General Physics I Spring Applying Newton s Laws
|
|
- Melvyn Smith
- 5 years ago
- Views:
Transcription
1 General Physics I Spring 2011 pplying Newton s Laws 1
2 Friction When you push horizontally on a heavy box at rest on a horizontal floor with a steadily increasing force, the box will remain at rest initially, i.e., remain in equilibrium. Since the box is in equilibrium, the net force in the horizontal direction is zero, i.e., there must be a force opposing your push. This force is the force of static friction. Static friction is friction that acts when surfaces in contact are at rest relative to each other. 2
3 Static Friction s you continue to increase the applied force, the magnitude of the static friction (f s ) rises to match the magnitude of the applied force and the box remains at rest. Eventually, the box will begin to move relative to the floor when the applied force exceeds the magnitude of the maximum static friction force (f s,max ) for the two surfaces. Experimentally, it has been found that f s,max is approximately proportional to the magnitude of the normal force acting on each surface: f s,max = µ s n, where µ s is the coefficient of static friction for the two surfaces. 3
4 Kinetic Friction When there is relative motion between the surfaces, the friction force becomes kinetic friction (f k ). Kinetic friction is in the opposite direction to the motion of one surface relative to the other. It has also been found experimentally that the magnitude of the kinetic friction force is approximately proportional to the magnitude of the normal force: f k = µ k n, where µ k is the coefficient of kinetic friction. For the same two surfaces, usually µ k < µ s. Note that both surfaces experience the friction force, according to Newton s third law. 4
5 Kinetic Friction Kinetic friction is independent of speed and area of contact. 5
6 Static and Kinetic Friction Graph of friction force vs. time as the box is pushed. 6
7 Friction and Driving Under normal circumstances, the force that propels your car forward is static friction between the tires are the road. The bottom surface of a tire does not slip relative to the road. Note that friction is in the same direction as the motion of the car. That is why it is important to note that friction opposes relative motion between surfaces. (The tire pushes back on the road; friction opposes this attempted backward relative motion and so acts in the forward direction.) When you are braking, it is also better that static friction slows you down. If the brakes lock, the tires slip and the friction will be kinetic friction, which is usually less than the maximum static friction force. nti-lock brakes prevent this from happening. When the roads are icy, the coefficients of static and kinetic friction are much smaller. The tires slip much more easily and the friction forces are much reduced, making driving more difficult. 7
8 Workbook: Chapter 5, Question 21 8
9 Interacting Objects s we saw before, when objects interact, they experience forces that come in action/reaction pairs due to Newton s third law. Each force that constitutes a pair acts on a different object. These forces have to be treated carefully when solving problems involving interacting objects. Note that the forces of a pair have the same magnitude and this is a useful piece of information in solving problems involving interacting objects. The figure and freebody diagrams illustrate these ideas. F on F = F on w on n F hand n w F on 9
10 Interacting Objects: ccelerations In many cases, the accelerations of two interacting bodies will be related. For example, for two blocks being pushed while they are in contact, their accelerations are equal. Otherwise, the blocks would separate. pplying Newton s 2 nd law to each block yields: lock F = F F = m a (1) lock Fx = F = m a (2) on Since F = F, we can substitute for on on F in Eq. (1) to get F m a= m a or, F on hand x hand on = m m + a. hand F on w n F hand n w F on x x 10
11 Interacting Objects: ccelerations For two objects connected by a rope or string that doesn t stretch or shrink, the magnitudes of the accelerations are the same. In the example to the right, though the directions of the accelerations are different, their magnitudes are the same. Thus, a = a. In terms of components, a = a. x y (Note that the acceleration of is in the negative y direction and so a is actually negative.) y 11
12 In this course, we will assume that ropes or strings are massless and pulleys are massless and frictionless. The tension in a massless rope is the same everywhere in the rope, including at both ends (which are connected to other objects). The rope exerts a force on a connected object equal to the tension. (The object of course exerts a reaction force on the rope having the same magnitude as the tension.) Ropes and Pulleys 12
