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Physics students drop more eggs

In Egg Drop II, the rules were tightened and stakes were raised. . .

by Sara Walsh on January 29, 2007

The physics students recently completed Egg Drop II.  Egg Drop I allowed the students to use any materials they wished in order to make a contraption that would an egg to survive a 5 meter drop.  For Egg Drop II, they were given:  two pieces of paper, about 30. cm of duct tape, and one class period.  They worked with a partner to try to create an apparatus that would allow the egg to survive another vicious drop.

Before they began, students calculated the momentum of an unaided egg, dropping from the same height.  They then calculated the impulse of that egg and the force at which it hit.  Since momentum is always conserved (therefore the impulse is the same) their goal of the egg drop was to simply alter the impulse.  Since impulse=F*t, their goal was to lengthen the time, therefore reducing the force.  Some groups used the parachute of wing theory, while others used a "front end collapsing" system, similar to what is used in automobiles.  

Most the eggs survived the first 5 meter drop, partly because of the nice bed of snow they landed on, therefore increasing the time.  We were able to see a direct relationship between the amount of time they fell and the force with which they hit.  It appeared as though the amount of force the egg could withstand was around 0.60 N.  

To test the eggs again, we dropped them from a height of 3.0 meters, but this time onto concrete.  All the eggs finally met their end, partially due to wet, weak, and overused safety systems.