egg drop project?!?!?!?!?

Question

I’m not really sure what to do on it!! So far the materials I have are a popcorn box, bubble rap and packing peanuts. What else could I use and how do I put it together???

Answer 1

As my Dad always said, it's not the drop that will kill you, it's the sudden stop at the end!

You can estimate the kinetic energy of the egg at the moment the bottom of the popcorn box impacts the ground. This energy must be absorbed in such a way the maximum deceleration of the egg is below the "break and make a mess" threshold. Have you experimented to determine what that deceleration is?

I built one of these contraptions in college and the egg survived a 30 foot drop. The way I conceived it is that the box acts as a "crumple zone" to absorb some of the impact and start slowing the egg without adding any more pressure to the egg. I created two chambers. The lower one was empty and there was a diaphram beween the two chambers. I put attached a weight in the bottom to ensure that the bottom hit first.
In the upper chamber, the egg was in bubble wrap and suspended from the top of the box using rubber bands. I also had rubber bands down the sides. The dynamics are that when the box strikes the ground it decellerates the whole thing as the lower chamber crumples. The egg also decelerates against the rubber bands which can be modeled as a spring. Yo can test rubber bands to find what the k is for the assembly. The rubber bands on the side dampen the bounce of the egg to keep it in the box. You get an acceleration of the egg where m*a=k*x
and .5*m*v^2=.5*k*x^2, where x is the elongation of the rubber bands.
Since the crumple zone will help slow the system, there will be energy lost so .5*m*v^2 wil be less than m*g*h

I didn't use packing peanuts. I guess those could be used to help slow the egg in the upper chamber.

I have also seen the use of a sponge at the bottom of the box to provide a longer duration, and therefore, lower deceleration.

good luck.

j