# Lecture Outline Chapter 5. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.

Save this PDF as:

Size: px
Start display at page:

Download "Lecture Outline Chapter 5. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc."

## Transcription

1 Lecture Outline Chapter 5 Physics, 4 th Edition James S. Walker

2 Chapter 5 Newton s Laws of Motion

3 Dynamics Force and Mass Units of Chapter 5 Newton s 1 st, 2 nd and 3 rd Laws of Motion The Vector Nature of Forces: Forces in Two Dimensions Weight Normal Forces

4 Newton s Concepts 1) m (mass): How much matter something contains 2) v (velocity): A body s speed and direction 3) a (acceleration): The change in a body s velocity per unit time 4) F (force): any external agent that causes a change in the motion of a free body

5 Force: push or pull 5-1 Force and Mass Force is a vector it has magnitude and direction

6 5-1 Force and Mass Mass is the measure of how hard it is to change an object s velocity. Mass can also be thought of as a measure of the quantity of matter in an object.

7 5-2 Newton s First Law of Motion If you stop pushing an object, does it stop moving? Only if there is friction! In the absence of any net external force, an object will keep moving at a constant speed in a straight line, or remain at rest. This is also known as the law of inertia.

8 5-2 Newton s First Law of Motion In order to change the velocity of an object magnitude or direction a net force is required. An inertial reference frame is one in which the first law is true. Accelerating reference frames are not inertial.

9 5-3 Newton s Second Law of Motion Observations show that the acceleration of an object is proportional to the net force exerted on it and inversely proportional to its mass: Or, more familiarly,

10 5-3 Newton s Second Law of Motion An object may have several forces acting on it; the acceleration is due to the net force: (5-1)

11 5-3 Newton s Second Law of Motion An object may have several forces acting on it; the acceleration is due to the net force: (5-1) In terms of vector components: F = ma F = ma F x x y y z = ma z

12 5-3 Newton s Second Law of Motion Free-body diagrams: A free-body diagram shows every force acting on an object. Sketch the forces Isolate the object of interest Choose a convenient coordinate system Resolve the forces into components Apply Newton s second law to each coordinate direction

13 5-3 Newton s Second Law of Motion Example of a free-body diagram:

14 5-3 Newton s Second Law of Motion Example 5-1: m boat = 753 kg, F = 80.5N. What are magnitudes and directions of accelerations in (a) and (b)

15 5-3 Newton s Second Law of Motion Example 5-1: m boat = 753 kg, F = 80.5N. What are magnitudes and directions of accelerations in (a) and (b) (a) Create free - body diagram, isolate source of interest and sketch the external forces on this body and their components. F x = ma x F L + F M + F C = ma x a x = 3(80.5N) 753kg = 0.321m/s2 (b) F x = ma x F L + F M F C = ma x a x = ( 80.5N) 753kg = 0.107m/s2

16 5-3 Newton s Second Law of Motion Example 5-2: m ball = 0.15 kg, v = 90 mi/h and Δx = 2m. Estimate the force on the ball.

17 5-3 Newton s Second Law of Motion Example 5-2: m ball = 0.15 kg, v = 90 mi/h and Δx = 2m. Estimate the force on the ball. Equation of motion along x - direction : v 2 = v a x Δx = 2aΔx a = v2 2Δx = Newton's Second Law : F x 90 mi h 2(2m) = ma x F x = (0.15kg)(400m/s 2 ) = 60N 2 = m 3600s 4m 2 = 400m/s 2

18 5-4 Newton s Third Law of Motion Forces always come in pairs, acting on different objects: If object 1 exerts a force on object 2, then object 2 exerts a force on object 1. These forces are called action-reaction pairs. NOTE: The action and reaction forces would appear in the free-body diagrams of different objects so they do not cancel out.

19 5-4 Newton s Third Law of Motion Some action-reaction pairs:

20 5-4 Newton s Third Law of Motion Example 5-3: m 1 = 150 kg, m 2 = 250 kg. The force of person in canoe 1 on canoe 2 is F = 46N. (a) acceleration of each canoe? (b) separation of canoes after t = 1.2s?

21 5-4 Newton s Third Law of Motion Example 5-3: m 1 = 150 kg, m 2 = 250 kg. The force of person in canoe 1 on canoe 2 is F = 46N. (a) acceleration of each canoe? (b) separation of canoes after t = 1.2s? Apply Newton's second law on each canoe : canoe 1: F 1x = m 1 a 1 canoe 2 : F 2x = m 2 a 2 Apply Newton's third Law : F 1 = (- 46 N)ˆ x F 2 = (46 N)ˆ x a 1 = F 1 m 1 = 46 N 150 kg = 0.31m/s2 a 2 = F 2 m 2 = Canoe 1 with the smallest mass accelerates more. 46N 250 kg = 0.18m/s2 x 1 = 1 2 a 1t 2 = 1 2 ( 0.31m/s2 )(1.2s) 2 = 0.22m x 2 = 1 2 a 2t 2 = 1 2 (0.18m/s2 )(1.2s) 2 = 0.13m Δx = x 2 - x 1 = 0.35m

22 5-4 Newton s Third Law of Motion Contact forces: The force exerted by one box on the other is different depending on which one you push.

