In physics Physics is a natural science; it is the study of matter and its motion through spacetime and all that derives from these, such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the world and universe behave, a force is any external agent that causes a change in the motion of a free body, or that causes stress In continuum mechanics, the concept of stress, introduced by Cauchy around 1822, is a measure of the average amount of force exerted per unit area of a surface within a deformable body on which internal forces act . In other words, it is a measure of the intensity or internal distribution of the total internal forces acting within a deformable in a fixed body.[1] It can also be described by intuitive concepts such as a push or pull that can cause an object with mass Mass is a concept used in the physical sciences to explain a number of observable behaviours, and in everyday usage, it is common to identify mass with those resulting behaviors. In particular, mass is commonly identified with weight. But according to our modern scientific understanding, the weight of an object results from the interaction of its to change its velocity In physics, velocity is defined as the rate of change of position. It is a vector physical quantity; both speed and direction are required to define it. In the SI system, it is measured in meters per second: (m/s) or ms-1. The scalar absolute value (magnitude) of velocity is speed. For example, "5 meters per second" is a scalar and not a (which includes to begin moving from a state of rest Newton's laws of motion are three physical laws that form the basis for classical mechanics. They are:), i.e., to accelerate In physics, and more specifically kinematics, acceleration is the change in velocity over time. Because velocity is a vector, it can change in two ways: a change in magnitude and/or a change in direction. In one dimension, acceleration is the rate at which something speeds up or slows down. However, as a vector quantity, acceleration is also the, or which can cause a flexible object to deform In materials science, deformation is a change in the shape or size of an object due to an applied force. This can be a result of tensile forces, compressive (pushing) forces, shear, bending or torsion (twisting). Deformation is often described as strain. Force has both magnitude In elementary mathematics, physics, and engineering, a vector is a geometric object that has both a magnitude (or length) and direction. A vector is frequently represented by a line segment with a definite direction, or graphically as an arrow, connecting an initial point A with a terminal point B, and denoted by and direction Direction is the information contained in the relative position of one point with respect to another point without the distance information. Directions may be either relative to some indicated reference , or absolute according to some previously agreed upon frame of reference (New York City lies due west of Madrid). Direction is often indicated, making it a vector In elementary mathematics, physics, and engineering, a vector is a geometric object that has both a magnitude (or length) and direction. A vector is frequently represented by a line segment with a definite direction, or graphically as an arrow, connecting an initial point A with a terminal point B, and denoted by quantity. Newton's second law Newton's laws of motion are three physical laws that form the basis for classical mechanics. They are: states that an object with a constant mass will accelerate in proportion to the net force A net force, Fnet = F1 + F2 + … is a vector produced when two or more forces { F1, F2, … } act upon a single object. It is calculated by vector addition of the force vectors acting upon the object. A net force can also be defined as the overall force acting on an object, when all the individual forces acting on the object are added together acting upon and in inverse proportion to its mass. Equivalently, the net force on an object equals the rate A time derivative is a derivative of a function with respect to time, usually interpreted as the rate of change of the value of the function. The variable denoting time is usually written as at which its momentum In classical mechanics, momentum is the product of the mass and velocity of an object (p = mv). For more accurate measures of momentum, see the section "modern definitions of momentum" on this page. It is sometimes referred to as linear momentum to distinguish it from the related subject of angular momentum. Linear momentum is a vector changes.[2] See also thrust Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.
Forces acting on three-dimensional objects may also cause them to rotate A rotation is a movement of an object in a circular motion. A two-dimensional object rotates around a center of rotation. A three-dimensional object rotates around a line called an axis. If the axis of rotation is within the body, the body is said to rotate upon itself, or spin—which implies relative speed and perhaps free-movement with angular or deform In continuum mechanics, deformation is the change in shape and/or size of a continuum body after it undergoes a displacement between an initial or undeformed configuration , at time , and a current or deformed configuration , at the current time .[clarification needed], or result in a change in pressure Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure or even change volume in some cases. The tendency of a force to cause changes in rotational speed Angular acceleration is the rate of change of angular velocity over time. In SI units, it is measured in radians per second squared , and is usually denoted by the Greek letter alpha (α) about an axis is called torque Torque, also called moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist. Deformation and pressure are the result of stress In continuum mechanics, the concept of stress, introduced by Cauchy around 1822, is a measure of the average amount of force exerted per unit area of a surface within a deformable body on which internal forces act . In other words, it is a measure of the intensity or internal distribution of the total internal forces acting within a deformable forces within an object.[3][4]
