Acceleration
A body moving faster and faster in a straight line, in classical physics, is said to be accelerated. A body moving slower and slower in a straight line, in classical physics, is decelerating, or minus acceleration. A body alternating faster and slower in a single direction is said to be accelerated.
And finally, a body moving at any rate in any curved trajectory is said to be accelerated.
In curved motion, at any instant a body is always trying to go straight by Newton's Law I; thus constantly changing direction in a curve, is constantly having or creating a new tangent line away from the curve. In a technical paradoxical manner of speaking: For each and every infinitesimal point and instant the body traveling in curved motion, has to slow and stop in the direction it was going, and speed up in the new direction repetitively. (Actually, this phenomena of starting and stopping is not a reality. Matter in motion has constant internal motion also, and when forced in curved motion the minute body parts are flexing and shifting to make the bending new curve directions, and or the solid body if turning about a corner point, as a hinge flap, is actually flipping, and thus every point on and within the body is moving in various curves. ) In nature, true curved motion can involve the atoms and molecules flexing in motion within the body, and can require millions of continual motions to make a turn. It can also be demonstrated that it takes successive pressure force actions to turn a body... In physics a single arrow is used to portray a force... when actually in all and any force scenarios... a multitude of force actions are required, and is called net force action. But, they act to focus, and give a general single direction result.
In extreme strictness there is no such thing as a perfect straight line, and no such thing as perfect uniform motion. Thus the curved part of the definition of acceleration, in nature, is the only reality condition.
These writings are not to teach acceleration, but to review, and to focus on the importance of the curved paths of any, and all bodies of matter.
Anytime a body is moving in a curved path is being accelerated! All bodies in the Universe are in motion. All bodies in the Universe are moving in curved paths. Thus, however great, or small... all bodies are in constant acceleration. All bodies continually have forces acting upon them changing their state.
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Mechanical Acceleration__
Pushing or applying pressure upon a body causing it to move faster and faster... is not difficult to comprehend. If the push is applied to our arm, for example, we can sense the difference compared to normal conditions. We feel the movement of tissue at the local area of contact. This is a sensed differential of pressure within the material makeup of our arm, and as the differential exists the acceleration into body tissue is happening.
Gravitational Acceleration__
However, we do not directly sense Gravitational Acceleration! However, we do sense the sudden stop at the end of a fall! We often sense motion with our sight, relating to our surroundings. We might feel wind passing. And, we feel the weight of objects. But, these are not causing the acceleration, of a fall.
Why don't we physically feel something pushing us when we drop? Simply because every minute particle in our body is being acted upon almost simultaneously. (And there is a good argument for the possibility that gravity exerts pressure from idle or virtual particles in space upon the idle or virtual particles within the space of a bodies atoms; thus it would not pressure directly, acting or interacting, with the upper level particulates of matter.) It is now said to be confirmed experimentally, gravity operates at the speed of light. Your body atoms are 99.99999+%... space, and your physical touch sensitivity differential is only good to maybe 1/16 of an inch. From atom to atom you don't have any sensitivity reference. It should not be very difficult for the actions of gravity to act from head to toe almost instantly! So, when an atom in your head is being set into motion__ another within your foot is also starting to move. And__ if it is true that Space externally from matter interacts with the internal Space of atoms... there could very well be changes of state at the level of Space interaction... as with fields in Space... that are the phenomena doing the gravitating, and our body matter is just moving along with its internal Space in motion, and or the fields in Space changing charge states, or something else, but having to to do with space instead of a shove of physical material matter.
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As mentioned above, I will elaborate in my section upon Change of State, that no matter however slight, sharp or erratic... when taken to extremes__ any body, is always in curved motion. So when you put this together with the fact that all curved motion is accelerated motion... the whole Universe is in constant acceleration! This can also be substantiated by the fact that there is no such thing as uniform motion with everything in curved accelerated motion.
All motion in the Universe, is accelerated curved motion.
There will be more on acceleration in the other sections, but this page points out the major reasoning I have come up with for acceleration: that all curved motion is accelerative, and all motion is curved... thus all motion is accelerative.
Acceleration is a name for an action of motion, not the motion. It describes a type of motion that is a reality. But, acceleration is not the reality. Motion and pressure as changing of states is the reality. The Universe would be fine without the word called acceleration... It doesn't care what curved motion is called, or any motion, but a Universe without motion and pressure... as change of state, is in real trouble...
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Page Relevant Quotes
"In mechanical terms, a body is subject to acceleration if the amount of ground covered in unit time is changing (either increasing, so that the body is accelerating in the usual sense of the word, or else decreasing, so that the body is decelerating or slowing down). The body is also said to be undergoing acceleration if its direction of motion is changing, even if its actual velocity along its trajectory is not." Quanta: J. Andrade e Silva, G. Lochak
"Speed is measured in derived units such as mi/hr or m/s, but the statement of a velocity must include a direction.
All velocities are relative. The velocity of a body is always relative to another body. When the other body is not mentioned it is understood to be the earth." Principles of College Physics; George Shortley, Dudley Williams.
