PHYS 100: Lecture 7. FRICTION and UNIFORM CIRCULAR MOTION. θ Mg. v R. R a. Static: Kinetic: Physics 100 Lecture 7, Slide 1
|
|
- Morgan Parrish
- 5 years ago
- Views:
Transcription
1 PHYS 100: Lecture 7 FICTION and UNIFO CICULA OTION v v θ a a θ g Static: Kinetic: f f µ S N = µ N K v a = Physics 100 Lecture 7, Slide 1
2 usic Who is the Artist? A) Pete Fountain B) Dr. ichael White C) Al Hirt D) George Lewis E) Dr. John Why?? FOU DAYS TO ADI GAS aster of traditional New Orleans jazz!! Catch the Traditional Jazz Orchestra (Jeff Helgesen et al) at the Iron Post from 5pm -7pm on Fat Tuesday! Physics 100 Lecture 7, Slide
3 idterm Exam Next FIDAY (ar 11): eview Lecture 57 Loomis Following Tuesday (10/19) idterm Exam 7pm in 136 Loomis any conflicts??? Physics 100 Lecture 7, Slide 3
4 WHAT DID YOU FIND DIFFICULT? eal forces in centripetal acceleration. Newton s Second Law : VEY IPOTANT DISTINCTION HEE. r a = r F m net Kinematics (description) Dynamics (cause) Newton s Second Law works in INETIAL FAES A otating Body is NOT an INETIAL FAE The only FOCES that should appear on a FEE BODY DIAGA are EAL FOCES As of now, you know about: weight, normal, tension, friction and applied EVEYTHINGGGGG!!!!!! Physics 100 Lecture 7, Slide 4
5 THE BIG IDEAS NOTE: THE BIG IDEAS AE ALWAYS GIVEN IN THE LAST SLIDE 1. Frictional forces oppose relative motion:. Static (use ΣF i = 0) & Kinetic (use f = µ K N) are different 3. Uniform circular motion has centripetal acceleration = v / Physics 100 Lecture 7, Slide 5
6 Direction of Frictional Forces Two ways to determine f BonA : A B Friction forces oppose relative motion (A relative to B) Draw freebody diagram and use Newton s Second Law A block of mass rests on the bed of a truck that is accelerating to the left a What is the direction of the frictional force that the bed of the truck exerts on the block? (A) To left (B) To right (C) f = 0 Physics 100 Lecture 7, Slide 6
7 Direction of Frictional Forces Suppose bed of truck were frictionless. What would be the motion of relative to the truck? a (A) Slide forward (B) Slide backward (C) emain at rest WHY?? Think of it from the reference frame of the ground (inertial) Are there any horizontal forces on? NO! The block would remain at rest relative to the ground (a = 0) Since truck moves to the left, would move to the right ELATIVE to thetuck NOTE: The Truck is NOT an INETIAL FAE Newton s Second Law is NOT TUE in TUCK FAE a 0 BUT F net = 0 Physics 100 Lecture 7, Slide 7
8 Direction of Frictional Forces Two ways to determine f BonA : A B Friction forces oppose relative motion (A relative to B) Draw freebody diagram and use Newton s Second Law A block of mass rests on the bed of a truck that is accelerating to the left a What is the direction of the frictional force that the bed of the truck exerts on the block? (A) To left (B) To right (C) f = 0 Since, in absence of friction, would slide back (to right), the friction force on must OPPOSE this motion and point forward (to left) We can get this result from Newton s Second Law ALSO. knowing that the acceleration is to the LEFT! f Truckon Physics 100 Lecture 7, Slide 8
9 Preflight 1 A constant force F is applied to block m and both blocks are observed to move together with constant acceleration. What is the frictional force f that m exerts on? (A) f < F : f points to left (C) f > F : f points to left (B) f < F : f points to right (D) f > F : f points to right You said: Since they both move to the right, then F has to be greater than f so that it is able to overcome friction and move. f points to the left because it has to oppose the motion of m. For starters, f must point to the right. If the frictional force was not great enough to allow the blocks to move together than would slide off m on the left side of the block. To counter that f points to the right to allow them to move together. Also, f does not have to be large than F because block has mass, and the force of g will contribute to the staying on the block m. f only has to be what it is to do the job it does A B C D Physics 100 Lecture 7, Slide 9
