Those Wacky Invisible Waves
Overview
Physical Science
Through this activity, students will recognize that we are surrounded
by different electromagnetic waves and that those waves have varying
strengths and lengths. They will experiment with how effectively those
waves can be manipulated (blocked, diminished, and redirected).
Finally, they will consider the ways in which humans depend on
electromagnetic waves for communication.
Please note the descriptions and the steps for the experiment refer
to “remote-controlled devices.” Ideally, the devices can be remotecontrolled cars — enough for each group to have one. Physical space
might pose a challenge, too, but students should be able to complete
their experiments within a standard classroom if a more open space is
not possible. Some alternatives for remote-controlled devices could be:
• iPod speakers/docking stations (or other portable music devices)
• DVD players (if the school’s DVD players can be moved)
• TVs (if the school’s TVs can be moved)
• Ask students to bring in remote-controlled devices and the
remote controls. Explain they should not be too big and difficult
to bring to class.
Space Science
Time Required
45-50 minutes
Standards
Addressed
Light interacts with matter
by transmission (including
refraction), absorption,
or scattering (including
reflection). To see an object,
light from that object—
emitted by or scattered from
it—must enter the eye.
One final note, if equipping the student groups with enough remotecontrolled devices is too difficult, use only one device (ideally a car)
and conduct the experiment as a class — each student group can be
in charge of wrapping the remote control with a specific material.
Objectives
In the course of completing this lesson, students should:
• Recognize that there are different types of electromagnetic
waves
• Recognize some of the ways in which the waves influence
everyday life
• Detect some of the ways that influence the ability for different
waves to travel
Those Wacky Invisible Waves
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Background & Connection to the ISS
We are surrounded by electromagnetic waves. The sun emits many
of them, but we also rely on certain human-made waves, such as
radio waves, X-rays, and even low- frequency waves that electric
outlets emit. They enable us to beam television signals, communicate
with one another on cell phones,
get online with wifi connections,
heat food with microwaves, etc. Understanding the electromagnetic
spectrum is difficult, but it starts with understanding there are waves
that make up the spectrum. In general, electromagnetic radiation is
classified by wavelength into radio, microwave, infrared, the visible
spectrum we perceive as visible light, ultraviolet, X-rays, and gamma
rays. (Sound waves are not electromagnetic radiation.) Typically,
remote-controlled cars and airplanes are controlled by radio waves
and televisions are controlled by infrared waves. Infrared waves
require line of site whereas radio waves do not. This lesson will help
students grasp the concept of electromagnetic waves.
The ISS is also surrounded by electromagnetic waves, but much of its
research takes advantage of its vantage point. The orbital position of
the ISS gives it unique remote sensing capabilities, using equipment
that can detect and measure a wide range of waves that make
up the electromagnetic spectrum. The International Space Station
Agricultural Camera (ISSAC) is one example. Its prime purpose is to
collect multispectral data supporting agricultural activities and related
research in the Upper Midwest of the United States. ISSAC collects
information in the visible and near-infrared wavelengths (3 bands) at a
nominal ground resolution of 20 meters per pixel.
Materials
Required
Handouts [at the end of this
document]
All materials tie in with the
experiment, so there needs
to be enough to equip each
group:
•Remote-controlled devices
•Masking tape
•Cotton balls
•Aluminum foil
•Plastic wrap
•Wax paper
•Rubber glove
Another interesting piece of hardware is the Hyperspectral Imager
for
the Coastal Ocean (HICO). It can take images of the ocean that
were previously impossible. If pictures are taken around large
bodies of water, it is noticeable that light can reflect off of the water.
However, from its vantage point, HICO can compensate for different
light conditions, weather conditions, coastal conditions, and water
conditions to produce images with incredible depth ... literally! It
records reflected waves of light (including those that are near infrared)
and coverts them into images — some of which could be humancreated catastrophes, such as when millions of gallons of oil spill into
an ocean. Yet the images help predict the rate and the direction of the
spilled oil. That information helps those on Earth target their cleanup
efforts and identify priorities for minimizing damages.
Researchers continue to explore ways to better understand and
capture the waves of the electromagnetic spectrum. Part of the
research includes understanding better what affects how waves travel
— much like the focus of this lesson plan!
Those Wacky Invisible Waves
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Activity Steps
1. Survey students and ask if any of them have satellite television. Then ask if there are ever instances
where the picture gets bit-mapped (delayed, choppy squares of color) or disappears completely
(whether briefly or for a long time). Have students describe what it’s like. Finally, ask them why they
think it happens. (Open that up to everyone, even if they don’t have satellite TV at home.) If it doesn’t
come up, ask students if they notice any times when it tends to happen. (They might say during
storms.) Guide the conversation so students think about how the picture arrives to the home — at a
minimum, that a satellite sends a signal down to the dish on the roof.
2. Ask students if the signals being beamed down from satellites can be seen. (Of course, not!) So …
what are those signals?
3. Watch the multimedia definition in the Learn the Lingo section of the CASIS Academy website for
“electromagnetic spectrum.” [www.casisacademy.org]. Afterwards, have two students explain what
the electromagnetic spectrum is. Based on the definition, one student tries to explain its meaning, and
the other student adds to and/or amends the explanation. Listen to the definition again and identify
any other additions or clarifications students would like to make. If necessary, guide students to
recognize the spectrum is made up of different rays that travel in waves and the waves vary greatly in
size.
