# Applying Newton s Laws

Save this PDF as:

Size: px
Start display at page: ## Transcription

1 Chapter 5 Applying Newton s Laws PowerPoint Lectures for University Physics, Twelfth Edition Hugh D. Young and Roger A. Freedman Lectures by James Pazun

2 Goals for Chapter 5 To use and apply Newton s Laws Connect these laws to Kinematics To study friction and fluid resistance To consider forces in circular motion First in Equilibrium (Newton s First Law) Then, in non-equilibrium (Second Law)

3 Using Newton s First Law when forces are in equilibrium

4 Netwon s laws problems 1. Draw the free body diagram (only forces ON the object, not the ones exerted by the object) 2. Decompose the forces along X and Y directions 3. Write down Newton s 2 nd laws for each direction and each object 4. If more than one object determine their relation (tension forces, acceleration, etc.)

5 1-D equilibrium Consider an athlete hanging on a massless rope.

6 Figure 5.3 PowerPoint Lectures for University Physics, Twelfth Edition Hugh D. Young and Roger A. Freedman Lectures by James Pazun

7 A crate on an inclined plane An object on an inclined plane will have components of force in x and y space.

8 Person in an elevator Moving in an arbitrary direction

9 Connected - Two bodies with same acceleration magnitude Draw the two-free body diagrams. The tension from the mass hanging is the same force that draws the cart up the ramp.

10 Box on an inclined plane A box with mass m is placed on a frictionless incline with angle q and is allowed to slide down. a) What is the normal force? b) What is the acceleration of the box? c) How long does it take to fall if the ramp has a length L? F N q mg cosq q mg sinq w B =mg x : mgsinq = ma x y : F N - mgcosq = 0 a x = gsinq

11 Watch for this common error A good road sign is to be sure that the normal force comes out perpendicular to the surface.

12 Friction Two types of friction: 1. Kinetic: The friction force that slows things down 2. Static: The force that makes it hard to even get things moving

13 Refrigerator If you push a refrigerator when there is no friction what happens? In the real world what happens? Especially when it s fully loaded and on a sticky kitchen floor? When does static friction kick in? When does kinetic friction kick in?

14 Frictional forces, kinetic and static Figures 5.17 and 5.18 Friction can keep an object from moving or slow its motion from what we last calculated on an ideal, frictionless surface. Microscopic imperfections cause nonideal motion.

15 Applied force is proportional until the object moves Figure 5.19 Notice the transition between static and kinetic friction. F f-s <μ s F N Ff-k=μkFN If you use the maximum static friction in all cases, there is a big problem!

16 Static Friction This is more complicated For static friction, the friction force can vary F Friction µ Static F Normal Example of the refrigerator: If I don t push, what is the static friction force? What if I push a little?

17 Kinetic Friction For kinetic friction, it turns out that the larger the Normal Force the larger the friction. We can write F Friction = µ Kinetic F Normal Warning: Here µ is a constant THIS IS NOT A VECTOR EQUATION!

18 Notice the effect of friction in horizontal motion Moving a 500 N crate has two parts: getting the motion to begin and then the effect of friction on constant velocity motion.

19 Pulling Against Friction A box of mass m is on a surface with coefficient of kinetic friction mu. You pull with constant force F P at angle Q. The box does not leave the surface and moves to the right. 1. What is the acceleration? 2. What angle maximizes the acceleration? Q Þ x : x : F P cosq - µ K F N = ma x y : F N + F P sinq - mg = 0 F N = mg - F P sinq F P cosq - µ K (mg - F P sinq) = ma x a x = F P m cosq - µ Kg + µ K F P m sinq d(a x ) = - F P dq q max m sinq + µ K F P m cosq = 0 Þ q max = tan -1 µ K

20 Is it better to push or pull a sled? You can pull or push a sled with the same force magnitude, F P, but different angles Q, as shown in the figures. Assuming the sled doesn t leave the ground and has a constant coefficient of friction, m, which is better? F P

