ScienceScene (The MAPs Co.)

1. To the MAPs Team's Presentation of Motion Dr. M. H. Suckley & Mr. P. A. Klozik Email: MAP@ScienceScene.com http://www.ScienceScene.com (The MAPs Co.)

2. MAP Team Motion

3. Motion I. Introduction II. Newton’s First Law III. Newton’s Second Law IV. Newton’s Third Law

4. Motion I. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . 3 II. Newton’s First Law . . . . . . . . . . . . . . . . . . . . 4 A. Motion 1. Measuring the Velocity of Various Objects. . . . . 6 2. Observing Motion of a Toy Car. . . . . . . . . . . . . . 5 B. Inertia 1. Fundamentals . . . . . . . . . . . . . . . . . . . . . . . 9 2. Using Your Marbles. . . . . . . . . . . . . . . . . . . 10 3. FUN With Inertia. . . . . . . . . . . . . . . . . . . . . 10

5. Motion III. Newton’s Second Law . . . . . . . . . . . . . . . . . . . 11 A. Acceleration (change in velocity) 1. Observing Acceleration. . . . . . . . . . . . . . . . . . .12 2. Acceleration A More Complete Picture . . . . . . . . 13 B. Fundamentals of Force 1. Observing Forces (using the “Gizmo”). . . . . . . . . 14 2. Finding The Forces. . . . . . . . . . . . . . . . . . . . . . 15 3. Types of Force. . . . . . . . . . . . . . . . . . . . . . . . . . 24 4. Forces in a Collision . . . . . . . . . . . . . . . . . . . . . 26 5. The Falling Cup . . . . . . . . . . . . . . . . . . . . . . . . 27 C. The Affect of Mass on Acceleration . . . . . . 28

6. Motion IV. Newton’s Third Law .. . . . . . . . . . . . . . . . 29 A. Equal and Opposite. . . . . . . . . . . . . . . . . . .30 B. Equal and Opposite Another Look . . . . . . . . . 31 C. Making Formulas Out of Words . . . . . . . . . . . . 33

8. Thank You! We Had A Great Time

9. Michigan Benchmarks for Motion Prerequisite Skill • Describe or compare motions of common objects in terms of speed and direction. • Key concepts: Words--east, west, north, south, right, left, up, down. Speed words--fast, slow, faster, slower. • Real- world contexts: Motions of familiar objects in two dimensions, including rolling or thrown balls, wheeled vehicles, sliding objects. forces • Describe how forces (pushes or pulls) are needed to speed up, slow down, stop, or change the direction of a moving object. • Key concepts: Changes in motion--speeding up, slowing down, turning. Common forces--push, pull, friction, gravity. Size of change is related to strength of push or pull. • Real- world contexts: Playing ball, moving chairs, sliding objects. V = d / t • Qualitative describe and compare motion in two dimensions. • Key concepts: Two- dimensional motion--up, down, curved path. Speed, direction, change in speed, change in direction. • Real- world contexts: Objects in motion, such as thrown balls, roller coasters, cars on hills, airplanes. F = m x a 4. Relate motion of objects to unbalanced and balanced forces in two dimensions. Key concepts: Changes in motion and common forces--speeding up, slowing down, turning, push, pull, friction, gravity, magnets. Constant motion and balanced forces. Additional forces--attraction, repulsion, action/ reaction pair (interaction force), buoyant force. Size of change is related to strength of unbalanced force and mass of object. Real- world contexts: Changing the direction--changing the direction of a billiard ball, bus turning a corner; changing the speed--car speeding up, a rolling ball slowing down, magnets changing the motion of objects, walking, swimming, jumping, rocket motion, objects resting on a table, tug- of- war. Future Unit 5. Design strategies for moving objects by application of forces, including the use of simple machines. Real- world contexts: Changing the direction--changing the direction of a billiard ball, bus turning a corner; changing the speed--car speeding up, a rolling ball slowing down, magnets changing the motion of objects, walking, swimming, jumping, rocket motion, objects resting on a table, tug- of- war. 1 11

10. Naïve ideas: 1. The distance an object travels and its displacement are always the same. 2. An object’s speed and velocity are always the same. 3. An object having inertia is always at rest. 4. Acceleration is always in a straight line. 5. Acceleration means that an object is speeding up. 6. The numerical value of acceleration is always a positive number. 6 0

11. Newton’s First Law An object stays at rest or continues to move in a straight line at a constant speed unless acted on by a force. V = d / t

12. t1 • t0 .50-meters Finish Point Starting Point Time Distance Observing Motion Trial 1 Sec. Trial 2 Sec. Trial 3 Sec. Average Sec. Distance meters Velocity Meters/sec 0.43 0.44 0.43 0.44 .500 1.14 0.31 0.32 0.32 0.32 .350 1.09 Equipment Set-Up 0 6

