Man lives in the natural world. You yourself and everything that surrounds you - air, trees, river, sun - these are different objects of nature. Objects of nature are constantly undergoing changes, which are called natural phenomena.
Since ancient times, people have been trying to understand: how and why do various phenomena occur? How do birds fly and why don't they fall? How can a tree float on water and why does it not sink? Some natural phenomena - thunder and lightning, solar and lunar eclipses - frightened people until scientists figured out how and why they occur.
Observing and studying the phenomena occurring in nature, people have found their application in their lives. Watching the flight of birds (Fig. 1), people constructed an airplane (Fig. 2).

Rice. one	Rice. 2

Watching a floating tree, man learned to build ships, conquered the seas and oceans. After studying the way the jellyfish moves (Fig. 3), scientists came up with a rocket engine (Fig. 4). By observing lightning, scientists discovered electricity, without which today people cannot live and work. All sorts of household electrical devices (lighting lamps, televisions, vacuum cleaners) surround us everywhere. Various electric tools (electric drill, electric saw, sewing machine) are used in school workshops and in production.

Scientists divided all physical phenomena into groups (Fig. 6):

Rice. 6

mechanical phenomena- these are phenomena that occur with physical bodies when they move relative to each other (the revolution of the Earth around the Sun, the movement of cars, the swing of a pendulum).
electrical phenomena- these are phenomena that occur during the appearance, existence, movement and interaction of electric charges (electric current, lightning).
Magnetic phenomena- these are phenomena associated with the occurrence of magnetic properties in physical bodies (attraction of iron objects by a magnet, turning the compass needle to the north).
optical phenomena- these are phenomena that occur during the propagation, refraction and reflection of light (reflection of light from a mirror, mirages, the appearance of a shadow).
thermal phenomena- these are phenomena associated with the heating and cooling of physical bodies (boiling a kettle, the formation of fog, the transformation of water into ice).
Atomic Phenomena- these are phenomena that occur when the internal structure of the substance of physical bodies changes (the glow of the Sun and stars, an atomic explosion).
Watch and explain. 1. Give an example of a natural phenomenon. 2. What group of physical phenomena does it belong to? Why? 3. Name the physical bodies that participated in physical phenomena.

In 1979, the Gorky People's University of Scientific and Technical Creativity issued Methodological Materials for its new development "Integrated Method for Searching for New Technical Solutions". We plan to acquaint the readers of the site with this interesting development, which in many ways was far ahead of its time. But today we suggest that you familiarize yourself with a fragment of the third part of the methodological materials, published under the name "Arrays of information". The list of physical effects proposed in it includes only 127 positions. Now specialized computer programs offer more detailed versions of physical effects indexes, but for a user who is still "not covered" by software support, the table of applications of physical effects created in Gorky is of interest. Its practical use lies in the fact that at the input the solver had to indicate which function from those listed in the table he wants to provide and which type of energy he plans to use (as they would say now - indicate resources). The numbers in the cells of the table are the numbers of physical effects in the list. Each physical effect is provided with references to literary sources (unfortunately, almost all of them are currently bibliographic rarities).
The work was carried out by a team, which included teachers from the Gorky People's University: M.I. Weinerman, B.I. Goldovsky, V.P. Gorbunov, L.A. Zapolyansky, V.T. Korelov, V.G. Kryazhev, A.V. Mikhailov, A.P. Sokhin, Yu.N. Shelomok. The material offered to the reader's attention is compact, and therefore can be used as a handout in the classroom in public schools of technical creativity.
Editor

