| Project 2: Parachutes and Force Directions |
| Background One of the main reasons parachutes are used in any kind of situation is to slow down an object that is either free-falling or moving at such a great speed that normal brakes cannot be used. The purpose of doing so is to reduce the force with which the object will strike the ground. Consider the parachutist in the image below. He is gliding through the air at a speed that will not kill him when he lands on the ground. Some force is pulling him down, and some force is acting to keep him from falling too fast. In this project, you will investigate how parachutes overcome two forces: the down-pulling force that causes objects to free fall and the counter force that saves lives. You will do so by simulating skydiving with a weight and homemade parachutes. | |
Getting started with this experiment.
Now you are ready to get started. Remember the question you are trying to answer with this experiment as well as the variables and constants needed for this experiment to be controlled.
SCIENTIFIC INVESTIGATION QUESTION
What effect does parachute size have on the time it takes for a parachute to reach the ground?
A sample set of materials and procedures are provided for you below. If you would like to substitute some materials or change the procedure, that is OK as long as you keep records of what you do and explain it on your lab report in the Materials and/or Procedure section.
If you do not have the materials to conduct your own experiment, please contact your instructor. Remember, your teacher’s contact information can be found on the syllabus near the top of the page.
SUGGESTED MATERIALS
- 1 large plastic garbage bag
- 3 weights which are the same (i.e. washers, toy figures, screws/bolts)
- 7 m of regular cotton string (10 mm or less in diameter)
- tape or hole punch (for attaching strings to the parachute)
- digital stopwatch (on cell phone or online stopwatch)
- measuring tape or ruler
Safety
Make sure to observe proper laboratory behavior while conducting the lab. Take precautions while dropping objects from heights. Make sure no one is below you during the experiment, and be sure the parachutes can be safely retrieved. Do not climb buildings or other structures without authorization.
SUGGESTED PROCEDURE
Follow the steps to complete the investigation. Use the lab handout to record the results of your investigation.
- Construct three parachutes out of the garbage bag. It is recommended that you use a hexagon shape for your parachutes (right), but the size of each parachute must be different.
- Measure the width of each canopy and record in Table 1: Parachute Canopy Size. Use the following example (see image on right) on how to measure the size of the parachute.
- Use string and/or tape to attach a weight to each parachute. Use the same weight for each parachute.
- Find an appropriate testing size where you can drop the parachutes from a height where you can measure the time it takes for it to fall and wind/breeze is minimal. When dropping the parachute, keep the drop height the same. It is recommended that you drop your parachute from at least 6 feet. (Use a ladder, step-stool, raised deck.) Practice safety when dropping the parachute!
- Drop the smallest-sized parachute and record the time it took the parachute to drop. Record your observations in Table 2: Parachute Drop Time. Repeat at least two more times (at least 3 total trials).
- Drop the middle-sized parachute following Step 5.
- Drop the largest-sized parachute following Step 5.
