Physics in Action

1. Physics in Action Kinematics = the study of motion

2. Physics in Action p13 • Project rationale • Read pages 128-129 • Record 2 questions about the project (what do you need to know to get started) and 2 comments (summarize what the project is about) on the handout as you read. (You need at least 2 each)

3. Which activities are considered sports? p14 • Make this T-chart • Define the word “sport” …

4. Sports Casting • Write a script for a 30 second sport voice-over (the sport is your choice) • Don’t forget to introduce yourselves… • Explain why/how your sport fits the definition for “sport” • Describe specific actions/plays that demonstrate motion and the following physics words:(used correctly!) in your script: speed, velocity, acceleration, and safety

5. Practice your presentation! Everyone must play an active role for creditPresentations are TODAY! • Watch the other groups present and think about what parts of the presentations you like best. • Reflection (on the back side): describe at least 3 ways that you could improve your presentation for next time (YES! There WILL BE a next time!)

6. p14 Anyone want to read their sports script? • Watch/listen to the other groups present and think about what parts of the presentations you like best. • Reflection (on the back side): describe at least 3 ways that you could improve your presentation for next time (YES! There WILL BE a next time!)

7. Speed – Day 1How do we measure speed? • Record your answer to the following: What is speed? How do we measure speed? What units are speeds measured in? How do you know? • Share with your lab partners Groups are ASSIGNED (no switching!) p15

8. Dune Buggy Brigade • get your assigned equipment box and follow the instructions. • When you are finished, make sure all the equipment is returned IN WORKING ORDER to the box and put the box back on your lab bench • Each person must record everything in their own notebook • Measure the speed of your car using only the contents of your box (car, tape measure, stop watch) • You have 10 minutes to do this and return to graph your data

9. More directions… p15 • Record your procedure in your notebook. • Record your data (including units!) • Make a distance vs time graph (use a graph stamp in the front of the room to make a grid in your notebook BEFORE graphing) distance time

10. Calculate the speed of your car • Explain how you calculated the speed of your dune buggy • Optional: if you finish and there is enough time, do the same steps for a second car (get the new car from Mrs. D) p15

11. Presentations • Record what your group did on a white board to present to the class p15

12. Our Model for Speed (so far…)Driving Question: How can we describe motion? 1.) Speed is the distance over the time s=d/t 2.) Speed can be measured in mi/hrft/min in/sec m/sec 3.) Use metric! m/sec 4.) Velocity is the speed AND direction of the object v=d/t (positive velocity is forward; negative velocity is backwards) p16

13. Questions p15 • Group X measured the time it took the car to travel 1 meter and calculated the speed as 2 m/s. Group Y measured the distance that the car went in 10 seconds and also calculated a speed of 2 m/s. Which method do you think is better? Why? • What is the difference between speed and velocity? Explain how 2 cars could have the same speed, but different velocities.

14. Speed 2Record these answers in your notebook p15 3.) Group K measured the speed of their car as 4 meters/second. Group J measured the speed of the same car as 12 feet/second. Explain which speed is better for physics class. 4.) Explain how the wrong units can be “fixed”. Did both groups come up with the same answer?

15. More ways to calculate speed… • Complete Worksheet #1 (talk each problem out with your group and make your best guess – consider this a pretest of what you can do) • Get your work stamped when you finish each panel • Finish pages 14-17 • Turn in your script (Benchmark #1) p17

16. Review

18. Worksheet 1 answers 26.) 1m/0.5s = 2 m/s 27.) 8m/4s = 2m/s 28.) 50m/10s = 5 m/s 29.) 8km/h x 1 h = 8 km 30.) 10m/s x 40s = 400 m 31.) 10km/h x 0.5h = 5 km Next time question…30km WHY?

19. Using a motion sensor p17 • What does a graph of motion away from the sensor look like? Make your prediction in one color, and then use a second color (or a highlighter) to show the actual graph p o s i t i o n time

20. Using a motion sensor p17 • What does a graph of motion towards the sensor look like? Make your prediction in one color, and then use a second color (or a highlighter) to show the actual graph • What if the object goes slower? Faster? p o s i t i o n time

21. Rest, Stop, and Motion p18 • Define the following words And make a position graph and label the words on the correct location of the graph • Rest • Motion • Uniform motion p o s i t i o n time

22. The rate at which position changes is called velocity • Velocity = distance/time • V=d/t • What is the average velocity of a marathon runner who runs 26 miles in 3 hours and 15 minutes?