23 5-4 Newton s Third Law of Motion Apply Newton's 2nd Law on both boxes : F = (m 1 +m 2 )a a = F (m 1 +m 2 ) case1: Force on small box 2. Box 2 exerts a force F 1 on box 1 and box 1 exerts an equal and opposite force F 2 on box 2. Contact force = F 1 = F 2 Apply Newton's 2nd law on box 1 (only one external force in x direction on box 1) : Contact Force : F 1 = m 1 a = m 1 F (m 1 +m 2 )

24 5-4 Newton s Third Law of Motion Apply Newton's 2nd Law on both boxes : F = (m 1 +m 2 )a a = F (m 1 +m 2 ) case2 : Force on large box 1. Box 2 exerts a force F 1 on box 1 and box 1 exerts an equal and opposite force F 2 on box 2. Contact force = F 1 = F 2 Apply Newton's 2nd law on box 2 (only one external force in x direction on box 2) : Contact Force : F 2 = m 2 a = m 2 F (m 1 +m 2 ) The contact force is larger when you push on the smaller box!

25 Newton s Laws of Motion 1) An object remains at rest, or moves in a straight line at a constant speed, unless acted upon by a net outside force. 2) A body s acceleration is proportional to the net outside force acting on the object, and will be in the direction of that force. Its resistance to acceleration depends on its mass. In equation form, this is F = m a m = mass of object (kg) a = acceleration of object (m/s 2 ) F = net external force (kg m/s 2 = Newton) 3) Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object.

26 5-5 The Vector Nature of Forces: Forces in Two Dimensions The easiest way to handle forces in two dimensions is to treat each dimension separately, as we did for kinematics.

27 5-5 Forces in Two Dimensions Example 5-5: Jack and Jill. m p = 1.30 kg F 1 = 7.0 N, F 2 = 11 N, W = 12.8 N and φ=28. (a) θ =? For a x = 0 (b) a y =?

28 5-5 Forces in Two Dimensions Example 5-5: Jack and Jill. m p = 1.30 kg F 1 = 7.0 N, F 2 = 11 N, W = 12.8 N and φ=28. (a) θ =? For a x = 0 (b) a y =? Use component form of Newton's seconds law : F x = ma x F y = ma y a x = 0 θ = 48 F x = 0 F 1 sinθ +F 2 sin28 = 0 sinθ = F 2 sin28 F 1 F y = F 1 cosθ +F 2 cos28 - W a y = F 1cosθ +F 2 cos28 - W m p a y = (7.0 N)cos48 +(11.0 N)cos N 1.30 kg =1.2m/s 2

29 5-6 Weight The weight of an object on the Earth s surface is the gravitational force exerted on it by the Earth.

30 5-6 Weight Example 5-6 : Where s the fire? m f = 97 kg, h = 3.0m, t = 1.2s. What is the upward force from the pole on the fireman?

31 5-6 Weight Example 5-6 : Where s the fire? m f = 97 kg, h = 3.0m, t = 1.2s. What is the upward force from the pole on the fireman? Apply Newtons' Second Law : F y = m f a y y = h a yt 2 a y = 2h t 2 F W = m f a y F - m f g = m f a y = 2(3.0m) = 4.2m/s 2 ( 1.2s) 2 Note that the total acceleration of the fireman is negative because it is pointed in the - y direction. F = m f (g + a y ) = 97 kg(9.81m/s 2 4.2m/s 2 ) = 540N

32 Apparent weight: 5-6 Weight Your perception of your weight is based on the contact forces between your body and your surroundings. If your surroundings are accelerating, your apparent weight may be more or less than your actual weight.

33 5-6 Weight Apparent weight : The force from the floor on person. Newton's Second Law on person : W a - W = ma y W a = m(g + a y ) Case 1: At rest a y = 0 and the apparent weight is equal to our weight Case 2 : For elevator accelerating upward a y > 0 and W a > W Case 3: For elevator accelerating downward a y < 0 and W a < W

34 5-6 Weight Example 5-7 : Don t buy Salmon in an upward accelerating elevator. What is the scale weight (a) at rest (b) upward acceleration of 2.5m/s 2 (c) downward acceleration of 3.2m/s 2.

