| motion_lab_graph.pdf |
| motion_lab_calc_graph.doc |
Lab: Interpreting and Matching
Displacement vs. Time Motion Graphs
Objectives:
Materials:
TI-84 Calculator-Based Lab Unit (CBL-II)
Motion detector
Meter stick
Computer with LoggerPro software
Procedure:
Part I –
1. Develop a position vs. time story that describes a body in motion incorporating at least the following four types of motion.
i. standing still
ii. moving with constant velocity
iii. moving with variable negative velocity
iv. moving with variable positive velocity
2. Illustrate the story on a position vs. time graph. Use a legend to cross reference sections of the graph with the corresponding sections of the story.
3. Underneath the graph, write instructions for moving in front of the motion detector according to the graph you have drawn (see page 2 for example).
Part II – AT THE LAB STATION IN CLASS WITH A PARTNER
4. Measure out and mark meaningful locations on the floor and practice the motion needed to create the position vs. time graph.
5. Now it’s time for you to match your physical motion to your group’s descriptive motion graph. You have 3 attempts to match it as best you can. Save a copy best graph your motion creates and reproduce this graph using LoggerPro. See Mrs. Geddes if you need instructions for uploading data to LoggerPro.
Your lab report should include your story and corresponding graph, and the graph made using the motion detector.
Story:
1) Dr. Egor is driving to school one day. In one minute, he drives 300 meters from his house. Suddenly, he stops to help a stoner who has caught his house on fire.
2) He stops at the house for 10 minutes to put out the fire.
3) Afterwards, he leaves the house to see that his car has run away. For 3 minutes he chases it. When he finally catches it, he is has moved 20 meters back in the direction of his house.
4) However, instead of driving his car tow work, he sees a magical unicorn on the side of the road. He gets on the back of the unicorn and speeds off to school 500 meters away. It takes him only two minutes.
Illustrated Graph:
See attachment
Motion Instructions:
1) Stand directly in front of motion sensor, at 0 meters.
2) In 1.5 seconds, quickly back up about one meter. Remain stationary for 5 seconds.
3) For 1 second, move roughly ½ meter forward towards the sensor.
4) Now, run away from the sensor as fast as possible, until it no longer detects your motion.
Motion Graph and Data:
Time(s) Distance(m)
0 0.162708
0.25 0.331524
0.5 0.793826
0.75 1.01234
1 1.11619
1.25 1.16228
1.5 1.18782
1.75 1.19393
2 1.19532
2.25 1.19726
2.5 1.19699
2.75 1.19865
3 1.20171
3.25 1.2042
3.5 1.20004
3.75 1.19643
4 1.20087
4.25 1.20559
4.5 1.20754
4.75 1.2067
5 1.20254
5.25 1.14423
5.5 1.0701
5.75 0.970139
6 0.892394
6.25 1.11758
6.5 1.71815
6.75 2.23
7 4
See attachment for graph
Data Analysis: Discuss differences between the descriptive graph and the graph generated by the motion detector. What are the reasons for the differences?
There are many factors that caused small discrepancies between our hand-drawn graph and our motion-generated graph. First, we had a 16 minute story that had to be converted to an 8-second sequence in front of the motion sensor, which proved to be difficult to duplicate exactly. The main reason for the difference was our inability to move fast enough to get the desired acceleration seen on the hand-drawn graph. Also, we could not replicate exactly the distances needed to correspond with our original graph. However, after many attempts, we were able to get a graph from the motion sensor that was very similar to our hand-drawn graph.
Conclusion: Develop a conclusion that addresses the objectives of the lab.
After completing this lab, I now have a far greater understanding of the concepts of motion, velocity, and acceleration. By creating the motion ourselves and generating our own graphs from that motion, it becomes much clearer than simply reading a textbook or powerpoint. From using the motion sensor, I learned how to create acceleration on the graph and how hard it really is to get quick accelerations in a position vs. time graph, just as we did for our story. Describing motion and then actually creating it are very different and not as easy as it may seem. This lab was an ideal way to get a better understanding of position vs. time graphs and the motion, velocity, and acceleration depicted by them.