10 Preflight 1: Direction A constant force F is applied to block m and both blocks are observed to move together with constant acceleration. What is the frictional force f that m exerts on? (A) f < F : f points to left (C) f > F : f points to left (B) f < F : f points to right (D) f > F : f points to right Two ways In absence of friction, there would be NO horizontal force on Therefore would NOT accelerate, but m would ACCELEATE to IGHT Therefore, ELATIVE to m, would be moving to the LEFT. The force m exerts on then would OPPOSE this motion and point to the IGHT Free Body Diagram: f N g The acceleration of is to the right (as measured in INETIAL FAE) Newton s Second Law demands f to point to right since it is the ONLY horizontal force and must be the CAUSE of the acceleration of. Physics 100 Lecture 7, Slide 10
11 Preflight 1: agnitude A constant force F is applied to block m and both blocks are observed to move together with constant acceleration. What is the frictional force f that m exerts on? (A) f < F : f points to left (C) f > F : f points to left (B) f < F : f points to right (D) f > F : f points to right Free Body Diagrams: f m g N m NOTE the Action-eaction Pairs F r r F mon = F onm N m m mg N floorm We used this info to draw f m in the opposite direction to f m f m Free Body for m f m < F a > 0 (to right) F f = m ma Physics 100 Lecture 7, Slide 11
12 Follow Up Case I A constant force F is applied to block m in Case I and to block in Case II and in both cases, both blocks are observed to move together with constant acceleration. ( > m) F m Compare the magnitude of the force f that m exerts on. (A) f(i) < f(ii) (B) f(i) = f(ii) (C) f(i) > f(ii) F Case II m Free Body Diagrams Case I Free Body Diagrams Case II f m g N m F N m m f m mg N floorm N m F g f m N floor f m m mg N m Newton s Second Law > m f > I m f II m Newton s Second Law f I m = a NOTE: These are real friction forces (NOT ma forces). They simply have the value = ma. f II m = ma Physics 100 Lecture 7, Slide 1
13 Static Friction A block of mass rests on a horizontal floor. The coefficient of static friction between the block and the floor is equal to µ S. What is f, the frictional force that the floor exerts on? µ S (A) f = µ S g (B) 0 < f < µ S g (C) f=0 Free Body Diagram N g There is no force for the friction force to oppose!! f N g would accelerate!! Physics 100 Lecture 7, Slide 13
14 Static Friction A block of mass rests on an incline of angle θ, as shown. The coefficient of static friction between the block and the floor is equal to µ S. What is f, the frictional force that the plane exerts on? (A) f = µ S gcosθ (D) f = gcosθ (B) f = µ S gsinθ (E) f = gsinθ (C) f=0 θ µ S Free Body Diagram Perpendicular to the plane: N g cos θ = 0 N θ φ g f Parallel to the plane: f g cos φ = 0 f = g cosφ φ = 90 θ f = g sinθ Physics 100 Lecture 7, Slide 14
15 Preflight 3 In both cases a block of mass m is at rest on the surface which has a coefficient of static friction µ S. Compare f I to f II, the frictional forces on the blocks in I & II (A) f I < f II (B) f I = f II (C) f I > f II You said: Case one has no static friction added so case II would have a greater frictional force The force of friction would be the same because the block has the same mass. The frictional force depends on the Normal Force. The Normal force = mg in Case I, but it only equals gcos(theta) in case II. Therefore, the frictional force of Case I is greater than Case II f I is ZEO!! A B C Physics 100 Lecture 7, Slide 15
16 Uniform Circular otion KINEATICS ONLY!! OTION HAS BEEN SPECIFIED r a r dv dt a v = This is TUE whenever you have uniform circular motion, no matter what kind of force causes it!! A block of mass rests on a turntable. The turntable makes one complete revolution in P seconds. Two pennies are at rest relative to the turntable and are located at distances and from the center, We want to determine the accelerations of the pennies. First step: What is the speed of the penny at? (A) v = P (B) v = πp (C) v = P (D) π v = P Distance = π Time = P P is called the PEIOD Physics 100 Lecture 7, Slide 16