21 Box on an inclined plane 2 Same problem as before, but now friction is not negligible and the coefficient of friction is µ. The inclined plane is adjustable and we change q from 0 to 90 degrees. Mass is known and is equal to m. Calculate and draw a graph of: Friction force as a function of q Acceleration of the box as a function of q F f <μf N mg cosq q F N w B =mg If q>q max q x : mgsinq - µ K F N = ma x If static x : mgsinq - F f = 0 y : F N - mgcosq = 0 mg sinq Þ F f = mgsinq µ s F N = mgsinq max µ s mgcosq max = mgsinq max tanq max = µ s y : F N - mgcosq = 0 Þ mgsinq - µ k mgcosq = ma x

22 Friction

23 Friction

24 Friction

25 Friction

26 The dynamics of uniform circular motion In uniform circular motion, both the acceleration and force are centripetal. When going in a circle the choice of coordinates is NOT optional. One of the axis has to point towards the center and in this case å F = ma r c = m v2 R

27 Netwon s laws problems 1. Draw the free body diagram (only forces ON the object, not the ones exerted by the object) 2. Choose coordinates (chose one along the direction of motion if going straight) for each object. Choose + in the direction of motion. IF there is circular motion ONE of the axis has to point towards the center (+ towards center). Decompose the forces that are not along the coordinates 3. Write down Newton s 2 nd laws for each direction and each object. For the one going around a circle the acceleration is a c =v 2 /R. 4. If more than one object determine their relation (force, acceleration, etc.)

28 Examining a misnomer People have adopted the pop-culture use of centrifugal force but it really results from reference frames. It is fictional and results from a car turning while a person continues in straight-line motion (for example).

29 Hanging ball going on circles For the situation below, if only L and the angle are known, (a) What is the tension in the cord? (b) What is the time it takes the ball to go around once? å F r = F T sin b = m 2 v R = m 2 v Lsin b å F y = F T cos b - mg = 0 F T = mg cosb Þ mg cosb sin b = m 4p 2 Lsin b T 2 T = 2p L cos b g

30 Rounding unbanked curve: maximum speed Given a coefficient of static friction, μ s, what is the maximum speed the car can go around the curve without skidding? å F r = F f = m v2 R åf y = F N - mg = 0 F f -max = µ s F N Þ µ s F N = m v 2 max R Þ v max = µ s gr

31 Rounding banked curve: maximum speed What is the angle you need to go around the curve at speed v without friction? å F r = F N sinb = m v2 R åf r = F N cosb - mg = 0 F N = mg cosb Þ mg v2 sin b = mgtanb = m cosb R Þ v = gr tanb

32 Circular and linear motion (2 Objects) The table is frictionless. What must the velocity be for the hanging mass M (2 kg) to remain stationary? Radius is 20 cm. The small mass m is 1 kg.

33 Q5.11 A sled moves on essentially frictionless ice. It is attached by a rope to a vertical post set in the ice. Once given a push, the sled moves around the post at constant speed in a circle of radius R. If the rope breaks, A. the sled will keep moving in a circle. B. the sled will move on a curved path, but not a circle. C. the sled will follow a curved path for a while, then move in a straight line. D. the sled will move in a straight line.

34 Q5.12 A pendulum bob of mass m is attached to the ceiling by a thin wire of length L. The bob moves at constant speed in a horizontal circle of radius R, with the wire making a constant angle with the vertical. The tension in the wire A. is greater than mg. B. is equal to mg. C. is less than mg. D. could be two of the above, depending on the values of m, L, R, and. E. could be all three of the above, depending on the values of m, L, R, and.

35 Hanging balls What is the tension on each string and the force that the balls exert on each other? The mass of each mass is 15 kg and the diameter 25 cm. This example was worked out in class 25 cm Try to do an example with different masses, e.g., one is 10 Kg and the other 20 Kg.

36 Q5.12 A pendulum bob of mass m is attached to the ceiling by a thin wire of length L. The bob moves at constant speed in a horizontal circle of radius R, with the wire making a constant angle b with the vertical. The tension in the wire A. is greater than mg. B. is equal to mg. C. is less than mg. D. is any of the above, depending on the bob s speed v.