35 5-6 Weight Example 5-7 : Don t buy Salmon in an upward accelerating elevator F y = ma y F y = W a W = W a mg W a = m(g + a y )ˆ y (a) At rest a y = 0 and W a = mgˆ y = 5.0kg(9.81m/s 2 )ˆ y = 49Nˆ y (b) W a = 5.0kg(9.81m/s m/s 2 )ˆ y = 62Nˆ y (your're paying too much) (c) W a = 5.0kg(9.81m/s 2-3.2m/s 2 )ˆ y = 33Nˆ y

36 W a = m(g + a) For a = - g one has zero apparent weight

37 5-7 Normal Forces The normal force is the force exerted by a surface on an object.

38 5-7 Normal Forces The normal force may be equal to, greater than, or less than the weight.

39 5-7 Normal Forces Example 5-8: Ice Block F1 = 13 N, F2 = 11 N (a) What is the acceleration of the ice? (b) What is the normal force on the ice?

40 5-7 Normal Forces Example 5-8: Ice Block F 1 = 13 N, F 2 = 11 N, m = 6.0 kg (a) What is the acceleration of the ice? (b) What is the normal force on the ice? F x = ma x F y = ma y F x = F 1x +F 2x = F 1 cos60 F 2 cos30 = (13N)0.5 - (11N)0.87 = 6.5N - 9.5N = -3N (a) ma x = - 3 N a x = -3 N 6.0kg = 0.5m/s2 a = m/s 2ˆ x F y = 0 F N W F 1y F 2y = 0 F N mg F 1 sin60 F 2 sin30 = 0 F N = mg + F 1 sin60 + F 2 sin30 = (6.0kg)(9.81m/s 2 ) +(13 N)(0.87) +(11 N)(0.5) F N = 75N F N = 75N y ˆ

41 5-7 Normal Forces The normal force is always perpendicular to the surface.

42 5-7 Normal Forces Example 5-9: Toboggan, m and θ known (a) What is the acceleration of the child? (b) What is the normal force on the child?

43 5-7 Normal Forces Example 5-9: Toboggan, m and θ known (a) What is the acceleration of the child? (b) What is the normal force on the child? F x = ma x F y = ma y F x = W x = ma x a x = W x m = mgsinθ m = gsinθ F y = F N Wcosθ = ma y = 0 F N = mgcosθ F N = mgcosθˆ y

44 Summary of Chapter 5 Force: a push or pull Mass: measures the difficulty in accelerating an object Newton s first law: if the net force on an object is zero, its velocity is constant Inertial frame of reference: one in which the first law holds Newton s second law: Free-body diagram: a sketch showing all the forces on an object

45 Summary of Chapter 5 Newton s third law: If object 1 exerts a force on object 2, then object 2 exerts a force on object 1. Contact forces: an action-reaction pair of forces produced by two objects in physical contact Forces are vectors Newton s laws can be applied to each component of the forces independently Weight: gravitational force exerted by the Earth on an object

46 Summary of Chapter 5 On the surface of the Earth, W = mg Apparent weight: force felt from contact with a floor or scale Normal force: force exerted perpendicular to a surface by that surface Normal force may be equal to, lesser than, or greater than the object s weight

### Chapter 5 Newton s Laws of Motion

Chapter 5 Newton s Laws of Motion Force and Mass Units of Chapter 5 Newton s First Law of Motion Newton s Second Law of Motion Newton s Third Law of Motion The Vector Nature of Forces: Forces in Two Dimensions

### Newton s Laws of Motion

Physics Newton s Laws of Motion Newton s Laws of Motion 4.1 Objectives Explain Newton s first law of motion. Explain Newton s second law of motion. Explain Newton s third law of motion. Solve problems

### Chapter 4. Forces and Newton s Laws of Motion. continued

Chapter 4 Forces and Newton s Laws of Motion continued 4.9 Static and Kinetic Frictional Forces When an object is in contact with a surface forces can act on the objects. The component of this force acting

### Chapter 4 Newton s Laws: Explaining Motion

Chapter 4 Newton s s Laws: Explaining Motion Newton s Laws of Motion The concepts of force, mass, and weight play critical roles. A Brief History! Where do our ideas and theories about motion come from?!

### Newton s Laws of Motion

Chapter 4 Newton s Laws of Motion PowerPoint Lectures for University Physics, Thirteenth Edition Hugh D. Young and Roger A. Freedman Lectures by Wayne Anderson Goals for Chapter 4 To understand the meaning

### Chapter 4: Newton s Laws of Motion

Chapter 4: Newton s Laws of Motion Dynamics: Study of motion and its causes. orces cause changes in the motion of an object. orce and Interactions Definition ( loose ): A force is a push or pull exerted

### Objective: Equilibrium Applications of Newton s Laws of Motion I

Type: Single Date: Objective: Equilibrium Applications of Newton s Laws of Motion I Homework: Assignment (1-11) Read (4.1-4.5, 4.8, 4.11); Do PROB # s (46, 47, 52, 58) Ch. 4 AP Physics B Mr. Mirro Equilibrium,

