave crests.
- Frequency - Frequency is usually
measured as the number of cycles or vibrations each second. One cycle/second
is called 1 Hertz (Hz).
2. Complete the following table. In the comparison section,
compare the wavelength of a typical wave of that type to one meter. (For
example: The distance across your fingernail is about 1/100th
of a meter.)
ANSWER:
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Type of
EM radiation
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Comparison of wavelength of type to 1 meter
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Examples/uses of this type
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Radio waves
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Any where from about 1 meter to over 10,000 kilometers
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Radio communications such as AM or FM
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Microwaves
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Some where in the range of about a 1/10th of a
millimeter to a meter
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Used in microwave ovens and RADAR
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Infrared
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Somewhere on the order of a micrometer (1 millionth of a
meter) to 1/10th of a millimeter
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Heat that you feel without touching is infrared radiation.
Heat lamps for keeping food warm is called thermal IR. Near and
mid IR can't be felt or seen by humans but are very important in
remote sensing, e.g. plants reflect strongly at various near and
mid IR and this helps in detecting and identifying various types
of vegetation.
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Visible (light)
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Very narrow range of wavelengths that we can detect with
our eyes. In the range of 400-700 nanometers. One nanometer is one
billionth of a meter.
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The light that we see.
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Ultraviolet
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Somewhere on the order of one ten millionth of a meter to
one billionth of a meter
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Form of radiation responsible for sunburn and integral component
of energy changes occurring during photosynthesis in plants
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X-rays
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Somewhere on the order of one billionth of a meter to one
one-hundred billionth of a meter.
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Used for medical imaging of dense tissue and utilized in
gaining insight into the structure of matter in X-ray diffraction
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Gamma rays
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Any wavelengths smaller than those associated with x-rays
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This is the form of EM Radiation most commonly associated
with nuclear radiation. Other nuclear radiation involves the emission
of particles.
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Activity sheet: Nature of light (RSS-3)
answer key
Name: ___________________
1. What did you observe on the underside of the white paper when you placed
construction paper of different colors underneath it?
ANSWER:
- The white
paper will have a hue the same color as the construction paper beneath
it.
2. What did you observe when the color of the filter was the same as the color
of the object?
ANSWER:
- The object
will look the same color as the filter. It looks the same color as it
naturally does; the light it reflects is the same color that the filter
allows to pass. There is no change. In this demo only a small portion
of the EM spectrum is used. The objects have a particular color because
they are absorbing all other colors except the one they are reflecting.
We are separating out only a small portion by using a filter that only
transmits one portion.
3. What did you observe when the color of the filter was different than the
color of the object?
ANSWER:
- The object
will look a different color than its natural color; the object may look
quite dark, perhaps even black. In this demo only a small portion of
the EM spectrum is used. The objects have a particular color because
they are absorbing all other colors except the one they are reflecting.
If the filter doesn't allow that particular wavelength to pass then
no light from the object can make it to your eyes and the object looks
black.
4. Based on your experiences with the invisible light demonstration, construction
paper investigation, and the color reflected from colored objects demonstration,
how would you explain where the light comes from when you look at someone
wearing a multi-colored shirt? How do the colors you see on the shirt
end up getting to your eyes?
ANSWER:
- The room lights
or sunlight provide a source of all visible wavelengths. When looking
at the shirt, the colors we see have been reflected by the shirt. Those
we cannot see have been absorbed by it. Each part of the shirt has a
particular color because different dyes absorb all wavelengths but one.
That one is reflected and our eyes detect it.
5. Which types of EM radiation would be most useful for locating coral
reefs?
ANSWER:
- We can learn
about coral reefs from what we can see (visible EM radiation) and what
we cannot see (infrared EM radiation).
Activity sheet: Reflection
(RSS-5) answer key
Name: ___________________
1. What would a visible or infrared image of a
coral reef look like?
ANSWER:
ANSWER:
- How high to fly
- How fast to fly
- What wavelengths to sense
- How many times to pass over
- Weather conditions (clouds, winds, etc)
- Time of day
- Where to take off and land
Teacher notes to accompany Construction Paper investigation:
White paper will reflect all colors (visible wavelengths). Orange paper
absorbs all colors (visible wavelengths) except orange. Students are likely
to have a difficult time visualizing this phenomenon and may not "believe"
that something is actually being reflected by the orange paper. The white
paper is used in this demonstration to "prove" to the students
that light is actually being reflected by the orange paper. In reality
it proves that white paper reflects orange light but experienced teachers
have used this demonstration successfully.
It is important that you explain the purpose of the white paper and then
help them understand that many objects appear the color they do because
of the light they reflect.
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