13 When a rope or string passes over a pulley, the magnitude of the tension in the rope is the same on both sides of the pulley. y n T Ropes and Pulleys x Frictionless surface y T w T = T w 13
14 Workbook: Chapter 5, Question 26, 29 14
15 Textbook: Chapter 5, Problem 74 y T T m = 100 kg w w First, we have to find the acceleration of the 100-kg block. Use: y = y ( ) 1 2 i + vy i t+ 2 a ( t). f y Knowns: y = 1 m, y = 0 m, t = 6.0 s, ( v ) = 0. Unknown: a. f Solving for a gives: a y i y i y y 2 y yi ( vy) f i t = = 2( 1 m 0 0) = m/s 2. ( t) 2 (6.0 s) 2 15
16 Problem 74 (continued) pply Newton's 2nd law to the 100-kg block. F = T w = m a. y y So, T = w + m a = m g + m a = m ( g + a ). y y y 100 kg[9.8 m/s 2 ( m/s 2)] 974 N. T = + = pply Newton's 2nd law to block of unknown mass. F = T w = m a. So, y y T = w + m a = m g + m a = m ( g + a ). Thus, m y y y =. ( g + a ) y Now, T = T = 974 N. Further, a = a = m/s 2. y y Hence, T m = 974 N = 99 kg. + (9.8 m/s m/s 2) 16
Newton s 3 Laws of Motion
Newton s 3 Laws of Motion 1. If F = 0 No change in motion 2. = ma Change in motion Fnet 3. F = F 1 on 2 2 on 1 Newton s First Law (Law of Inertia) An object will remain at rest or in a constant state of
More informationChapter 7 Newton s Third Law
Chapter 7 Newton s Third Law Chapter Goal: To use Newton s third law to understand interacting objects. Slide 7-2 Chapter 7 Preview Slide 7-3 Chapter 7 Preview Slide 7-4 Chapter 7 Preview Slide 7-6 Chapter
More informationChapter 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
More informationSection /07/2013. PHY131H1F University of Toronto Class 12 Preclass Video by Jason Harlow. Based on Knight 3 rd edition Ch. 7, pgs.
PHY131H1F University of Toronto Class 12 Preclass Video by Jason Harlow Section 7.1 Based on Knight 3 rd edition Ch. 7, pgs. 167-184 When a hammer hits a nail, it exerts a forward force on the nail At
More informationPHYSICS. Chapter 7 Lecture FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E RANDALL D. KNIGHT Pearson Education, Inc.
PHYSICS FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E Chapter 7 Lecture RANDALL D. KNIGHT Chapter 7 Newton s Third Law IN THIS CHAPTER, you will use Newton s third law to understand how objects
More informationGeneral Physics I Spring Forces and Newton s Laws of Motion
General Physics I Spring 2011 Forces and Newton s Laws of Motion 1 Forces and Interactions The central concept in understanding why things move is force. If a tractor pushes or pulls a trailer, the tractor
More informationIsaac Newton ( ) 1687 Published Principia Invented Calculus 3 Laws of Motion Universal Law of Gravity
Isaac Newton (1642-1727) 1687 Published Principia Invented Calculus 3 Laws of Motion Universal Law of Gravity Newton s First Law (Law of Inertia) An object will remain at rest or in a constant state of
More informationCHAPTER 4 NEWTON S LAWS OF MOTION
62 CHAPTER 4 NEWTON S LAWS O MOTION CHAPTER 4 NEWTON S LAWS O MOTION 63 Up to now we have described the motion of particles using quantities like displacement, velocity and acceleration. These quantities
More information8.01x Classical Mechanics, Fall 2016 Massachusetts Institute of Technology. Problem Set 2
8.01x Classical Mechanics, Fall 2016 Massachusetts Institute of Technology 1. Stacked Blocks Problem Set 2 Consider two blocks that are resting one on top of the other. The lower block has mass m 2 = 4.8
More informationPH201 Chapter 5 Solutions
PH201 Chapter 5 Solutions 5.4. Set Up: For each object use coordinates where +y is upward. Each object has Call the objects 1 and 2, with and Solve: (a) The free-body diagrams for each object are shown
More informationAP Physics 1 - Test 05 - Force and Motion
P Physics 1 - Test 05 - Force and Motion Score: 1. brick slides on a horizontal surface. Which of the following will increase the magnitude of the frictional force on it? Putting a second brick on top
More informationApplying Newton s Laws
Applying Newton s Laws Free Body Diagrams Draw and label the forces acting on the object. Examples of forces: weight, normal force, air resistance, friction, applied forces (like a push or pull) Velocity
More informationPhysics B Newton s Laws AP Review Packet
Force A force is a push or pull on an object. Forces cause an object to accelerate To speed up To slow down To change direction Unit: Newton (SI system) Newton s First Law The Law of Inertia. A body in
More information2. A 10 kg box is being pushed by a 100 N force 30 above the horizontal. The acceleration of the box is 5 m/s 2. What is the value of µ k?