### Chapter 4 Dynamics: Newton s Laws of Motion. Copyright 2009 Pearson Education, Inc.

Chapter 4 Dynamics: Newton s Laws of Motion Force Units of Chapter 4 Newton s First Law of Motion Mass Newton s Second Law of Motion Newton s Third Law of Motion Weight the Force of Gravity; and the Normal

### Ground Rules. PC1221 Fundamentals of Physics I. Force. Zero Net Force. Lectures 9 and 10 The Laws of Motion. Dr Tay Seng Chuan

PC1221 Fundamentals of Physics I Lectures 9 and 10 he Laws of Motion Dr ay Seng Chuan 1 Ground Rules Switch off your handphone and pager Switch off your laptop computer and keep it No talking while lecture

### Newton s Laws of Motion

Section 3.2 Newton s Laws of Motion Objectives Analyze relationships between forces and motion Calculate the effects of forces on objects Identify force pairs between objects New Vocabulary Newton s first

### Chapter 4. Forces and Newton s Laws of Motion. continued

Chapter 4 Forces and Newton s Laws of Motion continued Clicker Question 4.3 A mass at rest on a ramp. How does the friction between the mass and the table know how much force will EXACTLY balance the gravity

### General Physics (PHY 2130)

General Physics (PHY 2130) Lecture 8 Forces Newton s Laws of Motion http://www.physics.wayne.edu/~apetrov/phy2130/ Classical Mechanics Describes the relationship between the motion of objects in our everyday

### Newton s Laws of Motion

Chapter 4 Newton s Laws of Motion PowerPoint Lectures for University Physics, Twelfth Edition Hugh D. Young and Roger A. Freedman Lectures by James Pazun Modified by P. Lam 7_8_2016 Goals for Chapter 4

### Forces. Lecturer: Professor Stephen T. Thornton

Forces Lecturer: Professor Stephen T. Thornton Reading Quiz: Which of Newton s laws refers to an action and a reaction acceleration? A) First law. B) Second law. C) Third law. D) This is a trick question.

### 04-1. Newton s First Law Newton s first law states: Sections Covered in the Text: Chapters 4 and 8 F = ( F 1 ) 2 + ( F 2 ) 2.

Force and Motion Sections Covered in the Text: Chapters 4 and 8 Thus far we have studied some attributes of motion. But the cause of the motion, namely force, we have essentially ignored. It is true that

### Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion. Physics is about forces and how the world around us reacts to these forces.

Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion Physics is about forces and how the world around us reacts to these forces. Whats a force? Contact and non-contact forces. Whats a

### PHYSICS 149: Lecture 4

PHYSICS 149: Lecture 4 Chapter 2 2.3 Inertia and Equilibrium: Newton s First Law of Motion 2.4 Vector Addition Using Components 2.5 Newton s Third Law 1 Net Force The net force is the vector sum of all

### 5. Forces and Motion-I. Force is an interaction that causes the acceleration of a body. A vector quantity.

5. Forces and Motion-I 1 Force is an interaction that causes the acceleration of a body. A vector quantity. Newton's First Law: Consider a body on which no net force acts. If the body is at rest, it will

### Chapter 4. Forces and Newton s Laws of Motion

Chapter 4 Forces and Newton s Laws of Motion 4.1 The Concepts of Force and Mass A force is a push or a pull. Contact forces arise from physical contact. Action-at-a-distance forces do not require contact

Section Review Answers Chapter 12 Section 1 1. Answers may vary. Students should say in their own words that an object at rest remains at rest and an object in motion maintains its velocity unless it experiences

### Force. A force is a push or a pull. Pushing on a stalled car is an example. The force of friction between your feet and the ground is yet another.

Force A force is a push or a pull. Pushing on a stalled car is an example. The force of friction between your feet and the ground is yet another. Force Weight is the force of the earth's gravity exerted

### Lecture 9. Friction in a viscous medium Drag Force Quantified

Lecture 9 Goals Describe Friction in Air (Ch. 6) Differentiate between Newton s 1 st, 2 nd and 3 rd Laws Use Newton s 3 rd Law in problem solving Assignment: HW4, (Chap. 6 & 7, due 10/5) 1 st Exam Thurs.,

### Newton s Third Law. object 1 on object 2 is equal in magnitude and opposite in direction to the force exerted by object 2 on object 1

Newton s Third Law! If two objects interact, the force exerted by object 1 on object 2 is equal in magnitude and opposite in direction to the force exerted by object 2 on object 1!! Note on notation: is

### Newton s Laws. Physics 1425 lecture 6. Michael Fowler, UVa.

Newton s Laws Physics 1425 lecture 6 Michael Fowler, UVa. Newton Extended Galileo s Picture of Galileo said: Motion to Include Forces Natural horizontal motion is at constant velocity unless a force acts:

### Newton's laws of motion

Newton's laws of motion Forces Forces as vectors Resolving vectors Explaining motion - Aristotle vs Newton Newton s first law Newton s second law Weight Calculating acceleration Newton s third law Moving