17 Uniform Circular otion A block of mass rests on a turntable. The turntable makes one complete revolution in P seconds. Two pennies are at rest relative to the turntable and are located at distances and from the center. Compare the accelerations of the pennies at and. (A) a ( ) = 1 4 a() a = (C) a ( ) = a() (B) ( ) 1 a() a = (E) a ( ) = 4a() (D) ( ) a() v π P = at Acceleration at : Acceleration at : a v = a 1 4π 4 = ( ) = π P P π () v = a 1 16π 8 = ( ) = π P P P a = 1 a General: a = ω ω is Angular Velocity (radians/sec): ω v Physics 100 Lecture 7, Slide 17
18 Uniform Circular otion A block of mass rests on a turntable. The turntable makes one complete revolution in P seconds. Two pennies are at rest relative to the turntable and are located at distances and from the center. Compare the net forces on the pennies at and. (A) F ( ) = 1 4 F() F = (C) F ( ) = F() (B) ( ) 1 F() F = (E) F ( ) = 4F() (D) ( ) F() at : π v = P ω v a = ω π = P F net = ma a = ω F net = mω WHAT IS THIS FOCE?? FICTION!! f g N side view Here: f = mω It must also be true that: f µ Sg Physics 100 Lecture 7, Slide 18
19 DEO ω Friction force responsible for penny s acceleration Friction force is proportional to the distance from the center f = mω (A) As I increase the angular velocity, what will happen? Both pennies fly off at same time (C) (B) Penny at flies off first Penny at flies off first at : π v = P ω v a = ω π = P WHY!! As ω increases, the frictional force must increase (to provide increased acceleration) f f = mω There is, however, a maximum possible frictional force: f = µ g S max g N The force at is always bigger than the force at The force at will reach maximum before the force at Physics 100 Lecture 7, Slide 19
20 Preflight 5 ass m is connected to a string and moves with speed v in uniform circular motion of radius in horizontal plane. The tension in the string is T. If we double the radius ( = ), but keep the period of the motion the same, how is T related to T? (A) T = ¼ T (B) T = 1/ T (C) T = T You said: (D) T = T (E) T = 4T T=(V^)/, so if you double the radius, the equation will be multiplied by 1/. If you double the adius you have to double the speed to keep the period the same. Since the Tension force in this case is mv^/, doubling the radius and velocity would result in a net change of to the original Tension. to double the radius and keep the period the same, the ball will now travel twice as far in the same time interval. this will press the need for a greater velocity (v to v). in equations in relation to kinematics, the velocity is a squared term. thus, if he transition from v to v, our force to hold this will go from T to 4T ( squared is four). π v = P a v = T = ma KEY A B C D E v doubles when doubles a doubles when doubles T doubles when doubles Physics 100 Lecture 7, Slide 0
PHYS 100: Lecture 7. FRICTION and UNIFORM CIRCULAR MOTION. θ Mg. v R. R a. Static: Kinetic: Physics 100 Lecture 7, Slide 1
PHYS 100: Lecture 7 FICTION and UNIFO CICULA OTION θ a a θ g Static: Kinetic: f f µ S N µ N K a Physics 100 Lecture 7, Slide 1 usic Who is the Artist? A) Professor Longhair B) John Cleary C) Allen Toussaint
More informationMusic. Who is the Artist? A) The Meters B) The Neville Brothers C) Trombone Shorty D) Michael Franti E) Radiators
PHYS 100: Lecture 6 NEWTON S FIRST and THIRD LAWS First Law: An object subject to no external forces is at rest or moves with constant velocity if viewed from an inertial reference frame. Third law: For
More informationMusic. Who is the Artist? A) Oscar Peterson B) Kenny Barron C) Dave Brubeck D) Thelonius Monk E) Marcus Roberts
PHYS 100: Lecture 6 NEWTON S FIRST and THIRD LAWS First Law: An object subject to no external forces is at rest or moves with constant velocity if viewed from an inertial reference frame. Third law: For
More informationFriction 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:
More informationCircular 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
More informationAssignment 9. to roll without slipping, how large must F be? Ans: F = R d mgsinθ.
