# Help me with my Physics!

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I need to construct some sort of object around a raw egg to prevent it from breaking.

Starting at a height of 1m and withstanding several drops until it is finally dropped from the bleachers in the football field.

The catch is, I can only use 5 sheets of computer paper and a meter of tape. Any ideas?

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Think of springs?

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Surround the egg with oragami boxes?

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Make a cone and put the egg inside. Although I think that'll only work once. Think crumple zones like a car hood.

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To prevent the egg from breaking, you want to reduce the amount of force it experiences on impact. When the egg reaches the ground, it is going to stop, one way or another, and if it is stopped suddenly, by a large force, it will probably break in the process.

There are two ways to do this: Firstly, you can minimize the force necessary to stop the egg in the first place, by counteracting the accelerating force of gravity during the entire descent, i.e., a parachute.

Secondly, you can counteract the acceleration of the egg upon reaching the ground by applying a smaller force over a longer period of time, i.e., a cushioning effect. The momentum and energy the egg will gain from falling a particular distance will be the same, but rather than stopping the egg in a very short time with a large force, you can provide the same impulse and counteract the same momentum with a longer time spent decelerating and a smaller force applied over that time.

That's the difference between punching a pillow and punching a brick wall. The pillow gives, it lets your fist sink into it and decelerate at a lesser rate, rather than a brick wall that stops your fast in a fraction of a second with a much larger reactive force.

If you combine both of these ideas, you can not only slow the descent, but control it, as a parachute should assure that your contraption lands bottom-side down. If you can control which way your egg contraption will land, then you can place your egg at the top, and allow it to pass through several crash sheets of paper before hitting the ground.

I might try something like a long tube of paper, suspended from a paper parachute, with the egg taped to the top of the tube and shredded paper filling the tube to the brim. A tube just wide enough to fit the egg will provide additional resistance to slow it, besides making the most effective use of your limited materials, and if the tape is strong enough to suspend the tube while the whole apparatus is falling with a somewhat slowed descent, then it shouldn't break free from the tape until you actually hit ground, and at this point, the egg can slide into the tube and into all the shredded paper (I'm thinking anywhere from half a metre to a metre long), which ought to be enough to slow it down without braeking it from any height.

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i remember doing this in eighth grade and being the only person to get an a

we used milk cartons, and i filled mine with oil

for some reason im thinking maybe constructing a gyroscope shaped thing with the tape and paper and suspending the egg in the middle would be pretty good

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wtf

we need to have homework like this in physics

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Just a note, I remember doing something similar in middle school - the parachute idea does not work well because it is such a short height - you need a large height in order for the parachute to be effective.

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I need to construct some sort of object around a raw egg to prevent it from breaking.

Starting at a height of 1m and withstanding several drops until it is finally dropped from the bleachers in the football field.

The catch is, I can only use 5 sheets of computer paper and a meter of tape. Any ideas?

I know nothing about physics so I'm just making this up.

Tape two sheets of the computer paper together lengthwise, SECURELY(no air in between, use one piece of thick tape along the entire edge).

Tape another two sheets together on top of each other, only use tape that is rolled onto itself in a wide circle that you can stick your hand through. Use several of these makeshift double sided tape to tape the two pieces of paper together. Finally, do the same thing with the last piece of paper and the egg, and tape the long makeshift piece of paper to the two insulated pieces of paper, and tape it all to the little paper package around the egg.

I have NO idea how much tape that would use, though.

EDIT: Bahamut has a good point.

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I remember some guy accomplishing this by noting that, in our assignment prompt, it was never stated that the egg needed to be in freefall.

So he just taped the egg to a long and narrow length of paper, and manually lowered the paper along with the egg. So my advice is, check the exact wording of the assignment.

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I remember some guy accomplishing this by noting that, in our assignment prompt, it was never stated that the egg needed to be in freefall.

So he just taped the egg to a long and narrow length of paper, and manually lowered the paper along with the egg. So my advice is, check the exact wording of the assignment.

There's a future lawyer, but not an engineer or physicist.

Re: the parachute. I've never done this or seen it done, although of course I've heard of the infamous egg-drop before. I was thinking ahead to the drop off the gym bleachers. It seems that the parachute ought to slow it down a little, but more important is assuring that the contraption lands right-side-up when you drop it from a greater height. Otherwise you have to account for the possibility of impact occuring from any side, and with the limited materials, that makes this a major challenge.