### v v ax v a x a v a v = = = Since F = ma, it follows that a = F/m. The mass of the arrow is unchanged, and ( )

Week 3 homework IMPORTANT NOTE ABOUT WEBASSIGN: In the WebAssign versions of these problems, various details have been changed, so that the answers will come out differently. The method to find the solution

### Physics 101 Prof. Ekey. Chapter 5 Force and motion (Newton, vectors and causing commotion)

Physics 101 Prof. Ekey Chapter 5 Force and motion (Newton, vectors and causing commotion) Goal of chapter 5 is to establish a connection between force and motion This should feel like chapter 1 Questions

### Chapter 4. Dynamics: Newton s Laws of Motion

Chapter 4 Dynamics: Newton s Laws of Motion The Concepts of Force and Mass A force is a push or a pull. Contact forces arise from physical contact. Action-at-a-distance forces do not require contact and

### Dynamics- Why do objects move as they do? What makes an object at rest, begin to move? What makes a body accelerate or decelerate?

Dynamics- Why do objects move as they do? What makes an object at rest, begin to move? What makes a body accelerate or decelerate? What makes an object move in a circle? Force A Force is simply a push

### Physics Notes Class 11 CHAPTER 5 LAWS OF MOTION

1 P a g e Inertia Physics Notes Class 11 CHAPTER 5 LAWS OF MOTION The property of an object by virtue of which it cannot change its state of rest or of uniform motion along a straight line its own, is

### Recap. A force is the product of an object s mass and acceleration. Forces are the reason why objects change their velocity. Newton s second law:

Recap A force is the product of an object s mass and acceleration. Forces are the reason why objects change their velocity. Newton s second law: Unit: 1 N = 1 kg m/s 2 Forces are vector quantities, since

### Explaining Motion:Forces

Explaining Motion:Forces Chapter Overview (Fall 2002) A. Newton s Laws of Motion B. Free Body Diagrams C. Analyzing the Forces and Resulting Motion D. Fundamental Forces E. Macroscopic Forces F. Application

### Physics 11 Assignment KEY Dynamics Chapters 4 & 5

Physics Assignment KEY Dynamics Chapters 4 & 5 ote: for all dynamics problem-solving questions, draw appropriate free body diagrams and use the aforementioned problem-solving method.. Define the following

### Newton s Laws are empirical laws, deduced from experiment; they cannot be derived from anything more fundamental!

NEWTON S LAWS O OTION Newton s Laws are the foundation of Classical (Newtonian) echanics. They were published by Isaac Newton in 1687 along with the law of gravitation in the Principia. They have far reaching

### Mass, energy, power and time are scalar quantities which do not have direction.

Dynamics Worksheet Answers (a) Answers: A vector quantity has direction while a scalar quantity does not have direction. Answers: (D) Velocity, weight and friction are vector quantities. Note: weight and

### Lecture 6. Weight. Tension. Normal Force. Static Friction. Cutnell+Johnson: 4.8-4.12, second half of section 4.7

Lecture 6 Weight Tension Normal Force Static Friction Cutnell+Johnson: 4.8-4.12, second half of section 4.7 In this lecture, I m going to discuss four different kinds of forces: weight, tension, the normal

### Describe the relationship between gravitational force and distance as shown in the diagram.

Name Period Chapter 2 The Laws of Motion Review Describe the relationship between gravitational force and distance as shown in the diagram. Assess the information about gravity, mass, and weight. Read

### What is a force? Identifying forces. What is the connection between force and motion? How are forces related when two objects interact?

Chapter 4: Forces What is a force? Identifying forces. What is the connection between force and motion? How are forces related when two objects interact? Application different forces (field forces, contact

### TEACHER ANSWER KEY November 12, 2003. Phys - Vectors 11-13-2003

Phys - Vectors 11-13-2003 TEACHER ANSWER KEY November 12, 2003 5 1. A 1.5-kilogram lab cart is accelerated uniformly from rest to a speed of 2.0 meters per second in 0.50 second. What is the magnitude

### For every action, there is an and.

SPH4C1 Lesson 03 Newton s Laws NEWTON S THIRD LAW LEARNING GOALS Students will: Be able to state Newton s 3 rd Law and apply it in qualitative and quantitative terms to explain the effect of forces acting

### 2.1 Force and Motion Kinematics looks at velocity and acceleration without reference to the cause of the acceleration.

