Period _____ Name ________________________ Number _____
MOTION OF A WATER BALLOON
Application
Purpose - The purpose of this activity is to calculate the bow velocity of a balloon and predict the maximum
range (horizontal distance) that the balloon will travel.
Materials - Balloons, Winger, Stopwatches, Tape measure, Trundle wheel and Calculator.
Procedure - Using concepts you have just studied, it should be possible for you to calculate the bow velocity
and the maximum range of a balloon. Because of the possible dangers, this will be demonstrated for the class
under close supervision of the teacher. You MUST show all of your calculations.
Part 1 Measure the total travel time for a balloon shot straight up. Perform the experiment three times and
record and average the times. Fill in the known information and calculate all of the unknown
information in the table below – you must show all of your work.
Time
1. _______s. 2. _______s. 3. ________s.
Vertical
Distance (m)
Average ________s.
1/2 way
----------
Time (s)
Velocity initial (m/s)
Velocity final (m/s)
Acceleration (m/s/s)
-9.81
-9.81
Calculations.
1
Part 2 Using the bow velocity from part 1 draw a velocity vector diagram and complete the following table
for firing the balloon at 45 degrees above the horizontal for maximum range. You MUST show all of
your calculations.
Diagram
Horizontal
Distance (m)
Vertical
1/2 way
-------------
Time (s)
Velocity initial (m/s)
Velocity final (m/s)
Acceleration (m/s/s) -------------
-9.81
-9.81
Calculations.
2
Summing up
1. Discuss the reasons for differences between the measures maximum range and the calculated
maximum range. Include your percent error in your discussion as well as the effects on the
measurements.
Actual - Calculated
x100
Percent error =
Actual
2. Under what conditions would shooting a balloon straight up allow very accurate measurements of
initial velocity (in other words how could we change the experiment to get a very accurate
measurements of initial velocity)? How would these changes affect your data?
3. Compare qualitatively (descriptive like it is cool today) and quantitatively (with numbers 42
degrees) the motion of the balloon in part B and explain the acceleration of the balloon as it travels up
with the acceleration as it travels down. You need to discus velocity and acceleration both horizontally
and vertically. This question has a high point value so spend some time on it!
3