List of physical effects and phenomena

Gorky People's University of Scientific and Technical Creativity
Gorky, 1979

N	Name of a physical effect or phenomenon	Brief description of the essence of the physical effect or phenomenon	Typical functions (actions) performed (see Table 1)	Literature
1	2	3	4	5
1	Inertia	The movement of bodies after the termination of the action of forces. A body rotating or moving by inertia can accumulate mechanical energy, produce a force effect	5, 6, 7, 8, 9, 11, 13, 14, 15, 21	42, 82, 144
2	gravity	force interaction of masses at a distance, as a result of which bodies can move, approaching each other	5, 6, 7, 8, 9, 11, 13, 14, 15	127, 128, 144
3	Gyroscopic effect	Bodies rotating at high speed are able to maintain the same position of their axis of rotation. A force from the side to change the direction of the axis of rotation leads to a precession of the gyroscope proportional to the force	10, 14	96, 106
4	Friction	The force arising from the relative movement of two bodies in contact in the plane of their contact. Overcoming this force leads to the release of heat, light, wear	2, 5, 6, 7, 9, 19, 20	31, 114, 47, 6, 75, 144
5	Replacing static friction with friction of motion	When the rubbing surfaces vibrate, the friction force decreases	12	144
6	Effect of wearlessness (Kragelsky and Garkunov)	A pair of steel-bronze with glycerin lubricant practically does not wear out	12	75
7	Johnson-Rabeck effect	Heating of rubbing metal-semiconductor surfaces increases the friction force	2, 20	144
8	Deformation	Reversible or irreversible (elastic or plastic deformation) change in the mutual position of body points under the action of mechanical forces, electrical, magnetic, gravitational and thermal fields, accompanied by the release of heat, sound, light	4, 13, 18, 22	11, 129
9	Poiting effect	Elastic elongation and increase in the volume of steel and copper wires when they are twisted. The properties of the material do not change.	11, 18	132
10	Relationship between deformation and electrical conductivity	When a metal passes into the superconducting state, its plasticity increases.	22	65, 66
11	Electroplastic effect	Increase in ductility and decrease in brittleness of the metal under the action of high-density direct electric current or pulsed current	22	119
12	Bauschinger effect	Reducing the resistance to initial plastic deformations when the sign of the load changes	22	102
13	Alexandrov effect	With an increase in the ratio of the masses of elastically colliding bodies, the energy transfer coefficient increases only to a critical value determined by the properties and configuration of the bodies	15	2
14	Alloys with memory	Deformed with the help of mechanical forces, parts made of some alloys (titanium-nickel, etc.) after heating, restore exactly their original shape and are capable of creating significant force effects.	1, 4, 11, 14, 18, 22	74
15	explosion phenomenon	Ignition of substances due to their instantaneous chemical decomposition and the formation of highly heated gases, accompanied by a strong sound, the release of significant energy (mechanical, thermal), light flash	2, 4, 11, 13, 15, 18, 22	129
16	thermal expansion	Change in the size of bodies under the influence of a thermal field (during heating and cooling). Can be accompanied by significant effort	5, 10, 11, 18	128,144
17	Phase transitions of the first kind	Change in the density of the aggregate state of substances at a certain temperature, accompanied by release or absorption	1, 2, 3, 9, 11, 14, 22	129, 144, 33
18	Phase transitions of the second kind	An abrupt change in heat capacity, thermal conductivity, magnetic properties, fluidity (superfluidity), plasticity (superplasticity), electrical conductivity (superconductivity) when a certain temperature is reached and without energy exchange	1, 3, 22	33, 129, 144
19	Capillarity	Spontaneous flow of liquid under the action of capillary forces in capillaries and semi-open channels (microcracks and scratches)	6, 9	122, 94, 144, 129, 82
20	Laminar and turbulence	Laminarity is an ordered movement of a viscous liquid (or gas) without interlayer mixing with a flow rate decreasing from the center of the pipe to the walls. Turbulence - the chaotic movement of a liquid (or gas) with random movement of particles along complex trajectories and an almost constant flow velocity over the cross section	5, 6, 11, 12, 15	128, 129, 144
21	Surface tension of liquids	Surface tension forces due to the presence of surface energy tend to reduce the interface	6, 19, 20	82, 94, 129, 144
22	wetting	Physical and chemical interaction of a liquid with a solid. The character depends on the properties of the interacting substances	19	144, 129, 128
23	Autophobic effect	When a liquid with low tension and a high-energy solid comes into contact, first complete wetting occurs, then the liquid collects into a drop, and a strong molecular layer of liquid remains on the surface of the solid	19, 20	144, 129, 128
24	Ultrasonic capillary effect	Increasing the rate and height of liquid rise in capillaries under the action of ultrasound	6	14, 7, 134
25	Thermocapillary effect	The dependence of the liquid spreading rate on the uneven heating of its layer. The effect depends on the purity of the liquid, on its composition.	1, 6, 19	94, 129, 144
26	Electrocapillary effect	Dependence of the surface tension at the interface between electrodes and electrolyte solutions or ionic melts on the electric potential	6, 16, 19	76, 94
27	Sorption	The process of spontaneous condensation of a dissolved or vaporous substance (gas) on the surface of a solid or liquid. With a small penetration of the sorbent substance into the sorbent, adsorption occurs, with a deep penetration, absorption occurs. The process is accompanied by heat transfer	1, 2, 20	1, 27, 28, 100, 30, 43, 129, 103
28	Diffusion	The process of equalizing the concentration of each component in the entire volume of a gas or liquid mixture. The rate of diffusion in gases increases with decreasing pressure and increasing temperature	8, 9, 20, 22	32, 44, 57, 82, 109, 129, 144
29	Dufort effect	The occurrence of a temperature difference during diffusion mixing of gases	2	129, 144
30	Osmosis	Diffusion through a semi-permeable septum. Accompanied by the creation of osmotic pressure	6, 9, 11	15
31	Heat and mass exchange	Heat transfer. May be accompanied by agitation of the mass or be caused by movement of the mass	2, 7, 15	23