Assignment 9 1. A heavy cylindrical container is being rolled up an incline as shown, by applying a force parallel to the incline. The static friction coefficient is µ s. The cylinder has radius R, mass
More informationdt 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
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 informationUniform Circular Motion
Slide 1 / 112 Uniform Circular Motion 2009 by Goodman & Zavorotniy Slide 2 / 112 Topics of Uniform Circular Motion (UCM) Kinematics of UCM Click on the topic to go to that section Period, Frequency, and
More informationChapter 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.
More informationCircular Motion. A car is traveling around a curve at a steady 45 mph. Is the car accelerating? A. Yes B. No
Circular Motion A car is traveling around a curve at a steady 45 mph. Is the car accelerating? A. Yes B. No Circular Motion A car is traveling around a curve at a steady 45 mph. Which vector shows the
More information1 A car moves around a circular path of a constant radius at a constant speed. Which of the following statements is true?
Slide 1 / 30 1 car moves around a circular path of a constant radius at a constant speed. Which of the following statements is true? The car s velocity is constant The car s acceleration is constant The
More informationForces Part 1: Newton s Laws
Forces Part 1: Newton s Laws Last modified: 13/12/2017 Forces Introduction Inertia & Newton s First Law Mass & Momentum Change in Momentum & Force Newton s Second Law Example 1 Newton s Third Law Common
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 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 informationPROBLEM 2 10 points. [ ] increases [ ] decreases [ ] stays the same. Briefly justify your answer:
PROBLEM 2 10 points A disk of mass m is tied to a block of mass 2m via a string that passes through a hole at the center of a rotating turntable. The disk rotates with the turntable at a distance R from
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 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
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 informationDynamics: Forces. Lecture 7. Chapter 5. Course website:
Lecture 7 Chapter 5 Dynamics: Forces Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsi Today we are going to discuss: Chapter 5: Some leftovers from rotational motion Ch.4 Force,
More informationReview for 3 rd Midterm
Review for 3 rd Midterm Midterm is on 4/19 at 7:30pm in the same rooms as before You are allowed one double sided sheet of paper with any handwritten notes you like. The moment-of-inertia about the center-of-mass
More informationApplying 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
More informationSection /07/2013. PHY131H1F University of Toronto Class 9 Preclass Video by Jason Harlow. Based on Knight 3 rd edition Ch. 5, pgs.
PHY131H1F University of Toronto Class 9 Preclass Video by Jason Harlow Based on Knight 3 rd edition Ch. 5, pgs. 116-133 Section 5.1 A force is a push or a pull What is a force? What is a force? A force
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 informationMASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8.01 Physics Fall Term Exam 2 Solutions
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 801 Physics Fall Term 013 Problem 1 of 4 (5 points) Exam Solutions Answers without work shown will not be given any credit A block of mass m
More informationPhysics for Scientists and Engineers. Chapter 5 Force and Motion
Physics for Scientists and Engineers Chapter 5 Force and Motion Spring, 2008 Ho Jung Paik Force Forces are what cause any change in the velocity of an object The net force is the vector sum of all the
More informationForce 10/01/2010. (Weight) MIDTERM on 10/06/10 7:15 to 9:15 pm Bentley 236. (Tension)
Force 10/01/2010 = = Friction Force (Weight) (Tension), coefficient of static and kinetic friction MIDTERM on 10/06/10 7:15 to 9:15 pm Bentley 236 2008 midterm posted for practice. Help sessions Mo, Tu
More informationPhysics 111: Mechanics Lecture 9
Physics 111: Mechanics Lecture 9 Bin Chen NJIT Physics Department Circular Motion q 3.4 Motion in a Circle q 5.4 Dynamics of Circular Motion If it weren t for the spinning, all the galaxies would collapse
More information2. F = ma. Newton s Laws. 1. Bodies stay at constant velocity unless acted on by outside force!