Physics Whiteboard Forces with Friction 1. A 70 kg block is being pushed across a tabletop with a constant force of 350 N exerted in the direction of travel. If the coefficient of kinetic friction (µ k
More informationConsider the case of a 100 N. mass on a horizontal surface as shown below:
1.9.1 Introduction The study of friction is called: The force of friction is defined as: The force of friction acting between two surfaces has three properties: i) ii) iii) Consider the case of a 100 N.
More informationChapter 3 The Laws of motion. The Laws of motion
Chapter 3 The Laws of motion The Laws of motion The Concept of Force. Newton s First Law. Newton s Second Law. Newton s Third Law. Some Applications of Newton s Laws. 1 5.1 The Concept of Force Force:
More informationLecture 4. Newton s 3rd law and Friction
Lecture 4 Newton s 3rd law and Friction Newtons First Law or Law of Inertia If no net external force is applied to an object, its velocity will remain constant ("inert"). OR A body cannot change its state
More information4.2. Visualize: Assess: Note that the climber does not touch the sides of the crevasse so there are no forces from the crevasse walls.
4.1. Solve: A force is basically a push or a pull on an object. There are five basic characteristics of forces. (i) A force has an agent that is the direct and immediate source of the push or pull. (ii)
More informationEnd-of-Chapter Exercises
End-of-Chapter Exercises For all these exercises, assume that all strings are massless and all pulleys are both massless and frictionless. We will improve our model and learn how to account for the mass
More informationChapter 6 Dynamics I: Motion Along a Line
Chapter 6 Dynamics I: Motion Along a Line Chapter Goal: To learn how to solve linear force-and-motion problems. Slide 6-2 Chapter 6 Preview Slide 6-3 Chapter 6 Preview Slide 6-4 Chapter 6 Preview Slide
More information7.1 Interacting Systems p Action/reaction pairs p Newton s Third Law p Ropes and Pulleys p.
7.1 Interacting Systems p. 183-185 7.2 Action/reaction pairs p. 185-189 7.3 Newton s Third Law p. 189-194 7.4 Ropes and Pulleys p. 194-198 7.5 Interacting-system Problems p. 198-202 1 7.1 Interacting Systems
More informationWhat is a Force? Free-Body diagrams. Contact vs. At-a-Distance 11/28/2016. Forces and Newton s Laws of Motion
Forces and Newton s Laws of Motion What is a Force? In generic terms: a force is a push or a pull exerted on an object that could cause one of the following to occur: A linear acceleration of the object
More informationLecture Outline Chapter 6. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.
Lecture Outline Chapter 6 Physics, 4 th Edition James S. Walker Chapter 6 Applications of Newton s Laws Units of Chapter 6 Frictional Forces Strings and Springs Translational Equilibrium Connected Objects
More informationChapter 4. Forces and Newton s Laws of Motion. continued
Chapter 4 Forces and Newton s Laws of Motion continued Quiz 3 4.7 The Gravitational Force Newton s Law of Universal Gravitation Every particle in the universe exerts an attractive force on every other
More informationVISUAL PHYSICS ONLINE DYNAMICS TYPES OF FORCES FRICTION
VISUAL PHYSICS ONLINE DYNAMICS TYPES OF FORCES FRICTION Friction force: the force acting on the object which acts in a direction parallel to the surface. A simple model for friction F f is that it is proportional
More informationChapter 4 Force and Motion
Chapter 4 Force and Motion Units of Chapter 4 The Concepts of Force and Net Force Inertia and Newton s First Law of Motion Newton s Second Law of Motion Newton s Third Law of Motion More on Newton s Laws:
More informationThursday February 8. Write these equations in your notes if they re not already there. You will want them for Exam 1 & the Final.
