Group+2

Christi Joyner; Tracy Neal; Valerie Stover Matt Kinnaird, John Scarfpin Ashlee Tetreault Amber Teeters
 * Names of Experiment Designers ** (those that design the experiment):
 * Names of the Peer Reviewers ** (collaborating group):
 * Names of the Investigators ** (those that will conduct the experiment):

Part 1. Design of a projectile motion experiment
A. What is your hypothesis? (You will test one variable with and without air resistance.) Using a baseball as the projectile, as speed increases, range will also increase.

B. Create a step by step experimental protocol to test your hypothesis using the applet at: @http://phet.colorado.edu/sims/projectile-motion/projectile-motion_en.html 1. Choose "baseball". 2. The angle remains at 80 degrees, mass is 0.145 kg, and diameter is 0.074 m, no air resistance, leave speed at 18 m/s initially. 3. Click Fire and observe. 4. Record range in data table. 5. Click Erase 6. Increase speed to 20 m/s (by an increase of 2 m/s) for each trial. Increase for a total of 5 trials. Be sure to record the range after each trial.

- What are the independent vs. the dependent variables in the experiment? independent variable: Speed m/s dependent variable: range m - How will you test air resistance in the experiment after testing your initial variable? How do the two variables interact? Keep the speed constant and add air resistance; when you add both variables, the range changes and is decreased - How many repetitions will you need to carry out within the experiment? 5 - What data will you collect and how will you collect it? Speed and range; in a data table
 * In your experimental protocol you may wish to ask yourself the following: **

C. Experimental Protocol:

1. Choose "baseball".

2. The angle remains at 80 degrees, mass is 0.145 kg, and diameter is 0.074 m, no air resistance, leave speed at 18 m/s initially.

3. Click Fire and observe.

4. Record range (at the top of the page) in data table.

5. Click Erase

6. Increase speed to 20 m/s (by an increase of 2 m/s) for each trial. Increase for a total of 5 trials. Be sure to record the range after each trial.
 * Speed m/s || Range m ||
 * 18 || 11.6 ||
 * 20 || 14.3 ||
 * 22 || 17.3 ||
 * 24 || 20.5 ||
 * 26 || 24.0 ||

Part 2. Peer review of experimental protocol.
A. The peer review group should enter their comments regarding the experimental protocol below. They should ask themselves: - Is the hypothesis being careful tested? - Is the protocol easy to follow? Is it sequential? - Can the independent and dependent variables be easily identified and measured?


 * Peer Review: **

This is a good experiment. I would only change two things. In step 4 I would indicate to use the measuring tool to find the range and I would add a data table to step 6 for the students to complete.

B. The experimental designers should now alter the experimental protocol based upon peer review.

Part 3. Conduct the experiment.
Now a different group will conduct the actual experiment using: @http://phet.colorado.edu/sims/projectile-motion/projectile-motion_en.html

A. The investigational group should try to follow the protocol as written. Changes can be made if the protocol is not clear.

B. Data should be entered below. Tables for data can be made using the wiki. Simple graphs can be created in MS Office if time allows.

Entered data in table above.



Part 4. Results and Discussion
The investigational group should now write a short paragraph using scientific writing to explain their findings. Findings will be discussed with the group at large.

As we changed the speed of the baseball the range increased. The independent variable was the speed of the baseball and the range was the dependent variable in this experiment. The constants were the baseball and the position/angle of the canon. We changed the speed for 5 trials and this allowed us to see any visible patterns. The hypothesis was proven to be correct in this experiment.

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