For more details on this lab, go to this page.
On this day - we dropped different masses onto the cans below - or students dropped a mass at different heights and measured the resulting can's height.
For more details on this lab, go to this page.
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In this video, we examine old technology and with more mass, v. new technology and with smaller mass. What do you think will happen as a final result? Question: What factors affect a collision between two cars? In other words, what makes the difference between a super colossal crash v. a small fender bender? Student Hypothesies:
Out of this will come two labs. One based on speed and another based on mass. Both will look at collisions with a car colliding with a box of tissues - where we will measure the distance the box of tissues moves. EXPERIMENT No. 1: Speed v. DistanceSince we know that height affects speed, we're changing up the height to increase speed. Question: How does the height / speed of a moving car affect the distance a tissue box moves? Experimental Design: What we're going to do is change the speed of the car rolling down the ramp by changing the height of the ramp and measuring the distance the box of tissues moves after it collides. Results: Reflection: C: Make a claim that shows your trend and answers your question at the same time. E: What evidence do you have that supports your claim? R: What is the reason why behind your results? Mass v. DistanceBelow is a student running the experiment. Observe the mass she used and measure the distance the box of tissues moved, and make a data table out of the information provided below. (hint, to find the data, look at the caption below the pictures). Reflection:
C: Make a claim that shows your trend and answers your question at the same time. E: What evidence do you have that supports your claim? R: What is the reason why behind your results? Vocabulary:
Energy Simulations on Phet
Meteorite Impact Online Calculator:
Additional Meteorite Impact Study Material Environmental Impact - paleo:
After running the last of the mini experiments - with the last of the mini experiments - we asked if speed makes a difference with depth to which we threw a ball into the flour and dropped another one into the flour - and notice that it does. After that, we ask if height the ball is dropped makes a difference? To which they reply that yes it does. When pushed further - they answer that it increases the speed (final velocity). This was the question & hypothesis that created the perfect segway into the next lab: Does height increase a balls (average) velocity? Experimental Design:
Results: We are seeing two strong trends in both graphs.
Conclusion:
Yes, height does increase the final velocity of a falling object. Day 1: Phenomena & question & hypothesis generation
Day 2: Group phenomena and set up the experimental design to test the "size" hypothesis
Day 4: Data Analysis
Since our set of hypothesis demand more experiments, we're going to run a few of them right here.
Experiment 2: Material of the ground Question: Does the material of the ground determine how far the meteorite will go down? Experimental Design: To test this, we're going to drop a cue ball 1 m high into different materials and compare the two to see how far the balls went down. Material 1: Flour Material 2: Sand Results: The cue ball in flour went significantly down much farther than the cue ball in sand. Reflection & Conclusion: Yes, materials do make a difference. The reason being is that the softer material (flour) is more compactable and moveable - to where as the sand is not Experiment 3: Material of the meteor (ball) Question: Does the material of the meteor determine how far the meteorite will go down? Experimental Design: To test this, we're going to drop a solid v. squishy ball into the flour to see if it makes a difference. Ball 1: Hard Baseball Ball 2: Soft squishy ball Results: The baseball did go down further - but knowing that mass makes a difference, we're not sure if it's mass that made the difference or if it was because the baseball was harder. Conclusion: We're not sure. Inconclusive. Experiment 4: Velocity Question: Does a difference in velocity make the meteor (ball) go deeper into the ground? Experimental Design: To test this, we will drop a ball 0.3 meters into the flour and compare it to the same ball thrown into the flour and measure how far it went down. Results & Reflection: The ball that was thrown into the flour definitely went deeper than the ball that was dropped at a small height. This is because it had a greater amount of momentum the moment it collided with the flour. Experiment 5: Height Question: Does the height a ball is dropped make a difference? Experimental Design: To test this, we will drop a ball at different heights to see if it makes a difference in depth. The low ball will be dropped at 0.5 m and the second ball will be dropped at 3.0 m. Results & Reflection: What we noticed was that the ball at the higher height was significantly deeper than the ball that was dropped at a lower height. We think this is because as a ball falls from a higher height, the ball increases speed. Experiment 6: Does Height affect Velocity? Question: Does height increase speed? Question:
Hypothesis:
Experimental Design:
Volume = 4/3 pi r^3
Density = Mass / Volume
Results: Here are the results from me and a group of studentsMethodology: For our experiment, we only ran test once with each ball. We dropped the ball 1m high and dropped it into a bucket of flour that was much deeper. I am beginning to think that the deeper flour made a difference, as it may have compressed the flour with the smaller bucket. Data Analysis Questions to consider: Step 1. Break up each graph into 4 quadrants based on the spectrum of volume to depth, mass to depth & density to depth. Step 2: Identify which balls land in each quadrant. Step 3: If you see any trends, represent that trend with either a curved or straight line. Step 4: Answer the following questions. Volume v. Depth:
Mass v. Depth:
Density v. Depth:
Final Thoughts:
* Be prepared to share your findings with the rest of the class. Students doing data analysisReflection:
After running multiple tests of dropping balls 1 m high into a bowl full of flour, I am convinced that the surface area due to the relative volume of the ball works against deeper penetration into the soil as indicated by the "volume v. depth" graph and the "volume v. crater diameter" graph. It also appears that volume or surface area works great with building wider craters that it does deeper penetration. In the "volume v. depth" graph, there were no clear trends. However, there were clear trends with "mass v. depth" and "density v. depth". Upon further investigation, it would appear that the less surface area and increased mass tend to be the biggest culprit for deeper penetration. In fact, it seems that mass is what is doing the bulk of the work to penetrate deeper into the flour upon impact as indicated in the "mass v. depth" graph and "density v. depth" graph. In fact, when comparing the golf ball to the wiffle ball, both having the same volume but clearly different masses, the golf ball penetrated much deeper than the wiffle ball. Simultaneously, the crater was also slightly bigger as well. When comparing the large and small marbles, the density was about the same, but the larger marble clearly had more mass and was able to penetrate much deeper. When comparing the cue ball to the racquetball, the cue ball, both of which have the same volume, but clearly the cue ball having more mass, the cue ball went much further down than the racquetball. Again, suggesting that having more mass is what allows the ball to penetrate through even deeper. If I were to drop the baseball and compared it to a wiffle ball the same size (volume), my guess would be that the baseball would also go much further than the wiffle ball based on the same premise, in that the baseball contains more mass, and would therefore go much deeper than the wiffle ball. What I also find fascinating, however, is that the wiffle ball would not create a big crater. If volume determines the crater size, clearly mass also plays a role with that as well - as the crater tends to be conical in shape and not simply a straight shaft going down. Upon further reflection, I'd also like to add that the reason why any ball penetrates in the flour has something to do with the ball's position and properties prior to its impact. Meaning - that the reasons why the ball penetrates deeply has something more to do with the falling process and respective mass as the property of the ball than it does density. Density only seems to matter after contact and introduction into a different medium - meaning, going from air to ground. The speed of the ball would also have something to do with it as well. If a ball doesn't move very fast, there is no way that it would be able to penetrate through very far. In other words, if all I had was mass alone, and placed it on the top of the flour, the ball wouldn't go very far. If I threw the ball into the flour, I would highly suspect that it would penetrate much deeper. The question I have, is can I increase the speed with the balls height? Since our hypothesis also includes a difference in speed, the the next series of tests must examine how speed influences penetration. I suspect that the height the ball is dropped will influence the speed of the ball when it hits the flour - so we will need to examine to see if height really does influence the final speed prior to impact. To do that, we will roll a marble down a ramp at a fixed angle, but at various different heights along that same ramp, and time the marble as it descends down the ramp. If the ball does indeed go faster, we should see a curving upward trend on a distance v time graph. If this is the case, then we can drop a ball at various different heights, which will provide us with increased speeds, to give us different results.
Day 1: Task 1: Use the powerpoint above and the video below to observe as much phenomena as you possibly can and develop questions along the way. |
Brian D. BeadleI'm the science teacher for my classroom at Vista Heights Middle School Archives
May 2018
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