32	Law of Archimedes	Lift force acting on a body immersed in a liquid or gas	5, 10, 11	82, 131, 144
33	Pascal's law	Pressure in liquids or gases is transmitted uniformly in all directions	11	82, 131, 136, 144
34	Bernoulli's law	Total pressure constancy in steady laminar flow	5, 6	59
35	Viscoelectric effect	Increase in the viscosity of a polar non-conductive liquid when flowing between the capacitor plates	6, 10, 16, 22	129, 144
36	Toms effect	Reduced friction between turbulent flow and pipeline when a polymer additive is introduced into the flow	6, 12, 20	86
37	Coanda effect	Deviation of the jet of liquid flowing from the nozzle towards the wall. Sometimes there is "sticking" of the liquid	6	129
38	Magnus effect	The emergence of a force acting on a cylinder rotating in the oncoming flow, perpendicular to the flow and generatrices of the cylinder	5,11	129, 144
39	Joule-Thomson effect (choke effect)	Change in gas temperature as it flows through a porous partition, diaphragm or valve (without exchange with the environment)	2, 6	8, 82, 87
40	Water hammer	Rapid shutdown of a pipeline with a moving liquid causes a sharp increase in pressure, propagating in the form of a shock wave, and the appearance of cavitation	11, 13, 15	5, 56, 89
41	Electrohydraulic shock (Yutkin effect)	Water hammer caused by pulsed electrical discharge	11, 13, 15	143
42	Hydrodynamic cavitation	The formation of discontinuities in a fast flow of a continuous liquid as a result of a local decrease in pressure, causing the destruction of the object. Accompanied by sound	13, 18, 26	98, 104
43	acoustic cavitation	Cavitation due to the passage of acoustic waves	8, 13, 18, 26	98, 104, 105
44	sonoluminescence	Weak glow of the bubble at the moment of its cavitation collapse	4	104, 105, 98
45	Free (mechanical) vibrations	Natural damped oscillations when the system is taken out of equilibrium. In the presence of internal energy, oscillations become undamped (self-oscillations)	1, 8, 12, 17, 21	20, 144, 129, 20, 38
46	Forced vibrations	Oscillations of the year by the action of a periodic force, usually external	8, 12, 17	120
47	Acoustic paramagnetic resonance	Resonance absorption of sound by a substance, depending on the composition and properties of the substance	21	37
48	Resonance	A sharp increase in the amplitude of oscillations when forced and natural frequencies coincide	5, 9, 13, 21	20, 120
49	Acoustic vibrations	Propagation of sound waves in a medium. The nature of the impact depends on the frequency and intensity of the oscillations. Main purpose - force impact	5, 6, 7, 11, 17, 21	38, 120
50	Reverberation	Aftersound due to the transition to a certain point of delayed reflected or scattered sound waves	4, 17, 21	120, 38
51	Ultrasound	Longitudinal vibrations in gases, liquids and solids in the frequency range 20x103-109Hz. Beam propagation with effects of reflection, focusing, shadowing with the possibility of transferring high energy density used for force and thermal effects	2, 4, 6, 7, 8, 9, 13, 15, 17, 20, 21, 22, 24, 26	7, 10, 14, 16, 90, 107, 133
52	wave motion	energy transfer without matter transfer in the form of a perturbation propagating at a finite speed	6, 15	61, 120, 129
53	Doppler-Fizo effect	Changing the frequency of oscillations with the mutual displacement of the source and receiver of oscillations	4	129, 144
54	standing waves	At a certain phase shift, the direct and reflected waves add up to a standing wave with a characteristic arrangement of perturbation maxima and minima (nodes and antinodes). There is no energy transfer through nodes, and interconversion of kinetic and potential energy is observed between neighboring nodes. The force effect of a standing wave is capable of creating an appropriate structure	9, 23	120, 129
55	Polarization	Violation of axial symmetry of a transverse wave relative to the direction of propagation of this wave. Polarization is caused by: lack of axial symmetry of the emitter, or reflection and refraction at the boundaries of different media, or propagation in an anisotropic medium	4, 16, 19, 21, 22, 23, 24	53, 22, 138
56	Diffraction	Wave bending around an obstacle. Depends on obstacle size and wavelength	17	83, 128, 144
57	Interference	Strengthening and weakening of waves at certain points in space, arising from the superposition of two or more waves	4, 19, 23	83, 128, 144
58	moiré effect	The appearance of a pattern when two systems of equidistant parallel lines intersect at a small angle. A small change in the angle of rotation leads to a significant change in the distance between the elements of the pattern.	19, 23	91, 140
59	Coulomb's law	Attraction of unlike and repulsion of like electrically charged bodies	5, 7, 16	66, 88, 124
60	Induced charges	The appearance of charges on a conductor under the influence of an electric field	16	35, 66, 110
61	Interaction of bodies with fields	A change in the shape of bodies leads to a change in the configuration of the generated electric and magnetic fields. This can control the forces acting on charged particles placed in such fields	25	66, 88, 95, 121, 124
62	Retraction of the dielectric between the plates of the capacitor	With the partial introduction of a dielectric between the plates of the capacitor, its retraction is observed	5, 6, 7, 10, 16	66, 110
63	Conductivity	Movement of free carriers under the action of an electric field. Depends on the temperature, density and purity of the substance, its state of aggregation, external influence of forces causing deformation, on hydrostatic pressure. In the absence of free carriers, the substance is an insulator and is called a dielectric. When thermally excited, it becomes a semiconductor	1, 16, 17, 19, 21, 25	123
64	Superconductivity	A significant increase in the conductivity of some metals and alloys at certain temperatures, magnetic fields and current densities	1, 15, 25	3, 24, 34, 77
65	Joule-Lenz law	The release of thermal energy during the passage of an electric current. The value is inversely proportional to the conductivity of the material	2	129, 88
66	Ionization	The appearance of free charge carriers in substances under the influence of external factors (electromagnetic, electric or thermal fields, discharges in gases, irradiation with X-rays or a stream of electrons, alpha particles, during the destruction of bodies)	6, 7, 22	129, 144
