Preview the mentos diet coke project. Check out the trailer for "The Race". You might recognize some of your friends.

Once you write a suitable experimental protocol that Dr. Don approves, you will be cleared to build and launch your rocket car. Fast workers may get this done in time to video the launch on Tuesday. If not, there will be an hour Wednesday to shoot the launch video. Thursday is set aside for the analysis.To begin the analysis, you need to make an Excel spreadsheet of time vs. distance based on data extracted from the video. Roughly, here are the key principles/challenges to keep in mind.

HINT: An easy way to access the time for each video frame is with Quicktime Player. Turn on "Show Movie Inspector" (under the Windows menu) and the time for each frame will show up as you slew through the clip. You are on your own to find a way to measure the distance traveled by the car (be sure to account for any motion of the camera and parallax).

**Calculate the energy released by the Mentos car from a video clip**. (If you are making up this lab, you can click here to download a video file suitable for video analysis). The first step is to plan your experiment. How will you shoot the video so that you can easily measure what you need? Your group needs to write down this plan in a step-by-step procedure.Once you write a suitable experimental protocol that Dr. Don approves, you will be cleared to build and launch your rocket car. Fast workers may get this done in time to video the launch on Tuesday. If not, there will be an hour Wednesday to shoot the launch video. Thursday is set aside for the analysis.To begin the analysis, you need to make an Excel spreadsheet of time vs. distance based on data extracted from the video. Roughly, here are the key principles/challenges to keep in mind.

- How are you going to measure the car's position as a function of time from the video (that is, both distance AND time). Be sure to think about this before you make your video - it will require some innovation.
- Energy (or work) is force times distance. To calculate the energy then, we need a graph of force vs. distance. The area under this graph is the energy (remember how we calculated the energy in the mousetrap spring?). Distance is relatively easy (you can measure it directly from the video) but how do you get the force? (HINT: everything you need is in the distance vs. time table).
- Do you remember any formulas involving force? How about F=ma? This formula says if you know the mass of an object and it's acceleration, you can calculate the force. Mass is easy, right? (actually, you will have to make some assumptions so be sure to think it through). But how do we get a handle on acceleration?
- Acceleration is the rate of change of velocity. So if we knew how the velocity of the car was changing, we could calculate accelerations. Can you measure the velocity of your car from the video data as a function of time? How?
- Any good experiment includes a prediction for what you expect to happen (it's called a "hypothesis"). Can you sketch a graph of velocity as a function of time that you expect to observe? How about acceleration vs. time?
- To summarize, you will start with a graph of distance vs. time using data taken directly from the video. From this, you will derive a second graph of velocity vs. time. From the velocity graph, you can derive an acceleration graph. Once you have acceleration as a function of time, multiplying by the mass gives you a force. Finally, graphing the force vs. distance (NOT time) and summing the areas under the graph ("integrating") will give you the energy, just like you did for the mousetrap spring.

HINT: An easy way to access the time for each video frame is with Quicktime Player. Turn on "Show Movie Inspector" (under the Windows menu) and the time for each frame will show up as you slew through the clip. You are on your own to find a way to measure the distance traveled by the car (be sure to account for any motion of the camera and parallax).