23. Uniform motion • In uniform motion the speed is constant. • But so is the direction of motion • In other words, an object in uniform motion has constant velocity • The velocity of an object is its speedand direction

24. Can two cars moving with the same speed collide? Explain • Can two cars moving with the same velocity collide? Explain

25. Acceleration • Accelerated motion occurs when the velocity of an object is changing • If the velocity changes at a constant rate, the motion is called uniform accelerated motion. • The rate at which velocity changes is called acceleration • Acceleration = change in velocity change in time • A = v/t

26. Accelerated motion includes: • Speeding up (acceleration) • Slowing down (deceleration) • Changing direction (so an object with constant speed can be acceleration if it is going in a circle because the direction is always changing) (also acceleration)

27. Make up a story to go with each graph p18

28. Now let’s add to our model for speedDriving Question: How can we describe motion? 5.) When you make a position graph for constant (uniform motion) the result is a straight line 6.) The slope of the line is velocity 7.) Slow motion has a gradual slope 8.) Fast motion has a steep slope 9.) If the speed is changing continuously, then the graph is a curve (acceleration) p16

29. Worksheet 2 p19

30. Worksheet 2 p19 • Label Motion graphs • Acceleration problems (32-37) Get your paper stamped on each side when finished Did you Finish your script? Do you need to make notebook revisions this week?

31. Worksheet 2 answersCheck your work 32.) (100km/h)/10s = 10 km/h/s 33.) (40km/h)/10s = 4 km/h/s 34.) (25 m/s)/5s = 5 m/s2 35.) 2m/s2 x 10s = 20 m/s 36.) 5 m/s2 x 3s = 15 m/s 37.a) C, A=B b) C, A=B c) A,C,B

32. Moving Man Simulation p20 • Google phet • Click on “play sims” • Click on “physics” • Click on “motion” • Click on “Moving Man” • Follow the directions on the handout to complete each part • Get a stamp when you are finished • Make sure your computer is OFF before you close the lid

33. Now let’s do Worksheet #3Use 2 colored pencils…one to show your prediction, and one to show the final answer p21

36. Let’s add what we learned about velocity graphs to our Model for speed 10.) Velocity can be positive (forward) or negative (backward) so our y-axis must be modified (area below the x-axis) 11.) Constant motion=constant velocity which is a straight line (look like stair steps) 12.) At the present time we are ignoring how/when objects speed up or slow down p16

37. Worksheet 3 Answers • Practice exercises 1.) distance = speed x time = 340 m/s x 2.6 seconds = 884 meters 2.) velocity = distance/time = 1000m/7.045s = 141.9 m/s

38. Now let’s look at another way to view motion… • Motion maps • Read the article (worksheet 4) • Complete worksheet • Finish pages 18-22 for notebook check p22

39. What would the motion map for each object look like? • A ball rolling slowly • A ball rolling fast • A ball that speeds up • A ball that slows down • A ball that rolls fast, hits the wall and bounces back slowly • A student who walks in the room, stands around for 3 seconds, and then leaves the room p22

40. Now add motion maps to our Model of Speed p16 13.) Objects moving slowly are represented by short arrows. Objects moving faster are represented by longer arrows. 14.) Arrows point in the direction of motion 15.) Objects that stop moving leave a dot for each period of time that they are motionless.

41. Worksheet 4 answers 1.a) the car is moving at constant speed b) Speeds up then slows down 2.a) speeds up constant speed b) constant speed slows down 3.) d=vt=(350ft/s)(20s)=7000 ft p22

42. More worksheet 4 answers p22 4.a) v=d/t=215mi/4.5h=48 mi/h b.) probably 48 mi/h, maybe faster or slower 5.) v=d/t=5mi/0.25h=20 mi/h 6.a) forward at constant speed, then at rest b.) forward fast, rests, backward slow c.) forward constant slow, constant fast d.) speeds up

43. Quiz 1 p24 • NO PHONES! Only calculators allowed during the test. • Answer each question the best you can • Turn in your quiz • Worksheet 5 – try graph #1-2 AND do the back (p154) 1-3, 6-10

44. p23 Ave vs instant speed • Watch the video and answer these questions: Instantaneous means: Average speed = • 30 km/0.5 hr = 180 km/3 hr = • 70 km/1 hr = • 0 km/0.5 hr = • 80 km/1 hr = • If your average speed to drive home is 20mph, why will your instantaneous speed be different? Give 2 examples

45. p25 p o s i t i o n time • Draw on the graph to show speeding up motion. Label it acceleration. • Draw on the graph to show slowing down motion. Label it deceleration.

46. REVIEW Position graphs • Show relationship between distance and time • Straight line=constant motion • Curve shows acceleration • Slope =rise/run • Velocity=d/t p25

47. REVIEW Velocity graphs • Show relationship between velocity and time • Horizontal line=constant motion • Sloped line=changing motion • Area under the curve=displacement • D=vt • A=v/t

48. Acceleration graph • Shows the relationship between acceleration and time • Area under the curve is velocity • V=at • D=1/2 at2

49. Standing still(not moving or at rest)

50. Constant velocity (forward or backward)