Bombs Away!

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SHPE Foundation
Online SHPE Jr. Member
Activities
TeachEngineering Hands-on
Activity:
*Bombs Away!
TeachEngineering Digital Library:
teachengineering.org
Online SHPE Jr. Member
Curriculum is funded with
generous support from:
SHPE Foundation
Online SHPE Jr. Member Activities
TeachEngineering Digital Library
http://www.teachengineering.org
• The TeachEngineering digital library provides over
1300 free engineering lessons and activities.
• Engineering lessons and activities connect realworld experiences with curricular content already
taught in K-12 classrooms.
• TeachEngineering's comprehensive curricula are
hands-on, inexpensive, and relevant to students'
daily lives.
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Reference Activity on TeachEngineering
• Design and build a device to protect and deliver an egg
to a drop zone.
• Engineering focus:
o Full Engineering Design Process
• Follow all the steps of the engineering design process to build, test,
and redesign a device, optimizing its performance.
• Learning objectives:
o Explain that engineers design and build devices to help people.
o Explain why supplies might need to be dropped from a plane rather
than delivered by a car or truck.
o Identify materials that cushion impact.
o Explain the difference between kinetic and potential energy.
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
• Suggested time: 60 minutes
• Materials
o 6 ft. of yarn
o 3 rubber bands
o a 1 ft. x 1 ft. piece of trash bag
or sheet of waxed paper
o Scissors
o Ruler, yardstick or meter stick
o
o
o
o
o
o
o
1 egg (or plastic egg)
24 in. of masking tape
2 sheets of paper
5 pipe cleaners
5 cotton balls
5 index cards
5 popsicle sticks
o
If using plastic egg: shaving cream and a rock that will fit inside the plastic egg
o
If using a real egg, you might want a few extra just in case of an unsuccessful drop!
o
Note: Feel free to be creative and include additional supplies or remove supplies from
the above list. Alternate or additional supply ideas: foil, grocery bags, plastic straws,
toothpicks or shaving cream. Consider including small rocks that may provide weight
to keep device parts in place. Limit the available supplies for more of a challenge!
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Engineering Connection (Real World Application):
• The safe and accurate delivery of life-sustaining supplies to disaster relief efforts
or military supply locations is an unpredictable real-world design challenge.
• Using limited supplies and an egg to represent perishable supplies, you’ll design,
create and test your device in an effort to investigate problems associated with
supply delivery in remote regions. You’ll mimic the process that engineers use
when designing devices for airdrop supplies.
Airdropped humanitarian supplies
being recovered in Haiti, (2010)
A C-17 military transport airplane drops humanitarian
aid load, dealing with the aftermath of the 2010 Haiti
earthquake.
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Engineering Design Process:
• In this activity, you will act as a real engineer by
following the full engineering design process.
• The engineering design process is a series of steps
that engineers use to guide them as they solve
problems.
• The design process is cyclical, meaning that
engineers repeat the steps as many times as
needed, making improvements along the way.
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Vocabulary
Terms
Definitions
vector
A quantity that has both magnitude and direction. Example vector quantities include velocity, weight and force.
Alternatively, speed and mass are NOT vector quantities and are represented only by their magnitudes.
mass
A measure of how much matter an object contains, or the total number of particles in an object. Mass is not
weight. Weight is the force caused on a mass by gravity.
velocity
A vector quantity whose magnitude is an object's speed and whose direction is in the object's direction of
motion. Velocity is different from speed because velocity describes a direction as well.
acceleration
The rate of change of velocity with respect to time. The measure of how fast the velocity of an object increases or
decreases.
force
Anything that tends to change the state of rest or motion of an object. Force is a vector, represented by two
quantities; its magnitude and direction in space. The magnitude of a force is represented by quantities such as
pounds, tons or Newtons. When a number of forces act simultaneously on an object, the object moves as if acted
on by a single force with a magnitude and direction that are the sum of the applied forces.
energy
potential energy
kinetic energy
impact
The capacity to do work. Several different types of energy include: mechanical, heat, electrical, magnetic,
chemical, nuclear, sound or radiant. For purposes of this activity, we are focused primarily on mechanical
energy since it is the energy of motion.
The energy of a particle or system of particles resulting from position, or condition. Gravitational potential
energy is based on how high off of the ground an object is while other forms of potential energy include springs,
batteries or fuel.
The energy possessed by an object because of its motion.
The striking of one object against another; collision.
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Introduction/Background:
o Have you ever heard of disaster relief supply package drops? Disaster relief
groups and the armed forces must deliver life-sustaining and sometimes
delicate supplies of food and equipment to people in areas very difficult to
reach, often where no nearby roads, trains or airports are located.
o These supplies must reach designated landing areas accurately and intact.