67	Eddy currents (Foucault currents)	In a massive non-ferromagnetic plate placed in a changing magnetic field perpendicular to its lines, circular induction currents flow. In this case, the plate heats up and is pushed out of the field	2, 5, 6, 10, 11, 21, 24	50, 101
68	Brake without static friction	A heavy metal plate oscillating between the poles of an electromagnet "sticks" when the direct current is turned on and stops	10	29, 35
69	Conductor with current in a magnetic field	The Lorentz force acts on the electrons, which through the ions transfer the force to the crystal lattice. As a result, the conductor is pushed out of the magnetic field	5, 6, 11	66, 128
70	conductor moving in a magnetic field	When a conductor moves in a magnetic field, an electric current begins to flow in it.	4, 17, 25	29, 128
71	Mutual induction	An alternating current in one of two adjacent circuits causes the appearance of an induction emf in the other	14, 15, 25	128
72	Interaction of conductors with the current of moving electric charges	Conductors with current are pulled towards each other or repelled. Moving electric charges interact similarly. The nature of the interaction depends on the shape of the conductors	5, 6, 7	128
73	EMF induction	When the magnetic field or its movement changes in a closed conductor, an induction emf arises. The direction of the inductive current gives a field that prevents a change in the magnetic flux that causes induction	24	128
74	Surface effect (skin effect)	High frequency currents go only along the surface layer of the conductor	2	144
75	Electromagnetic field	Mutual induction of electric and magnetic fields is the propagation (radio waves, electromagnetic waves, light, x-rays and gamma rays). An electric field can also serve as its source. A special case of the electromagnetic field is light radiation (visible, ultraviolet and infrared). The thermal field can also serve as its source. The electromagnetic field is detected by the thermal effect, electrical action, light pressure, activation of chemical reactions	1, 2, 4, 5, 6, 7, 11, 15, 17, 19, 20, 21, 22, 26	48, 60, 83, 35
76	Charge in a magnetic field	A charge moving in a magnetic field is subject to the Lorentz force. Under the action of this force, the movement of the charge occurs in a circle or spiral	5, 6, 7, 11	66, 29
77	Electrorheological effect	Rapid reversible increase in the viscosity of non-aqueous disperse systems in strong electric fields	5, 6, 16, 22	142
78	Dielectric in a magnetic field	In a dielectric placed in an electromagnetic field, part of the energy is converted into thermal	2	29
79	breakdown of dielectrics	The drop in electrical resistance and thermal destruction of the material due to the heating of the dielectric section under the action of a strong electric field	13, 16, 22	129, 144
80	Electrostriction	Elastic reversible increase in body size in an electric field of any sign	5, 11, 16, 18	66
81	Piezoelectric effect	Formation of charges on the surface of a solid body under the influence of mechanical stresses	4, 14, 15, 25	80, 144
82	Reverse piezo effect	Elastic deformation of a rigid body under the action of an electric field, depending on the sign of the field	5, 11, 16, 18	80
83	Electro-caloric effect	Change in the temperature of a pyroelectric when it is introduced into an electric field	2, 15, 16	129
84	Electrification	The appearance of electric charges on the surface of substances. It can also be called in the absence of an external electric field (for pyroelectrics and ferroelectrics when the temperature changes). When a substance is exposed to a strong electric field with cooling or lighting, electrets are obtained that create an electric field around them.	1, 16	116, 66, 35, 55, 124, 70, 88, 36, 41, 110, 121
85	Magnetization	Orientation of intrinsic magnetic moments of substances in an external magnetic field. According to the degree of magnetization, substances are divided into paramagnets and ferromagnets. For permanent magnets, the magnetic field remains after removing the external electrical and magnetic properties	1, 3, 4, 5, 6, 8, 10, 11, 22, 23	78, 73, 29, 35
86	Effect of temperature on electrical and magnetic properties	The electrical and magnetic properties of substances near a certain temperature (Curie point) change dramatically. Above the Curie point, a ferromagnet transforms into a paramagnet. Ferroelectrics have two Curie points at which either magnetic or electrical anomalies are observed. Antiferromagnets lose their properties at a temperature called the Neel point	1, 3, 16, 21, 22, 24, 25	78, 116, 66, 51, 29
87	magnetoelectric effect	In ferroferromagnets, when a magnetic (electric) field is applied, a change in the electric (magnetic) permeability is observed	22, 24, 25	29, 51
88	Hopkins effect	An increase in magnetic susceptibility as the Curie temperature is approached	1, 21, 22, 24	29
89	Barchhausen effect	Stepwise behavior of the magnetization curve of a sample near the Curie point with a change in temperature, elastic stresses, or an external magnetic field	1, 21, 22, 24	29
90	Liquids solidifying in a magnetic field	viscous liquids (oils) mixed with ferromagnetic particles harden when placed in a magnetic field	10, 15, 22	139
91	Piezo magnetism	Occurrence of a magnetic moment upon imposition of elastic stresses	25	29, 129, 144
92	Magneto-caloric effect	The change in temperature of a magnet during its magnetization. For paramagnets, increasing the field increases the temperature	2, 22, 24	29, 129, 144
93	Magnetostriction	Changing the size of bodies when changing their magnetization (volumetric or linear), the object depends on temperature	5, 11, 18, 24	13, 29
94	thermostriction	Magnetostrictive deformation during heating of bodies in the absence of a magnetic field	1, 24	13, 29
95	Einstein and de Haas effect	Magnetization of a magnet causes it to rotate, and rotation causes magnetization	5, 6, 22, 24	29
96	Ferromagnetic resonance	Selective (by frequency) absorption of electromagnetic field energy. The frequency changes depending on the intensity of the field and when the temperature changes.	1, 21	29, 51
97	Contact potential difference (Volta's law)	The occurrence of a potential difference when two different metals are in contact. The value depends on the chemical composition of the materials and their temperature	19, 25	60
98	triboelectricity	Electrization of bodies during friction. The magnitude and sign of the charge are determined by the state of the surfaces, their composition, density and dielectric constant	7, 9, 19, 21, 25	6, 47, 144
