Lab 2: Motion x(t)! v(t)! a(t)

Transcription

1 PS 12A Names: Lab 2: Motion x(t)! v(t)! a(t) In this first lab we will look at the motion of some different objects. We are interested in how we can represent the motion in a variety of ways. This will include using written descriptions, graphs, and motion maps. Remember to answer each question fully and include units on all relevant quantities! Warm-Up: On the lab table is a battery-operated buggy. Devise a way to measure its velocity to your best estimate (lowest error). Use the stopwatches and meter sticks to help you. Graph this motion on the graph paper provided. Describe the motion of the buggy. Create a motion map (Arrows that represent the displacement and velocity of the motion) Assigning error: What is the error in your time measurements? What is the error in your displacement measurements? Represent these on your graph. What is the average speed of the buggy? How did you find this? What is the maximum and minimum possible speeds of the buggy? Create velocity vs. time graphs and acceleration vs. time graphs for the buggy s motion Part I: Position vs. Time In this section consider the following plot of position versus time. You will determine how to recreate that plot by walking in front of the motion detector.

2 (a) Describe the motion (i.e., I stood still for a second then ) (b) What is the total displacement traveled in the above plot? (c) What is the total distance traveled in the above plot? (d) In what time range did the person move the fastest? How fast did he move and in what direction? Explain your answer. (e) Create corresponding velocity vs. time and acceleration vs. time graphs (f) Using the motion sensor recreate the above position vs. time plot. Show your TA.

3 Part II: Velocity vs. Time In this section, consider the following plot of velocity versus time. You will determine how to recreate the plot by walking in front of the motion detector. (a) Describe the motion (i.e., I stood still for a second, then ) (b) What is the total distance traveled in the above plot?

4 (c) What is the total displacement in the above plot? (d) In what time range did the person move the fastest? How fast did she move and in what direction? Explain your answer. (e) Create corresponding velocity vs. time and acceleration vs. time graph (f) Using the motion sensor recreate the above velocity vs. time plot. Show your TA

5 Part III: Acceleration vs. Time In this section, consider the following plot of acceleration versus time. You will determine how to recreate the plot by walking in front of the motion detector. (a) Describe the motion you underwent (i.e., I stood still for a second, then ) (b) What is the total displacement in the above plot? Do you have all the info

6 needed? (c) What is the total distance traveled in the above plot? (d) In what time range did the person move the fastest? How fast did she move and in what direction? Explain your answer. (e) Recreate the Acceleration vs. time plot. Show your TA. (f) Using the motion sensor recreate the Acceleration vs. time plot. If it helps there is a program on the desktop called Graphs and Tracks that may make things easier.

7 Part IV: Describing more interesting motion On your bench is an example of an object with more interesting motion. After gaining an initial qualitative understanding of the object s motion, use the equipment on your desk (cameras, sensors, rulers, etc.) to make quantitative statements about the motion. This includes, but is not limited to, motion diagrams and graphs of position, velocity and acceleration. Make note of any interesting features of the motion as well. You ll be given a large tablet of paper for use in a short presentation to the class at the end of the lab period. Please draw on the paper large enough so that everyone can see. During the presentation, Tell us about your object Give a short description of the motion Predict what the displacement, velocity, and acceleration graphs Analyze the motion Describe any difficulties that your group encountered