Projectile Motion

1
Projectile Motion

• Predicting Testing Variables That Affect Range
• (Straw Rockets).

2
Lab Description

• Students are asked to define range in their own
  words
• Students are presented the materials and show how
  the rockets are launched
• Students are asked to make a list of variables
  that might affect the range of the straw rocket
• Students are then asked to devise a method for
  testing the variables and record all results
• Students are asked to write a one-page summary of
  their procedure and conclusions

3
Lab Description cont.

• List of supplies
• Straws
• Clay
• Note cards
• Hot glue guns scissors
• Triple beam balances meter sticks
• Launch apparatus

4
Goals general goals

• Students will test their understanding of range
  as related to projectile motion
• Students will use the Scientific Process to
  develop an experiment with procedure and test
  variables
• Students will develop a correct understanding of
  range for projectile motion

5
How would I use this in class

• Introductory guided inquiry-based lab
• Used to introduce projectile motion
• Used as a student developed experiment

6
Standards Frameworks

• Physical Science
• Strand Physics
• P.6.PS.1 Analyze how force affects motion
  (one-dimension (linear) and two-dimension
  (projectile and rotational))
• P.6.PS.7 Design and conduct investigations
  demonstrating Newtons first law of motion
• P.6.PS.8 Design and conduct investigations
  demonstrating Newtons second law of motion
• P.6.PS.9 Design and conduct investigations
  demonstrating Newtons third law of motion
• Strand Nature of Science
• NS.10.PS.1 - Develop and explain the appropriate
  procedure, controls, and variables (dependent and
  independent) in scientific experimentation
• NS.10.PS.2 - Research and apply appropriate
  safety precautions (refer to ADE Guidelines) when
  designing and/or conducting scientific
  investigations
• NS.10.PS.3 Identify sources of bias that could
  affect experimental outcome
• NS.10.PS.4 - Gather and analyze data using
  appropriate summary statistics
• NS.10.PS.5 - Formulate valid conclusions without
  bias
• NS.10.PS.6 Communicate experimental results
  using appropriate reports, figures, and tables
• See http//arkansased.org/educators/curriculum/fra
  meworks.htmlscience for more details.

7
Adaptations and Q(s)

• Hit the target competition students will use
  their knowledge gained in this activity to
  compete to hit a target for bonus points on an
  exam. Time limit for building rocket ad limit on
  number of launches.
• Mathematical model of projectile motion (PLC
  activity with math teacher) students will use
  data collected in the physics class to graph and
  develop a mathematical model of projectile
  motion.

8
Spring Presentation Slides

• The following slides are the results of
  performing the experiment with my students in the
  classroom.
• This is my Spring 2011 MSP follow-up
  presentation.

9
Range

• Students were asked to write a definition of
  range for their straw rockets.
• Sample Definitions
• Range is the distance the rocket will travel.
• Range is how far my rocket will fly.
• The distance in the air my rockets moves is
  called range.

10
Variable Predictions

• Students were asked to make predictions about the
  variables that would affect the range of their
  straw rockets.
• Sample list of variables chosen by the students
• Length of the straw
• Amount of clay in the nosecone
• How high I lift the launcher
• The angle of the launcher
• The design of the fins
• Wind

11
Testing Your Predictions

• Students were asked to test their predictions and
  organize the results in a table.
• Sample table for angle of launcher

Angle (Degrees) Distance (m)
30 8.95
35 9.32
40 9.76
45 10.05
50 9.82
60 9.12
12

• Sample table for length of straw with 15 grams of
  clay for nosecone

Length of Straw (m) Distance (m)
.30 8.54
.27 8.46
.24 8.21
.21 8.05
.18 7.62
13
Conclusion Statements

• Students were asked to make conclusion statements
  about the variables they choose to test.
• The length of the straw matters. The shorter
  the straw the more wobbly the path. So the
  shorter the distance.
• The angle makes a big difference. The longest
  distance was around 45 degrees.

14
Student reactions to the lab

• Making the rockets was so much fun!
• I liked when one stuck to the ceiling.
• It was cool!
• I liked changing the angle and trying different
  heights for the launcher.

15
Teaching Moments

• One group of students tried gluing on 6 or 7
  pairs of fins and found the weight made a bigger
  difference than the number and size of the fins.
• One group was trying to test if the air made a
  difference. I suggested taping different size
  note cards to the nosecone.

16
Future Changes

• Allow two days for students to test all of the
  variables they chose.
• Combine all the data into one chart.
• Have the students look for trends in the data.