99	Seebeck effect	The emergence of thermoEMF in a circuit of dissimilar metals under the condition of different temperatures at the points of contact. When homogeneous metals are in contact, the effect occurs when one of the metals is compressed by all-round pressure or when it is saturated with a magnetic field. The other conductor is in normal conditions.	19, 25	64
100	Peltier effect	Emission or absorption of heat (except for Joule heat) during the passage of current through a junction of dissimilar metals, depending on the direction of the current	2	64
101	Thomson phenomenon	Emission or absorption of heat (excess over Joule) during the passage of current through an unevenly heated homogeneous conductor or semiconductor	2	36
102	hall effect	The occurrence of an electric field in a direction perpendicular to the direction of the magnetic field and the direction of the current. In ferromagnets, the Hall coefficient reaches a maximum at the Curie point and then decreases	16, 21, 24	62, 71
103	Ettingshausen effect	The occurrence of a temperature difference in the direction perpendicular to the magnetic field and current	2, 16, 22, 24	129
104	Thomson effect	Change in the conductivity of a ferromanite conductor in a strong magnetic field	22, 24	129
105	Nernst effect	The appearance of an electric field during the transverse magnetization of the conductor perpendicular to the direction of the magnetic field and the temperature gradient	24, 25	129
106	Electrical discharges in gases	The occurrence of an electric current in a gas as a result of its ionization and under the action of an electric field. External manifestations and characteristics of discharges depend on control factors (gas composition and pressure, space configuration, electric field frequency, current strength)	2, 16, 19, 20, 26	123, 84, 67, 108, 97, 39, 115, 40, 4
107	Electroosmosis	The movement of liquids or gases through capillaries, solid porous diaphragms and membranes, and through the forces of very small particles under the influence of an external electric field	9, 16	76
108	flow potential	The occurrence of a potential difference between the ends of capillaries, as well as between opposite surfaces of a diaphragm, membrane or other porous medium when liquid is forced through them	4, 25	94
109	electrophoresis	Movement of solid particles, gas bubbles, liquid droplets, as well as suspended colloidal particles in a liquid or gaseous medium under the action of an external electric field	6, 7, 8, 9	76
110	Sedimentation potential	The occurrence of a potential difference in a liquid as a result of the movement of particles caused by forces of a non-electric nature (settlement of particles, etc.)	21, 25	76
111	liquid crystals	A liquid with elongated molecules tends to become cloudy in spots when exposed to an electric field and change color at different temperatures and viewing angles	1, 16	137
112	Light dispersion	Dependence of the absolute refractive index on the radiation wavelength	21	83, 12, 46, 111, 125
113	Holography	Obtaining volumetric images by illuminating an object with coherent light and photographing the interference pattern of the interaction of the light scattered by the object with the coherent radiation of the source	4, 19, 23	9, 45, 118, 95, 72, 130
114	Reflection and refraction	When a parallel beam of light is incident on a smooth interface between two isotropic media, part of the light is reflected back, while the other part, being refracted, passes into the second medium	4,	21
115	Absorption and scattering of light	When light passes through matter, its energy is absorbed. Part goes to reemission, the rest of the energy goes into other forms (heat). Part of the re-radiated energy propagates in different directions and forms scattered light	15, 17, 19, 21	17, 52, 58
116	Light emission. Spectral analysis	A quantum system (atom, molecule) in an excited state radiates excess energy in the form of a portion of electromagnetic radiation. The atoms of each substance have a failure structure of radiative transitions that can be registered by optical methods.	1, 4, 17, 21	17, 52, 58
117	Optical quantum generators (lasers)	Amplification of electromagnetic waves due to their passage through a medium with population inversion. Laser radiation is coherent, monochromatic, with a high energy concentration in the beam and low divergence	2, 11, 13, 15, 17, 19, 20, 25, 26	85, 126, 135
118	The phenomenon of total internal reflection	All the energy of a light wave incident on the interface of transparent media from the side of the optically denser medium is completely reflected into the same medium	1, 15, 21	83
119	Luminescence, luminescence polarization	Radiation, excess under thermal and having a duration exceeding the period of light oscillations. Luminescence continues for some time after the termination of excitation (electromagnetic radiation, energy of an accelerated flow of particles, energy of chemical reactions, mechanical energy)	4, 14, 16, 19, 21, 24	19, 25, 92, 117, 68, 113
120	Quenching and stimulation of luminescence	Exposure to another type of energy, in addition to exciting luminescence, can either stimulate or extinguish luminescence. Control factors: thermal field, electric and electromagnetic fields (IR light), pressure; humidity, the presence of certain gases	1, 16, 24	19
121	Optical anisotropy	difference in the optical properties of substances in different directions, depending on their structure and temperature	1, 21, 22	83
122	double refraction	On the. At the interface between anisotropic transparent bodies, light is split into two mutually perpendicular polarized beams with different propagation velocities in the medium	21	54, 83, 138, 69, 48
123	Maxwell effect	Occurrence of birefringence in a liquid flow. Determined by the action of hydrodynamic forces, flow velocity gradient, wall friction	4, 17	21
124	Kerr effect	Occurrence of optical anisotropy in isotropic substances under the influence of electric or magnetic fields	16, 21, 22, 24	99, 26, 53
125	Pockels effect	Occurrence of optical anisotropy under the action of an electric field in the direction of light propagation. Weakly dependent on temperature	16, 21, 22	129
126	Faraday effect	Rotation of the plane of polarization of light when passing through a substance placed in a magnetic field	21, 22, 24	52, 63, 69
127	Natural optical activity	The ability of a substance to rotate the plane of polarization of light passing through it	17, 21	54, 83, 138