4. Begin the transition into the experiment by having students brainstorm human-created waves (like
satellite television). Spend a few minutes doing a rapid-fire list of examples. If students don’t think
of it on their own, ask them how scientists on the ISS communicate with people on Earth. Likely
examples students will identify are cell phone signals, Internet wifi signals, radio, X-rays, microwaves
in ovens, radar, remote-controlled devices for electronics, etc. (If students don’t think of remotecontrolled devices on their own, try to guide them to that.)
5. Bring the conversation back to remote-controlled devices (if necessary), and ask if the waves can be
blocked or weakened. Let students know that’s what they’ll be experimenting with today.
6. Use the group sizes and set-up students are familiar with for experiments. Of course, much of it will
have to do with the number of remote-controlled devices and physical space available for students to
complete their experiments.
Those Wacky Invisible Waves
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Controlling the Remote Control (aka Doing the Wave & Messing with the Wave)
Below are the steps for the student experiment [included in the handout]. There are also notes included
for teachers:
1.Run a quick check of the remote-controlled device. Does it function as it’s supposed to without
any interference? If not, check the batteries.
2.Experiment with the strength of the signal by changing the distance between the remote control
and the device it is supposed to activate. Point the remote control in different directions. Try to
establish its range and abilities. Have students record what they observe.
3.Using cotton balls and masking tape, wrap the remote control in cotton — making sure it is
completely covered but still operational. Move to different locations, trying to activate the device.
Does it work? Does it depend on distance and direction? How does it compare to the performance
of the remote control without any cotton covering it? Have students record what they observe. If
the device doesn’t work at all, slowly remove the covering until it functions. What happens?
4.Repeat Step 3, using aluminum foil, plastic wrap, wax paper, and rubber glove.
5.Overall, what happens when the remote control is covered? Are there differences between the
materials that were used? Why are some materials more effective than others in blocking the radio
or infrared waves?
6.Based on their experiences and observations, have students identify a question they would like
to pursue. For example, why was aluminum so effective in blocking the signals/waves? What
materials are satellite dishes made of? Why do storms sometimes interfere with signals and other
times they don’t? What makes a wave stronger or weaker? What happens when waves cross one
another?
Extensions & Modifications
•In class and/or at home, have students research their questions raised during the lesson and report
their findings in writing and/or orally. Challenge them to create a script that presents their findings like
the multimedia glossary explanation of “electromagnetic spectrum” in the Learn the Lingo section of
the CASIS Academy website. [www.casisacademy.org] Additionally, challenge students to list at least
one additional question they developed while researching the answers to their questions.
•Encourage students to create a similar experiment at home with a remote control device, involving
other members of the family. They should ask others to try to predict the outcome of the different
materials used to wrap the remote control.
•A creative cross-curricular activity can be to establish a premise that waves, like those that carry
satellite TV signals, existed during a historic period that students are studying in social studies.
Somehow the waves have been trapped all of these years (instead of being deflected or absorbed).
Now with the discovery of those trapped waves, we can get a glimpse of what it was like then. What
would those trapped waves show us?
Those Wacky Invisible Waves
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Those Wacky Invisible Waves
Background
We are surrounded by waves — electromagnetic waves. The sun emits many of them, but we also rely
on certain human-made waves, such as radio waves, X-rays, and even low-frequency waves that electric
outlets emit. They enable us to beam television signals, communicate with one another on cell phones,
get online with wifi connections, heat food with microwaves, etc.
Of course, the International Space Station is also surrounded by waves — many of them don’t even reach
the Earth, especially those that we can’t see without specialized equipment. Some of the most specialized
of the specialized equipment is on the ISS. From the ISS’s unique position in Earth’s orbit, humans are
able to see things that would be extremely difficult to view here on the ground.
For example, the Hyperspectral Imager for the Coastal Ocean (HICO) can take images of the ocean that
were previously impossible. It records reflected waves of light (including those that are near infrared that
can’t normally be seen) and coverts them into images that can reveal what it looks like below the surface
all the way to the ocean floor in many places.
Many of these devices operate by utilizing the electromagnetic spectrum. In this activity, you will explore
this form of energy that behaves as a wave.
Experiment: Controlling the Remote Control (aka Doing the Wave & Messing with the Wave)
1.Run a quick check of the remote-controlled device. Does it function as it’s supposed to without any
interference? (If not, check the batteries.)
2.Experiment with the strength of the signal by changing the distance between the remote control
and the device it is supposed to activate. Point the remote control in different directions. Try to
establish its range and abilities. Record what you observe.
3.Using cotton balls and masking tape, wrap the remote control in cotton — making sure it is
completely covered but operational. Move to different locations, trying to activate the device. In the
chart below, record what you observe:
Those
Those
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Wacky
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Waves[HO-1A]
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Cotton
Aluminum
Plastic Wrap
Wax Paper
Glove
Does the signal
still work?
Does the signal
change with
distance?
Does the signal
change with
direction?
4.If the device doesn’t work at all, slowly remove the covering until it functions. What happens?
5.Repeat Step 3, using aluminum foil, plastic wrap, wax paper, and rubber glove. Fill in the rest of
the table above.
Overall, what happens?
Are there differences between the materials that were used?
Why are some materials more effective than others in blocking the radio waves?
What is a question that would be interesting to pursue as a follow-up to this experiment?
Those
Those
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Wacky
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Invisible
Waves
Waves[HO-1A]
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