37 Q5.13 A pendulum of length L with a bob of mass m swings back and forth. At the low point of its motion (point Q ), the tension in the string is (3/2)mg. What is the speed of the bob at this point? A. 2 gl B. 2gL C. gl P R D. gl 2 Q E. gl 2

38 Forces Assume no friction. Which way will it move? a) Left b) Right c) Stays balanced and will not move

39 Q5.5 A lightweight crate (A) and a heavy crate (B) are side by side on a frictionless horizontal surface. You are applying a horizontal force F to crate A. Which of the following forces should be included in a free-body diagram for crate B? A. the weight of crate B B. the force of crate B on crate A C. the force F that you exert F A B D. the acceleration of crate B E. more than one of the above

40 Q5.6 A toboggan of weight w (including the passengers) slides down a hill of angle a at a constant speed. Which statement about the normal force on the toboggan (magnitude n) is correct? A. n = w B. n > w C. n < w D. not enough information given to decide

41 Q5.9 Blocks A and C are connected by a string as shown. When released, block A accelerates to the right and block C accelerates downward. There is friction between blocks A and B, but not enough to prevent block B from slipping. If you stood next to the table during the time that block B is slipping on top of block A, you would see A. block B accelerating to the right. B. block B accelerating to the left. C. block B moving at constant speed to the right. D. block B moving at constant speed to the left.

42 A more complicated pulley problem Here there is no friction. What is the acceleration of each mass? - F N T T T - m 1 g + m 2 g x : å F x = T = m 1 a 1 y : å F y = F N - m 1 g = 0 + x : 0 = 0 y : å F y = m 2 g - 2T = m 2 a 2 The next key thing to notice is that a 1 is twice a 2 : this is because the length of the cord is conserved and if object 1 moves 1 meter to the left then object 2 moves 1/2 a meter down. Then: T = m 1 a 1 m 2 g - 2T = m 2 a 1 2 a Þ m 2 g - 2m 1 a 1 = m m Þ a 1 = 2 g and a 2m 1 + (m 2 /2) 2 = m 2 g 4m 1 + m 2

### Applying Newton s Laws Chapter 5 Applying Newton s Laws PowerPoint Lectures for University Physics, Twelfth Edition Hugh D. Young and Roger A. Freedman Lectures by James Pazun Copyright 2008 Pearson Education Inc., publishing

### Applying Newton s Laws Chapter 5 Applying Newton s Laws PowerPoint Lectures for University Physics, Thirteenth Edition Hugh D. Young and Roger A. Freedman Lectures by Wayne Anderson Copyright 2012 Pearson Education Inc. To use

### Forces on an inclined plane Section 2.2 Forces on an inclined plane Section 2.2 Examples of inclined planes Previous Knowledge Since some of the incline problems lets review friction (both kinetic and static) and normal force. Friction Friction

### Lecture PowerPoints. Chapter 5 Physics for Scientists & Engineers, with Modern Physics, 4 th edition. Giancoli Lecture PowerPoints Chapter 5 Physics for Scientists & Engineers, with Modern Physics, 4 th edition 2009 Pearson Education, Inc. This work is protected by United States copyright laws and is provided solely

### Physics 111: Mechanics Lecture 5 Physics 111: Mechanics Lecture 5 Bin Chen NJIT Physics Department Forces of Friction: f q When an object is in motion on a surface or through a viscous medium, there will be a resistance to the motion.

### Chapter 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

### Lecture 5. Dynamics. Forces: Newton s First and Second Lecture 5 Dynamics. Forces: Newton s First and Second What is a force? It s a pull or a push: F F Force is a quantitative description of the interaction between two physical bodies that causes them to

### You 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

### Review: 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

### PHYS 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

### 66 Chapter 6: FORCE AND MOTION II Chapter 6: FORCE AND MOTION II 1 A brick slides on a horizontal surface Which of the following will increase the magnitude of the frictional force on it? A Putting a second brick on top B Decreasing the

### Physics 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

### Be on time Switch off mobile phones. Put away laptops. Being present = Participating actively A couple of house rules Be on time Switch off mobile phones Put away laptops Being present = Participating actively http://www.phys.tue.nl/nfcmr/natuur/collegenatuur.html Chapter 4 Newton s Laws of Motion

### A. 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

### Figure 5.1a, b IDENTIFY: Apply to the car. EXECUTE: gives.. EVALUATE: The force required is less than the weight of the car by the factor. 51 IDENTIFY: for each object Apply to each weight and to the pulley SET UP: Take upward The pulley has negligible mass Let be the tension in the rope and let be the tension in the chain EXECUTE: (a) The