Since antiquity, scientists have used the concept of force in the study of stationary Statics is the branch of mechanics concerned with the analysis of loads on physical systems in static equilibrium, that is, in a state where the relative positions of subsystems do not vary over time, or where components and structures are at a constant velocity. When in static equilibrium, the system is either at rest, or its center of mass moves and moving In physics the term dynamics customarily refers to the time evolution of physical processes. These processes may be microscopic as in particle physics, kinetic theory, and chemical reactions, or macroscopic as in the predictions of statistical mechanics and nonequilibrium thermodynamics objects. However, descriptions of forces by Aristotle Aristotle (384 BC – 322 BC) was a Greek philosopher, a student of Plato and teacher of Alexander the Great. He wrote on many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, politics, government, ethics, biology, and zoology. Together with Plato and Socrates (Plato's teacher), Aristotle is one of the most incorporated fundamental misunderstandings, which, despite advances made by the third century BC philosopher Archimedes Archimedes of Syracuse was a Greek mathematician, physicist, engineer, inventor, and astronomer. Although few details of his life are known, he is regarded as one of the leading scientists in classical antiquity. Among his advances in physics are the foundations of hydrostatics, statics and the explanation of the principle of the lever. He is from studies of simple machines A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage to multiply force. A simple machine uses a single applied force to do work against a single load force. Ignoring friction losses, the work done on the load is equal to,[5] persisted for many centuries. By the seventeenth century, Sir Isaac Newton Sir Isaac Newton FRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian who is perceived and considered by a substantial number of scholars and the general public as one of the most influential men in history. His Philosophiæ Naturalis Principia Mathematica, published in 1687, is by itself corrected these misunderstandings with mathematical insight that remained unchanged for nearly three hundred years.[4] By the early 20th century, Einstein Albert Einstein (pronounced /ˈælbərt ˈaɪnstaɪn/; German: [ˈalbɐt ˈaɪ̯nʃtaɪ̯n] ; 14 March 1879 – 18 April 1955) was a German-Jewish theoretical physicist who acquired Swiss and later American citizenship. He is best known for his theories of special relativity and general relativity. Einstein received the 1921 Nobel Prize in Physics in his theory of general relativity General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics. It unifies special relativity and Newton's law of universal gravitation, and describes gravity as a geometric property of space and time, or spacetime successfully predicted relativistic adjustments to Newton's model for gravity by ushering in the concept of a space-time In physics, spacetime is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space being three-dimensional and time playing the role of a fourth dimension that is of a different sort than the spatial dimensions. According to certain Euclidean space perceptions, the universe has three continuum.
The recent theory of particle physics Particle physics is a branch of physics that studies the elementary constituents of matter and radiation, and the interactions between them. It is also called high energy physics, because many elementary particles do not occur under normal circumstances in nature, but can be created and detected during energetic collisions of other particles, as known as the Standard Model The Standard Model of particle physics is a theory of three of the four known fundamental interactions and the elementary particles that take part in these interactions. These particles make up all visible matter in the universe. The standard model is a gauge theory of the electroweak and strong interactions with the gauge group SU×SU(2)×U(1) associates forces at the level of quantum mechanics Quantum mechanics are a set of principles describing physical reality at the atomic level of matter (molecules and atoms) and the subatomic (electrons, protons, and even smaller particles). These descriptions include the simultaneous wave-like and particle-like behavior of both matter and radiation ("wave–particle duality"). In the. The Standard Model predicts that exchange particles called gauge bosons In particle physics, gauge bosons are bosonic particles that act as carriers of the fundamental forces of nature. More specifically, elementary particles whose interactions are described by gauge theory exert forces on each other by the exchange of gauge bosons, usually as virtual particles are the fundamental means by which forces are emitted and absorbed. Only four main interactions are known: in order of decreasing strength, they are: strong In particle physics, the strong interaction, or strong force, or color force, holds quarks and gluons together to form protons, neutrons and other particles. The strong interaction is one of the four fundamental interactions, along with gravitation, the electromagnetic force and the weak interaction. The word strong is used since the strong, electromagnetic In physics, the electromagnetic force is the force that the electromagnetic field exerts on electrically charged particles. It is the electromagnetic force that holds electrons and protons together in atoms, and which hold atoms together to make molecules. The electromagnetic force operates via the exchange of messenger particles called photons, weak The weak interaction is one of the four fundamental interactions of nature. In the Standard Model of particle physics, it is due to the exchange of the heavy W and Z bosons. Its most familiar effect is beta decay (or the emission of electrons or positrons by neutrons in atomic nuclei) and the associated radioactivity. The word weak derives from, and gravitational Newton's law of universal gravitation is a general physical law derived from empirical observations by what Newton called induction. It describes the gravitational attraction between bodies with mass. It is a part of classical mechanics and was first formulated in Newton's work Philosophiae Naturalis Principia Mathematica , first published on 5.[3] High-energy particle physics Particle physics is a branch of physics that studies the elementary constituents of matter and radiation, and the interactions between them. It is also called high energy physics, because many elementary particles do not occur under normal circumstances in nature, but can be created and detected during energetic collisions of other particles, as observations Observation is either an activity of a living being , consisting of receiving knowledge of the outside world through the senses, or the recording of data using scientific instruments. The term may also refer to any datum collected during this activity made during the 1970s and 1980s confirmed that the weak and electromagnetic forces are expressions of a more fundamental electroweak In particle physics, the electroweak interaction is the unified description of two of the four fundamental interactions of nature: electromagnetism and the weak interaction. Although these two forces appear very different at everyday low energies, the theory models them as two different aspects of the same force. Above the unification energy, on interaction.[6]
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Q. I am zoning out on a problem dealing with an object on an incline plane. Accordingly, the object on the incline has two forces acting on it, the normal force and the frictional force. I just don't get why the object would not be in motion when the frictional frorce is less than or equal to the normal force.
Asked by crazy girl - Wed Jan 21 00:02:54 2009 - - 3 Answers - 0 Comments
A. Normal force is essentially equal to the pressure that an object puts on the surface upon which it rests. More normal force would equal more friction (heavier objects are harder to move, right??) On an inclined plane, it's the force of gravity down the slope that opposes friction. Normal force will always and forever be perpendicular to the force of friction, so it cannot oppose.
Answered by Chad P - Wed Jan 21 00:10:46 2009
