1. AP Physics ST Frames of Reference Graphs of Motion nasa.gov

2. Frames of Reference Frame of Reference – Point of view. Most COMMON fixed frame of reference… – Surface of the earth. Others??? g33kscorner.blogspot.com

3. Frames of Reference Who’s moving?? The International Space Station (ISS) relative to Earth or Earth relative to the ISS? theregister.co.uk

4. Frames of Reference Earth –based view of space shuttle and ISS. wunderground.com

5. Frames of Reference ISS–based view of space shuttle and Earth. chamorrobible.org

6. Frames of Reference Cartesian Coordinate System – Plotting axes 1 dimensional motion – Motion in one direction at one time – Forward OR backward, but not forward AND backward at same time. – Up OR down but not up AND down at same time. thelivingprophecy.com

7. Frames of Reference 2 dimensional motion – Motion in two directions at one time. – Forward AND up at same time. – Backward AND down at same time. 3 dimensional motion – Motion in three directions at one time. – Forward AND up AND out at same time. – Backward AND down AND in at same time. rbrundritt.wordpress.com outreach.phas.ubc.ca

8. Frames of Reference Unit vector axes system – Directional axes. Unit vector – Vector of magnitude 1 Doesn’t affect the magnitude of the vector it describes. – Shows direction only! iphone4gapp.net

9. Motion Graphs “A picture is worth a thousand words.” – December 1984, Afghanistan; 12 year old refugee girl fleeing to Pakistan to escape the war with Soviet Union. – This photo has “…come to symbolize the plight and the pain and the strength of the Afghan people.” (National Geographic, June 1985) bloodwoodtree.org

10. Motion Graphs “…a thousand words?”… – Anger/rage – Pain – Strength – Vengeance – Sadness – Rebellion/fire – Attitude – Traveled – Alone… bloodwoodtree.org

11. Motion Graphs Her name is Sharbat Gula, which means "sweetwater flower girl" in Pashtu, the language of her Pashtun tribe (29 yrs old) Twenty-three years of war, 1.5 million killed, 3.5 million refugees. This picture reflects the story of Afghanistan in the past quarter century. lewebpedagogique.com

12. Motion Graphs Like photographs “motion-graphs” provide just about every characteristic of motion. Acceleration Curve of Space Shuttle from Launch to Engine Shut-Down

13. Motion Graphs 5 major points regarding motion graphs: 1.Direction of slope 2.Rate (pitch) 3.Slope of a line on a d-t graph. 4.Slope of a line on a v-t graph. 5.Moving “forwards and backwards” between graphs.

14. Motion Graphs - Direction of Slope As applied to a d-t, v-t or a-t graph a positive, negative or zero slope describe DIRECTION! dickson-physics.wikispaces.com

15. Motion Graphs – Rate (pitch) Characteristics of motion are described by the “rate of change” of displacement, velocity and acceleration RATE – – Time it takes for displacement, velocity or acceleration to change from one value to another.

16. Motion Graphs – Rate (pitch) As applied to displacement… – Large amounts of distance covered in 5 s = a high rate of change of displacement. – Small amounts of distance covered in 5 s = low rate of change of displacement. learkni.tk

17. Motion Graphs – Rate (pitch) HIGH rates of change = steeply pitched slopes LOW rates of change = shallow pitched slopes learkni.tk

18. Motion Graphs – Rate (pitch) As applied to velocity… – Large changes of velocity in 5 s = a high rate of change of velocity. – Small changes of velocity in 5 s = low rate of change of velocity. learkni.tk

19. Motion Graphs – Rate (pitch) HIGH rates of change = steeply pitched slopes LOW rates of change = shallow pitched slopes learkni.tk

20. Motion Graphs – Rate (pitch) As applied to acceleration… – This course will focus largely on constant acceleration… meaning there will be no “rate of change of acceleration.” Zero-slope indicates there is no rate of change; because there is no change. learkni.tk

21. Motion Graphs – d-t Graphs Displacement vs. Time Slope of a line on a d-t graph shows velocity; magnitude and direction. webs.mn.catholic.edu

22. Motion Graphs – d-t Graphs The slope of a tangent line is known as an instantaneous velocity. webs.mn.catholic.edu

23. Motion Graphs – v-t Graphs Velocity vs. Time Slope of a line on a v-t graph shows acceleration; magnitude and direction. webs.mn.catholic.edu

24. Motion Graphs – “To-From” Successful interpretation of motion requires knowing – “slope of a line on a d-t graph shows velocity” – “slope of a line on a v-t graphs shows acceleration” FORWARDS AND BACKWARDS!!

25. Motion Graphs – “To-From” FORWARD: – From d-t to v-t:slope of a line on a d-t graph shows velocity – From v-t to a-t:slope of a line on a v-t graph shows acceleration BACKWARD: – From a-t to v-t: acceleration points came from the slope of a line on a v-t graph – From v-t to d-t:velocity points came from the slope of a line on d-t graph

26. Motion Graphs – HINTS 1.Considering ONLY constant acceleration – V-t graphs will have only straight lines. – A-t graphs will have zero slope 2.If acceleration is present – D-t graphs will be “curvey” 3.If a-t graph represents non-zero acceleration – V-t graph will have a diagonally sloping line originating above, at or below the zero axis; known as the initial condition. – D-t graph MUST correspond to initial condition.

27. Lesson Summary

29. Example’s In-class examples: – Challenge-graphs conducted on overhead. – Graph-construction conducted on worksheets.