In this experiment, students derive Newton's 2nd Law.

• Microsoft Word version of this lab:
  
  • SecondLawGLX_docs.zip (1.3 MB)

• Xplorer GLX (PS-2002)
• PASPORT Force Sensor (PS-2104)
• PASPORT Motion Sensor (PS-2103A)
• PASCar (ME-6950)
• PASTrack (ME-6960) - Ships March, 2008
• Ohaus Triple Beam Balance (SE-8723)

1. Arrange the equipment as in the picture above. Make sure the of the cart nearest the Motion Sensor is 15 cm away from the Motion Sensor.
2. Press the button on the Xplorer GLX.
3. While holding onto the hook of the Force Sensor, pull the Cart/Force Sensor 15 cm away from the Motion Sensor. Push it back to the original position. Continue this back and force motion for approximately 20 seconds.
4. Press the button on the Xplorer GLX.
5. In order to view the graph easier, press the F1 Button to Auto Scale.
   

   

6. The data should look like the graph above. If not, have the instructor check your setup. If the data does look like the graph above, press the F3 Button. Select "Linear Fit."
7. Record the slope and vertical intercept in Data/Analysis Table 1.
8. If the data does look like the graph above, press the F3 Button. Select "Linear Fit."
   

   

9. To delete the data, press the Check Button. Navigate to the "Run" box using the Arrow Buttons. Select "Delete All Runs…"
10. Repeat the previous steps two more times.
11. Using the balance, find the mass of the Cart and Force Sensor. Record this value.

Mass of Cart and Force Sensor: _______________ kg

1. Draw a free body (force) diagram of the Cart/Force Sensor as it is pulled away from the Motion Sensor.
2. Draw velocity vectors that represent the relative values of the velocity of the Cart/Force Sensor. (Also referred to as a "velocity motion map.")
3. Draw acceleration vectors that represent the relative values of the acceleration of the Cart/Force Sensor. (Also referred to as an "acceleration motion map.")
4. Compare the average slope of the graph to the mass of the Cart/Force Sensor. What is the physical meaning of the slope of the Force-Acceleration graph?
5. Write a y=mx+b equation for the graph using the proper variables and units.