Krazy+Krash+Kushion


 * Names**: Anna & Jeanette


 * Lab Goal/Question:** What material will lessen the impact of a collision of a cart the most?

-Marshmallows (assorted sizes) -Brick -Bubble wrap (assorted sizes) -Ziploc bags (inflated) -Water Ball -Logger Pro -Cart -Track
 * Materials/Procedure:**

1.Gather, check, and mass all materials. 2.Set up a ramp, a brick, a cart and Logger Pro. The brick should be in front of the cart, at an apporpriate didstance away, and the Logger Pro should be behind the cart. 3. Do a controled run, using just the cart crashing into the brick, and record the acceleration. 4.Repeat step 3, as many times as needed, using different materials to cushion the cart's impact. (Place materials used to cushion in front of the brick between the brick and the cart.) 5.Calculate the force involved with the equation of force equals mass multiplied by acceleration.


 * Data/Calculations:**







-Mass of Cart used - 255 g. -Equation used - force = mass of cart x acceleration




 * Conclusion:**

As we calculated all of the forces using the equation of force = mass x acceleration, using 255 g as our mass of the cart, we found the forces as stated above in our data table. Ultimately, we found that the constant, with just the brick alone had a force of -1255.62 N and that all of the objects that we used were able to absorb some of the impact, and thus make the force less. However, we found that the best object that could be used was the big marshmallow, that had a total force of -526.05 N, which is a difference of 729.57 N and that the worst object tested was the Water Ball, that only decreased the force by 316.71 N to a total of -938.91 N.

The data that we collected goes along with what we initially thought would occur. We set out on this experiment with the thought that the marshmallows would do the best, and that either the bubble wrap of the ball would do the worst. Our thoughts on the ball is that the ball compresses much more than the other objects used, which means that the cart easily could have hit the brick with as much force while using the ball. The marshmallows, on the other hand, were less easy to compress, and because the large marshmallow was so massive, at a whopping 18 grams, we felt as though it would soak up more of the force, causing the acceleration of the cart back to the sensor to decrease, which it did, by more than half of the original.

While we attempted to keep the experiment as constant as possible, we still may have had faults in data calculations. First of all, we may have not used the same amount of force to start the cart, which could, in effect, change the acceleration that we recorded after the cart hit the object. Also, we may have not used the most accurate represenations of the slope involved with the velocity graph, and may have included parts of the graph that were not involved with the acceleration following contact with the object. Over all, if we were to redo this experiment, we would be more careful of the graphs that we used and the force in which we used to initially move the cart.



The most surprising finding in this experiment was the differentiation between the acceleration and force using the different sizes of marshmallows. We thought that because marshmallows weighed very little, are basically made of air, and are easily compressed, that they would do the best in this experiment. However, we thought that the since a single small marshmallow only had a mass of 0.06 grams, only a fraction of the total of the regular marshmallow, that it would show bad results when using only one. Our data, in return proved us wrong, seeing as it decreased the force by over 300 N, which is amazing due to the small mass of the object.