Sandbox Shoot:
Purpose:
The purpose of this lab is to explore some of the features of projectile motion. In this lab you will use your understanding of projectile motion to characterize a launching mechanism. Using this information you will then make the needed calculations to determine where to place the target bucket relative to a starting position I will determine.
Procedure:
You will need the following items: spring launcher, meter sticks, and protractors. As always in lab you will need your minds (or at least some significant portion thereof ). A special note for this lab!!! BE AWARE OF THE SAFETY OF YOUR CLASSMATES! There will be some objects flying around and people could get hurt. Irresponsible behavior will be reflected in your grade.
- 1) Place the launcher on one of the counters. The ball catcher shown above will be removed. Launch the ball horizontally into the sand tray to protect the floor. By making appropriate measurements determine the initial velocity of the ball. Repeat these measurements 6-8 times to assess the variability of this determination. No other apparatus will be needed. Use this Maple Sandbox Worksheet to check your calculations and explore the effects of the variability in your data.
- 2) The launcher will then be placed on an incline on the bench at the front of the room. The task before you is to determine where to place the target bucket so that the ball will land on aline you draw in the sand. You will be permitted three attempts to allow for misfires but no adjustment of your launcher. Success (getting within 10 cm) will get each member of your group 10 extra points for use elsewhere in the course. In order to keep things fair each group will be dealing with slightly different launchers.
- 3) The following hints may
be useful:
- i) What is critical that you need to know about the physical situation?
- ii) How does the counter height affect the distance the ball goes?
- iii) What are the uncertainties in your setup?
- iv) Can you minimize the effects of these uncertainties?
LAB REPORT:
I) Describe the process by which you determined the initial velocity of the ball. Show your data and your calculations.
II) Based on your data (multiple measurements), determine the variability in your determination of the initial velocity using tools we have previously developed in this course. Express this variability quantitatively (in numbers!).
III) Present your data and calculations for the challenge portion of the experiment. Exactly how did you determine where to draw the line in the sand and how did you choose to position the sandbox? Your goal is effective communication of the process you used.
IV) Describe how your results are, or are not consistent with the results from the Maple Sandbox worksheet. Include a printout of a Maple plot relevant to your challenge solution and describe how you used it to determine the range of likely landing spots for your projectile.