Newton s Laws review 1. Bodies stay at constant velocity unless acted on by outside force! Defines mass, m, as 2. F ma all that act on the body parameter reflecting body s resistance to motion 3. Action
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 informationPHYS 100: Lecture 11
PHYS 00: Lecture UNIVSAL GAVITATION and SPINGS F S x 0 F S x F x F F S = G S F = -k(x x 0 ) PHYS 00 Lecture, Slide usic Who are the Artists? A) Whitney Houston and Tina Turner B) Nina Simone and Patti
More informationLecture 6. Circular Motion. Pre-reading: KJF 6.1 and 6.2. Please take a clicker CIRCULAR MOTION KJF
Lecture 6 Circular Motion Pre-reading: KJF 6.1 and 6.2 Please take a clicker CIRCULAR MOTION KJF 6.1 6.4 Angular position If an object moves in a circle of radius r, then after travelling a distance s
More informationPHYSICS 221, FALL 2009 EXAM #1 SOLUTIONS WEDNESDAY, SEPTEMBER 30, 2009
PHYSICS 221, FALL 2009 EXAM #1 SOLUTIONS WEDNESDAY, SEPTEMBER 30, 2009 Note: The unit vectors in the +x, +y, and +z directions of a right-handed Cartesian coordinate system are î, ĵ, and ˆk, respectively.
More informationPhysics 101: Lecture 08. Common Incorrect Forces (Spooky Rules!) Items below are NOT forces Acceleration: F Net = ma Centripetal Acceleration
Physics 101: Lecture 08 Circular Motion Review of Newton s Laws Checkpoint 4, Lecture 7 In the game of tetherball, a rope connects a ball to the top of a vertical pole as shown. In one case, a ball of
More informationPhysics A - PHY 2048C
Physics A - PHY 2048C Mass & Weight, Force, and Friction 10/04/2017 My Office Hours: Thursday 2:00-3:00 PM 212 Keen Building Warm-up Questions 1 Did you read Chapters 6.1-6.6? 2 In your own words: What
More informationPhysics UCSB TR 2:00-3:15 lecture Final Exam Wednesday 3/17/2010
Physics @ UCSB TR :00-3:5 lecture Final Eam Wednesday 3/7/00 Print your last name: Print your first name: Print your perm no.: INSTRUCTIONS: DO NOT START THE EXAM until you are given instructions to do
More informationPHYSICS. Chapter 5 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 5 Lecture RANDALL D. KNIGHT Chapter 5 Force and Motion IN THIS CHAPTER, you will learn about the connection between force and motion.
More informationFriction forces. Lecture 8. Chapter 6. Physics I. Course website:
Lecture 8 Physics I Chapter 6 Friction forces Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsi Today we are going to discuss: Chapter 6: Some leftover (Ch.5) Kinetic/Static Friction:
More informationDEVIL PHYSICS THE BADDEST CLASS ON CAMPUS AP PHYSICS
DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS AP PHYSICS GIANCOLI CHAPTER 5: CIRCULAR MOTION; GRAVITATION LSN 5-1: KINEMATICS OF UNIFORM CIRCULAR MOTION LSN 5-2: DYNAMICS OF UNIFORM CIRCULAR MOTION LSN 5-3:
More informationChapter 4 Dynamics: Newton s Laws of Motion
Chapter 4 Dynamics: Newton s Laws of Motion 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 Force Applications
More informationPhysics 207: Lecture 24. Announcements. No labs next week, May 2 5 Exam 3 review session: Wed, May 4 from 8:00 9:30 pm; here.
