| Understanding the color code for PHY 241 |
| Raw Data | | Formula provided by instructor | | | | Formula that needs to be entered | | | | Open Response area |
| Prelab 3 |
| It is good idea to know roughly how the CBR we are using in lab works. After using echolocation/sonar to determine the position of a cart, the Logger Pro software calculates the velocity and acceleration. For this prelab we will be using our average velocity and average acceleration formulae to complete these calculations. |
| For Questions 1-3, Two different groups are measuring the SAME cart travelling with a constant velocity on a straight track. Table 1 and Table 2 represent the data collected by each group. |
| Table 1 | | | | | 1. Use the standard "Kinematics Equations" for velocity and acceleration to find these values for each time step in Table 1 and Table 2 as well as their average and uncertainty. Definitely take advantage of Excel's "Copy" and "Paste" functions so you only need to type equations once or twice. Give special attention to the cells on the edge of the data set. |
| Average Velocity: | | Average Acceleration: |
| Velocity Uncertainty: | | Acceleration Uncertainty: |
| Time (s) | Position (cm) | Velocity (cm/s) | Acceleration (cm/s/s) |
| 0 | 0 |
| 1 | 15.3 |
| 2 | 24.6 | | | | 2. Use proper rounding techniques to report the velocity and acceleration of the cart for each data table. (Note, because the data updates every time you edit this sheet, the instructor is aware that there might be a slight mismatch between your reported value and data showing at the time of submission.) |
| 3 | 39.675 |
| 4 | 53.525 |
| 5 | 64.7 |
| 6 | 80.3 |
| 7 | 92.275 |
| 8 | 104.45 | | | | Table 1: Velocity = |
| 9 | 118.1 |
| 10 | 134.4 | | | | Table 2: Velocity = |
| 11 | 143.85 |
| 12 | 157.125 | | | | Table 1: Acceleration = |
| 13 | 170.75 |
| 14 | 185.725 | | | | Table 2: Acceleration = |
| 15 | 195.575 |
| 16 | 210.8 | | | | 3. Are your results consistent with the description given above: "Two different groups are measuring the same cart travelling with constant velocity on a straight track." Explain any numerical inconsistencies that are in the data using your understanding of "Uncertainty". |
| 17 | 226.325 |
| 18 | 238.85 |
| 19 | 250.15 |
| Table 2 |
| Average Velocity | | Average Acceleration: |
| velocity uncertainty: | | Acceleration Uncertainty: |
| Time (s) | Position (cm) | Velocity (cm/s) | Acceleration (cm/s/s) |
| 0 | 0 |
| 0.1 | -0.855 |
| 0.2 | 4.89 |
| 0.3 | 5.11 | | | | 4. Compare and contrast the uncertainties measured by these two groups. Fundamentally what caused one group to get more precise data than another? |
| 0.4 | 7.18 |
| 0.5 | 4.525 |
| 0.6 | 8.32 |
| 0.7 | 9.465 |
| 0.8 | 8.41 |
| 0.9 | 11.53 |
| 1 | 12.675 |
| 1.1 | 16.17 |
| 1.2 | 18.315 |
| 1.3 | 18.985 |
| 1.4 | 17.155 |
| 1.5 | 21.025 |
| 1.6 | 22.045 |
| 1.7 | 24.765 |
| 1.8 | 25.86 |
| 1.9 | 27.155 |