1. 76 Speed and Collisions

2. LIMITED LICENSE TO MODIFY. These PowerPoint® slides may be modified only by teachers currently teaching the SEPUP course to customize the unit to match their students’ learning levels or to insert additional teaching aides. Modified slides may be used only by the modifying teacher in his or her classroom, or shared with other teachers of SEPUP within the teacher’s school district, with these same restrictions. Modified slides may not be taken out of the classroom or distributed to any non-student person or organization. Except for use with students in the classroom, modified slides may not be published in printed or electronic form, including posting on the Internet. Only text may be modified: photographs and illustrations on the slides may not be modified in any way except to change their size. DISCLAIMER OF WARRANTY. THE REGENTS OF THE UNIVERSITY OF CALIFORNIA (“University”) MAKE NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. University will not be liable for any costs, damages, fees or other liability, nor for any direct, indirect, special, incidental or consequential damages (including lost profits) with respect to any claims by the purchaser or user of SEPUP or any third party on account of or arising from the use or modifications to the slides. Client acknowledges and accepts that University services are provided on an as-is basis. Copyright © 2015 The Regents of the University of California. All rights reserved. Header photo: Sam Howzit | Flickr Creative Commons Slide Design: Shaun Wegscheid | Fonts: Arial, Kalinga Title slide photo: Jean Scheijen | FreeImages.com

3. 76 Speed and Collisions Key Vocabulary acceleration force speed tested variable

4. 76 Speed and Collisions Force Write down the first five things that come to your mind when you hear this word.

5. 76 Speed and Collisions What might you observe when a force is acting on an object? Share your thoughts with the class.

6. 76 Speed and Collisions Read the introduction and look for key ideas The force with which this car was hit was large, but the time it took to collide was short.

7. 76 Speed and Collisions Does vehicle speed affect the forces involved in a collision?

8. 76 Speed and Collisions Review the procedure What are the variables in this experiment? What is the tested variable?

9. 76 Speed and Collisions Complete the procedure Copy the table in your notebook to record your data.

10. 76 Speed and Collisions Report your average distance values for each speed

11. 76 Speed and Collisions What patterns do your data show? Share your answer with the class.

12. 76 Speed and Collisions Analysis question 1 How does the speed of the cart affect how far the block moves?

13. 76 Speed and Collisions Analysis question 2 Why do you think release height has this effect?

14. 76 Speed and Collisions Analysis question 3 What part(s) of the experiment’s design: a.increase your confidence in the data? b.decrease your confidence in the data?

15. 76 Speed and Collisions Analysis question 4 When a car crashes, do you think its speed can make a difference in the amount of damage done? Explain, using evidence from this investigation.

16. 76 Speed and Collisions Force Not only does the car apply a force to the block, but the block applies a force to the car.

17. 76 Speed and Collisions Does vehicle speed affect the forces involved in a collision?

18. 76 Speed and Collisions Key vocabulary definitions Acceleration - The rate at which an object changes speed and/or direction. Force - A push or pull. Speed - The rate at which an object moves, equal to the distance traveled per time interval.

19. 76 Speed and Collisions Key vocabulary definitions Tested variable - A variable that is changed in a systematic way in an experiment or investigation in order to determine its effect.