There are different types of oscillations in physics, characterized by certain parameters. Let's consider their main differences, classification by different factors.
By oscillation is meant a process in which, at regular intervals, the basic characteristics of the motion have the same values.
Periodic called such oscillations, in which the values of the basic quantities are repeated through the same time intervals (oscillation period).
Let us consider the main types of oscillations that exist in fundamental physics.
Free vibrations are called oscillations that occur in a system that is not subject to external variable influences after the initial shock.
An example of free oscillations is a mathematical pendulum.
Those kinds of mechanical oscillations that arise in the system under the action of an external variable force.
The following types of oscillatory movements are distinguished by physical nature:
Types of vibrations in interaction with the environment distinguish several groups.
Forced oscillations appear in the system under the action of an external periodic action. As examples of this type of vibration, one can consider the movement of hands, leaves on trees.
For forced harmonic oscillations, a resonance can occur, at which for equal values of the frequency of the external action and the oscillator with a sharp increase in the amplitude.
Own fluctuations in the system underThe impact of internal forces after it is removed from the equilibrium state. The simplest version of free oscillations is the movement of a load that is suspended on a thread, or attached to a spring.
Автоколебаниями называют виды, при которых у system there is a certain reserve of potential energy, which goes to make oscillations. A distinctive feature of them is the fact that the amplitude is characterized by the properties of the system itself, and not by the original conditions.
For random oscillations, the external load has a random value.
All types of oscillations have certain characteristics, which should be mentioned separately.
Amplitude is the maximum deviation from the equilibrium position, the deviation of the oscillating quantity, measured in meters.
The period is the time of one complete oscillation, through which the characteristics of the system are repeated, is calculated in seconds.
The frequency is determined by the number of oscillations per unit of time, it is inversely proportional to the period of oscillations.
The oscillation phase characterizes the state of the system.
Such types of oscillations occur according to the lawcosine or sinus. Fourier succeeded in establishing that any periodic oscillation can be represented as a sum of harmonic changes by expanding a definite function in a Fourier series.
As an example, we can consider a pendulum having a certain period and a cyclic frequency.
What are the characteristics of such types of oscillations?Physics considers a mathematical pendulum an idealized system, which consists of a material point that is suspended on a weightless inextensible thread, oscillates under the influence of gravity.
These types of oscillations have a certain amount of energy, they are common in nature and technology.
With continuous oscillatory motion, the coordinate of its center of mass changes, and at an alternating current the value of the current and voltage in the circuit changes.
Allocate different types of harmonic oscillations in physical nature: electromagnetic, mechanical, etc.
As the forced fluctuations, the shaking of the vehicle, which moves along an uneven road, appears.
These types of electromagnetic oscillations differ inphysical characteristics. The presence of resistance of the medium and the frictional force lead to attenuation of free oscillations. In the case of forced oscillations, the energy losses are compensated by its additional intake from an external source.
The period of the spring pendulum binds the body mass and the spring stiffness. In the case of a mathematical pendulum, it depends on the length of the filament.
For a known period, one can calculate the natural frequency of the oscillatory system.
In engineering and nature, there are fluctuations withdifferent frequency values. For example, the pendulum, which oscillates in St. Isaac's Cathedral in St. Petersburg, has a frequency of 0.05 Hz, and for atoms it is several million megahertz.
After a certain period of time,attenuation of free oscillations. This is why forced oscillations are used in real practice. They are in demand in a variety of vibrating machines. Vibro-hammer is a shock-vibrating machine, which is designed to drive pipes, piles, and other metal structures into the ground.
Characterization of modes of oscillation assumesanalysis of the basic physical parameters: charge, voltage, amperage. As an elementary system, which is used to observe electromagnetic oscillations, is the oscillatory circuit. It is formed by the serial connection of a coil and a capacitor.
When the circuit is closed, free electromagnetic oscillations arise in it, connected with periodic changes of electric charge on the capacitor and current in the coil.
They are free due to the fact that when they are committed there is no external influence, and only energy that is stored in the circuit itself is used.
If we assume that the resistance of the coil is zero and the oscillation period is taken as T, we can consider one complete oscillation made by the system.
In the absence of external influence, througha certain time interval, there is a damping of the electromagnetic oscillation. The reason for this phenomenon is the gradual discharge of the capacitor, as well as the resistance that the coil actually has.
That's why in the real circuit there aredamped oscillations. Reducing the charge on the capacitor leads to a decrease in the energy value in comparison with its original value. Gradually it will separate out in the form of heat on the connecting wires and coil, the capacitor will be completely discharged, and the electromagnetic oscillation will end.
Любые движения, которые обладают определенной the degree of recurrence, are fluctuations. For example, a mathematical pendulum is characterized by a systematic deviation to both sides of the original vertical position.
For a spring pendulum, one complete oscillation corresponds to its up and down motion from its initial position.
In the electrical circuit, which hascapacitance and inductance, a charge is observed on the capacitor plates. What is the cause of the vibrational movements? The pendulum functions because gravity forces it to return to its original position. In the case of a spring-type model, a similar force is exerted by the elastic force of the spring. Passing the position of equilibrium, the load has a certain speed, therefore, by inertia it moves past the average state.
Electric oscillations can be explained by the potential difference existing between the plates of a charged capacitor. Even with its full discharge, the current does not disappear, and the charge is recharged.
In modern technology, oscillations are used that differ substantially in nature, degree of recurrence, character, and also the "mechanism" of appearance.
Mechanical vibrations make stringsmusical instruments, sea waves, pendulum. Chemical fluctuations associated with a change in the concentration of reacting substances are taken into account when carrying out various interactions.
Electromagnetic oscillations allow the creation of various technical devices, for example, telephone, ultrasonic medical devices.
Fluctuations in the brightness of cepheids are of particular interest in astrophysics, and scientists from different countries are engaged in their study.
All types of fluctuations are closely related to the hugenumber of technical processes and physical phenomena. Their practical significance in aircraft building, construction of ships, construction of residential complexes, electrical engineering, radio electronics, medicine, and fundamental science is great. An example of a typical oscillatory process in physiology is the movement of the heart muscle. Mechanical oscillations are found in organic and inorganic chemistry, meteorology, and also in many other natural sciences.
The first studies of the mathematical pendulum wereconducted in the seventeenth century, and by the end of the nineteenth century, scientists were able to establish the nature of electromagnetic oscillations. The Russian scientist Alexander Popov, who is considered the "father" of radio communication, conducted his experiments precisely on the basis of the theory of electromagnetic oscillations, the results of the investigations of Thomson, Huygens, and Rayleigh. He managed to find a practical application of electromagnetic oscillations, to use them to transmit a radio signal over a long distance.
Academician PNLebedev for many years conducted experiments related to obtaining electromagnetic oscillations of high frequency by means of varying electric fields. Thanks to numerous experiments connected with various types of oscillations, scientists managed to find areas of their optimal use in modern science and technology.