How would you do it Bahamut?

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Not sure, but the parachute comment was just a note - if one was to observe the differential equation, you would hardly shorten the velocity given the time frame the object is in air. I also remember when I did a similar assignment that parachutes were useless and were just laughable to watch in their futility.

So yeah, I would think of trying to cushion the egg and secure it.

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Figured I'd at least post a picture of what I was talking about.

The placement of the egg towards the front of the cone pretty well ensures it will fall tip first. On impact the energy is dissipated by the crupling of the nose, which basically acts like a spring. Or at least that's my take on it, I'm not a mechanical engineer though...

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Figured I'd at least post a picture of what I was talking about.

The placement of the egg towards the front of the cone pretty well ensures it will fall tip first. On impact the energy is dissipated by the crupling of the nose, which basically acts like a spring. Or at least that's my take on it, I'm not a mechanical engineer though...

I think you're onto something there. You could also pre-fold the lower half of the cone so that it would be more pre-disposed to crumple, depending on how stiff the material was to begin with. Given that it's computer paper, that may not be necessary, but since there are several sheets, maybe it would be.

We don't want the cone to stop dead and the egg to crack while trying to keep moving and squeeze through the tapering tunnel. The crumpling is crucial.

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we got to do model rockets and solar powered cars in our class.

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Figured I'd at least post a picture of what I was talking about.

The placement of the egg towards the front of the cone pretty well ensures it will fall tip first. On impact the energy is dissipated by the crupling of the nose, which basically acts like a spring. Or at least that's my take on it, I'm not a mechanical engineer though...

I think you're onto something there. You could also pre-fold the lower half of the cone so that it would be more pre-disposed to crumple, depending on how stiff the material was to begin with. Given that it's computer paper, that may not be necessary, but since there are several sheets, maybe it would be.

We don't want the cone to stop dead and the egg to crack while trying to keep moving and squeeze through the tapering tunnel. The crumpling is crucial.

Or even better, stuff the bottom of the cone with paper.

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Probably the best thing to do at this point is to build some of these different ideas and see what happens. Plus I agree that the parachute idea is a bad one from both the diff. eqn. and from my experience in 5th grade at "Astro Camp" .

Edit: Gotta be careful about stuffing stuff in the nose. If the nose is either too stiff or not stiff enough it won't dissipate enough energy. Stuffing the nose would have a similar effect to making it stiffer, which could put you past the sweet spot. Similarly it could put you into the sweet spot. At this point you've just got to try stuff.

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when u stuff the paper in the bottom of the cone do not pack it tight. its a cushion, that means precrumple then uncrumple the paper.

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Figured I'd at least post a picture of what I was talking about.

The placement of the egg towards the front of the cone pretty well ensures it will fall tip first. On impact the energy is dissipated by the crupling of the nose, which basically acts like a spring. Or at least that's my take on it, I'm not a mechanical engineer though...

I think you're onto something there. You could also pre-fold the lower half of the cone so that it would be more pre-disposed to crumple, depending on how stiff the material was to begin with. Given that it's computer paper, that may not be necessary, but since there are several sheets, maybe it would be.

We don't want the cone to stop dead and the egg to crack while trying to keep moving and squeeze through the tapering tunnel. The crumpling is crucial.

Or even better, stuff the bottom of the cone with paper.

But if you use a cone, the egg will only be able to fall so far before it'll be squeezed too much. If you put the egg higher up, the centre of mass will likely cause the cone to flip over upside down. For that reason, I prefer the crumple-zone idea. You make better use of the full stopping distance.

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I seriously doubt that there'd be that much sideways pressure on the egg from the cone, but what do I know? I'm a chemistry major.

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So maybe the egg should be taped tightly to the bottom of the cone also?

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my little pseudo-gyroscope idea, by the way, has "roll cage" in mind

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Parachutes not allowed. I had thought of a cone as well, but it needs to last through several drops.

I thought of making one with little paper protrusions all along the outside kind of making it look like a spiked ball.

Don't think the paper would be strong enough to make it work though.

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Could you do two differnt cones, and use the tape to suspend the egg between the halves? That way, no matter which side it was on, it would have the same amount of crumple zone

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My dad had a good idea - make a sort of sphere around the egg, supported by pillars from the egg to the sphere.

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