Physics 07: Lecture 4 Announcements No labs next week, May 5 Exam 3 review session: Wed, May 4 from 8:00 9:30 pm; here Today s Agenda ecap: otational dynamics and torque Work and energy with example Many
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 informationAnnouncements 15 Oct 2013
Announcements 15 Oct 2013 1. While you re waiting for class to start, see how many of these blanks you can fill out. Tangential Accel.: Direction: Causes speed to Causes angular speed to Therefore, causes:
More informationMULTIPLE 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
More informationExam 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
More informationMULTIPLE 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.
More informationDynamics: Forces and Newton s Laws of Motion
Lecture 7 Chapter 5 Dynamics: Forces and Newton s Laws of Motion Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsi Today we are going to discuss: Chapter 5: Force, Mass: Section 5.1
More informationNormal Force. W = mg cos(θ) Normal force F N = mg cos(θ) F N
Normal Force W = mg cos(θ) Normal force F N = mg cos(θ) Note there is no weight force parallel/down the include. The car is not pressing on anything causing a force in that direction. If there were a person
More informationLecture 7. Forces: Newton s Laws. Problem-Solving Tactics: Friction and Centripetal Motion. Physics 105; Summer How do we jump?
ecture 7 Problem-Solving Tactics: Friction and Centripetal Motion (H&W, Chapters 5-6) http://web.njit.edu/~sirenko/ Newton s aws I. If no net force acts on a body, then the body s velocity cannot change.
More informationTuesday February 7. Topics for this Lecture: Forces: Friction on Planes, Tension With Pulleys
Tuesday February 7 Topics for this Lecture: Forces: Friction on Planes, Tension With Pulleys Write these equations in your notes if they re not already there. You will want them for Exam 1 & the Final.
More informationLecture 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
More informationAP Physics I Summer Work
AP Physics I Summer Work 2018 (20 points) Please complete the following set of questions and word problems. Answers will be reviewed in depth during the first week of class followed by an assessment based
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 informationPH1104/PH114S MECHANICS
PH04/PH4S MECHANICS SEMESTER I EXAMINATION 06-07 SOLUTION MULTIPLE-CHOICE QUESTIONS. (B) For freely falling bodies, the equation v = gh holds. v is proportional to h, therefore v v = h h = h h =.. (B).5i
More informationMultiple Choice (A) (B) (C) (D)
Multiple Choice 1. A ball is fastened to a string and is swung in a vertical circle. When the ball is at the highest point of the circle its velocity and acceleration directions are: (A) (B) (C) (D) 2.
More informationWork and kinetic Energy
Work and kinetic Energy Problem 66. M=4.5kg r = 0.05m I = 0.003kgm 2 Q: What is the velocity of mass m after it dropped a distance h? (No friction) h m=0.6kg mg Work and kinetic Energy Problem 66. M=4.5kg
More informationPHYS 100: Lecture 5. F F ma NEWTON S SECOND LAW. N Mg. Physics 100 Lecture 5, Slide 1
PHYS 100: Lecture 5 NEWTON S SECOND LAW T v N u ma tot i θ Physics 100 Lecture 5, Slide 1 usic Who is the Artist? A) David Benoit B) Oscar Peterson C) Thelonius onk D) Dr. John E) ose Allison classics
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 informationPSI AP Physics B Circular Motion
PSI AP Physics B Circular Motion Multiple Choice 1. A ball is fastened to a string and is swung in a vertical circle. When the ball is at the highest point of the circle its velocity and acceleration directions
More informationFirst-Year Engineering Program. Physics RC Reading Module
Physics RC Reading Module Frictional Force: A Contact Force Friction is caused by the microscopic interactions between the two surfaces. Direction is parallel to the contact surfaces and proportional to
More information= v 0 x. / t = 1.75m / s 2.25s = 0.778m / s 2 nd law taking left as positive. net. F x ! F
Multiple choice Problem 1 A 5.-N bos sliding on a rough horizontal floor, and the only horizontal force acting on it is friction. You observe that at one instant the bos sliding to the right at 1.75 m/s
More informationy(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
More information( m/s) 2 4(4.9 m/s 2 )( 52.7 m)
Version 072 idterm 2 OConnor (05141) 1 This print-out should have 18 questions ultiple-choice questions may continue on the next column or page find all choices before answering V1:1, V2:1, V3:3, V4:5,
More information( m/s) 2 4(4.9 m/s 2 )( 53.2 m)
Version 074 idterm 2 OConnor (05141) 1 This print-out should have 18 questions ultiple-choice questions may continue on the next column or page find all choices before answering V1:1, V2:1, V3:3, V4:5,
More informationEnd-of-Chapter Exercises
End-of-Chapter Exercises Exercises 1 12 are conceptual questions that are designed to see if you have understood the main concepts of the chapter. 1. Figure 11.21 shows four different cases involving a
More information1. 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.