Displacement vs. Time Motion Graphs
Objectives:
- Create a Displacement vs. Time graph and match your graph with actual motion.
- Gain competence in the use of motion detector and related equipment.
- Understand the relationship between position vs. time, velocity and acceleration.
Materials:
TI-84 Calculator-Based Lab Unit (CBL-II)
Motion detector
Meter stick
Computer with LoggerPro software
Procedure:
Part I –
1. Develop a position vs. time story that describes a body in motion incorporating at least the following four types of motion.
i. standing still
ii. moving with constant velocity
iii. moving with variable negative velocity
iv. moving with variable positive velocity
2. Illustrate the story on a position vs. time graph. Use a legend to cross reference sections of the graph with the corresponding sections of the story.
3. Underneath the graph, write instructions for moving in front of the motion detector according to the graph you have drawn (see page 2 for example).
Part II – AT THE LAB STATION IN CLASS WITH A PARTNER
4. Measure out and mark meaningful locations on the floor and practice the motion needed to create the position vs. time graph.
5. Now it’s time for you to match your physical motion to your group’s descriptive motion graph. You have 3 attempts to match it as best you can. Save a copy best graph your motion creates and reproduce this graph using LoggerPro. See Mrs. Geddes if you need instructions for uploading data to LoggerPro.
Your lab report should include your story and corresponding graph, and the graph made using the motion detector.
Story:
1) Dr. Egor is driving to school one day. In one minute, he drives 300 meters from his house. Suddenly, he stops to help a stoner who has caught his house on fire.
2) He stops at the house for 10 minutes to put out the fire.
3) Afterwards, he leaves the house to see that his car has run away. For 3 minutes he chases it. When he finally catches it, he is has moved 20 meters back in the direction of his house.
4) However, instead of driving his car tow work, he sees a magical unicorn on the side of the road. He gets on the back of the unicorn and speeds off to school 500 meters away. It takes him only two minutes.
Illustrated Graph:
See attachment
Motion Instructions:
1) Stand directly in front of motion sensor, at 0 meters.
2) In 1.5 seconds, quickly back up about one meter. Remain stationary for 5 seconds.
3) For 1 second, move roughly ½ meter forward towards the sensor.
4) Now, run away from the sensor as fast as possible, until it no longer detects your motion.
Motion Graph and Data:
Time(s) Distance(m)
0 0.162708
0.25 0.331524
0.5 0.793826
0.75 1.01234
1 1.11619
1.25 1.16228
1.5 1.18782
1.75 1.19393
2 1.19532
2.25 1.19726
2.5 1.19699
2.75 1.19865
3 1.20171
3.25 1.2042
3.5 1.20004
3.75 1.19643
4 1.20087
4.25 1.20559
4.5 1.20754
4.75 1.2067
5 1.20254
5.25 1.14423
5.5 1.0701
5.75 0.970139
6 0.892394
6.25 1.11758
6.5 1.71815
6.75 2.23
7 4
See attachment for graph
Data Analysis: Discuss differences between the descriptive graph and the graph generated by the motion detector. What are the reasons for the differences?
There are many factors that caused small discrepancies between our hand-drawn graph and our motion-generated graph. First, we had a 16 minute story that had to be converted to an 8-second sequence in front of the motion sensor, which proved to be difficult to duplicate exactly. The main reason for the difference was our inability to move fast enough to get the desired acceleration seen on the hand-drawn graph. Also, we could not replicate exactly the distances needed to correspond with our original graph. However, after many attempts, we were able to get a graph from the motion sensor that was very similar to our hand-drawn graph.
Conclusion: Develop a conclusion that addresses the objectives of the lab.
After completing this lab, I now have a far greater understanding of the concepts of motion, velocity, and acceleration. By creating the motion ourselves and generating our own graphs from that motion, it becomes much clearer than simply reading a textbook or powerpoint. From using the motion sensor, I learned how to create acceleration on the graph and how hard it really is to get quick accelerations in a position vs. time graph, just as we did for our story. Describing motion and then actually creating it are very different and not as easy as it may seem. This lab was an ideal way to get a better understanding of position vs. time graphs and the motion, velocity, and acceleration depicted by them.
