Egg Drop Written Report: Chicken Little and his Spaceship Shannon Magee, Meghan Whitsitt SPH3U1 Mr. Braun December 13, 2013
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Egg Drop: Chicken Little Introduction: The purpose of the egg drop competition activity was to create a structure that would protect the egg being dropped from the bearpit without any collateral damage. Additionally, afterwards you had to make connections with similar real life structures, such as the Mars Rover. The name of our structure is the Chicken Little Spaceship. When it was dropped from the bearpit, our egg, Chicken Little, only received a small crack from the impact. Initial Design Strategy: Our initial design strategy included whirly gigs to decrease the acceleration rate and straws to create a crumple zone. The concept behind the whirly gigs was Newton s third law: the forces exerted between two (2) objects are equal in size and push in the opposite direction. So, due to Newton s third law, when the structure (wings of the whirly gigs) pushed down on the air, the air pushed up on it, and therefore decreased the net force. Because the net force was reduced, so was the acceleration due to Newton s third law: the relationship between force, mass and acceleration:. If the net force was reduced, and the mass stayed the same, the only way to keep the equation balanced is to reduce the acceleration. A reduced acceleration means a smaller deceleration when the structure hits the ground because the structure will reach a lower velocity on its way down. We also included straws around the egg in an attempt to create a crumple zone. Crumple zones increase the amount of time it takes for an object to come to a complete stop compared to the object it hits. By increasing the impact time it takes to stop an object, the force is spread out over a longer period of time. Due to Newton s law of inertia, the egg structure will want to keep moving downward because that s the direction of its motion. If you increase the collision time, you ll decrease the acceleration rate, and therefore decrease the net force acting on it as explained above. This means that the egg is likely to experience less injures due to the collision. Overall, it performed fairly well and the structure demonstrated the physics concepts behind its design. Digital Pictures and Video: Refer to website or YouTube. Page 6
Reflection: Our egg structure, Chicken Little s Spaceship, performed well, considering the whirlygigs didn t work as they were supposed to, but still slowed down the acceleration rate. Our egg, Chicken Little, only had minor injuries consisting of a small crack, unlike other eggs who were splattered all over the floor. However, due to lack of medical attention, within about half an hour he bled to death. The straw cage crumple zone was probably the reason why CL only received minor injuries, meaning that it performed as it should have and worked properly. Overall, the structure demonstrated the physics concepts of the design and executed its purpose to protect the egg adequately well. Calculations: Page 7
Research: The Mars landing and the egg drop task had many similarities. In the table below we will compare these similarities and discuss in terms of resources, timelines, materials, objective, and special features. Resources Mars Landing Egg Drop Task Timeline Materials Objective Special Features In April, 2004 NASA proposed a Mars rover mission. Testing of components also began in 2004. Over the next 8 years they would develop, prelaunch it and eventually land it on Mars. The materials used for the landing were the aero shell (a protective covering), which includes a parachute, back shell electronics, three large solid rocket motors, a heat shield and three small solid rockets. The objective of the Mars landing was to, of course, land the rover on Mars. This was in order to discover the biological, the geological and geochemical, and the surface area of Mars. The special features of the Mars rover, Curiosity, would be its heat rejection system that allows it to stay a certain temperature. The rover also used a parachute to slow down its velocity and a protective device that drew out the force of impact. We had a couple days outside of class in order generate a design that we believed would work correctly. We then had one day in class (and extra time in the morning or at lunch if we needed it) to build our structure. The materials we used were 15 straws, 2 cue cars and 1m of tape to build our structure. We both had limits and a budget to keep. The objective of the task was to land the egg safely in the Bear Pit without breaking it in anyway. This is similar to how the Mars rover could not be broken or it would be a bust. In the egg drop task we created a crumple zone with our straws and we used a whirly gig in order to slow the velocity of our structure down. Page 8
References: "Mars Exploration Rover Mission: The Mission." Mars Exploration Rover Mission: The Mission. N.p., n.d. Web. 13 Dec. 2013. "Timeline of Mars Science Laboratory." Wikipedia. N.p., n.d. Web. 12 Dec. 2013. "Curiosity (rover)." Wikipedia. N.p., n.d. Web. 12 Dec. 2013. Page 9