Assignment 4 due Friday like almost every Friday Pre-class due 15min before class like every class Help Room: Here, 6-9pm Wed/Thurs SI: Morton 222, M&W 7:15-8:45pm Office Hours: 204 EAL, 10-11am Wed or
More informationHelp Desk: 9:00-5:00 Monday-Thursday, 9:00-noon Friday, in the lobby of MPHY.
Help Desk: 9:00-5:00 Monday-Thursday, 9:00-noon Friday, in the lobby of MPHY. SI (Supplemental Instructor): Thomas Leyden (thomasleyden@tamu.edu) 7:00-8:00pm, Sunday/Tuesday/Thursday, MPHY 333 Chapter
More informationChapter 4. Dynamics: Newton s Laws of Motion
Chapter 4 Dynamics: Newton s Laws of Motion Types of Forces: An Overview Examples of Nonfundamental Forces -- All of these are derived from the electroweak force: normal or support forces friction tension
More informationAnnouncements 24 Sep 2013
Announcements 24 Sep 2013 1. If you have questions on exam 1 2. Newton s 2 nd Law Problems: F m a. Inclined planes b. Pulleys c. Ropes d. Friction e. Etc Remember N2 is a blueprint for obtaining a useful
More informationForces and Motion in One Dimension
Nicholas J. Giordano www.cengage.com/physics/giordano Forces and Motion in One Dimension Applications of Newton s Laws We will learn how Newton s Laws apply in various situations We will begin with motion
More informationMain points of today s lecture: Normal force Newton s 3 d Law Frictional forces: kinetic friction: static friction Examples. Physic 231 Lecture 9
Main points of today s lecture: Normal force Newton s 3 d Law Frictional forces: kinetic friction: static friction Examples. Physic 3 Lecture 9 f N k = µ k f N s < µ s Atwood s machine Consider the Atwood
More informationUniversity Physics (Prof. David Flory) Chapt_06 Saturday, October 06, 2007 Page 1
University Physics (Prof. David Flory) Chapt_06 Saturday, October 06, 2007 Page 1 Name: Date: 1. A crate resting on a rough horizontal floor is to be moved horizontally. The coefficient of static friction
More informationCHAPTER 4 TEST REVIEW -- Answer Key
AP PHYSICS Name: Period: Date: DEVIL PHYSICS BADDEST CLASS ON CAMPUS 50 Multiple Choice 45 Single Response 5 Multi-Response Free Response 3 Short Free Response 2 Long Free Response AP EXAM CHAPTER TEST
More informationMini Exam # 1. You get them back in the the recitation section for which you are officially enrolled.
Mini Exam # 1 You get them back in the the recitation section for which you are officially enrolled. One third of you did very well ( 18 points out of 20). The average was 13.4. If you stay in average,
More informationReview: Advanced Applications of Newton's Laws
Review: Advanced Applications of Newton's Laws 1. The free-body diagram of a wagon being pulled along a horizontal surface is best represented by a. A d. D b. B e. E c. C 2. The free-body diagram of a
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
FLEX Physical Science AP Physics C Newton's Laws --- Conceptual Questions MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) You swing a bat and hit
More informationWelcome back to Physics 211
Welcome back to Physics 211 Today s agenda: Weight Friction Tension 07-1 1 Current assignments Thursday prelecture assignment. HW#7 due this Friday at 5 pm. 07-1 2 Summary To solve problems in mechanics,
More information1N the force that a 100g bar of chocolate exerts on your hand.
Forces: - - > cause change in motions Newton's first law = law of inertia In absence of a net external force acting upon it, a body will either remain at rest or continue in its rectilinear uniform motion.
More informationExample. F and W. Normal. F = 60cos 60 N = 30N. Block accelerates to the right. θ 1 F 1 F 2
Physic 3 Lecture 7 Newton s 3 d Law: When a body exerts a force on another, the second body exerts an equal oppositely directed force on the first body. Frictional forces: kinetic friction: fk = μk N static
More informationChapter Test A. Teacher Notes and Answers Forces and the Laws of Motion. Assessment
Assessment Chapter Test A Teacher Notes and Answers Forces and the Laws of Motion CHAPTER TEST A (GENERAL) 1. c 2. d 3. d 4. c 5. c 6. c 7. c 8. b 9. d 10. d 11. c 12. a 13. d 14. d 15. b 16. d 17. c 18.
