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You've probably heard that what goes up must come down. Because of the gravity on earth, things fall very quickly! Sometimes, though, we want things to fall slowly. For example, firefighters called smokejumpers jump out of aircrafts to put out forest fires. They need to fall slowly to the ground so they don't break their legs. They use parachutes to slow down their fall. To learn more about gravity and parachutes, read the explanation and follow the links below.
Make your own toy parachute by collecting the materials and following the instructions!
Experiments are dangerous, but scientists are always safe!
have an adult help you collect the materials and conduct the experiment.
|→||large plastic bag (strong material is best)|
|→||long piece of string|
|→||small, lightweight object|
Cut a large circle out of the plastic bag. To draw a good
circle, choose a spot near the center of the bag. Use your ruler to
measure out lines of equal length coming from the center of the circle;
connect the points at the ends of the lines to make your circle.
The better you draw your circle, the better your parachute will be.
2) Use the protractor to divide the circle into six equal parts. Each part will have an angle of 60°. It will look like a pizza with six slices, but don't eat it! Make small holes at the ends of the lines that separate the six parts of the circle. There should be six holes total.3) Cut the string into six equal pieces. Each piece should be about 3 times the length of your circle's radius (the radius is the distance between the center of the circle and the edge of the circle). So, if the radius of your circle is one foot long, then your string pieces should each be three feet long.
4) Tape the six strings to the six holes. For a fashionable parachute, use clear tape.(picture)
5) Tie the loose ends of the strings to your object. If your object is a teddy bear like ours, please be gentle; bears are sensitive animals.(picture)
6) Now, drop the object off of something high or throw it up in the air.
Yippeeeeeeeee! Bears can fly!
Now that you have seen how this works, experiment with your parachute by changing:
→the length, number, or material of the string
→the size or weight of the object
→creating slits or holes in the parachute (this will make the parachute fall faster, but it will also help it balance).
→the size or material of the parachute
When you throw an object into the air, it falls right down again, right? This is because of a force known as gravity. What is gravity?Sir Isaac Newton discovered that objects (things that have mass) are drawn toward each other. Very large objects, like the Earth, have more mass, so smaller things (like people) are pulled toward the Earth. This pull, or force, is called gravity. That's what keeps us from flying off into space.
When an object is dropped, it rushes to the Earth at a very fast speed. Parachutes, as you can observe through experiments, help slow the object down. How do they do this?
Parachutes trap air; the air then pushes upward against the parachute, while gravity continues to pull the parachute downward. The effect is a slower fall for the object that is attached to the parachute. We call this effect air resistance or drag.
Has a great animation of a skydiver and explains some of the physics behind the parachuteLeonardo De Vinci
Tells more about this famous inventor's life, including his early designs for a parachuteParachute history
Explains the history of the parachuteElephant and Feather
Explains air resistance and how it slows falling objects.Gravity
Students explain what gravity is and how it works.
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