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16. Measuring The Velocity of Various Objects

17. 00 00 00 00 03 25 S T A R T S T O P Time • The interval between two events. 1

18. S T A R T S T O P Distance • The interval between two objects.

19. Measuring the Filling Speed of Water a. Turn the water on at a moderate rate. Keep this flow constant for both beakers. b. Fill the 400 ml. beaker with any amount (approximately one fourth of the beaker) of water, while timing (t). c. Mark the top of the water, and measure its distance in meters from the bottom of the beaker to the top of the water. d. Repeat this for two additional readings. e. Compute the distance (x) the water level rose using: x1 = L1 - L0 x2 = L2 - L1 x3 = L3 - L2 f. Compute the velocity of water flow using: v = x / t. g. Repeat this for two additional readings. h. Obtain average velocity of the water flow. i. Repeat for a 250 ml beaker. 3

20. ScienceScene.com Measuring The Speed Of A Clocks Second Hand a. Select a wall clock with a second hand. b. As the tip of the second hand rotates around the center of the clock traveling a certain distance (x), in a given time (t). d. Compute the distance traveled by the outer point of the second. e. Compute the speed using: v = x / t Note: • The tip of the second hand moves in a circle. In order to find the distance traveled, we must find the circumference of that circle. To determine the circumference, we must measure the radius (r) of the circle in meters. The radius is the distance between the center of the clock, and the tip of the second hand. Double that figure to obtain the diameter, and multiply that result by pi (3.14). • 2) The total distance traveled would be the number of full revolutions (N) multiplied by the distance traveled or x = (N) x 2r x 3.14. Call this distance x, and record.

21. Measuring The Velocity Of A Bouncing Ball. • The total distance (x) that the ball traveled is equal to the sum of the heights x1, x2 and x3. The initial height is x1, the final height is (x3) and the average of x1 and x3 is x2. The total distance (x) that the ball traveled is equal to the sum of the heights (x = x1 + x2 + x2 + x3). The heights are most easily measured by bouncing the ball near a wall, using the brick divisions to help in the measurement of the height of the bounce. • b. The time (t) taken for the ball to make two bounces would be measured from the starting point (the release point), to the end point (the top of the second bounce). • c. Compute the average speed using: v = x / t. • Collect three sets of data and calculate the average velocity. • e. Repeat for the second ball x2 x1 x2 x3 Total Distance (x) = x1 + x2 + x2 + x3 1 Simulation

22. Speed Of Sound BANG! Observers start their stopwatches when they see the flash of light created at the same instant a loud sound occurs. They stop their stopwatches when they hear the sound. Using their data calculate the speed of sound. Trial Distance Time Velocity 1 331.2-m 1.01-sec. 2 331.2-m 1.06-sec. 3 331.2-m 1.08-sec. 1. Experimental Speed of Sound = distance / time 2. Theoretical Speed of Sound = 330 m/sec. + (.6 m/sec. x Temperature) 3. Temperature = 23.1 ºC 4. Calculate Percent of Error 2

23. Inertia 2 Applying Large Force Applying Small Force

24. What is Inertia? Answer: The tendency of matter to remain at rest if it is at rest or, if moving, the tendency to keep moving in the same direction unless acted upon by some outside force. 2 1

25. Newton's First Law - Inertia 0

26. Inertia - Using Your Marbles

27. Newton’s First Law 2 4

28. Newton’s First Law 3

29. Newton’s First Law 2

30. Newton’s First Law 1 Click for Inertia Movie

31. Newton’s First Law 0

32. Newton’s Second Law When a force acts on a moving object, it will accelerate in the direction of the force dependent on its mass and the force. F = m x a

33. .500-meter .350-meter .150-meter t2 t0 t1 Starting Point B A Observing Acceleration - of a Toy Car 0.350-m t0→t1 0.500-m t0→t2 0.150-m t1→t2 (t2-t1) First time trial 0.32 0.43 0.11 Second time trial 0.31 0.44 0.13 Third time trial 0.32 0.43 0.11 (4) Average Time 0.32 0.44 0.12 (5) Average velocity v = d / t V1 1.09-m/s V2 1.25-m/s 6) Time (when average velocity occurred) Position A TA = t1/2 0.16-sec Position B TB = (t2 + t1) / 2 0.38-sec (6) v = change in adjacent velocity v= v2 – v1 0.16-m/s (7) T = change in time between adjacent velocity t = TB – TA 0.22-sec 13 (8) a = acceleration between points a = v / t .73-m/s/s .73-m/s2

