Physics

Air-Powered Projectile Pre-Lab

Purpose: To investigate projectile motion.

To compare calculations to actual measurements.

Introduction: The “rockets” we will launch are powered by air. Each rocket has 4 thrust washers that will allow the rocket to launch with varying velocities. The thrust washers are labeled super, high, medium, and low. For this lab, choose one thrust washer and use it for all launches.

First we will determine the initial velocity of the rocket. Then we will complete the pre-lab calculations. The following day(s) we will perform the launches and take data that hopefully will match our calculations. We will be comparing the calculated time and range to the measured values for each angle the rocket is launched from.

SAFETY PRECAUTIONS

Ø All projectiles are potentially dangerous.

Ø Do not stand over the rocket while pumping the air pump.

Ø Only one group may launch at a time. All students should be notified of a launch. No one will be in range of the projectile at the time of the launch.

Ø Do not attempt to catch the rocket.

Ø Use caution handling the rocket as the plastic fins are very rough and plastic shards hurt.

Ø Pay attention!!!!

Pre-Lab Questions

1. In your group, devise a plan to determine the initial velocity of the rocket.

*What data do you need?

*What data are you able to measure?

2. If the thrust washer remains constant, will the initial velocity of your rocket change?

Pre-Lab Calculations

Thrust Washer = _______________

1. Calculate the initial velocity of your rocket.

2. Calculate the air time and range for each of the wedges provided. Be sure to use the launch angle and not the wedge angle in the calculations. Organize your results in a table/chart so that you can easily compare them to your measured results.

(You may share the work and turn in a final chart for each group.)

Lab Data

You should launch the rocket from each wedge possible at least once. Multiple trials would be best if time permits, and then take an average. Record the following data.

Wedge angle

Launch angle

Air time

Range

Analysis

Explain any variations in your measured values and calculated values for the range and time for each angle. Include a percent error analysis for 2 of the launch angles.

Conclusion

1. What launch angle produced the maximum range?

2. What launch angle was in the air the longest?

3. Did any rockets reach the same range when launched from different angles? If so, what is the relationship between those angles?

4. Comments, concerns, questions, ....