First Task: Find the force required to shatter an egg and the force delivered to car by the wall
Shattering the egg
Since force equals mass times acceleration, we will drop the egg from different heights and use a motion sensor to calculate its acceleration. We will also have to find the egg's mass in order to find force.
Egg's mass = 0.05773 Kg
Egg's acceleration = 1.5 m/s2
Force = 0.0900588 N
After several trials, we found out that our method was the most complicated and inaccurate. We found the force by measuring the egg's acceleration and its mass. Then, the egg was dropped, and in the first trial the egg's shell broke. Once the egg was broken, no more trials could be done, so we missed more information.
Finally we decided to use the class average as our force, because the force we calculated was way off.
*The egg was named "Nemo"*
Class average: 11.6N
Wall's impact on car
We calculated the impact force by placing a force sensor at the end of the ramp, where the books are located and then the car is released. The impact at the end is calculated by the sensor, and that's the impact with witch the car will hit.
Mass of car = 262.5 g
Force = 65.79N
The force calculated was for the car only, so adding the egg and the equipment to make it survive the impact will change this, because its mass is increased. So we need to take that into account.
We will also place a ball at the front of the car, so the car won't impact so directly with the wall and the time will be increased
Second Task: Answering Questions
Based on the impulse equation, in order for an egg to survive an impact, should the collision take a longer time or a shorter time?
You cannot change the impulse of an object, for example, if you are in a crash, the impulse will always be the same with or without a airbag. What the airbag does is increase the time in which the force is applied, and because impulse equals force time (J = F x t), so if the time is increase, the force is reduced.
Based on the momentum equation, in order for an egg to survive an impact, should the collision occur at a higher or lower velocity?
The momentum formula is mass times velocity, we need to decrease velocity for the moment to be smaller, and so, the change in momentum (impulse) will also be small and the egg will be less likely to brake.
Third Task: Designing the Car
First of all, the main reason why we used these materials (cotton, foam balls and a box) was because we wanted to but the egg in a box or something where it wouldn't fly out of the cart; the box was a good option. We wanted the egg to be suspended inside the box, so if we speak in biology terms, we used a material that would make the egg be like an organelle inside the cytoplasm of a cell. In that way, the egg was protected from breaking when the cart hit the ground.
Now, we'll explain our experiment better by estimating some data. Let's start off with the cart's velocity when it hit the wall. Then, we'll continue with momentum, and finish with impulse.
Estimated velocity= - 1.38 m/s
Change in momentum= 1.38 Kg m/s
Impulse= -1.48 Ns
Force the cart will hit the wall with= -1.26 N
The final estimation is how long will the impact last, so the estimation is that the impact will last 1.30 s.
To be determined/reported
And now, you are about to watch the ultimate egg-in-a-cart experiment!