Investigating a Balloon Jet
In this lab, you will examine the relationships among force, mass, and motion.
Problem How does a jet-powered device move?
Materials
string, 3 m in length
drinking straw
4 long balloons
masking tape
stopwatch
meter stick
2 threaded nuts
2 chairs
For the probeware version of this lab, see the Probeware Lab Manual, Lab 4.
Skills Applying Concepts
Procedure
On a separate sheet of paper, make a copy of the data table shown.
Insert the string through the straw and tie each end of the string to the back of a separate chair. Pull the chairs apart until the string is tight and horizontal.
Blow up the balloon and then hold the balloon's opening closed. Record the length of the balloon. Have a classmate attach the balloon lengthwise to the straw using tape.
While continuing to hold the balloon's opening closed, slide the balloon jet to the end of the string as shown.
Release the balloon. Measure the time during which the balloon jet moves. Measure the distance that the balloon jet travels along the string. Record the distance and time values in the data table for 0 Nuts Used, Trial 1.
Repeat Steps 3 through 5 with a new balloon. Make sure to inflate the balloon to the same size as in Step 3. Record your results in the data table for 0 Nuts Used, Trial 2.
Repeat Steps 3 through 6 twice more with a new balloon. This time, tape two nuts to the balloon before releasing it. Record your results in the data table for 2 Nuts Used, Trials 1 and 2.
Calculate and record the average speed for each trial. The average speed is equal to the distance divided by the time.
Analyze and Conclude
Applying Concepts Use Newton's second and third laws to explain the motion of the balloon jet.
Analyzing Data How did adding mass (nuts) to the balloon jet affect its motion?