More informationCause of Friction. Friction is caused by the microscopic roughness between surfaces like two gears locking together. S. Evans
Cause of Friction Friction is caused by the microscopic roughness between surfaces like two gears locking together. Factors Affecting Friction Factors affecting friction: 1) The condition of the surfaces
More informationA. B. C. D. E. v x. ΣF x
Q4.3 The graph to the right shows the velocity of an object as a function of time. Which of the graphs below best shows the net force versus time for this object? 0 v x t ΣF x ΣF x ΣF x ΣF x ΣF x 0 t 0
More informationLecture 6. Applying Newton s Laws Free body diagrams Friction
Lecture 6 Applying Newton s Laws Free body diagrams Friction ACT: Bowling on the Moon An astronaut on Earth kicks a bowling ball horizontally and hurts his foot. A year later, the same astronaut kicks
More informationCircle the correct answer. For those questions involving calculations, working MUST be shown to receive credit.
Dynamics Assignment 3 Name: Multiple Choice. Circle the correct answer. For those questions involving calculations, working MUST be shown to receive credit. 1. Which statement is always true regarding
More informationChapter 6 Applications of Newton s Laws. Copyright 2010 Pearson Education, Inc.
Chapter 6 Applications of Newton s Laws Units of Chapter 6 Frictional Forces Strings and Springs Translational Equilibrium Connected Objects Circular Motion 6-1 Frictional Forces Friction has its basis
More informationChapter 6. Force and Motion-II
Chapter 6 Force and Motion-II 6.2 Friction Frictional Forces Friction has its basis in surfaces that are not completely smooth: Frictional Forces The static frictional force keeps an object from starting
More informationPhysics 2211 ABC Quiz #3 Solutions Spring 2017
Physics 2211 ABC Quiz #3 Solutions Spring 2017 I. (16 points) A block of mass m b is suspended vertically on a ideal cord that then passes through a frictionless hole and is attached to a sphere of mass
More informationYou may use g = 10 m/s 2, sin 60 = 0.87, and cos 60 = 0.50.
1. A child pulls a 15kg sled containing a 5kg dog along a straight path on a horizontal surface. He exerts a force of a 55N on the sled at an angle of 20º above the horizontal. The coefficient of friction
More informationChapter 5 Lecture. Pearson Physics. Newton's Laws of Motion. Prepared by Chris Chiaverina Pearson Education, Inc.
Chapter 5 Lecture Pearson Physics Newton's Laws of Motion Prepared by Chris Chiaverina Chapter Contents Newton's Laws of Motion Applying Newton's Laws Friction Newton's Laws of Motion Two of the most important
More informationFind the acceleration of the train B Find the distance traveled during this 20 s? C D
75 A train with a mass of 25000 kg increases its speed from 10 m/s to 25 m/s in 20 seconds. Assume that the acceleration is constant and that you can neglect friction. A Find the acceleration of the train
More informationChapter Four Holt Physics. Forces and the Laws of Motion
Chapter Four Holt Physics Forces and the Laws of Motion Physics Force and the study of dynamics 1.Forces - a. Force - a push or a pull. It can change the motion of an object; start or stop movement; and,
More informationAP Physics: Newton's Laws 2
Assignment Due Date: December 12, 2011 AP Physics: Newton's Laws 2 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. A lamp with a mass m = 42.6 kg is hanging
More informationQuiz #7. T f k m A gsinθ = m A a N m A gcosθ = 0 f k = µ k N m B g T = m B a
Quiz #7 Vector The method used in 2 Dimensions is exactly the same in 3D; just keep one more components (Pythagorean theorem also still holds in higher dimensions as long as the space is Euclidean). 1)
More informationConcept of Force and Newton s Laws of Motion
Concept of Force and Newton s Laws of Motion 8.01 W02D2 Chapter 7 Newton s Laws of Motion, Sections 7.1-7.4 Chapter 8 Applications of Newton s Second Law, Sections 8.1-8.4.1 Announcements W02D3 Reading
More information2. Kinetic friction - The force that acts against an object s motion. - Occurs once static friction has been overcome and object is moving
Section 2.14: Friction Friction is needed to move. Without friction, a car would sit in one spot spinning its tires, and a person would not be able to step forward. However, the motion of an object along
More informationWS-CH-4 Motion and Force Show all your work and equations used. Isaac Newton ( )
AP PHYSICS 1 WS-CH-4 Motion and Force Show all your work and equations used. Isaac Newton (1643-1727) Isaac Newton was the greatest English mathematician of his generation. He laid the foundation for differential
More informationPhys101 Second Major-162 Zero Version Coordinator: Dr. Kunwar S. Saturday, March 25, 2017 Page: 1
Coordinator: Dr. Kunwar S. Saturday, March 25, 2017 Page: 1 Q1. Only two horizontal forces act on a 3.0 kg body that can move over a frictionless floor. One force is 20 N, acting due east, and the other
More informationChapter 05 Test A. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.