### Physics 101 Lecture 5 Newton`s Laws Physics 101 Lecture 5 Newton`s Laws Dr. Ali ÖVGÜN EMU Physics Department The Laws of Motion q Newton s first law q Force q Mass q Newton s second law q Newton s third law qfrictional forces q Examples

### Chapter 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:

### (a) On the dots below that represent the students, draw and label free-body diagrams showing the forces on Student A and on Student B. 2003 B1. (15 points) A rope of negligible mass passes over a pulley of negligible mass attached to the ceiling, as shown above. One end of the rope is held by Student A of mass 70 kg, who is at rest on

### Reading 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

### Friction is always opposite to the direction of motion. 6. Forces and Motion-II Friction: The resistance between two surfaces when attempting to slide one object across the other. Friction is due to interactions at molecular level where rough edges bond together:

### HATZIC SECONDARY SCHOOL HATZIC SECONDARY SCHOOL PROVINCIAL EXAMINATION ASSIGNMENT VECTOR DYNAMICS MULTIPLE CHOICE / 45 OPEN ENDED / 75 TOTAL / 120 NAME: 1. Unless acted on by an external net force, an object will stay at rest

### Newton s Laws. Newton s Laws http://mathsforeurope.digibel.be/images Forces and Equilibrium If the net force on a body is zero, it is in equilibrium. dynamic equilibrium: moving relative to us static equilibrium: appears

### 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 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

### Exam 2 Phys Fall 2002 Version A. Name ID Section Closed book exam - Calculators are allowed. Only the official formula sheet downloaded from the course web page can be used. You are allowed to write notes on the back of the formula sheet. Use the scantron

### Webreview 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

### AP Physics Free Response Practice Dynamics AP Physics Free Response Practice Dynamics 14) In the system shown above, the block of mass M 1 is on a rough horizontal table. The string that attaches it to the block of mass M 2 passes over a frictionless

### Q16.: 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

### PHYSICS 231 Laws of motion PHY 231 PHYSICS 231 Laws of motion 1 Newton s Laws First Law: If the net force exerted on an object is zero the object continues in its original state of motion; if it was at rest, it remains at rest. If it was

### Chapter 4: Newton s Second Law F = m a. F = m a (4.2) Lecture 7: Newton s Laws and Their Applications 1 Chapter 4: Newton s Second Law F = m a First Law: The Law of Inertia An object at rest will remain at rest unless, until acted upon by an external force.

### 1. A sphere with a radius of 1.7 cm has a volume of: A) m 3 B) m 3 C) m 3 D) 0.11 m 3 E) 21 m 3 1. A sphere with a radius of 1.7 cm has a volume of: A) 2.1 10 5 m 3 B) 9.1 10 4 m 3 C) 3.6 10 3 m 3 D) 0.11 m 3 E) 21 m 3 2. A 25-N crate slides down a frictionless incline that is 25 above the horizontal.

### Welcome 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,

### Physics 201 Lecture 16 Physics 01 Lecture 16 Agenda: l Review for exam Lecture 16 Newton s Laws Three blocks are connected on the table as shown. The table has a coefficient of kinetic friction of 0.350, the masses are m 1 =

### WS-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

### AP Physics 1: MIDTERM REVIEW OVER UNITS 2-4: KINEMATICS, DYNAMICS, FORCE & MOTION, WORK & POWER MIDTERM REVIEW AP Physics 1 McNutt Name: Date: Period: AP Physics 1: MIDTERM REVIEW OVER UNITS 2-4: KINEMATICS, DYNAMICS, FORCE & MOTION, WORK & POWER 1.) A car starts from rest and uniformly accelerates

### MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) You are standing in a moving bus, facing forward, and you suddenly fall forward as the

### End-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

### Chapters 5-6. Dynamics: Forces and Newton s Laws of Motion. Applications Chapters 5-6 Dynamics: orces and Newton s Laws of Motion. Applications That is, describing why objects move orces Newton s 1 st Law Newton s 2 nd Law Newton s 3 rd Law Examples of orces: Weight, Normal,

### PH201 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

### Old Exam. Question Chapter 7 072 Old Exam. Question Chapter 7 072 Q1.Fig 1 shows a simple pendulum, consisting of a ball of mass M = 0.50 kg, attached to one end of a massless string of length L = 1.5 m. The other end is fixed. If the

### Chapter 5. The Laws of Motion Chapter 5 The Laws of Motion The Laws of Motion The description of an object in motion included its position, velocity, and acceleration. There was no consideration of what might influence that motion.