When things do not go as planned, bags of food can burst from the impact,
and sometimes supplies completely miss the target landing areas. (Read a
1994 news article http://community.seattletimes.nwsource.com/archive/?date=19940725&slu
g=1922123 - about emergency food airdrops that landed off target in
Zaire.).
o Your engineering challenge today is to apply what you know about energy
(potential, kinetic, conservation of energy) to attempt to solve this real-life
problem by testing techniques for dropping precious supplies, as
represented by a fragile raw egg, accurately and safely from a designated
height. Let's get started!
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Procedure Overview
• Design a device to protect an egg from breaking when dropped onto the
ground, while also making sure it lands within a designated area.
• (Note: plastic eggs can be used instead of real eggs.)
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Procedure
1. Consider the “disaster” scenario described on the Introduction/Background slide.
The egg is your care package to deliver, and you will need to protect it so that it
doesn’t break when dropping. (If you use a plastic egg, you will need to protect
it from breaking open.) You also need to be able to open and close their
protective device after it is dropped so that the condition of the egg can be
checked. Then, the device can be reclosed and reused at different heights (3, 6,
and 10 feet).
2. You’ll have limited supplies with which to build your device; use supplies that you
have available in your home!
3. Take a few minutes to brainstorm ideas for your device. Using a sheet of paper,
draw out your ideas and select an idea as the first design to build and test.
4. Build and test your device – you can use an egg for sizing purposes.
5. Find a location outside for testing your device. Cut open a trash bag to create a
landing zone. Mark the center of a piece of blank paper with an ‘X.’ Place the Xmarked paper in the center of the trash bag.
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Procedure (continued)
6. Test your device!
a) If you are using a plastic egg, prepare your egg for dropping: add a weight (a rock)
on one side of the plastic egg, and fill the other half with shaving cream. Close the
egg and place it in your protective device.
b) Drop each device from 3 feet above the ground (the entire device should be
above 3 feet) directly above the target. (Note: If you don’t have a way to measure
3 feet, hold the device at the approximate level of your shoulders.)
c) After the egg lands, open your device and check to see if the egg is intact. If it is,
measure and record the distance from the center of the target to where the egg
landed with a ruler.
d) Repeat steps for testing now at 6 feet if your egg did not break dropping from 3
feet. (If your egg broke, redesign your device and test again at 3 feet). (Note: Stand
on a chair or outside bench.)
e) Repeat steps for testing now at 10 feet if your egg did not break at 6 feet. (If your
egg broke, redesign your device and starting the testing process over again). (Note:
stand on the top of a table or short wall.)
f) The best device is one that protects the egg when it’s dropped from 10 feet and
lands on the target. Continue to redesign and test your device until it meets both
objectives. Then you have mastered the challenge!
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Optional Extension
o If there are safe and reasonable locations where you live to drop
your device from a greater height than 10 feet, test your device at
greater heights. See how your egg survives!
o Consider what improvements you could have made to your
device if you weren’t limited by supplies. What other materials from
your home could be used to improve the design?
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Investigating Questions
o What ideas worked the best to protect the egg? Why do you think
they worked? (Think about the transfer of energy. For instance, a
parachute limits acceleration by causing some of the energy to
dissipate due to air having friction with the parachute. This friction
causes an upward force that limits acceleration.)
o Which ideas worked best to improve the accuracy of the device in
landing close to the target? Why did they work?
o Which ideas looked promising in the design phase, but did not
work well? What went wrong? (Perhaps a parachute got caught
underneath the package, etc.)
o How would you improve your designs to better protect the egg?
o How would you improve your designs for more accurate landings?
SHPE Foundation
Online SHPE Jr. Member Activities
Bombs Away!
Assessing Your Understanding!
o Plot the distances away from the target that each egg lands, with
the height on the x-axis and the distance away from the target on
the y-axis. Use different colors to plot results from different versions
of your device, and consider why some designs may have been
more accurate than others. How does the accuracy change as
the height is increased?
o Design Explanations: Explain to a family member or a friend why
your design ensures safe, accurate drops. Make sure to include
how potential energy and kinetic energy in each drop scenario
affect the performance of your device and explain how energy is
transferred when the egg is released until it impacts the ground.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
TeachEngineering Contact Information
• TeachEngineering: http://www.teachengineering.org/
o over 1,300 standards-based engineering lessons and activities
• Carleigh Samson, TeachEngineering Editor
o carleigh.samson@colorado.edu
o 303.492.6950
Questions?
http://www.fws.gov/refuge/Stone_Lakes/FAQ.html/
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