Class: Date: Chapter 05 Test A Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The SI unit of force preferred by scientists is the: a. kilogram. b. newton.
More informationChapter 5 Applying Newton s Laws
Chapter 5 Applying Newton s Laws In this chapter we will introduce further applications of Newton s 1 st and 2 nd law. In summary, all of the contact forces and action-at-a-distance forces will go on the
More informationActually, no perfectly frictionless surface exists. For two surfaces in contact, tangential forces, called friction forces, will develop if one
Chapter 8 Friction Actually, no perfectly frictionless surface exists. For two surfaces in contact, tangential forces, called friction forces, will develop if one attempts to move one relative to the other.
More information8.012 Physics I: Classical Mechanics Fall 2008
MIT OpenCourseWare http://ocw.mit.edu 8.012 Physics I: Classical Mechanics Fall 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. MASSACHUSETTS INSTITUTE
More informationBell Ringer: What is Newton s 3 rd Law? Which force acts downward? Which force acts upward when two bodies are in contact?
Bell Ringer: What is Newton s 3 rd Law? Which force acts downward? Which force acts upward when two bodies are in contact? Does the moon attract the Earth with the same force that the Earth attracts the
More informationThere are two main types of friction:
Section 4.15: Friction Friction is needed to move. Without friction, a car would sit in one spot spinning its tires, and a person would not be able to step forward. However, the motion of an object along
More informationSPH3U Practice Test. True/False Indicate whether the statement is true or false.
True/False Indicate whether the statement is true or false. 1. The reason your head feels like it jerks backward when pulling away from a stop sign is best explained by Newton's First Law. 2. An airplane
More informationDynamics Review Checklist
Dynamics Review Checklist Newton s Laws 2.1.1 Explain Newton s 1 st Law (the Law of Inertia) and the relationship between mass and inertia. Which of the following has the greatest amount of inertia? (a)
More informationPHYSICS 220 Lecture 04 Forces and Motion in 1 D Textbook Sections
PHYSICS 220 Lecture 04 Forces and Motion in 1 D Textbook Sections 3.2 3.6 Lecture 4 Purdue University, Physics 220 1 Last Lecture Constant Acceleration x = x 0 + v 0 t + ½ at 2 v = v 0 + at Overview v
More informationGeneral Physics I Work & Energy
General Physics I Work & Energy Forms of Energy Kinetic: Energy of motion. A car on the highway has kinetic energy. We have to remove this energy to stop it. The brakes of a car get HOT! This is an example
More information4.1.1 Extra Practice 4.1 Analyze the effects of a uniform force (magnitude and direction.)
4.1.1 Extra Practice 4.1 Analyze the effects of a uniform force (magnitude and direction.) Frictional Forces LEVEL 2 1. (HRW 6-3) A bedroom bureau with a mass of 45 kg, including drawers and clothing,
More informationLECTURE 12 FRICTION, STRINGS & SPRINGS. Instructor: Kazumi Tolich
LECTURE 12 FRICTION, STRINGS & SPRINGS Instructor: Kazumi Tolich Lecture 12 2! Reading chapter 6-1 to 6-4! Friction " Static friction " Kinetic friction! Strings! Pulleys! Springs Origin of friction 3!!