Physical effects selection table

References to the array of physical effects and phenomena

1. Adam N.K. Physics and chemistry of surfaces. M., 1947

2. Alexandrov E.A. JTF. 36, No. 4, 1954

3. Alievsky B.D. Application of cryogenic technology and superconductivity in electrical machines and apparatuses. M., Informstandardelectro, 1967

4. Aronov M.A., Kolechitsky E.S., Larionov V.P., Minein V.R., Sergeev Yu.G. Electric discharges in air at a high frequency voltage, M., Energia, 1969

5. Aronovich G.V. etc. Hydraulic shock and surge tanks. M., Nauka, 1968

6. Akhmatov A.S. Molecular physics of boundary friction. M., 1963

7. Babikov O.I. Ultrasound and its application in industry. FM, 1958"

8. Bazarov I.P. Thermodynamics. M., 1961

9. Buters J. Holography and its application. M., Energy, 1977

10. Baulin I. Beyond the barrier of hearing. M., Knowledge, 1971

11. Bezhukhov N.I. Theory of elasticity and plasticity. M., 1953

12. Bellamy L. Infrared spectra of molecules. Moscow, 1957

13. Belov K.P. magnetic transformations. M., 1959

14. Bergman L. Ultrasound and its application in technology. M., 1957

15. Bladergren V. Physical chemistry in medicine and biology. M., 1951

16. Borisov Yu.Ya., Makarov L.O. Ultrasound in the technology of the present and the future. Academy of Sciences of the USSR, M., 1960

17. Born M. Atomic physics. M., 1965

18. Brüning G. Physics and application of secondary electron emission

19. Vavilov S.I. About "hot" and "cold" light. M., Knowledge, 1959

20. Weinberg D.V., Pisarenko G.S. Mechanical vibrations and their role in technology. M., 1958

21. Weisberger A. Physical methods in organic chemistry. T.

22. Vasiliev B.I. Optics of polarizing devices. M., 1969

23. Vasiliev L.L., Konev S.V. Heat transfer tubes. Minsk, Science and technology, 1972

24. Venikov V.A., Zuev E.N., Okolotin B.C. Superconductivity in energy. M., Energy, 1972

25. Vereshchagin I.K. Electroluminescence of crystals. M., Nauka, 1974

26. Volkenstein M.V. Molecular Optics, 1951

27. Volkenstein F.F. Semiconductors as catalysts for chemical reactions. M., Knowledge, 1974

28. F. F. Volkenshtein, Radical recombination luminescence of semiconductors. M., Nauka, 1976

29. Vonsovsky S.V. Magnetism. M., Nauka, 1971

30. Voronchev T.A., Sobolev V.D. Physical foundations of electrovacuum technology. M., 1967

31. Garkunov D.N. Selective transfer in friction units. M., Transport, 1969

32. Geguzin Ya.E. Essays on diffusion in crystals. M., Nauka, 1974

33. Geilikman B.T. Statistical physics of phase transitions. M., 1954

34. Ginzburg V.L. The problem of high-temperature superconductivity. Collection "The Future of Science" M., Znanie, 1969

35. Govorkov V.A. Electric and magnetic fields. M., Energy, 1968

36. Goldeliy G. Application of thermoelectricity. M., FM, 1963

37. Goldansky V.I. Mesbauer effect and its

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57. Zayt V. Diffusion in metals. M., 1958

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75. Kragelsky I.V. Friction and wear. M., Mashinostroenie, 1968

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We often take for granted everything that happens to us on earth, but every minute our lives are controlled by many forces. There are a surprising number of unusual, paradoxical, or self-explanatory physical laws in the world that we encounter every day. In an entertaining exploration of physical phenomena that everyone should know, we'll talk about common occurrences that many people consider a mystery, strange forces that we can't understand, and how science fiction can become reality through the manipulation of light.

