Impulse and momentum

Objective:

In this exercise you will analyze two video clips.  The clips show a cart being pulled by a constant force F for some time interval Dt.  The velocity of the cart at t = 0 is zero.  After the time interval the force is zero and the cart moves with approximately constant velocity.   You will determine the magnitude of the impulse I = FDt received by the cart, and its velocity and momentum after the force has dropped to zero.

Procedure:

To play a video clip or to step through it frame-by-frame click the "Begin" button.  The "Video Analysis" web page will open.  You can toggle between the current page and the "Video Analysis" page by pressing Alt-Tab.  Choose the impulse_1.avi and the impulse_2.avi video clips. 

To find the magnitude of the impulse received by the cart, step through the video clip frame-by-frame and note the time interval Dt through which the force acts.  Multiply the force sensor reading by Dt to find the magnitude of the impulse I.  Estimate the uncertainty in F, Dt, and I.
To find the final velocity of the cart step through the video clip and start taking data after the force has dropped to zero.  Determine the  position of the cart as a function of time by stepping through the video clip frame-by-frame and by reading the time and the position coordinates of the cart off each frame.  Construct a spreadsheet with columns for time and position.  The slope of a position versus time graph yields the velocity of the cart.
To find the magnitude of the final momentum p of the cart multiply its speed by its mass.  Estimate the uncertainty in the magnitude of the final momentum p.
Compare I and p.  Comment on your results.

To earn extra credit add your name and e-mail address to your spreadsheet.  In full sentences answer the following question.

What values did you obtain for I and p (numbers and units) for the video clip impulse_1.avi?
What are your estimated uncertainties for F, Dt, I, and p?
Do I and p agree within your estimated uncertainties?  Comment on your results.
What values did you obtain for I and p (numbers and units) for the video clip impulse_2.avi?
What are your estimated uncertainties for F, Dt, I, and p?
Do I and p agree within your estimated uncertainties?  Comment on your results.

Save your Excel document (your name_exm7.xls) and attach it to an e-mail message to your instructor.