1. 1 Chapter 2 Objectives: 1)Define and distinguish “scalar” from “vector.” 2)Define and differentiate “speed” and “velocity.” 3)Be able to apply the relationship between velocity, distance, and time by solving velocity problems. 4)Define acceleration. 5)Know the relationship between acceleration and velocity and apply this relationship to solve acceleration problems. 6)Be able to create from data a “distance” versus “time” graph; a “velocity” versus “time” graph; and identify what the slopes of these graphs indicate about motion. 7)Define and differentiate “force” and “net force.” Provide examples of each.

2. 2 8)Show an understanding of both “contact forces” and “field forces” by providing examples of each. 9)Define inertia. 10)Know how an object in “free fall” is different than a falling object. What’s the acceleration due to gravity? 11)Define, with examples and non-examples, “projectile.” What is true regarding a projectile’s horizontal motion and vertical motion (how was this proved in class)? 12)Know the statements that are Newton’s Three Laws of Motion. Provide equations for both Newton’s 2 nd and 3 rd Laws. Be able to solve for force, mass, and/or acceleration using Newton’s motion equations. 13)Define and differentiate “momentum” and “impulse.”

3. 3 14)State the Law of Conservation of Momentum and provide an everyday example of this law. 15)Define and distinguish between “centripetal force” and “centrifugal force.” Which one is real? 16)State Newton’s Law of Gravitation, NlofG. Provide examples of this law both here on earth and in our universe. 17)Explain “weightlessness.”

4. 4 Chapter TWO: Motion I) Measuring Motion A) Speed and Velocity 1) Scalar or Vector a) _________: a quantity having only magnitude (size). b) _________: a quantity having both magnitude and direction.

5. 5 2) Speed: the rate of change in ___________ per change in ______. (scalar or vector) 3) Velocity: the speed of an object in a given direction. (scalar or vector) a) The Equation (Formula):

6. 6 b) The units: c) Sample Calculation 1: What is the average speed/velocity, in mph, of Mr. T’s car in the trip from Peoria to Metamora (16.2 miles) in a time of 27 minutes?

7. 7 d) Sample Calculation 2: How far away was a lightning strike if thunder is heard 5.00 seconds after seeing the flash of light (sound travels 340 m/s)?

8. 8 B) Acceleration 1) Acceleration: a change in velocity per change in time. 2) The Equation:

9. 9 3) The Units: 4) Sample Calculation: A sprinter moves from rest to 9.25 m/s in 10.2 seconds. What was the sprinter’s acceleration?

10. 10 C) Graphing Velocity and Acceleration 1) A distance versus time graph:

11. 11 a) Possible slopes:

12. 12 2) A velocity versus time graph:

13. 13 a) What’s happening?

14. 14 II) Forces A) Forces Defined 1) Force: a p_____ or p_____ that may cause a change in motion. a) The units:

15. 15 b) _____ Force: the sum of all the forces acting on an object.

16. 16 2) Types of forces: a) _________ Force: a force that exists due to the physical contact of two objects. b) _________ Force: a force that exists between two objects in the absence of physical contact. (a.k.a. Fundamental Forces)

17. 17 III) One and Two Dimensional Motion (and Forces) A) Horizontal Motion on Land 1) Aristotle and Galileo: a) Aristotle: objects desire motionlessness. b) Galileo: Objects want to move.

18. 18 2) ___________: a property of matter that resists changes in motion (stays at rest or stays moving). a) What is needed to overcome ___________? B) Falling Objects 1) Galileo: In the absence of air resistance, objects fall at the same rate! (coin and feather)

19. 19 2) _______ _____: an object falling only under the influence of gravity; no upward forces such as air resistance are acting. a) Objects in Free Fall accelerate at a constant rate due to gravity of ____ m/s 2.

20. 20 C) Compound Motion (a.k.a. Two Dimensional Motion or Projectile Motion) 1) ____________: any object thrown or shot into the air (not under its own power).

21. 21 a) A projectile’s horizontal motion and vertical motion are independent of each other! Prove it!

22. 22 IV) Newton’s Laws of Motion A) Newton’s 1 st Law: (the Law of ________) an object will remain in its present state of motion unless acted upon by a ____ _______. (table cloth pull and whiplash) B) Newton’s 2 nd Law: the acceleration of an object is directly proportional to the net force acting on it and indirectly proportional to its _______.

23. 23 1) The Equation:

24. 24 2) Sample Problem: A bicycle rider and bike have a combined mass of 95.4 kg. After applying the brakes the bicycle decelerates from 15 m/s to a stop in 3.0 seconds (acceleration is ______ m/s 2 ). What frictional force was applied by the brakes?

25. 25 3) Weight and Mass a) Mass: a measure of the amount of matter contained in an object. b) Weight: the force of gravity acting on an object.

26. 26 c) From Newton’s 2 nd Law:

27. 27 d) Sample Problem: What is the weight of a 190 lb (76 kg) person on the surface of the earth? How about on the surface of the moon where g = 1.63 m/s 2 ?

28. 28 C) Newton’s 3 rd Law: Whenever two objects interact, the force exerted by the first object onto the second object is equal to and opposite in direction to the force exerted by the second object onto the first (for every ________ force, there is an equal and opposite __________ force). Rockets and Balloons?

29. 29 V) Momentum A) Momentum and its Conservation 1) Momentum: the product of an object’s mass and velocity. a) The Equation: b) The Units:

30. 30 c) Sample Problem: Which has more momentum, a 9,090 kg semi truck parked on the side of the road or a 1.5 kg skateboard rolling down a hill at 3.73 m/s?

31. 31 2) Conservation of Momentum a) Conserved: b) The Law of Conservation of Momentum: The total momentum of a group of interacting objects remains the same in the absence of external forces. *Fan Cart and Collision Balls

32. 32 3) __________: the product of the magnitude of a force acting on an object and the amount of time the force is applied. Is equal to the change in momentum of an object. a) The Equations:

33. 33 b) Haystack or Brick Wall?

34. 34 VI) Forces and Circular Motion 1) ___________ _______: a force that pulls an object from its straight line path into a circular path. A) The Force a) Directed ___________.

35. 35 b) Centrifugal Force: a fictitious force that appears to push objects away from the center of a circular path. It is really ________.

36. 36 VII) Newton’s Law of Gravitation A)N.L. of G.: Every object in the universe is attracted to every other object with a force that is directly proportional to the product of their masses and indirectly proportional to the distance between them. It’s Newton’s ____ Law with gravity.

37. 37 1) The Equation:

38. 38 2) Sample Problem: What is the gravitational force between two 68 kg students sitting 1.0 m apart at their desks? What is the force of gravity between one of these students and the Earth?

39. 39 B) Weightlessness (Fact or Fiction) 1) You are really in _______ _____.