10. Cold wind effect

Our perception of temperature is quite subjective. Humidity, individual physiology, and even our mood can change our perception of hot and cold temperatures. The same thing happens with the wind: the temperature we feel is not real. The air that directly surrounds the human body serves as a kind of air cloak. This insulating air cushion keeps you warm. When the wind blows on you, this air cushion is blown off and you begin to feel the actual temperature, which is much colder. The cool wind effect only affects objects that generate heat.

9. The faster you drive, the stronger the impact.

People tend to think in a linear way, mostly based on the principles of observation; if one drop of rain weighs 50 milligrams, two drops should weigh about 100 milligrams. However, the forces that control the universe often show us a different result related to the distribution of forces. An object moving at a speed of 40 kilometers per hour will crash into a wall with a certain force. If you double the speed of an object to 80 kilometers per hour, the impact force will increase not two, but four times. This law explains why highway crashes are much more destructive than urban crashes.

8. Orbit is just a constant free fall.

Satellites appear as a notable recent addition to the stars, but we rarely think about the concept of "orbit". We know in general that objects move around planets or large celestial bodies and never fall. But the reason for the emergence of orbits is surprisingly paradoxical. If an object is dropped, it falls to the surface. However, if it is high enough and moving at a fast enough speed, it will deflect off the ground in an arc. The same effect prevents the earth from colliding with the sun.

7. Heat causes freezing.

Water is the most important liquid on earth. This is the most mysterious and paradoxical compound in nature. One of the little-known properties of water is, for example, that warm water freezes faster than cold water. It is not yet fully understood how this happens, but this phenomenon, known as the Mpemba paradox, was discovered by Aristotle about 3,000 years ago. But why exactly this happens is still a mystery.

6. Air pressure.

At the moment, you are affected by air pressure equal to about 1000 kilograms, the same weight as a small car. This is due to the fact that the atmosphere itself is quite heavy, and a person at the bottom of the ocean experiences a pressure equal to 2.3 kg per square centimeter. Our body can withstand such pressure, and it cannot crush us. However, airtight objects, such as plastic bottles, thrown from very high altitudes return to the ground in a crushed state.

5. Metallic hydrogen.

Hydrogen is the first element in the periodic table, making it the simplest element in the universe. Its atomic number is 1, which means it has 1 proton, 1 electron, and no neutrons. Although hydrogen is known as a gas, it may exhibit some of the properties of metals rather than gases. Hydrogen is located on the periodic table just above sodium, a volatile metal that is part of the composition of table salt. Physicists have long understood that hydrogen behaves like a metal under high pressure, like the one found in stars and in the core of gas giant planets. Trying to make such a bond on earth is a lot of work, but some scientists believe they have already created small ones by applying pressure to diamond crystals.

4. Coriolis effect.

Due to the rather large size of the planet, a person does not feel its movement. However, the clockwise movement of the Earth causes objects traveling in the northern hemisphere to move slightly clockwise as well. This phenomenon is known as the Coriolis effect. Since the surface of the Earth is moving at a certain speed with respect to the atmosphere, the difference between the rotation of the Earth and the movement of the atmosphere causes an object moving north to pick up the energy of the Earth's rotation and begin to deviate to the east. The opposite phenomenon is observed in the southern hemisphere. As a result, navigation systems must take into account the Coriolis force to avoid yaw.

3. Doppler effect.

Sound may be an independent phenomenon, but the perception of sound waves depends on speed. Austrian physicist Christian Doppler discovered that when a moving object, such as a siren, emits sound waves, they accumulate in front of the object and scatter behind it. This phenomenon, known as the Doppler effect, causes the sound of an approaching object to become a pitch higher due to the shortening of the sound wavelengths. After the object passes by, the closing sound waves lengthen and, accordingly, become lower tones.

2. Evaporation.

It would be logical to assume that chemicals in the process of transition from a solid state to a gaseous state must pass through a liquid state. However, water is able to immediately transform from a solid to a gas under certain circumstances. Sublimation, or evaporation, can cause glaciers to disappear under the influence of the sun, which turns the ice into steam. In the same way, metals such as arsenic can go into a gaseous state when heated, releasing toxic gases in the process. Water can evaporate below its melting point when exposed to a heat source.

1.Disguised devices.

Rapidly advancing technology is turning science fiction plots into scientific fact. We can see objects when light is reflected off of them at different wavelengths. Scientists have put forward the theory that objects can be considered invisible under certain exposure to light. If the light around an object can be diffused, it becomes invisible to the human eye. AT recent times this theory became a reality when scientists invented a transparent hexagonal prism that diffused light around an object placed inside. When placed in an aquarium, the prism made the goldfish that swam there invisible, and on the ground, livestock disappeared from view. This cloaking effect works on the same principles as aircraft that cannot be detected by radar.