More informationForces & Newton s Laws FR Practice Problems
1) A drag-racing car speeds up from rest to 22 m/s in 2 s. The car has mass 800 kg; the driver has mass 80 kg. a) Calculate the acceleration of the car. b) Calculate the net force on the car. c) Which
More information1 In the absence of a net force, a moving object will. slow down and eventually stop stop immediately turn right move with constant velocity turn left
Slide 1 / 51 1 In the absence of a net force, a moving object will slow down and eventually stop stop immediately turn right move with constant velocity turn left Slide 2 / 51 2 When a cat sleeps on a
More informationName Period Date. 75 kg. Horizontal, frictionless surface. Label a coordinate system, write the formula, substitute and solve.
Example Problems 5.3 Net Force E1. Two horizontal forces, 225 N and 165 N, are exerted in the same direction on a 75 kg crate as shown below. Find the net force and the acceleration of the crate. 165 N
More informationChapter 6. Force and Motion II
Chapter 6 Force and Motion II 6 Force and Motion II 2 Announcement: Sample Answer Key 3 4 6-2 Friction Force Question: If the friction were absent, what would happen? Answer: You could not stop without
More informationQ16.: A 5.0 kg block is lowered with a downward acceleration of 2.8 m/s 2 by means of a rope. The force of the block on the rope is:(35 N, down)
Old Exam Question Ch. 5 T072 Q13.Two blocks of mass m 1 = 24.0 kg and m 2, respectively, are connected by a light string that passes over a massless pulley as shown in Fig. 2. If the tension in the string
More informationPHYS 101 Previous Exam Problems. Force & Motion I
PHYS 101 Previous Exam Problems CHAPTER 5 Force & Motion I Newton s Laws Vertical motion Horizontal motion Mixed forces Contact forces Inclines General problems 1. A 5.0-kg block is lowered with a downward
More informationDynamics Review Checklist
Dynamics Review Checklist Newton s Laws 2.1.1 Explain Newton s 1 st Law (the Law of Inertia) and the relationship between mass and inertia. Which of the following has the greatest amount of inertia? (a)
More informationIntroduction to Mechanics Friction Examples Friction Springs
Introduction to Mechanics Friction Examples Friction Springs Lana Sheridan De Anza College Mar 7, 2018 Last time kinetic and static friction friction examples Overview one more friction example springs
More informationName Date Period PROBLEM SET: ROTATIONAL DYNAMICS
Accelerated Physics Rotational Dynamics Problem Set Page 1 of 5 Name Date Period PROBLEM SET: ROTATIONAL DYNAMICS Directions: Show all work on a separate piece of paper. Box your final answer. Don t forget
More informationPSI AP Physics B Dynamics
PSI AP Physics B Dynamics Multiple-Choice questions 1. After firing a cannon ball, the cannon moves in the opposite direction from the ball. This an example of: A. Newton s First Law B. Newton s Second
More informationPHYSICS - CLUTCH CH 04: INTRO TO FORCES (DYNAMICS)
!! www.clutchprep.com FORCE, APPLIED FORCE, TENSION A force is either a push or a pull. Unit = ( ) - We ll represent all forces as a We ll refer to generic forces as forces. - Usually on an object by a
More informationReview of Lectures 1, 2 and 3
Physics 22000 General Physics Lecture 5 Applying Newton s Laws Fall 2016 Semester Prof. Matthew Jones 1 Review of Lectures 1, 2 and 3 Algebraic description of linear motion with constant acceleration:
More informationPhysics 207 Lecture 7. Lecture 7
Lecture 7 "Professor Goddard does not know the relation between action and reaction and the need to have something better than a vacuum against which to react. He seems to lack the basic knowledge ladled
More informationPHYS1100 Practice problem set, Chapter 8: 5, 9, 14, 20, 22, 25, 28, 30, 34, 35, 40, 44
PHYS00 Practice problem set, Chapter 8: 5, 9, 4, 0,, 5, 8, 30, 34, 35, 40, 44 8.5. Solve: The top figure shows the pulle (P), block A, block B, the surface S of the incline, the rope (R), and the earth
More informationExam 1 Stats: Average: 60% Approximate letter grade? Add 10%-12% (This is not a curve) This takes into account the HW, Lab, and Grade Replacement.
