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# When doing the egg drop for the parachute I was wondering if we should cut a hole in the top or not? Answered

Me and  my brother are doing an egg drop for his boy scouts and for the parachute we are using a paper plate. But I don't know whether to cut a hole in the top to make it go faster or to leave it whole.

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Speaking as a Cub leader, this is a science/technology/creativity challenge - don't ask to be spoon-fed the "right" answers, work it out for yourselves.

Build parachutes with various sizes of hole, with different lengths of cord, and use them to drop a golf ball or egg-sized stone. Time their falls.

When you get as slow a time as you can, switch to a real egg, and then see if you need to add padding of any kind.

I used parachutes quite often as we were kicked out of planes and helicopters on a regular base.
To give you something to work with:
The distance from the bottom of the chute to the weight hanging on it should be 1.5 to 2 times longer than the diameter of the chute.
Otherwise it will tend to swing uncontrolled in all directions.
The hole seems to make everything worse but it has a purpose:
1. It gives stablility during the decent by creating a strong air stream that prevents the chute from swinging.
2. It stablilises the chute itself so it stays "inflated"
Funny thing is that despite the hole the chute actually comes down slower if the hole diameter is correct (sorry no formula for it at hand:( ).

Since you use paper it might be hard to get a nice round shape that looks like a real parachut, but here is an alternative:
Create a square "plate" of paper.
Add a round hole in the center that is quite small (you can always make it bigger if the chiute tubles too much).
Now to get the thing flying also add a rim of paper around the plate - make it look like a square frisbee.
Glue enough lines on it while keeping the top flat - this will help to keep the flat shape.
Make the lines twice as long as what you measure from one corner of the plate to the opposite site - diagonally measured of course.
Try not to use sticky tape but really use glue as otherwise the next step will be hard.
Crumble the chute, flatten it, crumble it again - you do this to make the paper flexible.
If you don't you have a hard time using the chute;)
As an alternative to paper I suggest using Tyvek - the stuff these white full body dresses are made off that protect you from paint, dust and so on.
The stuff is the best material I found so far for homemade chutes.
If is flexible, incredibly strong and lets ait go through which helps to further stabilise the chute.
No real parachute is made from material that won't let air go through ;)

1. Cutting the hole will make it more stable.

2. Cutting the hole will make it fall faster

3. You should make a slot and make the plate into a shallow cone for better stability.

4. The bigger the plate the better.

5 A raw egg dropped or tossed from a second story window onto grass will not crack - try it!