Introduction: Homemade Parachute
The parachute glides slowly down thanks to something known as air resistance (or drag). When air gets under it, the plastic parachute fans out for maximum coverage; this air resistance slows the fall of the object tremendously. The "umbrella" part of a parachute traps air as it opens up. The air is squashed so that it has more pushing power (a higher pressure) than the air around. Since it pushes up, it slows down the parachute and its load to a safe landing speed.
Most parachutes are circular. However, parachutes with special shapes, movable panels, or small openings are often used in displays because they can be steered more accurately.
As well as bringing people gently down to earth, parachutes are also used to break the fall of such things as air-dropped food and medical supplies.
Drop the parachute from a high place such as a chair or side of a staircase. Time how long it takes to reach the ground. Take three measurements and work out the average. Repeat the whole experiment using objects of different weight, threads of different length, and parachutes of different shape. Does a circular parachute, for instance, work better than a square one of the same area? What happens if you cut a small hole in the middle of the parachute? Try using different materials such as cellophane or cotton. Which works best? Try to explain your findings.
- 2-3 Balloons
- Rice or Playdough
- Thin plastic tablecloth (a couple of dollars from a discount store) or a Plastic Grocery Bag
- Measuring tape
- Marking pen
- Clear sticky tape
Step 1: Make the Balloon Weight
Rice filled weight:
1. To easily fill a balloon with rice, place rice in an empty medicine bottle or even an empty soft drink bottle. I use about a 1/3 of a cup of rice.
2. Place the balloon opening over the bottle top, then it’s a simple matter of tipping the bottle upside-down, allowing the twist in the neck of the balloon to open, and the rice will fall from the container into the balloon.
Play dough filled weight:
1. Make a batch of play dough. This recipe will fill about 3-4 balloons but if you want more, just double/triple it.
· 1/4 cup of salt
· 1/2 cup of plain flour
· 1 tablespoon of cream of tartar
· 1/2 cup of water
· 2 teaspoons oil
Add all ingredients to a saucepan and stir of medium heat until it balls up. Remove and knead lightly. Allow to cool.
2. Fill the balloon with play dough until the rounded part of the balloon is full. Then tie a knot in the top. Tips to fill balloon:
Ball up small pieces of play dough and pushed it inside. Use fork/knife/pen to push playdoh in.
3. Decorate with permanent marker (note: after a lot of squishing, the pen can fade but it’s easy to draw it back on again).
Step 2: Time to Make the Parachute
Cut a thin plastic tablecloth into a square with 61 centimeters (24 inches) sides.
Step 3: Fold the Square in Half, and Then in Half Again (so You Have a Smaller Square).
Step 4: You Want to Work on the Corner of the Square That Has the Opening. Measure Two X 13 Centimetres (5 Inches) Lines Out From the Corner to Make a Square.
Step 5: Cut Along the Two Lines and Remove the Excess Material. When You Open It Out, It Should Look a Little Like an Addition Sign.
Cut a piece of tape approximately 5 cm (2 inches) long and bring two sides in together so the edges are parallel. Tape vertically 2.5 cm (1 inch) in from the edge, allowing the other 2.5 cm to hang over so you can fold it over to stick to the other side. Repeat this process on all sides.
Step 7: Check for Openings
You should have small openings in each side of the parachute.
Step 8: Cut Support Strings
Cut two 76 centimeter (30 inch) pieces of string. Measure in 2.5 centimeters (1 inch) on each end and make a small dot with a marker.
Step 9: Attach Strings to Parachute
Use a piece of tape horizontally to stick the string to one corner of the parachute, lining up the dot with the edge. There will be a small piece of string at the top left over. Fold this back over the piece of tape you just lay down, and place another piece of tape over the top (this is to ensure the string doesn’t slip out). Take the end of the piece of string and repeat the process with the next corner along. Then do the same to the other side of the parachute with the other string.
Step 10: Tie the Strings
Pull the string out tight so it’s even and tie a knot, leaving a loop in the end. Repeat on the other side.
Step 11: Tie on the Weight
Cut a short piece of string (about 10 centimeters ), Slip it through the knots and tie another knot around them securing the strings, then tie a knot on the balloon
Step 12: The Parachute Is Finished!
To roll it up ready to fly, hold the top of the chute and use the other hand to squeeze the air out. Take the top of the chute and fold down to where the string part starts. Then roll the chute tightly down into a ball, finishing with wrapping the string around at the end so you’re left with the balloon and a rolled up chute. To throw, hold the ball and chute together in one hand and throw in the air from the ground or from a high place.