### Physics 23 Exam 2 March 3, 2009 Use the following to answer question 1: A stationary 4-kg shell explodes into three pieces. Two of the fragments have a mass of 1 kg each and move along the paths shown with a speed of 10 m/s. The third

### Work and energy. 15 m. c. Find the work done by the normal force exerted by the incline on the crate. Work and energy 1. A 10.0-kg crate is pulled 15.0 m up along a frictionless incline as shown in the figure below. The crate starts at rest and has a final speed of 6.00 m/s. motor 15 m 5 a. Draw the free-body

### Lecture 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

### CHAPTER 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

### Applying 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

### Unit 2: Vector Dynamics Multiple Choice Portion Unit 2: Vector Dynamics 1. Which one of the following best describes the motion of a projectile close to the surface of the Earth? (Assume no friction) Vertical Acceleration Horizontal

### PSI 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

### Physics 53 Summer Exam I. Solutions Exam I Solutions In questions or problems not requiring numerical answers, express the answers in terms of the symbols for the quantities given, and standard constants such as g. In numerical questions

### Announcements 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

### Free-body diagrams. a. Find the acceleration of mass 2. b. Determine the magnitude of the tension in the string. Free-body diagrams 1. wo blocks of masses m1 = 5.0 kg and m =.0 kg hang on both sides of an incline, connected through an ideal, massless string that goes through an ideal, massless pulley, as shown below.

### y(t) = y 0 t! 1 2 gt 2. With y(t final ) = 0, we can solve this for v 0 : v 0 A ĵ. With A! ĵ =!2 and A! = (2) 2 + (! 1. The angle between the vector! A = 3î! 2 ĵ! 5 ˆk and the positive y axis, in degrees, is closest to: A) 19 B) 71 C) 90 D) 109 E) 161 The dot product between the vector! A = 3î! 2 ĵ! 5 ˆk and the unit

### 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

### Galileo & Friction 2000 yrs prior to inertia idea, the popular belief was that all objects want to come to a rest. BUT 1600's: Galileo reasoned that Galileo & Friction 2000 yrs prior to inertia idea, the popular belief was that all objects want to come to a rest. BUT 1600's: Galileo reasoned that moving objects eventually stop only because of a force

### W = 750 m. PHYS 101 SP17 Exam 1 BASE (A) PHYS 101 Exams. The next two questions pertain to the situation described below. PHYS 101 Exams PHYS 101 SP17 Exa BASE (A) The next two questions pertain to the situation described below. A boat is crossing a river with a speed to the water. The river is flowing at a speed W = 750

### Regents Physics. Physics Midterm Review - Multiple Choice Problems Name Physics Midterm Review - Multiple Choice Problems Regents Physics 1. A car traveling on a straight road at 15.0 meters per second accelerates uniformly to a speed of 21.0 meters per second in 12.0

### The Laws of Motion. Newton s first law Force Mass Newton s second law Gravitational Force Newton s third law Examples The Laws of Motion Newton s first law Force Mass Newton s second law Gravitational Force Newton s third law Examples Gravitational Force Gravitational force is a vector Expressed by Newton s Law of Universal

### University 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

### dt 2 x = r cos(θ) y = r sin(θ) r = x 2 + y 2 tan(θ) = y x A circle = πr 2 v = v i + at a dv dt = d2 x dt 2 A sphere = 4πr 2 x = x i + v i t + 1 2 at2 x = r cos(θ) V sphere = 4 3 πr3 v 2 = v 2 i + 2a x F = ma R = v2 sin(2θ) g y = r sin(θ) r = x 2 + y 2 tan(θ) = y x a c = v2 r

### Circular Motion. 1 Circular Motion www.njctl.org 2 Topics of Uniform Circular Motion (UCM) Kinematics of UCM Click on the topic to go to that section Period, Frequency, and Rotational Velocity Dynamics of UCM Vertical

### Ch 6 Using Newton s Laws. Applications to mass, weight, friction, air resistance, and periodic motion Ch 6 Using Newton s Laws Applications to mass, weight, friction, air resistance, and periodic motion Newton s 2 nd Law Applied Galileo hypothesized that all objects gain speed at the same rate (have the