More information16. Rotational Dynamics
6. Rotational Dynamics A Overview In this unit we will address examples that combine both translational and rotational motion. We will find that we will need both Newton s second law and the rotational
More informationChapter 5. The Laws of Motion
Chapter 5 The Laws of Motion Sir Isaac Newton 1642 1727 Formulated basic laws of mechanics Discovered Law of Universal Gravitation Invented form of calculus Many observations dealing with light and optics
More informationChapter 5. The Laws of Motion
Chapter 5 The Laws of Motion The Laws of Motion The description of an object in There was no consideration of what might influence that motion. Two main factors need to be addressed to answer questions
More informationPhysics 2514 Lecture 13
Physics 2514 Lecture 13 P. Gutierrez Department of Physics & Astronomy University of Oklahoma Physics 2514 p. 1/18 Goals We will discuss some examples that involve equilibrium. We then move on to a discussion
More informationExam #2, Chapters 5-7 PHYS 101-4M MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Exam #2, Chapters 5-7 Name PHYS 101-4M MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The quantity 1/2 mv2 is A) the potential energy of the object.
More informationMASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics Physics 8.01T Fall Term 2004
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics Physics 8.0T Fall Term 2004 Problem Set 3: Newton's Laws of Motion, Motion: Force, Mass, and Acceleration, Vectors in Physics Solutions Problem
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 informationTue Sept 15. Dynamics - Newton s Laws of Motion. Forces: Identifying Forces Free-body diagram Affect on Motion
Tue Sept 15 Assignment 4 Friday Pre-class Thursday Lab - Print, do pre-lab Closed toed shoes Exam Monday Oct 5 7:15-9:15 PM email me if class conflict or extended time Dynamics - Newton s Laws of Motion
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 information11-2 A General Method, and Rolling without Slipping
11-2 A General Method, and Rolling without Slipping Let s begin by summarizing a general method for analyzing situations involving Newton s Second Law for Rotation, such as the situation in Exploration
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 informationLAWS OF MOTION Newtons laws of motion. (i) First law: Law of inertia. Every body continues to be in its state of rest or of uniform motion in a
LAWS OF MOTION Newtons laws of motion. (i) First law: Law of inertia. Every body continues to be in its state of rest or of uniform motion in a straight line unless compelled to change that state by an
More informationContents. Objectives IAI motion w/o force motion with force F=ma third law work and energy circular motion Final Exam mechanics questions Recap IAI
Physics 121 for Majors Section 1 IAI Review 4 Review for IAI and Final Exam Exam Details In the Testing Center Friday - Wednesday Wed. is a late day with a $5 fee Hours: 8 am 9 pm Friday 10 am 3 pm Saturday
More informationWelcome back to Physics 211
Welcome back to Physics 211 Today s agenda: Circular motion Impulse and momentum 08-2 1 Current assignments Reading: Chapter 9 in textbook Prelecture due next Thursday HW#8 due NEXT Friday (extension!)
