Describing Motion

1. Describing Motion

2. Warm Up

3. Test Review • Test Review • Test 3 = Questions 1,2,11,12,13,14,15,16 • 8 Total • 12.5 points a piece • Test 4 = All the other question • 17 Total • 5.8 points a piece

4. Speed, Velocity, Acceleration • “Find Someone Who” can tell you what speed, velocity, and acceleration are. • You must locate three different peers to tell you what they think these terms mean and record the answers in the “What we think” row of the document. • You are expected to answer as well as ask. • It’s OK to be wrong but your must have and answer • The student who answers needs to sign his/her name next to their answer. • 2 minute time limit per word

5. Speed, Velocity, Acceleration • Now list an “A” for agree or a “D” for disagree next to the definitions • Turn to your shoulder partner and explain why they agree or disagree with the definitions. • You have 2 ½ minutes • GO

6. Speed, Velocity, Acceleration • Update your handouts by recording the scientific definitions of speed, velocity, and acceleration in the “What We Know” row of their handouts. • The PowerPoint will instruct you to record examples as they complete their notes on the handout.

7. Speed • The distance an object travels in a certain amount of time. • Average speed – Total distance divided by total time • Constant speed - Speed that does not change • On your paper, describe an example of an object at a constant speed.

8. What is the formula for calculating speed? Speed equals distance divided by time.

9. Let’s Practice Calculating Speed • On the side of your paper, calculate this problem. Make sure you show all work! A football field is about 100 meters long. If it takes a person 20 seconds to run its length, how fast was the football player running?

10. Check Your Work A football field is about 100 meters long. If it takes a person 20 seconds to run its length, how fast was the football player running? • Speed = Distance ÷ Time • Speed = 100 m ÷ 20 s • Speed = 5m/s Remember to label the UNITS!!

11. Velocity • An object’s speed and direction at a given time • The wind is blowing 65 km/hr from the North. • On your paper, describe an example of velocity.

12. Acceleration • A change in the direction or speed (velocity) of an object over time – which may be: • A change in speed • Starting • Stopping • Speeding up (positive acceleration) • Slowing down (negative acceleration) • A change in direction • Acceleration is caused by unbalanced forces. • On your paper, describe an example of an object accelerating.

13. Speed, Velocity, Acceleration • How does your “What We Think” section compare to your “What We Know” section? • Does anyone notice any differences in the meaning of the three terms? Explain. • Speed is distance/time, velocity is speed with a direction, and acceleration is a change in speed and/or direction.

14. Speed, Velocity, Acceleration • The terms we have noted are extremely important in our upcoming unit of study. Be prepared to refer back to them often. • Highlight, circle, or underline the key points

15. Warm Up

16. Video • http://www.youtube.com/watch?v=DRb5PSxJerM

17. Calculating and Graphing Speed • Title the next blank page Calculating and Graphing Speed You are going to draw 5 easy graph and interpret the speed

18. Interpret the Graph Below: The graph shows an object which is not moving (at rest). The distance stays the same as time goes by because it is not moving.

19. Interpret the Graph Below: The graph showsthat the objects distance increases as time passes.The object is moving and so it has velocity. The straight line shows it is a constant (not changing).

20. Interpret the Graph Below: Just like the previous graph, this graph shows an object moving with constant velocity.

21. Interpret the Graph Below: The curve, in the graph, shows that the object’s velocity is changing as time passes. This is acceleration.

22. Interpret the Graph Below: In the first part of the graph, the object is moving with constant velocity. In the second part of the graph, the object is at rest (not moving). In the thirdpart, the object is again moving with constant velocity.

23. Calculating and Graphing Speed • LAB instructions • Everyone is always recording • Group Roles (you will rotate jobs) • Roller • Timer 1 • Timer 2 • Timer 3 • Director • Says Start and Stop • Is in Charge

24. Warm Up

25. Calculating and Graphing Speed • Continue the lab • Group Roles (you will rotate jobs) • Roller • Timer 1 • Timer 2 • Timer 3 • Director • When you are finished sit back at your desk and complete the graph and the questions • Work together • Turn in when you are finished • Use COLOR on the graph

26. Warm Up • Directions: • 1. Read the following scenario. • 2. Calculate the average speed. • 3. Briefly describe all points of acceleration and explain. • A female cheetah left her cubs to hunt for food. She sprinted 30 m away from her den in two seconds. Next, she turned around and traveled 10 meters back toward her den in three seconds. She suddenly stopped and listened intently for two seconds. Then, she traveled 40 meters away from her den in four seconds.