Lec 11 Return Exam1 Intro Forces Tuesday, February 19, 2019 1:52 PM Exam 1 Stats: Average: 60% Approximate letter grade? Add 10%-12% (This is not a curve) This takes into account the HW, Lab, and Grade
More informationPreClass Notes: Chapter 5, Sections 5.4,5.5
PreClass Notes: Chapter 5, Sections 5.4,5.5 From Essential University Physics 3 rd Edition by Richard Wolfson, Middlebury College 2016 by Pearson Education, Inc. Narration and extra little notes by Jason
More informationForce. The cause of an acceleration or change in an object s motion. Any kind of a push or pull on an object.
Force The cause of an acceleration or change in an object s motion. Any kind of a push or pull on an object. Forces do not always give rise to motion. Forces can be equal and opposite. Force is a vector
More information24/06/13 Forces ( F.Robilliard) 1
R Fr F W 24/06/13 Forces ( F.Robilliard) 1 Mass: So far, in our studies of mechanics, we have considered the motion of idealised particles moving geometrically through space. Why a particular particle
More informationMarch 10, P12 Inclined Planes.notebook. Physics 12. Inclined Planes. Push it Up Song
Physics 12 Inclined Planes Push it Up Song 1 Bell Work A box is pushed up a ramp at constant velocity. Draw a neatly labeled FBD showing all of the forces acting on the box. direction of motion θ F p F
More informationNewton s First Law and IRFs
Goals: Physics 207, Lecture 6, Sept. 22 Recognize different types of forces and know how they act on an object in a particle representation Identify forces and draw a Free Body Diagram Solve 1D and 2D
More informationChapter 6. Applications of Newton s Laws
Chapter 6 Applications of Newton s Laws P. Lam 7_11_2018 Learning Goals for Chapter 5 Learn how to apply Newton s First Law & Second Law. Understand the cause of apparent weight and weightlessness Learn
More informationDynamics Review Checklist
Dynamics Review Checklist Newton s Laws 2.1.1 Explain Newton s 1 st Law (the Law of Inertia) and the relationship between mass and inertia. Which of the following has the greatest amount of inertia? (a)
More informationThe Concept of Force Newton s First Law and Inertial Frames Mass Newton s Second Law The Gravitational Force and Weight Newton s Third Law Analysis
The Laws of Motion The Concept of Force Newton s First Law and Inertial Frames Mass Newton s Second Law The Gravitational Force and Weight Newton s Third Law Analysis Models using Newton s Second Law Forces
More information6. Which graph best represents the motion of an object that is not in equilibrium as it travels along a straight line? A) B)
1. The data table below lists the mass and speed of four different objects. 6. Which graph best represents the motion of an object that is not in equilibrium as it travels along a straight line? Which
More informationReading Quiz. Chapter 5. Physics 111, Concordia College
Reading Quiz Chapter 5 1. The coefficient of static friction is A. smaller than the coefficient of kinetic friction. B. equal to the coefficient of kinetic friction. C. larger than the coefficient of kinetic
More informationWebreview practice test. Forces (again)
Please do not write on test. ID A Webreview 4.3 - practice test. Forces (again) Multiple Choice Identify the choice that best completes the statement or answers the question. 1. A 5.0-kg mass is suspended
More informationHSC PHYSICS ONLINE B F BA. repulsion between two negatively charged objects. attraction between a negative charge and a positive charge
HSC PHYSICS ONLINE DYNAMICS TYPES O ORCES Electrostatic force (force mediated by a field - long range: action at a distance) the attractive or repulsion between two stationary charged objects. AB A B BA
More informationChapter 5 Force and Motion
Chapter 5 Force and Motion Chapter Goal: To establish a connection between force and motion. Slide 5-2 Chapter 5 Preview Slide 5-3 Chapter 5 Preview Slide 5-4 Chapter 5 Preview Slide 5-5 Chapter 5 Preview
More informationPHYSICS - CLUTCH CH 05: FRICTION, INCLINES, SYSTEMS.
!! www.clutchprep.co INTRO TO FRICTION Friction happens when two surfaces are in contact f = μ =. KINETIC FRICTION (v 0 *): STATIC FRICTION (v 0 *): - Happens when ANY object slides/skids/slips. * = Point
More informationAP Physics C: Work, Energy, and Power Practice
AP Physics C: Work, Energy, and Power Practice 1981M2. A swing seat of mass M is connected to a fixed point P by a massless cord of length L. A child also of mass M sits on the seat and begins to swing
More information