We study mechanical oscillations

The physical world around us is full of movement. It is practically impossible to find at least one physical body that could be considered to be at rest. In addition to the uniformly progressive rectilinear motion, movements along a complex trajectory, motion with acceleration, and the like, we can observe with our own eyes or experience the influence of periodically repeated movements of material objects.

Man has long noticed the distinctive properties and features of oscillatory movements and even learned to use mechanical oscillations for his own purposes. All the processes recurring in time can be called oscillations. Mechanical vibrations are only part of this diverse world of phenomena that occur in almost the same laws. On a clear example of mechanical repetitive movements, it is possible to make basic rules and determine the laws by which electromagnetic, electromechanical and other oscillatory processes occur.

The nature of the appearance of mechanical oscillations lies in the periodic transformation of potential energy into kinetic energy. Describe the example of how the transformation of energy occurs under mechanical vibrations, it is possible, considering a ball suspended on a spring. In a calm state, the force of gravity is balanced by the elasticity of the spring. But it is necessary to deduce the system from the state of equilibrium forcibly, thus provoking motion from the side of the equilibrium point, as potential energy will begin its transformation into kinetic. And that, in turn, from the moment of passage by a ball of zero position will start to be transformed into potential. This process takes place as long as the conditions for the existence of the system are approaching the flawless.

Mathematically ideal are considered oscillations occurring according to the law of the sine or cosine. Such processes are usually called harmonic oscillations. An ideal example of mechanical harmonic oscillations is the motion of a pendulum in an absolutely airless space, when there is no influence of frictional forces. But this is a completely flawless case, to achieve which is technically very problematic.

Mechanical oscillations, despite their duration, sooner or later cease, and the system occupies a position of relative equilibrium. This is due to the waste of energy to overcome the resistance of air, friction and other factors that inevitably lead to an adjustment of the calculations in the transition from ideal to the actual conditions in which the system in question exists.

Irreversibly approaching a deep study and analysis, we come to the need to describe mathematically the mechanical oscillations. The formulas of this process include such quantities as amplitude (A), oscillation frequency (w), initial phase (a). A function of the dependence of the displacement (x) on time (t) in the classical form has the form

X = Acos (wt + a).

It is also worth mentioning the value characterizing mechanical oscillations, called the period (T), which is mathematically determined as

T = 2π / w.

Mechanical vibrations, in addition to clarity of describing the processes of fluctuations of nonmechanical nature, interest us with certain properties that, when properly used, may have some usefulness, and if ignored, lead to significant trouble.

Particular attention must be paid to the phenomenon of a sharp jump in the amplitude for forced oscillations that occur when the frequency of the action of the driving force approaches the frequency of the body's natural vibrations. It is called resonance. Widely used in electronics, in mechanical systems, the phenomenon of resonance is mainly destructive, it must be taken into account when creating the most diverse mechanical structures and systems.

The next manifestation of mechanical vibrations is vibration. Its appearance may not only cause some discomfort, but also bring a resonance. But, in addition to the negative impact, local vibration with a small intensity of manifestation can favorably affect the human body as a whole, improving the functional state of the central nervous system, and even accelerating the healing of wounds , etc.

Among the variants of the manifestation of mechanical oscillations, one can distinguish the phenomenon of sound and ultrasound. The useful properties of these mechanical waves and other manifestations of mechanical oscillations are widely used in the most diverse branches of human life activity.