27. Card Sort • With your face partner, sort the cards into 3 groups

28. Story Graphs • With your groups, write a 10 sentence story using 2 of the four graphs. • Your story must include: • The average speed • Acceleration • Main Character • Plot • Be creative • 10 pictures • Use two iPad • Be prepared to share

29. Warm Up • Write Tug of War on your warm up • Open Tug of War Handout in eBackpack

30. Warm Up

31. Change the Motion of an Object • Open Change the Motion of an Object in ebackpack • You will answer the questions ON THE FIRST PAGE as you complete the lab • Using the object that I give you make it accelerate AT YOUR DESK!!!!!!!!!!! • Make it stop, start, speed up, slow down, and change direction

32. Volunteer to Share • Pass out the laminated paper

33. Change the Motion of an Object • With your should partner look at the handout. • Describe the motion of the object. • Such as: left, right, up, down • Then explain to your partner why your think the object will move in a certain direction. • Use words like: balanced, unbalanced, force, motion and acceleration

34. Notes • Volunteer to share • Now you are going to start filling out the rest of the paper from ebackpack • Copy what is in yellow and include a quick picture

35. Motion • A change in the position of an object • Caused by force (a push or pull)

36. Force • A push or pull on an object • Measured in units called newtons (N) • Measured with a spring scale • Forces act in pairs Types of Force: (pick two) • gravity • electric • magnetic • friction • centripetal

37. Balanced Forces • When all the forces acting on an object are equal (net force is zero) • Balanced forces do not cause a change in motion. • Balanced forces can change the physical properties of an object without changing its motion. • In your notes, describe an example of a balanced force.

38. How Can Balanced Forces Affect Objects? • Cause the shape of an object to change without changing its motion • Cause an object at rest to stay at rest or an object in motion to stay in motion (inertia) • Cause an object moving at a constant speed to continue at a constant speed • In your notes, describe an example of a balanced force affecting an object.

39. Inertia • An object at rest will remain at rest until acted upon by an unbalanced force. • An object in motion will remain in motion until acted upon by an unbalanced force. • When all forces acting on an object are equal (balanced)

40. Unbalanced Forces • When all the forces acting on an object are not equal • The forces can be in the same direction or in opposite directions. • Unbalanced forces cause a change in motion. • In your notes, describe an example of an unbalanced force.

41. How Can Unbalanced Forces Affect Objects? • Acceleration is caused by unbalanced forces: • slow down • speed up • stop • start • change direction • change shape • In your notes, describe an example of an unbalanced force affecting an object.

42. Net Force • The total of all forces acting on an object: • Forces in the same direction are added. • The object will move in the direction of the force. • Forces in opposite directions are subtracted. • An object will move in the direction of the greater force. Balanced forces do not cause a change in motion.

43. Warm Up

44. Open your notes from yesterday and prepare to finish taking notes • Copy what is in YELLOWand include a quick picture

45. Calculating Net Force 1 10 N 30 N http://commons.wikimedia.org/wiki/File:Jack-in-the-box.jpg A child was playing with a jack in the box. The lid pushed down with 10 N of force, while the spring pushed up with 30 N of force. What is the net force applied by the spring? In your notes, calculate the net force and show all of your work.

46. Check Your Answer 10 N 30 N http://commons.wikimedia.org/wiki/File:Jack-in-the-box.jpg A child was playing with a jack in the box. The lid pushed down with 10 N of force, while the spring pushed up with 30 N of force. What is the net force applied by the spring? 30 N to the right + 10 N to the right = 40 N to the right

47. Calculating Net Force 2 Tug of War Game 30 N 50 N Two competitors are playing tug of war. What is the net force? Which direction will the rope move? In your note, calculate the net force and show all of your work.

48. Check Your Answer Tug of War Game 50 N 30 N Two competitors are playing tug of war. What is the net force? Which direction will the rope move? 50 N to the right – 30 N to the left = 20 N to the right

49. Force Arrows • Open the Data Sheet in ebackpack • You are completing the first half of the first page • You have 5 minutes to rotate around the room and find three DIFFERENT partners. You will combine arrows. You decide which direction you want them to turn. Fill in the chart

50. Mass and Weight • Mass is the amount of stuff (matter) in an object. • The mass of an object will remain the same anywhere in the universe. • Mass is measured in grams or kilograms.