2.1 Force and Motion Kinematics looks at velocity and acceleration without reference to the cause of the acceleration. Dynamics looks at the cause of acceleration: an unbalanced force. Isaac Newton was

### Chapter 4 Dynamics: Newton s Laws of Motion

Chapter 4 Dynamics: Newton s Laws of Motion Units of Chapter 4 Force Newton s First Law of Motion Mass Newton s Second Law of Motion Newton s Third Law of Motion Weight the Force of Gravity; and the Normal

### physics 111N forces & Newton s laws of motion

physics 111N forces & Newton s laws of motion forces (examples) a push is a force a pull is a force gravity exerts a force between all massive objects (without contact) (the force of attraction from the

### Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion

Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion Conceptual Questions 1) Which of Newton's laws best explains why motorists should buckle-up? A) the first law

### Chapter 18 Static Equilibrium

Chapter 8 Static Equilibrium 8. Introduction Static Equilibrium... 8. Lever Law... Example 8. Lever Law... 4 8.3 Generalized Lever Law... 5 8.4 Worked Examples... 7 Example 8. Suspended Rod... 7 Example

### Introduction to Newton's Laws of Motion 1642-1726

Introduction to Newton's Laws of Motion 1642-1726 Outlook 1.The First Law on inertia states that every object will remain in a state of rest or uniform motion in a straight line unless acted upon by an

### Physics 101. Chapter 5: Newton s Third Law

Physics 101 Today Chapter 5: Newton s Third Law First, let s clarify notion of a force: Previously defined force as a push or pull. Better to think of force as an interaction between two objects. You can

### NEWTON S LAWS OF MOTION

NEWTON S LAWS OF MOTION Background: Aristotle believed that the natural state of motion for objects on the earth was one of rest. In other words, objects needed a force to be kept in motion. Galileo studied

### Newton s Law of Motion

chapter 5 Newton s Law of Motion Static system 1. Hanging two identical masses Context in the textbook: Section 5.3, combination of forces, Example 4. Vertical motion without friction 2. Elevator: Decelerating

### Physics I Honors: Chapter 4 Practice Exam

Physics I Honors: Chapter 4 Practice Exam Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Which of the following statements does not describe

### Described by Isaac Newton

Described by Isaac Newton States observed relationships between motion and forces 3 statements cover aspects of motion for single objects and for objects interacting with another object An object at rest

### Chapter 5 Newton s Laws of Motion

Chapter 5 Newton s Laws of Motion Sir Isaac Newton (1642 1727) Developed a picture of the universe as a subtle, elaborate clockwork slowly unwinding according to well-defined rules. The book Philosophiae

### Friction and Newton s 3rd law

Lecture 4 Friction and Newton s 3rd law Pre-reading: KJF 4.8 Frictional Forces Friction is a force exerted by a surface. The frictional force is always parallel to the surface Due to roughness of both

### Conceptual Physics 11 th Edition. Forces and Interactions. Newton s Third Law of Motion. This lecture will help you understand:

This lecture will help you understand: Conceptual Physics 11 th Edition Chapter 5: NEWTON S THIRD LAW OF MOTION Forces and Interactions Summary of Newton s Laws Vectors Forces and Interactions Interaction

### Conceptual Physics 11 th Edition

Conceptual Physics 11 th Edition Chapter 5: NEWTON S THIRD LAW OF MOTION This lecture will help you understand: Forces and Interactions Newton s Third Law of Motion Summary of Newton s Laws Vectors Forces

### STATICS. Introduction VECTOR MECHANICS FOR ENGINEERS: Eighth Edition CHAPTER. Ferdinand P. Beer E. Russell Johnston, Jr.

Eighth E CHAPTER VECTOR MECHANICS FOR ENGINEERS: STATICS Ferdinand P. Beer E. Russell Johnston, Jr. Introduction Lecture Notes: J. Walt Oler Texas Tech University Contents What is Mechanics? Fundamental

### W02D2-2 Table Problem Newton s Laws of Motion: Solution

ASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics Physics 8.01 W0D- Table Problem Newton s Laws of otion: Solution Consider two blocks that are resting one on top of the other. The lower block

### Chapter 4A. Translational Equilibrium. A PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University

Chapter 4. Translational Equilibrium PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University 2007 MOUNTIN CLIMER exerts action forces on crevices and ledges,

### UNIT 2D. Laws of Motion

Name: Regents Physics Date: Mr. Morgante UNIT 2D Laws of Motion Laws of Motion Science of Describing Motion is Kinematics. Dynamics- the study of forces that act on bodies in motion. First Law of Motion

### 1206EL - Concepts in Physics. Friday, September 18th

1206EL - Concepts in Physics Friday, September 18th Notes There is a WebCT course for students on September 21st More information on library webpage Newton s second law Newton's first law of motion predicts

### Chapter 3: Force and Motion

Force and Motion Cause and Effect Chapter 3 Chapter 3: Force and Motion Homework: All questions on the Multiple- Choice and the odd-numbered questions on Exercises sections at the end of the chapter. In

### Chapter 6. Work and Energy

Chapter 6 Work and Energy The concept of forces acting on a mass (one object) is intimately related to the concept of ENERGY production or storage. A mass accelerated to a non-zero speed carries energy

