Course Project: High School Physics AP II Falling Egg (Not what you thought)

I. Intro

Date: 05/23/2019

This was not the falling egg you thought. Here were the rules:

1. The egg must not crack.
2. The egg should land at the bull’s eye as close as possible.
3. The eggshell must touch the ground.

Since we were done with our AP Physics II exams, so we had plenty of time to do the projects. The first two were very easy. There were countless pieces of information you can find on the internet. But the third one means that you must somehow make the egg move in the mechanism.

II. Design

A. Design Flow

1. First, the egg has to survive the shock, this can be done with a scrub sponge.
2. but the shell has to touch the ground, so the mechanism needs something to transfer the egg to the ground from the sponge.
3. It’s purely mechanical. Even though a timed release mechanism is probable if the timer set is larger than the falling time, it’s just hard to make one. And how do you connect the timer to the release mechanism with a kitchen alarm?
4. So it needs to be triggered when it touches the ground.
5. The motion is vertical, and the motion of ground relative to the egg is up. I can push a stick so that its lowest point is below the entire mechanism, when the stick hits the ground, it will be pushed up.
6. Mean while, the stick can pull and open a gate, release the egg to the sponge. Then the egg will roll down from the sponge to the ground.

It’s perfect.

B. Final Design

The following picture is the scratch of the final design.

1. Black line: outer case
2. Green line: gate. It’s a piece of moderately hard and moderately flexible plastic card. It’s hard enough to hold the egg and flexible enough to curve.
3. Blue line: Two blue lines form a guide. There is another guide on another plate, which is mirrored with this one. They hold the gate in place and make sure the gate can slide out by the pulling stick.
4. Brown line: chopstick. When it’s landing, the stick will be pushed up and pull the gate up as well.
5. Purple line: straw. They are holding the stick in place.
6. Red line: it connects the parachute.

III. Test

Score rules: better performance earns less penalty. Further away from the bull’s eye, a larger crack, or doesn’t touch will earn more penalty points. Each team has two eggs, the team with the least points wins.

We tested twice, and the egg lived twice.

Another team didn’t use any mechanism, even if the shell touched the ground, there was a small crack.

And the three videos below are just for fun. Honestly, I really want to see how theirs works.