### Hint 1. The direction of acceleration can be determined from Newton's second law Chapter 5 [ Edit ] Overview Summary View Diagnostics View Print View with Answers Chapter 5 Due: 11:59pm on Sunday, October 2, 2016 To understand how points are awarded, read the Grading Policy for this

### Chapter 8: Newton s Laws Applied to Circular Motion Chapter 8: Newton s Laws Applied to Circular Motion Centrifugal Force is Fictitious? F actual = Centripetal Force F fictitious = Centrifugal Force Center FLEEing Centrifugal Force is Fictitious? Center

### CHAPTER 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

### Show all work in answering the following questions. Partial credit may be given for problems involving calculations. Physics 3210, Spring 2017 Exam #1 Name: Signature: UID: Please read the following before continuing: Show all work in answering the following questions. Partial credit may be given for problems involving

### = 40 N. Q = 60 O m s,k Sample Exam #2 Technical Physics Multiple Choice ( 6 Points Each ): F app = 40 N 20 kg Q = 60 O = 0 1. A 20 kg box is pulled along a frictionless floor with an applied force of 40 N. The applied force

### Kinematics and Dynamics AP PHYS 1 Test Review Kinematics and Dynamics Name: Other Useful Site: http://www.aplusphysics.com/ap1/ap1- supp.html 2015-16 AP Physics: Kinematics Study Guide The study guide will help you review all

### Chapter 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

### AP Physics C: Mechanics Practice (Newton s Laws including friction, resistive forces, and centripetal force). AP Physics C: Mechanics Practice (Newton s Laws including friction, resistive forces, and centripetal force). 1981M1. A block of mass m, acted on by a force of magnitude F directed horizontally to the

### The next two questions pertain to the situation described below. PHYS 101 Exams PHYS 101 SP17 Exam 1 PRINT (A) The next two questions pertain to the situation described below. A boat is crossing a river with a speed v b = 8.3 m/s relative to the water. The river is

### Physics 201, Midterm Exam 2, Fall Answer Key Physics 201, Midterm Exam 2, Fall 2006 Answer Key 1) A constant force is applied to a body that is already moving. The force is directed at an angle of 60 degrees to the direction of the body s velocity.

### MULTIPLE 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

### Lecture PowerPoints. Chapter 4 Physics: for Scientists & Engineers, with Modern Physics, 4th edition Giancoli Lecture PowerPoints Chapter 4 Physics: for Scientists & Engineers, with Modern Physics, 4th edition Giancoli 2009 Pearson Education, Inc. This work is protected by United States copyright laws and is provided

### C) D) 2. The diagram below shows a worker using a rope to pull a cart. 1. Which graph best represents the relationship between the acceleration of an object falling freely near the surface of Earth and the time that it falls? 2. The diagram below shows a worker using a rope

### MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Diagram 1 A) B - A. B) A - B. C) A + B. D) A B. Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) In the diagram shown, the unknown vector is 1) Diagram 1 A) B - A. B) A - B. C) A + B.

### Newton 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

### Physics for Scientist and Engineers third edition Newton s Laws. Example Problem. Variables. Drawing. Solution. Answer: O, 10 N, 20 N, 38N, 39N, 29N Our 10.0 kg mystery bx rest on a horizontal floor. The coefficent of static friction is µs= 0.40 and the coefficent of kinetic friction is µk= 0.30. Determine the force of friction Ffr acting on the box

### variable Formula S or v SI variable Formula S or v SI 4. How is a Newton defined? What does a Newton equal in pounds? Newton s Laws 1 1. Define mass variable Formula S or v SI 2. Define inertia, how is inertia related to mass 3. What is a Force? variable Formula S or v SI 4. How is a Newton defined? What does a Newton

### REVIEW SET 2 MIDTERM 2 Physics 2010 Fall 2009 Sid Rudolph REVIEW SET 2 MIDTERM 2 1. In a popular amusement park ride, a rotating cylinder of radius 15.0 m rotates with an angular speed of 8.0 rad/s. The floor of then drops away

### Circular Motion (Chapter 5) Circular Motion (Chapter 5) So far we have focused on linear motion or motion under gravity (free-fall). Question: What happens when a ball is twirled around on a string at constant speed? Ans: Its velocity

