Egg Bungee Jump

1. Egg Bungee Jump S.T.E.M. Challenge Engineering Design Process PBSKids.org

2. What do we already know? What causes you to fall? How close do you come to the ground? What slows down your speed while falling? How does the cord work? What is the purpose of the cord? Does height impact your speed?

3. What’s the science behind a bungee? • When you launch a person, it falls to the ground because of gravity • As the person falls, its weight stretches the cord because it is elastic • A material described as elastic has the ability to return almost to its original shape after it has been stretched by force • The amount of stretching depends on the worth of the person jumping and how fast the person is falling.

4. Here’s the challenge… • Design a bungee jump for an egg so that the egg comes within two inches of the floor without cracking! • Think of ways to use the stocking to make a bungee cord • Make a test egg (fill a plastic bag with weights or pennies until it weighs about the same as a real egg) • Test you bungee design with the test egg (put the test egg inside the stocking, hold one end of the stocking and drop the egg from the launch site, measure how close the test egg comes to the ground) • Evaluate your design (What changes can you make to improve your bungee design?) • When you’re ready, try your bungee design with a real egg (Spread some newspaper underneath your launch site, just in case the egg breaks!)

5. What will you need? Materials Group Member Jobs Egg Nylon stockings Plastic sandwich bag Weights Rubber bands Yardstick Tape Scissors Newspaper Head Hands Heart Mouth Check out these kids just like you solving this challenge… Egg Bungee- Zoom Science- Zoom Into Engineering

6. Variables to think about… • By changing the length of the nylon stocking, you can adjust how close an egg comes to the floor. You can increase the length by tying stockings together or decrease the length by cutting or knotting them. • The weight of the egg is what stretches the stocking. Each egg has a different weight and stretches the stocking to a different length. It’s important to have the “test” egg weigh roughly the same as the real egg. Otherwise the final launch may miss its mark. • Different types of stockings have different degrees of elasticity. As you stretch a stocking again and again, it will lose some of its elasticity because the fibers become “fatigued” and do not return to their original length.

7. Question that… • Did the egg come to within 2 inches of the floor? If not, what could you change so that it does? • What happens if you change the bungee cord length by adding stockings or cutting the stockings? • What happens if you add more weight to the egg? • What happens if you use a different type of stocking? • What happens if you change the way the materials are arranged for the bungee? • What design did you use? How successful was your design? How might you have changed your design if you tried the activity again?

8. Cool STEM Careers- • How can we apply what we learned from this challenge to a S.T.E.M. career? • How can we apply what we learned from this challenge to real life? • How did we apply what we learned from other S.T.E.M. challenges to this challenge? • Annie, Gloria, Nate, and Aitor • Space Suit Research Engineers • International Space Station • Mars Exploration

9. Egg Drop Challenge… • Next week is the 3rd Annual Egg Drop Challenge! • How can the Egg Bungee Jump Challenge help us with the Egg Drop Challenge? • What did we learn during the Egg Bungee about speed? • What did we learn during the Egg Bungee about the egg? • What did we learn about working as a team during the Egg Bungee? • What did we learn about materials during the Egg Bungee challenge?