Unit 7 muscle mechanics

Start studying ISSA Unit 7: Muscle Mechanics. Learn vocabulary, terms, and more with flashcards, games, and other study tools actions and muscles play a major role and whether the exercise is effective and safe. This unit discusses muscle mechanics for the major joints and muscle groups that are involved in personal training. It looks at the musculoskeletal system with regard to joint action, joint makeup, muscle involvement, and the associated relationships between various muscle groups in the body

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  1. Unit 1: Unit 1 - Muscles Mechanics and Physiological Adaptations: Unit 2: Unit 2 - Nerves: Unit 3: Unit 3 - Neurological Adaptations: Unit 4: Unit 4 - Types of Tissue: Unit 5: Unit 5 - Muscle Tissue: Unit 6: Unit 6 - How Do Muscles Contract? Unit 7: Unit 7 - Types of Muscle Tissue: Unit 8: Unit 8 - Connective Tissues: Unit 9: Unit 8 - Levers.
  2. Muscle Mechanics Meredith Heller, Kristine Kocjan, Chris Steele, Jack Sinclair Math 392 The sarcomere is a basic unit of muscle function. It is made up of thick and thin laments We can also derive an equation for the force Pon the muscle: P= n 0 Z 1 1 p(x)u(x)dx (7) Where n 0 is the number of crossbridges in a half sarcomere and p(x).
  3. • Each muscle consists of a number of mixed motor units. • For a weak contraction of the whole muscle, only one or a few of its motor units are activated. • The number of muscle fibers per motor unit and the number of motor units per muscle vary widely, depending on the specific function of the muscle
  4. A skeletal muscle fiber is a long cylindrical, multinucleated cell that is filled with smaller units of filaments (Fig. 4.1). These STRUCTURE OF SKELETAL MUSCLE The functional unit that produces motion at a joint consists of two discrete units, the muscle belly and the tendon that binds the muscle belly to the bone. The structure of the mus

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  1. (3) The axon branches to supply a number of muscle fibers called a motor unit, and the action potential is conveyed to a motor end plate on each muscle fiber. (4) At the motor end plate, the action potential causes the release of packets or quanta of acetylcholine into the synaptic clefts on the surface of the muscle fiber
  2. Muscle mechanics outline • Types of muscle • Muscle anatomy • Function: macro, micro • Motor unit • Applications • Tissue engineering • Basic studies • Drug screening • Biobots • Other motile systems 1 Types of muscle: Skeletal (striated) and smooth muscle
  3. summaries overview of muscle structure explain or apply the general concept of modular design in the context of muscle structure. modular design: idea of iden

Muscle Mechanics Massage Therapy, Edmonton, Alberta. 364 likes · 14 were here. Offering a variety of massage modalities with highly trained RMT's to best serve you Skeletal muscle mechanics have been studied ever since people have shown an interest in human movement. However, our understanding of muscle contraction and muscle mechanical properties has changed fundamentally with the discovery of the sliding filament theory in 1954 and associated cross-bridge theory in 1957. Nevertheless, experimental evidence suggests that our knowledge of the mechanisms. Muscle Mechanics Zuheir A Hasan Professor of Physiology Department of basic medical sciences College of medicine HU 5/4/2021 1. Lecture objectives Skeletal Muscle Mechanics • Number of muscle fibers per motor unit • Number of muscle fibers available to contract (size of muscle Study Muscle Mechanics flashcards from Annette Liem's SUNY Upstate Medical University class online, or in Brainscape's iPhone or Android app. Learn faster with spaced repetition

UNIT 7: Knee Unit. Expandable section. Add To Remove From Your Favorites. CHAPTER 41: Structure and Function of the Bones and Noncontractile Elements of the Knee. CHAPTER 45: Mechanics and Pathomechanics of Muscle Activity at the Ankle and Foot. Add To Remove From Your Favorites. CHAPTER 46: Analysis of the Forces on the Ankle and Foot. Visit http://ilectureonline.com for more math and science lectures!In this fifth of the seven part series I will show you how to find the force on a biceps l.. Muscle-level activations and muscle-tendon unit length changes provide sufficient information to obtain estimates of muscle-tendon mechanics, specifically muscle fiber force, muscle fiber length, muscle fiber velocity and tendon length (Arnold et al., 2010). Given measured muscle activity and joint kinematics, we were able to generate.

The purpose was to identify the effect of six weeks passive ankle stretching on muscle-tendon unit parameters in children with spastic cerebral palsy. Methods: Thirteen children (8-14 y) with quadriplegic/diplegic cerebral palsy were randomly assigned to either an experimental group (n=7) or a control group (n=6) 7 1. Mechanics of Muscle In studying the mechanical action of muscles 77 the individual muscle cannot always be treated as a single unit, since different parts of the same muscle may have entirely different actions, as with the Pectoralis major, the Deltoid, and the.

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  1. 1. Introduction. Children with spastic cerebral palsy (CP) experience significant alterations in soft tissue structures within the muscle-tendon unit (MTU), secondary to neurological impairment (Alhusani et al., 2010, Barber et al., 2011, Tardieu et al., 1988).Specifically, a shortening of the muscle through a loss of both in-series (Mohagheghi et al., 2008) and in parallel (Shortland et al.
  2. Muscle Fiber Typing. Initially, whole muscles were classified as being fast or slow based on speeds of shortening. 3 This division also corresponded to a morphological difference, with the fast muscles appearing white in some species, notably birds, and the slow muscles appearing red. The redness is the result of high amounts of myoglobin and a high capillary content. 3 The greater myoglobin.
  3. Chapter 9: Mechanics and Pathomechanics of Muscle Activity at the Shoulder Complex. Add To Remove From Your Favorites. Chapter 10: Analysis of the Forces on the Shoulder Complex during Activity. Unit 2:: Elbow Unit. Unit 7:: Knee Unit. Expandable section. Add To Remove From Your Favorites
  4. Moreover, it also improved the mechanics of skeletal muscle by increasing developed force (+31% vs. the control group, p<0.05) and maximal mechanical efficiency, activated the IGF1/mTOR/Akt pathway, and reduced the Smad2/3 pathway. Our results clearly show that the change in speed is a stimulus to control cardiac and skeletal muscle mass
  5. UNIT VII - The Knee: Objectives: At the completion of this unit the student will be able to: 1. This tuberosity is an important attachment for muscle. Also on the lateral surface is the interosseus border for attachment with the interosseus membrane that connects the tibia and fibula along the length of their shaft. and she should be.
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  7. The maximum force a muscle can generate depends on its physiological cross-section area . In fact the maximum force can be calculated by multiplying the PCA by constant (approximately 20 to 100 N.cm-2). In a non-pennate muscle this is simply the area of a slice taken in the middle of a muscle perpendicular to the line of pull. However as can be.

Figure 7-1 contrasts the three types of muscles found within the body. We will now explore each of these types in further depth. Unlike skeletal muscle, smooth muscle is involuntary and not under our conscious control. It is also called smooth muscle because it does not have the striped appearance of skeletal muscles B. The muscle twitch depends on the kind of muscle and is longer than the action potential. 1. Slow twitch fibers 2. Fast twitch fibers 3. The action potential is a trigger. C. Muscle force is determined by the number of motor units that are recruited. D. Muscle force is determined by the frequency of activation 7 1. Mechanics of Muscle In studying the mechanical action of muscles 77 the individual muscle cannot always be treated as a single unit, since different parts of the same muscle may have entirely different actions, as with the Pectoralis major, the Deltoid, and the. Skeletal muscle mechanics. 1. A muscle twitch is the response of a muscle to a single, brief threshold stimulus or response to a single action potential. It is too short or too weak to be useful E. g. blinking of the eye There are three phases to a muscle twitch Latent period Period of contraction Period of relaxation Computational and mathematical models are used to predict muscle force generation at multiple biological scales, including cross-bridge dynamics [79, 80], sarcomere and half sarcomere dynamics [81, 82], muscle fiber recruitment , micro-scale fiber mechanics [84, 85], muscle tissue dynamics [86,87,88], as well as limb and body locomotion . These.

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regulates actin mechanics. (found on the actin protein) Troponin (a protein) is attached to the protein tropomyosin and lies within the groove between actin filaments in muscle tissue. In a relaxed muscle, tropomyosin blocks the attachment site for the myosin crossbridge, thus preventing contraction. I.E. It blocks myosin from bonding Donate here: http://www.aklectures.com/donate.phpWebsite video: http://www.aklectures.com/lecture/slow-oxidative-fast-oxidative-and-fast-glycolytic-musclesFa..

Part 2 - Striations vs Striated Muscle 14:54; Part 3 - Muscle Structure 23:34; Part 3b - Building a Muscle 10:10; Part 4 - Relative Fiber Length 11:17; Part 4b - Non-Spanning Model 4:20; Part 5 - Motor Unit Distribution 13:40; Part 6a - Types of Contractions Revisited 8:25; Part 6b - Relative Distance of Shortening 7:11; Part 7 - Length-Tension. ever, studies to date that have quantified hamstrings muscle force, power, and work done during sprinting have collected data using a treadmill (6,7,39), evaluated the swing phase of the stride cycle only (6,39), obtained data for a single sub-ject only (33,39), or modeled the hamstring muscle complex as a single unit (33) Because skeletal muscle cells are long and cylindrical, they are commonly referred to as muscle fibers. Skeletal muscle fibers can be quite large for human cells, with diameters up to 100 μm and lengths up to 30 cm (7.6 in) in the Sartorius of the upper leg.During early development, embryonic myoblasts, each with its own nucleus, fuse with up to hundreds of other myoblasts to form the.

Diastasis recti (rectus diastasis) or divarication of the recti is a stretching of the linea alba with abnormal widening of the gap between the two medial sides of the rectus abdominis muscle (increased inter-recti distance).. The degree of widening needed for the diagnosis is controversial, with the degree of abdominal protrusion (rather than the degree of widening) often defining whether it. 7. Thousands of myofibrils are tightly packed together in a _____ arrangement to form the muscle fiber. 8. A _____ muscle is a muscle tissue that features repeating functional units called sarcomeres current length relations. A muscle contains two types of sensors; i.e. muscle spindle and golgi tendon organ, which give rise to the feedback control of the muscle length and muscle contraction velocity. In this study a 1-D model of a muscle is formed step by step in Simulink. In the models the muscle mechanics has been investigate

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In muscle physiology, physiological cross-sectional area (PCSA) is the area of the cross section of a muscle perpendicular to its fibers, generally at its largest point. It is typically used to describe the contraction properties of pennate muscles. It is not the same as the anatomical cross-sectional area (ACSA), which is the area of the crossection of a muscle perpendicular to its. The effect of obesity on muscle strength and structure in adolescent individuals. By assessing both neural and muscular components of force generating capacity, Blimkie et al. were the first to extensively examine skeletal muscle performance in obese and non-obese adolescent males.The main observation from the Blimkie study was lower quadriceps femoris muscle activation in obese compared to. Timing matters: tuning the mechanics of a muscle-tendon unit by adjusting stimulation phase during cyclic contractions Gregory S. Sawicki, Gregory S. Sawicki * 1. Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695. 4.7 The force of a muscle depends on sarcomere length; 4.8 Getting the most out of restricted muscle performance; 5 Muscle mechanics. 5.1 Contractile units in series and in parallel; 5.2 Movement, strength and work; 5.3 Each muscle is a unique organ delivering unique torques; 5.4 Torque and equilibria; 5.5 Fibrous architecture of muscles Running is thought to be an efficient gait due, in part, to the behavior of the plantar flexor muscles and elastic energy storage in the Achilles tendon. Although plantar flexor muscle mechanics.

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gastrocnemius (MG) muscle-tendon unit lengthening was associated with MG fibre shortening, and vice versa, for dis-tinct phases of the cat step cycle [ 7](Fig.3). This uncoupling between muscle and fascicle length changes has been ob-served in dozens of preparations in the meantime for iso-metric (e.g. [4, 5, 8, 9]), and for dynamic in vivo huma 46 Respiratory System Mechanics and Respiratory Muscle Function. Cesare Gregoretti, Vito Marco Ranieri. In its simplest form, the respiratory system can be modeled as a balloon connected to a tube. The balloon represents the elastic element (lungs and chest wall), and the tube represents the resistive element (conducting airways) Muscle Mechanics | 9,000 sq.ft Personal Training Gym | BEST Personal Trainers in Los Angeles | Get Fit & In-Shape with the most ELITE Personal Trainer

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Unit 2. Lagrangian and Hamiltonian Mechanics BANG! A fiendish 30-ton war machine hurls a 5-ton load of rocks, garbage, and bodies of plague victims onto panicked warriors. Classical mechanics of this machine are the least of the warriors' worries. Mechanics is our job and a comparatively easy one: Derive and apply Lagrange and Hamilton. At the latest since Hill's (1938) [] classic work on the heat of shortening in frog skeletal muscles, we know that elasticity and muscle elastic components play a crucial role in the mechanics of muscle contraction.Hill (1938) [] derived a model of skeletal muscle that had a contractile element in series with an elastic element (Fig 1).The terms in series and elastic refer to the. Skeletal Muscle Mechanics Length-Tension Curves Lab Report ORDER A LAB REPORT OR ANY PAPER Abstract Skeletal muscles are the main organ system that are responsible for movement and force generation. To understand the normal movement of the body parts, a study on the skeletal muscles mechanical properties should be done. The importance of studying the Skeletal Muscle Mechanics Length. Module P2.7 Rotational mechanics 1 Opening items 1.1 Module introduction 1.2 Fast track questions 1.3 Ready to study? 2 Torque 2.1 Introduction to torque 2.2 Work and power 2.3 The centre of mass 2.4 Combining torques1— 1a scalarapproach 2.5 Translational and rotational equilibrium 3 Torques using vector notation 3.1 Unit vectors and vector.

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7. To produce the required amount of energy storage, the adult muscle fibres must shorten slightly more than those of the fourth instar, but they must produce more than twice the force per unit area. 8. The strain on the apodeme is similar in adults and hoppers, and greater at the distal than at the proximal end The in vivo characterization of the passive mechanical properties of the human triceps surae musculotendinous unit is important for gaining a deeper understanding of the interactive responses of the tendon and muscle tissues to loading during passive stretching. This study sought to quantify a comprehensive set of passive muscle-tendon properties such as slack length, stiffness, and the stress. 1.2. Tissue based models of contraction. Determining the start of any field is contentious. However, the study by A.V. Hill in 1938 [] described fundamental properties of muscle mechanics that continue to inform muscle physiology studies today.In a series of elegant experiments, Hill related the release of energy by muscle, the mechanical work performed by the muscle, the force of contraction. the muscle-tendon, exists, and c) the interplay between muscle mechanics and activation, by manipulating the testing position on the dynamometer, stabilisation and concurrent activation of remote muscles Muscle-Tendon Unit Mechanics Reduced resistance to stretch and muscle strength are frequently considered as injury risk factors [ 2 ]. However, if the hamstrings have different L MTUs, then one may suggest that it is not the extensibility or force-generation capacity of the hamstrings as a group, but rather the properties of each individual.

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Timing matters: tuning the mechanics of a muscle-tendon unit by adjusting stimulation phase during cyclic contractions Gregory S. Sawicki1,*, Benjamin D. Robertson1, Emanuel Azizi2 and Thomas J. Roberts3 ABSTRACT A growing body of research on the mechanics and energetics of terrestrial locomotion has demonstrated that elastic element Effect of exercise-induced enhancement of the leg-extensor muscle-tendon unit capacities on ambulatory mechanics and knee osteoarthritis markers in the elderly. Karamanidis, K, Oberländer, KD, Niehoff, A, Epro, G and Brüggemann, G-P (2014) The multiscale mechanical interaction of the muscle spindle within the muscle tendon unit revealed isometric force generating conditions in which muscle spindle firing followed intrafusal muscle fiber force, which can either resemble or differ from muscle-tendon unit force or length depending on the relative amounts of alpha and gamma motor. Although plantar flexion force steadiness (FS) is reduced in persons with Parkinson's disease (PD), the underlying causes are unknown. The aim of this exploratory design study was to ascertain the influence of maximal voluntary contraction (MVC) force and gastrocnemius-Achilles muscle-tendon unit behaviour on FS in persons with PD. Nine persons with PD and nine age- and sex-matched non. stimulation measurements [compare [7, Fig. 9(a)-(d)] to [3, Fig. 2] and Fig. 4(f)-(i) here]. Recently, Durfee and Palmer designed a nonlinear nonisometric muscle model that can predict force output with reasonable accuracy for a wide range of simultaneously varying muscle lengths, velocities, and levels of motor unit recruitment [9]

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When it comes to optimizing athletic performance, speed, and power output, mastering your jumping and landing mechanics are key. Additionally, learning to properly jump and land with correct biomechanics can do wonders for improving muscle function, stability, motor control, body composition, and overall fitness levels not only for athletes but also for general populations and fitness enthusiasts FS varies with age, sex, muscle strength, and limb position, and is influenced by the nervous system and neuromuscular factors such as motor unit properties and tendon mechanics [12,13,14,15,16,17]. Plantar flexion strength and FS are less in persons with PD than healthy controls [ 8 ], but the reasons for these differences are unclear Engineering Mechanics: Statics Bedford&Fowler. Jw Jw. Download PDF. Download Full PDF Package. This paper. A short summary of this paper. 12 Full PDFs related to this paper. Read Paper. Engineering Mechanics: Statics Bedford&Fowler

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Eur Respir J 1994; 7:398. Watson, L. A method for measuring sniff nasal inspiratory pressure using the PK Morgan Pm meter. Inspire, the Official J Assoc Respir Technicians Physiologists 1997; 1:14. Enright PL, Kronmal RA, Manolio TA, et al. Respiratory muscle strength in the elderly. Correlates and reference values RESEARCH ARTICLE Ca2 dependency of limb muscle fiber contractile mechanics in young and older adults Laura E. Teigen,1 X Christopher W. Sundberg,1,2 Lauren J. Kelly,1 X Sandra K. Hunter,2 and Robert H. Fitts1 1Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin; and 2Department of Physical Therapy, Marquette University, Milwaukee, Wisconsi Now let us consider the response of the Maxwell model to a unit step stress: In this case, a stress s0 is applied instantaneously and then kept constant over time. Thus, the rate of change of stress is zero and the Maxwell constitutive model becomes: We can solve the above equation simply by integrating with respect to time

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Author summary Computer-based numerical simulations of the heart are increasingly assuming a recognized role in the context of computational medicine and cardiology. They are based on mathematical models describing the different physical phenomena occurring during an heartbeat. Among these models, a pivotal role is played by those describing how cardiomyocytes—the cardiac muscle cells. TENS 7000 Digital TENS Unit With Accessories - TENS Unit Muscle Stimulator For Back Pain, General Pain Relief, Neck Pain, Muscle Pain 4.7 out of 5 stars 50,192 #1 Best Seller in Muscle Stimulators & Accessorie Transcutaneous electrical nerve stimulation (TENS) is a therapy that uses low voltage electrical current to provide pain relief. A TENS unit consists of a battery-powered device that delivers electrical impulses through electrodes placed on the surface of your skin. The electrodes are placed at or near nerves where the pain is located or at. Respiratory mechanics refers to the expression of lung function through measures of pressure and flow. From these measurements, a variety of derived indices can be determined, such as volume, compliance, resistance, and work of breathing. Plateau pressure is a measure of end-inspiratory distending pressure. It has become increasingly appreciated that end-inspiratory transpulmonary pressure. 1 Does long-term passive stretching alter muscle-tendon unit mechanics in children with spastic cerebral palsy? Nicola Theis a, PhD, Thomas Korff b, PhD and Amir A. Mohagheghi ,c PhD* aSchool of Sport, Health and Applied Science, St Mary's University, Strawberry Hill, Middlesex, TW12 4SX, U

Stretch of the muscle component slowed considerably when the biceps femoris muscle was activated, resulting in slightly earlier occurrence of peak muscle stretch. Further, the muscle component shortened considerably less than the musculotendon unit between 80 and 90% of the gait cycle, while the tendon reached a peak stretch of 15 mm ( Fig. 4 ) Become comfortable with modifying existing code that models muscle activation and muscle-tendon mechanics. and the distance between the fixed ground supports is 0.7 m. Thus, each muscle-tendon actuator is 0.3 m long when the block is centered. the delay between a motor unit action potential and the development of peak force has been. Anatomy of the Spine. The spine consists of 33 bones or vertebrae, 24 of which are separate bones allowing movement and 9 which are fused together. The 5 sections of the spine or vertebral column are the cervical, thoracic, lumbar and sacrum which includes the coccyx CONDUCTION AND MUSCLE MECHANICS ANSW ER KEY 1. M us cle cells are long, multinucleated cells that are shaped s omething like cylinders that taper near W here C m is the capacitance per unit area membrane and A is the area. The number of charges 2 = 19635 x 10-8 cm3 x 10-3 L cm-3 = 1.96x10-7 L The total number of ca tions is 150 x 10-3. 2.4 Unit Cell Processes Limitations of the paradigm . 2.5 Examples of Unit Cell Processes 2.6 Contraction and Migration . 2.7 Summary of Effects of Exogenous Mechanical Forces on Cells and the Generation of Contractile Force by Cell

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Knowledge regarding the effects of athletic training on the properties of muscle and tendon in preadolescent children is scarce. The current study compared Achilles tendon stiffness, plantar flexor muscle strength and vertical jumping performance of preadolescent athletes and non-athletes to provide insight into the potential effects of systematic athletic training. Twenty-one preadolescent. Maximum values for isometric strength, dynamic strength, and speed of movement (MEV) in the quadriceps muscle were measured in 114 male subjects who were between 11 and 70 yr. Biopsy samples were taken from the quadriceps muscle in 51 of the subjects (22-65 yr. old) 1. Anatomy and Mechanics Introduction The respiratory system carries out several homeostatic functions, including: 1. gas exchange between the atmosphere and the blood to provide an adequate supply of oxygen to tissues and to remove carbon dioxide (CO 2) generated in oxidative metabolism. O 2 + Food = CO 2 + H 2 O + AT We measured muscle, tendon and joint mechanics in an elbow extensor of a small fruit bat during ascending flight. At the end of downstroke, the tendon was stretched by elbow flexion as the wing was folded. At the end of upstroke, elastic energy was recovered via tendon recoil and extended the elbow, contributing to unfurling the wing for.

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Effect of Exercise-Induced Enhancement of the Leg-Extensor Muscle-Tendon Unit Capacities on Ambulatory Mechanics and Knee Osteoarthritis Markers in the Elderly Kiros Karamanidis , 1 , 2 , * Kai Daniel Oberländer , 1 , 3 Anja Niehoff , 1 , 4 Gaspar Epro , 1 and Gert-Peter Brüggemann 1 , Effect of Exercise-Induced Enhancement of the Leg- Extensor Muscle-Tendon Unit Capacities on Ambulatory Mechanics and Knee Osteoarthritis Markers in the Elderly Kiros Karamanidis1,2*, Kai Daniel Oberla¨nder1,3, Anja Niehoff1,4, Gaspar Epro1, Gert-Peter Bru¨ggemann1,4 1 Institute of Biomechanics and Orthopaedics, German Sport University of Cologne, Cologne, Germany, 2 Department of. Chapter 3. Lagrangian GCC derivatives and kinetic energy Conventional classical mechanics starts with Newton's Cartesian F=m equations (2.1.1) as the main classical axiom following momentum conservation (2.1) of Unit 1. They relate acceleration component for each mass to a corresponding force component F x, or F y on that mass due to outside forces and other masses