More informationToday. What concepts did you find most difficult, or what would you like to be sure we discuss in lecture? EXAM 1. Friction (two types)
Physics 101: Lecture 07 Frictional forces and circular motion What concepts did you find most difficult, or what would you like to be sure we discuss in lecture? i get confused as to which way the friction
More informationPhysics Exam 2 October 11, 2007
INSTRUCTIONS: Write your NAME on the front of the blue exam booklet. The exam is closed book, and you may have only pens/pencils and a calculator (no stored equations or programs and no graphing). Show
More informationPHYSICS 221, FALL 2010 EXAM #1 Solutions WEDNESDAY, SEPTEMBER 29, 2010
PHYSICS 1, FALL 010 EXAM 1 Solutions WEDNESDAY, SEPTEMBER 9, 010 Note: The unit vectors in the +x, +y, and +z directions of a right-handed Cartesian coordinate system are î, ĵ, and ˆk, respectively. In
More informationExperiment #7 Centripetal Force Pre-lab Questions Hints
Experiment #7 Centripetal Force Pre-lab Questions Hints The following are some hints for this pre-lab, since a few of these questions can be a little difficult. Note that these are not necessarily the
More informationLecture 2 - Force Analysis
Lecture 2 - orce Analysis A Puzzle... Triangle or quadrilateral? 4 distinct points in a plane can either be arrange as a triangle with a point inside or as a quadrilateral. Extra Brownie Points: Use the
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 informationNewton 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
More informationPhysics 201, Lecture 10
Physics 201, Lecture 10 Today s Topics n Circular Motion and Newton s Law (Sect. 6.1,6.2) n Centripetal Force in Uniform Circular Motion n Examples n n Motion in Accelerated Frame (sec. 6.3, conceptual
More informationPhys 270 Final Exam. Figure 1: Question 1
Phys 270 Final Exam Time limit: 120 minutes Each question worths 10 points. Constants: g = 9.8m/s 2, G = 6.67 10 11 Nm 2 kg 2. 1. (a) Figure 1 shows an object with moment of inertia I and mass m oscillating
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 8 Wednesday, October 14, 2015
Physics 8 Wednesday, October 14, 2015 HW5 due Friday (problems from Ch9 and Ch10.) Bill/Camilla switch HW sessions this week only (same rooms, same times what changes is which one of us is there): Weds
More informationApplying 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 Goals for Chapter 5 To use and apply Newton s Laws
More informationChapter 8 Lecture Notes
Chapter 8 Lecture Notes Physics 2414 - Strauss Formulas: v = l / t = r θ / t = rω a T = v / t = r ω / t =rα a C = v 2 /r = ω 2 r ω = ω 0 + αt θ = ω 0 t +(1/2)αt 2 θ = (1/2)(ω 0 +ω)t ω 2 = ω 0 2 +2αθ τ
More informationRotational Kinematics and Dynamics. UCVTS AIT Physics
Rotational Kinematics and Dynamics UCVTS AIT Physics Angular Position Axis of rotation is the center of the disc Choose a fixed reference line Point P is at a fixed distance r from the origin Angular Position,
More informationPHYS 100 (from 221) Newton s Laws Week8. Exploring the Meaning of Equations
Exploring the Meaning of Equations Exploring the meaning of the relevant ideas and equations introduced recently. This week we ll focus mostly on Newton s second and third laws: Kinematics describes the
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 informationPhys101 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
More informationChapter 4. Forces and Newton s Laws of Motion. F=ma; gravity
Chapter 4 Forces and Newton s Laws of Motion F=ma; gravity 0) Background Galileo inertia (horizontal motion) constant acceleration (vertical motion) Descartes & Huygens Conservation of momentum: mass x
More informationChapter 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.
More informationChapter 4 Newton s Laws. September 24 and September 29, 2009
Chapter 4 Newton s Laws September 24 and September 29, 2009 First exam for Physics 201: Tuesday, September 29, 2009 5:45 7:00 Bascom 272 Review sessions: Saturday 9/26, 10am-12pm, 2241 Chamberlin (Jialu)
More information