With initial data for each of the moving body can calculate the value of its acceleration, velocity, position (coordinates) and so forth. All these calculations are performed within the kinematics.However, this branch of science does not study the processes themselves, arising from the mechanical motion.Answer questions about the characteristics of movement, due to the acceleration pulse dynamics can.
Take boxes with one match in and start it on the table to move in the same direction with the same speed.What happens to the match?She is resting or moving?It all depends on what system we choose the main reference.In relation to the match box is at rest, but if you look at what is happening on the part of (for example, the same table), it moves.Overall, in both cases, that the constant speed match.To change it you need to have on the match boxes and external influence, for example, to push from the table.This is what characterized the inertial reference system.Let us assume that we are in a box next to a match.Since the external influence is not obvious at the moment of the fall you would think that the match itself was set in motion by acquiring acceleration pulse.But if you look at what is happening on the table, then the behavior of the match easily explained by the change speed box.In fact, we have described the inertial and non-inertial reference system.For the first characteristic of the action of external forces, and for the second resulting acceleration can not be explained by external forces.In this example, the inertial reference system bound to the surface of the table and any other object outside the box, since it is obvious external influence on the object under study.The problem of reference systems interested in such prominent scholars of antiquity, Galileo and Aristotle.Only in the 17th century, Isaac Newton, based on their work formulated his first rule of inertia, better known as Newton's first law.
It states that permitted the existence of such frames in which the body does not appear in the external action of other bodies, and the velocity does not change either by value or direction.If the effects of a few, but they are balanced, it acts the same rule, which is used inertial reference systems (ISO).If we consider a system of reference relative to the other, at constant speed and significance of the module, it is possible to argue that in nature there are many ISO.Consequently, the inertial reference systems all around us.
much easier to understand Newton's first law, if familiar with the findings of his predecessors - Aristotle and Galileo.
Aristotle argued that if the body does not appear to have any third-party effects, the natural state it - peace.In the case of moving the body with a constant speed must be present outside force.
Galileo supplemented these findings: the absence of external influence does not mean that the body can not move smoothly and without changing direction.The very same force that has an effect, wasted compensation of gravity, friction, and so forth.
inertial system is completely based on the first law, according to which any body is at rest or in uniform motion as long as the external force does not change its state.An important feature: the law can be carried out not in all possible reference systems.
Inertial brilliantly supported and actively used in celestial mechanics and astronautics (heliocentric system).We should mention that there is no such frame of reference that would have been possible for all inertial processes of the system.