### Newton s Third Law. Newton s Third Law of Motion. Action-Reaction Pairs

Section 4 Newton s Third Law Reading Preview Key Concepts What is Newton s third law of motion? How can you determine the momentum of an object? What is the law of conservation of momentum? Key Terms momentum

### Example (1): Motion of a block on a frictionless incline plane

Firm knowledge of vector analysis and kinematics is essential to describe the dynamics of physical systems chosen for analysis through ewton s second law. Following problem solving strategy will allow

### Newton s Laws Pre-Test

Newton s Laws Pre-Test 1.) Consider the following two statements and then select the option below that is correct. (i) It is possible for an object move in the absence of forces acting on the object. (ii)

### Forces: Equilibrium Examples

Physics 101: Lecture 02 Forces: Equilibrium Examples oday s lecture will cover extbook Sections 2.1-2.7 Phys 101 URL: http://courses.physics.illinois.edu/phys101/ Read the course web page! Physics 101:

### Newton s Laws of Motion

Newton s Laws of Motion Newton s Laws and the Mousetrap Racecar Simple version of Newton s three laws of motion 1 st Law: objects at rest stay at rest, objects in motion stay in motion 2 nd Law: force

### 2.2 NEWTON S LAWS OF MOTION

2.2 NEWTON S LAWS OF MOTION Sir Isaac Newton (1642-1727) made a systematic study of motion and extended the ideas of Galileo (1564-1642). He summed up Galileo s observation in his three laws of motion

### Lecture 7 Force and Motion. Practice with Free-body Diagrams and Newton s Laws

Lecture 7 Force and Motion Practice with Free-body Diagrams and Newton s Laws oday we ll just work through as many examples as we can utilizing Newton s Laws and free-body diagrams. Example 1: An eleator

### Gravitational Potential Energy

Gravitational Potential Energy Consider a ball falling from a height of y 0 =h to the floor at height y=0. A net force of gravity has been acting on the ball as it drops. So the total work done on the

### SOLID MECHANICS DYNAMICS TUTORIAL INERTIA FORCES IN MECHANISMS

SOLID MECHANICS DYNAMICS TUTORIAL INERTIA FORCES IN MECHANISMS This work covers elements of the syllabus for the Engineering Council Exam D225 Dynamics of Mechanical Systems C103 Engineering Science. This

### CHAPTER 6 WORK AND ENERGY

CHAPTER 6 WORK AND ENERGY CONCEPTUAL QUESTIONS. REASONING AND SOLUTION The work done by F in moving the box through a displacement s is W = ( F cos 0 ) s= Fs. The work done by F is W = ( F cos θ). s From

### Forces. Definition Friction Falling Objects Projectiles Newton s Laws of Motion Momentum Universal Forces Fluid Pressure Hydraulics Buoyancy

Forces Definition Friction Falling Objects Projectiles Newton s Laws of Motion Momentum Universal Forces Fluid Pressure Hydraulics Buoyancy Definition of Force Force = a push or pull that causes a change

### VELOCITY, ACCELERATION, FORCE

VELOCITY, ACCELERATION, FORCE velocity Velocity v is a vector, with units of meters per second ( m s ). Velocity indicates the rate of change of the object s position ( r ); i.e., velocity tells you how

### Chapter 12 - Forces and Motion

Chapter 12 - Forces and Motion A. What is a force? 1. It is a push or pull. 2. Force can cause resting objects to move. 3. Force can cause acceleration by changing the object s speed or direction. 4. Newtons

### QUESTIONS : CHAPTER-5: LAWS OF MOTION

QUESTIONS : CHAPTER-5: LAWS OF MOTION 1. What is Aristotle s fallacy? 2. State Aristotlean law of motion 3. Why uniformly moving body comes to rest? 4. What is uniform motion? 5. Who discovered Aristotlean

### Weight The weight of an object is defined as the gravitational force acting on the object. Unit: Newton (N)

Gravitational Field A gravitational field as a region in which an object experiences a force due to gravitational attraction Gravitational Field Strength The gravitational field strength at a point in

### A Review of Vector Addition

Motion and Forces in Two Dimensions Sec. 7.1 Forces in Two Dimensions 1. A Review of Vector Addition. Forces on an Inclined Plane 3. How to find an Equilibrant Vector 4. Projectile Motion Objectives Determine

### COURSE CONTENT. Introduction. Definition of a Force Effect of Forces Measurement of forces. Newton s Laws of Motion

CHAPTER 13 - FORCES COURSE CONTENT Introduction Newton s Laws of Motion Definition of a Force Effect of Forces Measurement of forces Examples of Forces A force is just a push or pull. Examples: an object

### AP Physics Applying Forces

AP Physics Applying Forces This section of your text will be very tedious, very tedious indeed. (The Physics Kahuna is just as sorry as he can be.) It s mostly just a bunch of complicated problems and

