In this activity, our main purpose is for you to see the forces of flight through a parachute and how it works. We eventually want you to create your own parachute and base your design on using different materials. Ultimately, your task is to determine the best material and design to make it work best. Before Christmas, we will test all designs. Each group will provide an informal presentation to the class on why they chose the design they did and why they thought their materials would work best. May the best future engineer win!
In this activity, your primary purpose is to design a parachute for a miniature action figure. This figure will be provided and will remain constant for all groups. Your objective is two-fold:
What material do you think will make the best parachute and
What design can you create to make this parachute suspend in the air the longest?
When people skydive, they jump out of an airplane from a very high altitude. They fly through the air and release a parachute to help them fall safely to the ground. Hopefully, the parachute slows down the skydiver's fall so that they can land on the ground at a safe speed.
How does this happen?
As the skydiver is free-falling, the force of gravity will pull the skydiver and their parachute towards the earth. The problem is, the force with which gravity acts can make the object fall extremely fast!
The purpose of a parachute is to slow the skydiver down. This happens due to air resistance, or drag force. The air pushes the parachute back up and creates a force opposing gravity. Thankfully, this will slow the skydiver down. As the skydiver falls slowly to the earth, these "push and pull" forces should balance one another.
This activity will integrate your understanding of the words:
Thrust
Lift
Weight
Drag
But how do these words affect the overall operation of a parachute? Ultimately, what are you trying to increase? Do you want to increase the thrust? Is it necessary to improve the lift? Your weight will be consistent, so should we worry about drag? Let's look at the video to your right.
As future engineers, we hope you have now discovered that the most important aspect of this design will be your work with drag. This science project will test your ability to create a parachute that will slow down the speed of the fall.
You need to determine what material will work best, what size will be most effective, and what shape will achieve the best results.
Every group needs to design prototypes, test them, and work together to achieve the best design for your final product.
After this activity, students should be able to:
Determine ways for designing a parachute that falls gradually.
Use different testing scenarios to determine which type of material works best.
Understand the term air resistance and how it creates drag, which plays an important role in flight.
How does a parachute really work? What kind of applications would we use parachutes for?
If we increase the diameter of the parachute, would this influence drag? Does the overall size of the parachute really matter?
If we talk about air resistance, how can we create a stronger drag force?
Do you really think drag force affects how a parachute works?
Does the type of material make a big difference in the performance of a parachute?
Attached strings connect the parachute to an object or person. Does the length of these strings really matter?
Does the actual shape of your design, influence how the parachute descends to the ground?
A parachute is an umbrella-shaped device. It is generally made of a light fabric and used especially for making a safe jump from aircraft. Never forget that due to the resistance of air, a drag force acting on a the parachute, will slow down its motion. If we didn't have air resistance, or drag, objects would gain speed and crash, harming whatever is attached as they hit the ground. Parachutes use a large canopy to increase air resistance. This gives a slow fall and a soft landing. The question remains, what is the most effective type of canopy in terms of design and material?
This leads us to talk about VARIABLES in science experiments. Variables are simply factors that influence the outcome of an experiment. These are super important and worth a good understanding. Following the rules around these makes the experiment valid and trustworthy.
There are three types of variables:
Independent Variables: These we can change and make our experiment a true test. In the case of the parachute, the length of the attached string and the different types of materials used are good examples. These are items that can make our experiment testable.
Dependent Variables: This is the part of a science experiment that is measured and observed. We see how the independent variables above made a difference. In the case of our parachute experiment, we will be measuring the time it takes for the parachute to land. We will observe which design creates more drag and air resistance.
Controlled Variables: These are the things we can keep consistent for everyone. It is the factors we can keep the same for each experiment and testing situation. In the case of the parachute experiment, we will:
limit the maximum size of the parachute to be 4 square feet
determine a specific height for parachute release
provide the same parachute attachment for everyone
provide the same person to drop each parachute
Define your purpose
As a group, research and brainstorm various parachute designs. In your research and brainstorming, determine design shapes and material suggestions. (Day One)
After you agree on a design, determine the materials you will need to make it. Bring in ample material, since you will want to construct several prototypes.
Test your original design and record the time.
Make another prototype similar to the one you just created, but make changes.
Test the new parachute and record your findings.
Repeat this until you are happy with your design. Ask yourself:
What type of material was the best material?
What didn't work so well?
What changes can we suggest to make our design better?
When you are finished, submit your design and get ready to compete with other groups.
The group with the parachute taking the longest time to land will be crowned champions.
Rubric for our Parachute Experiment.pdf
Credit: Some ideas and suggestions for this activity have been retrieved from the following sites: