Continuum Mechanics is the branch of mechanics which deals with the study of deformation and motion of continuous bodies. Primarily, a continuous solid body can be categorized into two types: (i) Rigid body and (ii) Elastic body. When external forces are applied on the body and the relative positions of its particles do not change at all, the body is said to be perfectly rigid body, otherwise it is said to be elastic body. A body is called strained, if under the influence of some external forces, the relative positions of its particles get altered. The change in the relative position of particles is called deformation. In practice, all solid bodies undergo deformation up to some extent by the application of suitable forces upon them. There are certain bodies which regain their original configuration when the deforming forces are removed. For example, the wire regains its original length after …show more content…
Rigid body motion does not change the length of a vector joining the pair of points inside the body and has no concern with the strain analysis. When external forces are applied on an elastic body, the body undergoes deformation. Due to the elasticity of the body, there comes into play a force which resists the deformation. This force is called stress force. Clearly, the deformation of the body is accompanied by the stress force. In other words, stress and strain occur together in inelastic body. There are two types of elastic deformation: (i) Dilatation and (ii) Shear strain set up in the body in such a way that there is a change only in volume but no change in shape, is called dilatation. In the shear deformation, there is a change in the shape of the body without a change in its volume. Dilatations are further categorized into two kinds: compression, in which volume is reduced; and rarefaction, in which the volume is
tension of the system. Their orientation at the interface varies, depending on the components of
This paper presents how Labeling theory and strain theory can explain the crimes that The White family from West Virginia commit on a daily basis. The wonderful White of West Virginia portrays corruption and poverty. They do not conform to any authority or rules; all they want to do is fuss, fight and party. The White family takes part in shoot-outs, robberies; gas huffing, drug dealing, pill popping and murders. They are famously known for their Hill Billy tap dancing and wild criminal ways. West Virginia being the poorest state in the United States they do not have the resources to a good education system or available employment. Therefore, frustration sets in, leading to failed aspirations causing the Whites to resort to violent and illegal ways to survive in a declining economy, to obtain a slight chance to their perspective of the American dream. However, being labeled as the rebels of the south just makes that slight chance of the American dream much harder to obtain.
Muscle activity, including generating force and moving limbs through lengthening and shortening, is an important influence on beneficial tissue stress. Muscles adapt quickly to periods of lower or higher stress and demonstrate obvious visual and functional changes. At a tissue level, the Physical Stress Theory (PST) states that muscle adaptations are consistent with other high and low strain tissue adaptation models. Low stress/activity associated with immobilization results in decreases in contractile protein, fiber diameter, peak tension and power. Evidence supports the idea that tissues within the musculoskeletal system atrophy and become less tolerant of physical stress if stress on the tissue diminishes below a baseline level.3 In addition,
It is Isometric. This means that it is performed in a static position. By so doing, the force of the muscles contracts over the bones, making them thicker and stronger.
A muscle trauma which, is also known as a muscle strain is an injury which, occurs within the muscle tendon. The pain can be classified into three different sections which are; mild, moderate and severe. The main cause of a muscle strain is when the muscle is overstretched since the muscles have probably been working too hard. If a muscle tear occurs, it can also damage the attaching tendons within the muscles because, the muscle tissues are stretched and then torn (2).
According to Neumann, a force can be considered a push or pull that can produce, arrest or modify movement and can be measured as F=ma (Neumann, 2010). Force can also be considered the load. In regards to muscle contraction force relative to the joint, the force can be the internal force produced by the muscle itself, the force of gravity or the force of the particular load/weight. Torque is a cross product between force and the distance of the force from the fulcrum and is the ability of a force to cause rotation on a lever. Torque is a measure of how much a force acting on an
Mechanical Engineering 130.2 (2008): 6 - 7. Academic Search Complete. Web. The Web. The Web.
Kinematics unlike Newton’s three laws is the study of the motion of objects. The “Kinematic Equations” all have four variables.These equations can help us understand and predict an object’s motion. The four equations use the following variables; displacement of the object, the time the object was moving, the acceleration of the object, the initial velocity of the object and the final velocity of the object. While Newton’s three laws have co-operated to help create and improve the study of
These properties can be used for design and analysis of engineering structures, and for developing new materials that better suit a specified use. [8] Tensile tests are simple, relatively inexpensive, and fully standardised. By pulling on something, you will very quickly determine how the material will react to forces being applied in tension. As the material is being pulled, you will find its strength along with how much it will elongate and one of the more basic tests is to determine stress – strain relationships. [10] A simple uniaxial test consists of slowly pulling a sample of material in tension until it breaks. The major parameters that describe the stress-strain curve obtained during the tension test are the tensile strength (UTS), yield strength or yield point (σy), elastic modulus (E), percent elongation (∆L%) and the reduction in area (RA%). Toughness, Resilience, Poisson’s ratio (ν) can also be found by the use of this testing technique. 0.2 % off-set method is a commonly used method to determine the yield strength. Yield strength (σy) (0.2%) is found by drawing a parallel line to the elastic region and the point at which this line intersects with the stress-strain curve is set as the yielding point. [9] The following figure is the tensile tester that is used to test the
Chapter 14 obtain the principle of work and energy by combined the equation of motion in the tangential direction, ƩFt = mat with kinematics equation at ds = v dv. For application, the free body diagram of the particle should be drawn in order to identify the forces that do work. However, Chapter 18 use kinetic energy that the sum of both its rotational and translational kinetic energy and work done by all external forces and couple moments acting on the body as the body moves from its initial to its final position. For application of Chapter 18, a free-body diagram should be drawn in order to account for the work of all of the forces and couple moments that act on the body as it moves along the
Gastrulation is one of the most important phases in the life of multicellular organisms. Blastula, a single layered cell structure converts into trilaminar structure with three layers, known as gastrula. The word ‘gastrula’ means stomach, since stomach (archenteron) is the first thing formed during gastrulation.
Law of elasticity is known as Hooke’s law, showing the relationship between the forces applied to a spring and its elasticity, which states that relationship between small deformation of the object and the displacement or size are directly proportional to loading and the deforming force. According to Hooke’s law, elastic behaviour of solids could explain by the fact that in component ions, molecules, or atoms from normal positions, which is small deformation, are also proportional to the force that causes the displacement. The deforming force might be applied to a solid by squeezing, compressing, stretching twisting, or bending. Accordingly, spring will return to its primary size and shape upon discharge of the load (Tega, 2010).
Sir Isaac Newton is the man well known for his discoveries around the term, Motion. He came up with three basic ideas, called Newton’s three laws of motion.
The science of fluid mechanics is neither new nor biblical; however, most of the progress in this field was made in the 20th century. Therefore it is appropriate to open this text with a brief history of the discipline, with only a very few names mentioned.
Here, we can use the vectors to use the Pythagorean Theorem, a2 + b2 = c2, to find the speed and angle of the object, which was used in previous equations.