Video: Watch this demo
Description: This demonstration shows the importance of impulse.
- Large white sheet with hooks
- 2-3 Eggs
- (Optional) 2-3 hollow eggs
- Orange egg holder
- Step ladder
- Lots of paper towels
- Get 4-6 eggs. Place them in the orange egg holder and store in the frig until the class starts.
- Hang the white sheet to the top of the classroom using the step ladder (see picture). Spread the sheet out as much as possible.
- Throw the bottom of the sheet over the top so it does not take up as much room initially.
- Set the eggs, sponge, and paper towels to the side.
- (Optional) Before class, blow the inside of 2-3 eggs out.
- Open the sheet up fully.
- Have two people hold each side of the sheet on the bottom. This is so the the eggs does not hit the floor.
- Pick a strong student, preferably who plays baseball.
- Have them throw the egg against the sheet as hard as they can. Give them a few tries.
- You must stress that they do not squeeze the egg, and that they aim directly at the sheet (not to the side, above, or below).
- Note that it will not break. This is because the impulse is small, as the egg came to rest in a relatively long time.
- Throw the same egg the student used at the blackboard.
- Note the egg breaks on contact. This is because the impulse is high, as the time for the egg to come to rest is very short.
- Clean up the egg from the blackboard as soon as it breaks using a wet sponge and lots of paper towels.
- Compare the two different situations and why the egg breaks on the board and not in the sheet.
- (Optional) For fun, throw the 2-3 blown eggs (all at once) into the class to give the students a little scare.
Tips: Make sure to make a lip at the bottom of the sheet so the thrown egg does not fall to the ground.
Concepts: You can explain that this is essentially how a car air bag works.