1.  Scaling a car crash

2. STEM ACTIVITY #1  Objective: You will use a motion sensor to gather data to investigate the relationship between stopping force and time of impact.  Materials : motion sensor, skateboard, wall, bathroom scale, Excel spreadsheet  Using Data Studio Software, create two collisions into a wall. One will bring you to a slow stop, and the other should employ a moment of collision that models a faster stop. Create a velocity time graph for each and replicate these into your lab books. You may screen shot and print these ( 3-4 to a page please!) Play around until the graphs have a look that makes sense. To hit the wall at a consistent speed, use the bathroom scale method of applying force. Remember, the “push” force is not the same as the “stopping” force. Sample collision m/s s 1.Notice that we are interested in the part of the graph where the wall applies the impulse (i.e. takes the velocity from some value to zero). 2.The motion sensor chooses your direction as negative. It is truly arbitrary 3.Using the mouse, zoom in on your graph to enlarge the portion of interest

3. Data Portion s1.The slope of your graph is m/s /s which is acceleration 2.Slope time mass = F! 3.Keep track of the time at which the force occurs 1. Create a table to keep track of the key variables that apply to impulse 2. Calculate the Force required to stop you in your 2 scenarios using your knowledge of Impulses. Show your equation and work. 3.Calculate the instantaneous force from three points on your graph. 4.Create a F x t graph in your lab book from step #3, and use it to mathematically calculate the Impulse applied to stop you in these scenarios. m/s a a

4. Conclusion