### AP Mechanics Summer Assignment 2012-2013 AP Mechanics Summer Assignment To be completed in summer Submit for grade in September Name: Date: Equations: Kinematics (For #1 and #2 questions: use following equations only. Need to show derivation

### Physics Mechanics. Lecture 11 Newton s Laws - part 2 Physics 170 - Mechanics Lecture 11 Newton s Laws - part 2 Newton s Second Law of Motion An object may have several forces acting on it; the acceleration is due to the net force: Newton s Second Law of

### Review PHYS114 Chapters 4-7 Review PHYS114 Chapters 4-7 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A 27 kg object is accelerated at a rate of 1.7 m/s 2. What force does

### Lecture 10. Example: Friction and Motion Lecture 10 Goals: Exploit Newton s 3 rd Law in problems with friction Employ Newton s Laws in 2D problems with circular motion Assignment: HW5, (Chapter 7, due 2/24, Wednesday) For Tuesday: Finish reading

### Dynamics Test K/U 28 T/I 16 C 26 A 30 Name: Dynamics Test K/U 28 T/I 16 C 26 A 30 A. True/False Indicate whether the sentence or statement is true or false. 1. The normal force that acts on an object is always equal in magnitude and opposite

### SPH3U1 - Dynamics Problems Set 3 SPH3U1 - Dynamics Problems Set 3 Problems 1. A force of 1.2 N [ ] is applied to an object of mass 1.5 kg. It accelerates at 0.50 m/s 2 [ ] along a surface. Determine the force of friction that is acting

### Part A Atwood Machines Please try this link: LAST NAME FIRST NAME DATE Assignment 2 Inclined Planes, Pulleys and Accelerating Fluids Problems 83, 108 & 109 (and some handouts) Part A Atwood Machines Please try this link: http://www.wiley.com/college/halliday/0470469080/simulations/sim20/sim20.html

### Newton s Laws and Free-Body Diagrams General Physics I Newton s Laws and Free-Body Diagrams In the next few sections, we will be exploring some of the most fundamental laws of our universe, laws that govern the relationship actions and motion. These laws are

### d. Determine the power output of the boy required to sustain this velocity. AP Physics C Dynamics Free Response Problems 1. A 45 kg boy stands on 30 kg platform suspended by a rope passing over a stationary pulley that is free to rotate. The other end of the rope is held by the

### A hockey puck slides on ice at constant velocity. What is the net force acting on the puck? A hockey puck slides on ice at constant velocity. What is the net force acting on the puck? A. Something more than its weight B. Equal to its weight C. Something less than its weight but more than zero

### Potential Energy & Conservation of Energy PHYS 101 Previous Exam Problems CHAPTER 8 Potential Energy & Conservation of Energy Potential energy Conservation of energy conservative forces Conservation of energy friction Conservation of energy external

### UNIT-07. Newton s Three Laws of Motion 1. Learning Objectives: UNIT-07 Newton s Three Laws of Motion 1. Understand the three laws of motion, their proper areas of applicability and especially the difference between the statements of the first

### 1. (P2.1A) The picture below shows a ball rolling along a table at 1 second time intervals. What is the object s average velocity after 6 seconds? PHYSICS FINAL EXAM REVIEW FIRST SEMESTER (01/2017) UNIT 1 Motion P2.1 A Calculate the average speed of an object using the change of position and elapsed time. P2.1B Represent the velocities for linear

### Choose the best answer for Questions 1-15 below. Mark your answer on your scantron form using a #2 pencil. Name: ID #: Section #: PART I: MULTIPLE CHOICE QUESTIONS Choose the best answer for Questions 1-15 below. Mark your answer on your scantron form using a #2 pencil. 1. A 55.0-kg box rests on a horizontal

### Phys101 Lecture 5 Dynamics: Newton s Laws of Motion Phys101 Lecture 5 Dynamics: Newton s Laws of Motion Key points: Newton s second law is a vector equation Action and reaction are acting on different objects Free-Body Diagrams Ref: 4-1,2,3,4,5,6,7. Page Physics 2A Chapter 4: Forces and Newton s Laws of Motion There is nothing either good or bad, but thinking makes it so. William Shakespeare It s not what happens to you that determines how far you will 1) Suppose that an object is moving with constant nonzero acceleration. Which of the following is an accurate statement concerning its motion? A) In equal times its speed changes by equal amounts. B) In