### MOTION AND FORCE: DYNAMICS

MOTION AND FORCE: DYNAMICS We ve been dealing with the fact that objects move. Velocity, acceleration, projectile motion, etc. WHY do they move? Forces act upon them, that s why! The connection between

### Physics 11 Chapter 4 HW Solutions

Physics 11 Chapter 4 HW Solutions Chapter 4 Conceptual Question: 5, 8, 10, 18 Problems: 3, 3, 35, 48, 50, 54, 61, 65, 66, 68 Q4.5. Reason: No. If you know all of the forces than you know the direction

### PS-5.1 Explain the relationship among distance, time, direction, and the velocity of an object.

PS-5.1 Explain the relationship among distance, time, direction, and the velocity of an object. It is essential for students to Understand Distance and Displacement: Distance is a measure of how far an

### F13--HPhys--Q5 Practice

Name: Class: Date: ID: A F13--HPhys--Q5 Practice Multiple Choice Identify the choice that best completes the statement or answers the question. 1. A vector is a quantity that has a. time and direction.

### Unification of the laws of the Earth and the Universe Why do planets appear to wander slowly across the sky?

October 19, 2015 Unification of the laws of the Earth and the Universe Why do planets appear to wander slowly across the sky? Key Words Newton s Laws of motion, and Newton s law of universal gravitation:

### D) A block pulled with a constant force will have a constant acceleration in the same direction as the force.

Phsics 100A Homework 4 Chapter 5 Newton s First Law A)If a car is moving to the left with constant velocit then the net force applied to the car is zero. B) An object cannot remain at rest unless the net

### Newton s Laws of Motion. I. Law of Inertia II. F=ma III. Action-Reaction

Newton s Laws of Motion I. Law of Inertia II. F=ma III. Action-Reaction While most people know what Newton's laws say, many people do not know what they mean (or simply do not believe what they mean).

### Unsaved Test, Version: 1 1

Name: Select the term that best completes the statement. A. force B. net force C. unbalanced force D. Newton's first law E. motion F. inertia 1. is the change of position over time. Date: 2. The overall

### More of Newton s Laws

More of Newton s Laws Announcements: Tutorial Assignments due tomorrow. Pages 19-21, 23, 24 (not 22,25) Note Long Answer HW due this week. CAPA due on Friday. Have added together the clicker scores so

### C B A T 3 T 2 T 1. 1. What is the magnitude of the force T 1? A) 37.5 N B) 75.0 N C) 113 N D) 157 N E) 192 N

Three boxes are connected by massless strings and are resting on a frictionless table. Each box has a mass of 15 kg, and the tension T 1 in the right string is accelerating the boxes to the right at a

### Vectors and the Inclined Plane

Vectors and the Inclined Plane Introduction: This experiment is designed to familiarize you with the concept of force as a vector quantity. The inclined plane will be used to demonstrate how one force

### Newton's First Law. Newton s Laws. Page 1 of 6

Newton's First Law Newton s Laws In previous units, the variety of ways by which motion can be described (words, graphs, diagrams, numbers, etc.) was discussed. In this unit (Newton's Laws of Motion),

### F = ma. F = mg. Forces. Forces. Free Body Diagrams. Find the unknown forces!! Ex. 1 Ex N. Newton s First Law. Newton s Second Law

Forces Free Body Diagrams Push or pull on an object Causes acceleration Measured in Newtons N = Kg m s Shows all forces as vectors acting on an object Vectors always point away from object Used to help

### Newton s Laws of Motion. Presented by: - Rakhi Gupta(166) Tamanpreet Kaur(211)

Newton s Laws of Motion Presented by: - Rakhi Gupta(166) Tamanpreet Kaur(211) Contents of the Presentation Newton s First law of Motion Balance and Unbalanced Force Newton s Second law of Motion Free Falling

### Motion Lesson 1: Review of Basic Motion

Motion in one and two dimensions: Lesson 1 Semi-notes Motion Lesson 1: Review of Basic Motion Note. For these semi notes we will use the bold italics convention to represent vectors. Complete the following

### Review Vocabulary force: a push or a pull. Vocabulary Newton s third law of motion

Standard 7.3.17: Investigate that an unbalanced force, acting on an object, changes its speed or path of motion or both, and know that if the force always acts toward the same center as the object moves,

### Lecture 07: Work and Kinetic Energy. Physics 2210 Fall Semester 2014

Lecture 07: Work and Kinetic Energy Physics 2210 Fall Semester 2014 Announcements Schedule next few weeks: 9/08 Unit 3 9/10 Unit 4 9/15 Unit 5 (guest lecturer) 9/17 Unit 6 (guest lecturer) 9/22 Unit 7,

### At the skate park on the ramp

At the skate park on the ramp 1 On the ramp When a cart rolls down a ramp, it begins at rest, but starts moving downward upon release covers more distance each second When a cart rolls up a ramp, it rises