34. Acceleration – A More Complete Picture Excel Worksheet – Push F9 to Reveal Calculations

35. Observing Forces Bubble Level Accelerometer Movement of the Car Direction of FORCE (movement of the accelerometer bubble) None It remains constant Forward It moves forward Backward It moves backward It moves towards the center of rotation Circular 1 8

36. Circular Motion The following diagram helps to explain the circular motion of an object. This motion depends on the object’s inertia,straight line direction, and theforce applied by a string pulling the object towards the center of the circle. ID ID ID = Inertia direction Rx = Resultant of Inertia & Center Pull ID R4 CP = Center Pull direction CP CP R3 CP ID CP CP ID R1 CP CP CP ID R2 ID 0 3 ID

37. ScienceScene Understanding Forces Types of Forces Pushes and Pulls 2

38. 2. 3. 1. 4. 7. 6. 5. Finding The Forces ActivitiesRead the description in the handout and identify the Forces for each activity 1 8

39. 5. At Rest 2. 3. 1. 1. At Rest 2. At Rest 4. 4. At Rest 3. Acceleration 7. 6. At Rest and Accelerating 7. Accelerating 6. 5. Finding The Forces Activities 0 7

40. Types of Forces A force is defined as any push or pull that results in accelerating motion Circular- When objects move in circles, a force acts with a direction that is toward the center of the circle. We call this direction CENTRIPETAL Gravitational- All objects attract all other objects with a force called gravitational force. Electromagnetic - Electric forces act on objects when the object carries a net electric charge or a non-uniform distribution of charge. Magnetic force is also observed around a moving electric charge and act on those charges. Physicists believe that all magnetic forces are produced by moving charges. Frictional- Frictional forces are often classified as sliding, rolling, static and fluid. Sliding and rolling frictional forces result when solids in contact pass by each other. Static frictional force results when solids are in contact, at rest and when a force or forces are trying to cause them to move with respect to each other. Fluid frictional force results when a solid is moving through a gas or a liquid. Normal - “Normal” means “perpendicular to”. Whenever an object is placed on a surface, a force acts normal to the surfaces in contact. This causes the supporting surface to sag. Since this sagging is slight, it often goes unnoticed. However, it is always there and the resulting force of the surface attempting to return to its original position is perpendicular to the surface. Tension-Tension force is the force exerted by a string, spring, beam or other object which is being stretched compressed. The electric forces among the molecules give rise to the force. Circular Gravitational Electromagnetic Frictional Normal Tension 7

41. Forces in a Collision • The diagram shows a child and an adult pushing on each other while holding bathroom scales to measure the forces. Predict how they will move. Explain your prediction. (Does the answer depend on who does the pushing? What if both push at the same time?) • Which scale will show the biggest number? • 3. Suppose the situation was slightly different than the illustration. For each situation below, predict how the readings on the scales would compare with each other. Explain your predictions. • a. If the adult’s chair was backed up against a wall. • b. If the child’s chair was backed up against a wall. • c. If both chairs were backed up against a wall.

42. The Falling Cup

43. The Affect of Mass on Acceleration Battery Trial 1 Sec. Trial 2 Sec. Trial 3 Sec. Average Sec. Distance meters Velocity Meters/sec Without 0.43 0.44 0.43 0.44 .500 1.14 0.56 0.57 0.60 0.58 .500 0.86 With 8

44. Newton’s Third Law Every Action Has An Equal And Opposite Reaction. f1 = f2 3

45. Newton’s Third Law 2

46. Newton’s Third Law 1

47. Newton’s Third Law 0

48. Equal and Opposite - Newton’s Third Law Slippery Plastic 1. Crumple the plastic until it looks very wrinkled 2. Place the slippery plastic on a solid, flat surface. 3. Place the car on top on the slippery plastic. 4. Start the car and observe the car and the slippery plastic. 4

49. Equal and Opposite, Another Look 1. Place two soda cans on a flat surface approximately 25-cm apart. 2. Place the plastic on top of the soda cans. 3. Place the car on top on the plastic as shown. 4. Start the car and carefully observe the car and the plastic. 3 2

50. The Hover CoverBalloon Powered Materials: Scissors, Plastic lid from a cottage cheese container, Push-pull squirt cap from a bottle of dishwashing liquid, Glue, Round balloon Instructions: 1. Cut a hole 3/4 inch in diameter in the center of the plastic lid from the cottage cheese container. 2. Center the push-pull squirt cap over the hole and glue it to the lid, with the lid's writing face up. Use enough glue so that no air spaces are left between the plastic surface of the cap and the plastic of the lid. Let the glue dry completely. 3. Blow up a round balloon and slip the opening over the opening on the closed squirt cap. 4. Place the device on a smooth sur­face, such as a table top, and lift the squirt-cap opening so that the air escapes from the balloon and your space car will glide effortlessly. 1