Formulations of Classical Mechanics . Introduction
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Glossary Physics (I-Introduction)
1 Glossary Physics (I-introduction) - Efficiency: The percent of the work put into a machine that is converted into useful work output; = work done / energy used [-]. = eta In machines: The work output of any machine cannot exceed the work input (<=100%); in an ideal machine, where no energy is transformed into heat: work(input) = work(output), =100%. Energy: The property of a system that enables it to do work. Conservation o. E.: Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes. Equilibrium: The state of an object when not acted upon by a net force or net torque; an object in equilibrium may be at rest or moving at uniform velocity - not accelerating. Mechanical E.: The state of an object or system of objects for which any impressed forces cancels to zero and no acceleration occurs. Dynamic E.: Object is moving without experiencing acceleration. Static E.: Object is at rest.F Force: The influence that can cause an object to be accelerated or retarded; is always in the direction of the net force, hence a vector quantity; the four elementary forces are: Electromagnetic F.: Is an attraction or repulsion G, gravit. const.6.672E-11[Nm2/kg2] between electric charges: d, distance [m] 2 2 2 2 F = 1/(40) (q1q2/d ) [(CC/m )(Nm /C )] = [N] m,M, mass [kg] Gravitational F.: Is a mutual attraction between all masses: q, charge [As] [C] 2 2 2 2 F = GmM/d [Nm /kg kg 1/m ] = [N] 0, dielectric constant Strong F.: (nuclear force) Acts within the nuclei of atoms: 8.854E-12 [C2/Nm2] [F/m] 2 2 2 2 2 F = 1/(40) (e /d ) [(CC/m )(Nm /C )] = [N] , 3.14 [-] Weak F.: Manifests itself in special reactions among elementary e, 1.60210 E-19 [As] [C] particles, such as the reaction that occur in radioactive decay. -
A Brief History and Philosophy of Mechanics
A Brief History and Philosophy of Mechanics S. A. Gadsden McMaster University, [email protected] 1. Introduction During this period, several clever inventions were created. Some of these were Archimedes screw, Hero of Mechanics is a branch of physics that deals with the Alexandria’s aeolipile (steam engine), the catapult and interaction of forces on a physical body and its trebuchet, the crossbow, pulley systems, odometer, environment. Many scholars consider the field to be a clockwork, and a rolling-element bearing (used in precursor to modern physics. The laws of mechanics Roman ships). [5] Although mechanical inventions apply to many different microscopic and macroscopic were being made at an accelerated rate, it wasn’t until objects—ranging from the motion of electrons to the after the Middle Ages when classical mechanics orbital patterns of galaxies. [1] developed. Attempting to understand the underlying principles of 3. Classical Period (1500 – 1900 AD) the universe is certainly a daunting task. It is therefore no surprise that the development of ‘idea and thought’ Classical mechanics had many contributors, although took many centuries, and bordered many different the most notable ones were Galileo, Huygens, Kepler, fields—atomism, metaphysics, religion, mathematics, Descartes and Newton. “They showed that objects and mechanics. The history of mechanics can be move according to certain rules, and these rules were divided into three main periods: antiquity, classical, and stated in the forms of laws of motion.” [1] quantum. The most famous of these laws were Newton’s Laws of 2. Period of Antiquity (800 BC – 500 AD) Motion, which accurately describe the relationships between force, velocity, and acceleration on a body. -
Classical Mechanics
Classical Mechanics Hyoungsoon Choi Spring, 2014 Contents 1 Introduction4 1.1 Kinematics and Kinetics . .5 1.2 Kinematics: Watching Wallace and Gromit ............6 1.3 Inertia and Inertial Frame . .8 2 Newton's Laws of Motion 10 2.1 The First Law: The Law of Inertia . 10 2.2 The Second Law: The Equation of Motion . 11 2.3 The Third Law: The Law of Action and Reaction . 12 3 Laws of Conservation 14 3.1 Conservation of Momentum . 14 3.2 Conservation of Angular Momentum . 15 3.3 Conservation of Energy . 17 3.3.1 Kinetic energy . 17 3.3.2 Potential energy . 18 3.3.3 Mechanical energy conservation . 19 4 Solving Equation of Motions 20 4.1 Force-Free Motion . 21 4.2 Constant Force Motion . 22 4.2.1 Constant force motion in one dimension . 22 4.2.2 Constant force motion in two dimensions . 23 4.3 Varying Force Motion . 25 4.3.1 Drag force . 25 4.3.2 Harmonic oscillator . 29 5 Lagrangian Mechanics 30 5.1 Configuration Space . 30 5.2 Lagrangian Equations of Motion . 32 5.3 Generalized Coordinates . 34 5.4 Lagrangian Mechanics . 36 5.5 D'Alembert's Principle . 37 5.6 Conjugate Variables . 39 1 CONTENTS 2 6 Hamiltonian Mechanics 40 6.1 Legendre Transformation: From Lagrangian to Hamiltonian . 40 6.2 Hamilton's Equations . 41 6.3 Configuration Space and Phase Space . 43 6.4 Hamiltonian and Energy . 45 7 Central Force Motion 47 7.1 Conservation Laws in Central Force Field . 47 7.2 The Path Equation . -
Foundations of Newtonian Dynamics: an Axiomatic Approach For
Foundations of Newtonian Dynamics: 1 An Axiomatic Approach for the Thinking Student C. J. Papachristou 2 Department of Physical Sciences, Hellenic Naval Academy, Piraeus 18539, Greece Abstract. Despite its apparent simplicity, Newtonian mechanics contains conceptual subtleties that may cause some confusion to the deep-thinking student. These subtle- ties concern fundamental issues such as, e.g., the number of independent laws needed to formulate the theory, or, the distinction between genuine physical laws and deriva- tive theorems. This article attempts to clarify these issues for the benefit of the stu- dent by revisiting the foundations of Newtonian dynamics and by proposing a rigor- ous axiomatic approach to the subject. This theoretical scheme is built upon two fun- damental postulates, namely, conservation of momentum and superposition property for interactions. Newton’s laws, as well as all familiar theorems of mechanics, are shown to follow from these basic principles. 1. Introduction Teaching introductory mechanics can be a major challenge, especially in a class of students that are not willing to take anything for granted! The problem is that, even some of the most prestigious textbooks on the subject may leave the student with some degree of confusion, which manifests itself in questions like the following: • Is the law of inertia (Newton’s first law) a law of motion (of free bodies) or is it a statement of existence (of inertial reference frames)? • Are the first two of Newton’s laws independent of each other? It appears that -
Engineering Physics I Syllabus COURSE IDENTIFICATION Course
Engineering Physics I Syllabus COURSE IDENTIFICATION Course Prefix/Number PHYS 104 Course Title Engineering Physics I Division Applied Science Division Program Physics Credit Hours 4 credit hours Revision Date Fall 2010 Assessment Goal per Outcome(s) 70% INSTRUCTION CLASSIFICATION Academic COURSE DESCRIPTION This course is the first semester of a calculus-based physics course primarily intended for engineering and science majors. Course work includes studying forces and motion, and the properties of matter and heat. Topics will include motion in one, two, and three dimensions, mechanical equilibrium, momentum, energy, rotational motion and dynamics, periodic motion, and conservation laws. The laboratory (taken concurrently) presents exercises that are designed to reinforce the concepts presented and discussed during the lectures. PREREQUISITES AND/OR CO-RECQUISITES MATH 150 Analytic Geometry and Calculus I The engineering student should also be proficient in algebra and trigonometry. Concurrent with Phys. 140 Engineering Physics I Laboratory COURSE TEXT *The official list of textbooks and materials for this course are found on Inside NC. • COLLEGE PHYSICS, 2nd Ed. By Giambattista, Richardson, and Richardson, McGraw-Hill, 2007. • Additionally, the student must have a scientific calculator with trigonometric functions. COURSE OUTCOMES • To understand and be able to apply the principles of classical Newtonian mechanics. • To effectively communicate classical mechanics concepts and solutions to problems, both in written English and through mathematics. • To be able to apply critical thinking and problem solving skills in the application of classical mechanics. To demonstrate successfully accomplishing the course outcomes, the student should be able to: 1) Demonstrate knowledge of physical concepts by their application in problem solving. -
Exercises in Classical Mechanics 1 Moments of Inertia 2 Half-Cylinder
Exercises in Classical Mechanics CUNY GC, Prof. D. Garanin No.1 Solution ||||||||||||||||||||||||||||||||||||||||| 1 Moments of inertia (5 points) Calculate tensors of inertia with respect to the principal axes of the following bodies: a) Hollow sphere of mass M and radius R: b) Cone of the height h and radius of the base R; both with respect to the apex and to the center of mass. c) Body of a box shape with sides a; b; and c: Solution: a) By symmetry for the sphere I®¯ = I±®¯: (1) One can ¯nd I easily noticing that for the hollow sphere is 1 1 X ³ ´ I = (I + I + I ) = m y2 + z2 + z2 + x2 + x2 + y2 3 xx yy zz 3 i i i i i i i i 2 X 2 X 2 = m r2 = R2 m = MR2: (2) 3 i i 3 i 3 i i b) and c): Standard solutions 2 Half-cylinder ϕ (10 points) Consider a half-cylinder of mass M and radius R on a horizontal plane. a) Find the position of its center of mass (CM) and the moment of inertia with respect to CM. b) Write down the Lagrange function in terms of the angle ' (see Fig.) c) Find the frequency of cylinder's oscillations in the linear regime, ' ¿ 1. Solution: (a) First we ¯nd the distance a between the CM and the geometrical center of the cylinder. With σ being the density for the cross-sectional surface, so that ¼R2 M = σ ; (3) 2 1 one obtains Z Z 2 2σ R p σ R q a = dx x R2 ¡ x2 = dy R2 ¡ y M 0 M 0 ¯ 2 ³ ´3=2¯R σ 2 2 ¯ σ 2 3 4 = ¡ R ¡ y ¯ = R = R: (4) M 3 0 M 3 3¼ The moment of inertia of the half-cylinder with respect to the geometrical center is the same as that of the cylinder, 1 I0 = MR2: (5) 2 The moment of inertia with respect to the CM I can be found from the relation I0 = I + Ma2 (6) that yields " µ ¶ # " # 1 4 2 1 32 I = I0 ¡ Ma2 = MR2 ¡ = MR2 1 ¡ ' 0:3199MR2: (7) 2 3¼ 2 (3¼)2 (b) The Lagrange function L is given by L('; '_ ) = T ('; '_ ) ¡ U('): (8) The potential energy U of the half-cylinder is due to the elevation of its CM resulting from the deviation of ' from zero. -
Euler and the Dynamics of Rigid Bodies Sebastià Xambó Descamps
Euler and the dynamics of rigid bodies Sebastià Xambó Descamps Abstract. After presenting in contemporary terms an outline of the kinematics and dynamics of systems of particles, with emphasis in the kinematics and dynamics of rigid bodies, we will consider briefly the main points of the historical unfolding that produced this understanding and, in particular, the decisive role played by Euler. In our presentation the main role is not played by inertial (or Galilean) observers, but rather by observers that are allowed to move in an arbitrary (smooth, non-relativistic) way. 0. Notations and conventions The material in sections 0-6 of this paper is an adaptation of parts of the Mechanics chapter of XAMBÓ-2007. The mathematical language used is rather standard. The read- er will need a basic knowledge of linear algebra, of Euclidean geometry (see, for exam- ple, XAMBÓ-2001) and of basic calculus. 0.1. If we select an origin in Euclidean 3-space , each point can be specified by a vector , where is the Euclidean vector space associated with . This sets up a one-to-one correspondence between points and vectors . The inverse map is usually denoted . Usually we will speak of “the point ”, instead of “the point ”, implying that some point has been chosen as an origin. Only when conditions on this origin become re- levant will we be more specific. From now on, as it is fitting to a mechanics context, any origin considered will be called an observer. When points are assumed to be moving with time, their movement will be assumed to be smooth. -
Overview of the CALET Mission to the ISS 1 Introduction
32ND INTERNATIONAL COSMIC RAY CONFERENCE,BEIJING 2011 Overview of the CALET Mission to the ISS SHOJI TORII1,2 FOR THE CALET COLLABORATION 1Research Institute for Scinece and Engineering, Waseda University 2Space Environment Utilization Center, JAXA [email protected] DOI: 10.7529/ICRC2011/V06/0615 Abstract: The CALorimetric Electron Telescope (CALET) mission is being developed as a standard payload for the Exposure Facility of the Japanese Experiment Module (JEM/EF) on the International Space Station (ISS). The instrument consists of a segmented plastic scintillator charge measuring module, an imaging calorimeter consisting of 8 scintillating fiber planes with a total of 3 radiation lengths of tungsten plates interleaved with the fiber planes, and a total absorption calorimeter consisting of crossed PWO logs with a total depth of 27 radiation lengths. The major scientific objectives for CALET are to search for nearby cosmic ray sources and dark matter by carrying out a precise measurement of the electron spectrum (1 GeV - 20 TeV) and observing gamma rays (10 GeV - 10 TeV). CALET has a unique capability to observe electrons and gamma rays in the TeV region since the hadron rejection power is larger than 105 and the energy resolution better than 2 % above 100 GeV. CALET has also the capability to measure cosmic ray H, He and heavy nuclei up to 1000 TeV.∼ The instrument will also monitor solar activity and search for gamma ray transients. The phase B study has started, aimed at a launch in 2013 by H-II Transfer Vehicle (HTV) for a 5 year observation period on JEM/EF. -
Branched Hamiltonians and Supersymmetry
Branched Hamiltonians and Supersymmetry Thomas Curtright, University of Miami Wigner 111 seminar, 12 November 2013 Some examples of branched Hamiltonians are explored, as recently advo- cated by Shapere and Wilczek. These are actually cases of switchback poten- tials, albeit in momentum space, as previously analyzed for quasi-Hamiltonian dynamical systems in a classical context. A basic model, with a pair of Hamiltonian branches related by supersymmetry, is considered as an inter- esting illustration, and as stimulation. “It is quite possible ... we may discover that in nature the relation of past and future is so intimate ... that no simple representation of a present may exist.” – R P Feynman Based on work with Cosmas Zachos, Argonne National Laboratory Introduction to the problem In quantum mechanics H = p2 + V (x) (1) is neither more nor less difficult than H = x2 + V (p) (2) by reason of x, p duality, i.e. the Fourier transform: ψ (x) φ (p) ⎫ ⎧ x ⎪ ⎪ +i∂/∂p ⎪ ⇐⇒ ⎪ ⎬⎪ ⎨⎪ i∂/∂x p − ⎪ ⎪ ⎪ ⎪ ⎭⎪ ⎩⎪ This equivalence of (1) and (2) is manifest in the QMPS formalism, as initiated by Wigner (1932), 1 2ipy/ f (x, p)= dy x + y ρ x y e− π | | − 1 = dk p + k ρ p k e2ixk/ π | | − where x and p are on an equal footing, and where even more general H (x, p) can be considered. See CZ to follow, and other talks at this conference. Or even better, in addition to the excellent books cited at the conclusion of Professor Schleich’s talk yesterday morning, please see our new book on the subject ... Even in classical Hamiltonian mechanics, (1) and (2) are equivalent under a classical canonical transformation on phase space: (x, p) (p, x) ⇐⇒ − But upon transitioning to Lagrangian mechanics, the equivalence between the two theories becomes obscure. -
Chapter 11.Pdf
Chapter 11. Kinematics of Particles Contents Introduction Rectilinear Motion: Position, Velocity & Acceleration Determining the Motion of a Particle Sample Problem 11.2 Sample Problem 11.3 Uniform Rectilinear-Motion Uniformly Accelerated Rectilinear-Motion Motion of Several Particles: Relative Motion Sample Problem 11.5 Motion of Several Particles: Dependent Motion Sample Problem 11.7 Graphical Solutions Curvilinear Motion: Position, Velocity & Acceleration Derivatives of Vector Functions Rectangular Components of Velocity and Acceleration Sample Problem 11.10 Motion Relative to a Frame in Translation Sample Problem 11.14 Tangential and Normal Components Sample Problem 11.16 Radial and Transverse Components Sample Problem 11.18 Introduction Kinematic relationships are used to help us determine the trajectory of a snowboarder completing a jump, the orbital speed of a satellite, and accelerations during acrobatic flying. Dynamics includes: Kinematics: study of the geometry of motion. Relates displacement, velocity, acceleration, and time without reference to the cause of motion. Fdownforce Fdrive Fdrag Kinetics: study of the relations existing between the forces acting on a body, the mass of the body, and the motion of the body. Kinetics is used to predict the motion caused by given forces or to determine the forces required to produce a given motion. Particle kinetics includes : • Rectilinear motion: position, velocity, and acceleration of a particle as it moves along a straight line. • Curvilinear motion : position, velocity, and acceleration of a particle as it moves along a curved line in two or three dimensions. Rectilinear Motion: Position, Velocity & Acceleration • Rectilinear motion: particle moving along a straight line • Position coordinate: defined by positive or negative distance from a fixed origin on the line. -
Chapter 3 Motion in Two and Three Dimensions
Chapter 3 Motion in Two and Three Dimensions 3.1 The Important Stuff 3.1.1 Position In three dimensions, the location of a particle is specified by its location vector, r: r = xi + yj + zk (3.1) If during a time interval ∆t the position vector of the particle changes from r1 to r2, the displacement ∆r for that time interval is ∆r = r1 − r2 (3.2) = (x2 − x1)i +(y2 − y1)j +(z2 − z1)k (3.3) 3.1.2 Velocity If a particle moves through a displacement ∆r in a time interval ∆t then its average velocity for that interval is ∆r ∆x ∆y ∆z v = = i + j + k (3.4) ∆t ∆t ∆t ∆t As before, a more interesting quantity is the instantaneous velocity v, which is the limit of the average velocity when we shrink the time interval ∆t to zero. It is the time derivative of the position vector r: dr v = (3.5) dt d = (xi + yj + zk) (3.6) dt dx dy dz = i + j + k (3.7) dt dt dt can be written: v = vxi + vyj + vzk (3.8) 51 52 CHAPTER 3. MOTION IN TWO AND THREE DIMENSIONS where dx dy dz v = v = v = (3.9) x dt y dt z dt The instantaneous velocity v of a particle is always tangent to the path of the particle. 3.1.3 Acceleration If a particle’s velocity changes by ∆v in a time period ∆t, the average acceleration a for that period is ∆v ∆v ∆v ∆v a = = x i + y j + z k (3.10) ∆t ∆t ∆t ∆t but a much more interesting quantity is the result of shrinking the period ∆t to zero, which gives us the instantaneous acceleration, a. -
BRST APPROACH to HAMILTONIAN SYSTEMS Our Starting Point Is the Partition Function
BRST APPROACH TO HAMILTONIAN SYSTEMS A.K.Aringazin1, V.V.Arkhipov2, and A.S.Kudusov3 Department of Theoretical Physics Karaganda State University Karaganda 470074 Kazakstan Preprint KSU-DTP-10/96 Abstract BRST formulation of cohomological Hamiltonian mechanics is presented. In the path integral approach, we use the BRST gauge fixing procedure for the partition func- tion with trivial underlying Lagrangian to fix symplectic diffeomorphism invariance. Resulting Lagrangian is BRST and anti-BRST exact and the Liouvillian of classical mechanics is reproduced in the ghost-free sector. The theory can be thought of as a topological phase of Hamiltonian mechanics and is considered as one-dimensional cohomological field theory with the target space a symplectic manifold. Twisted (anti- )BRST symmetry is related to global N = 2 supersymmetry, which is identified with an exterior algebra. Landau-Ginzburg formulation of the associated d = 1, N = 2 model is presented and Slavnov identity is analyzed. We study deformations and per- turbations of the theory. Physical states of the theory and correlation functions of the BRST invariant observables are studied. This approach provides a powerful tool to investigate the properties of Hamiltonian systems. PACS number(s): 02.40.+m, 03.40.-t,03.65.Db, 11.10.Ef, 11.30.Pb. arXiv:hep-th/9811026v1 2 Nov 1998 [email protected] [email protected] [email protected] 1 1 INTRODUCTION Recently, path integral approach to classical mechanics has been developed by Gozzi, Reuter and Thacker in a series of papers[1]-[10]. They used a delta function constraint on phase space variables to satisfy Hamilton’s equation and a sort of Faddeev-Popov representation.