An egg drop project challenges you to protect a raw egg from breaking when it falls from a height, such as 2 meters. It is a fun way to test engineering ideas because the egg is fragile, but the materials are simple. Cardboard, padding, tape, string, and a plastic bag can become a real crash protection system.
The goal is to make the egg land with less force on its shell.
Key Facts
- Gravitational potential energy before the drop is PE = mgh.
- Just before impact, much of the potential energy becomes kinetic energy, KE = 1/2 mv^2.
- A 2 meter drop gives an ideal impact speed of about v = 6.3 m/s if air resistance is small.
- Impact force can be reduced by increasing stopping distance or stopping time.
- Impulse is J = FΔt, so a longer impact time usually means a smaller average force.
- Four useful egg protection strategies are cushioning, parachute, crumple zone, and suspension.
Vocabulary
- Kinetic energy
- Kinetic energy is the energy an object has because it is moving.
- Impact force
- Impact force is the push or squeeze on an object when it hits another object.
- Cushioning
- Cushioning is soft material that spreads out the force of a collision and slows the object more gently.
- Crumple zone
- A crumple zone is a part of a design that bends or crushes to absorb energy during a crash.
- Suspension
- Suspension is a method of holding the egg away from hard surfaces using stretchy or flexible supports.
Common Mistakes to Avoid
- Packing the egg tightly against a hard wall is wrong because the shell feels the impact almost instantly. Leave room for padding or suspension to slow the egg down.
- Using only a parachute and no padding is wrong because the device can still land hard or tip over. Add cushioning or a crumple zone for the final impact.
- Making the container very heavy is wrong because a heavier device has more energy to manage when it hits the floor. Keep the design strong but lightweight.
- Taping everything so it cannot move is wrong because some movement helps absorb energy. Let padding compress, cardboard bend, or strings stretch during impact.
Practice Questions
- 1 A 0.05 kg egg is dropped from 2 m. Using PE = mgh with g = 9.8 m/s^2, how much gravitational potential energy does the egg have before it is dropped?
- 2 A falling egg-drop device slows to a stop in 0.02 s when it hits the floor. If a better cushion makes it stop in 0.10 s, how many times longer is the stopping time?
- 3 A team can add either a plastic bag parachute or a cardboard crumple zone, but not both. Explain which one you would choose for a 2 meter classroom drop and what problem your choice solves.