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About the world around. In addition to the usual curiosity, this was due to practical needs. After all, for example, if you know how to raise
and move heavy stones, you will be able to erect strong walls and build a house in which it is more convenient to live than in a cave or a dugout. And if you learn to smelt metals from ores and make plows, scythes, axes, weapons, etc., you will be able to better plow the field and get a higher harvest, and in case of danger you will be able to protect your land.

In ancient times, there was only one science - it combined all the knowledge about nature that mankind had accumulated by that time. Today this science is called natural science.

Learn about physical science

Another example of an electromagnetic field is light. You will get acquainted with some properties of light in the study of section 3.

3. Recall physical phenomena

The matter around us is constantly changing. Some bodies move relative to each other, some of them collide and, possibly, are destroyed, others are formed from some bodies ... The list of such changes can go on and on - it was not for nothing that the philosopher Heraclitus remarked in ancient times: "Everything flows, everything changes." Changes in the world around us, that is, in nature, scientists call a special term - phenomena.

Rice. 1.5. Examples of natural phenomena

Rice. 1.6. A complex natural phenomenon - a thunderstorm can be represented as a combination of a number of physical phenomena

Sunrise and sunset, an avalanche, a volcanic eruption, a horse running, a panther jumping are all examples of natural phenomena (Figure 1.5).

To better understand complex natural phenomena, scientists divide them into a set of physical phenomena - phenomena that can be described using physical laws.

On fig. 1.6 shows a set of physical phenomena that form a complex natural phenomenon - a thunderstorm. So, lightning - a huge electric discharge - is an electromagnetic phenomenon. If lightning hits a tree, it will flare up and begin to release heat - physicists in this case speak of a thermal phenomenon. The roar of thunder and the crackle of burning wood are sound phenomena.

Examples of some physical phenomena are given in the table. Take a look at the first row of the table, for example. What can be in common between the flight of a rocket, the fall of a stone and the rotation of an entire planet? The answer is simple. All the examples of phenomena given in this line are described by the same laws - the laws of mechanical motion. With the help of these laws, it is possible to calculate the coordinates of any moving body (whether it be a stone, a rocket or a planet) at any point in time that interests us.

Rice. 1.7 Examples of electromagnetic phenomena

Each of you, taking off your sweater or combing your hair with a plastic comb, probably paid attention to the tiny sparks that appear at the same time. Both these sparks and the mighty discharge of lightning refer to the same electromagnetic phenomena and, accordingly, obey the same laws. Therefore, to study electromagnetic phenomena, you should not wait for a thunderstorm. It is enough to study how safe sparks behave in order to understand what to expect from lightning and how to avoid possible danger. For the first time such studies were carried out by the American scientist B. Franklin (1706-1790), who invented an effective means of protection against a lightning discharge - a lightning rod.

By studying physical phenomena separately, scientists establish their relationship. Thus, a lightning discharge (electromagnetic phenomenon) is necessarily accompanied by a significant temperature increase in the lightning channel (thermal phenomenon). The study of these phenomena in their interrelation allowed not only to better understand the natural phenomenon - a thunderstorm, but also to find a way for the practical application of electromagnetic and thermal phenomena. Surely each of you, passing by the construction site, saw workers in protective masks and blinding flashes of electric welding. Electric welding (a method of connecting metal parts using an electric discharge) is an example of the practical use of scientific research.

4. Determine what physics studies

Now that you have learned what matter and physical phenomena are, it's time to define what is the subject of study of physics. This science studies: the structure and properties of matter; physical phenomena and their interrelation.

• summing up

The world around us is made up of matter. There are two types of matter: the substance of which all physical bodies are composed, and the field.

The world around us is constantly changing. These changes are called phenomena. Thermal, light, mechanical, sound, electromagnetic phenomena are all examples of physical phenomena.

The subject of physics is the structure and properties of matter, physical phenomena and their interrelation.

• test questions

What does physics study? Give examples of physical phenomena. Can events that occur in a dream or in the imagination be considered physical phenomena? 4. What substances do the following bodies consist of: a textbook, a pencil, a soccer ball, a glass, a car? What physical bodies can consist of glass, metal, wood, plastic?

Physics. Grade 7: Textbook / F. Ya. Bozhinova, N. M. Kiryukhin, E. A. Kiryukhina. - X .: Publishing house "Ranok", 2007. - 192 p.: ill.

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We are surrounded by an infinitely diverse world of substances and phenomena.

It is constantly changing.

Any changes that occur to bodies are called phenomena. The birth of stars, the change of day and night, the melting of ice, the swelling of buds on trees, the flashing of lightning during a thunderstorm, and so on - all these are natural phenomena.

physical phenomena

Recall that bodies are made up of substances. Note that in some phenomena the substances of bodies do not change, while in others they change. For example, if you tear a piece of paper in half, then, despite the changes that have occurred, the paper will remain paper. If the paper is burned, it will turn into ashes and smoke.

Phenomena in which the size, shape of bodies, the state of substances can change, but substances remain the same, do not change into others, are called physical phenomena(evaporation of water, the glow of an electric light bulb, the sound of the strings of a musical instrument, etc.).

Physical phenomena are extremely diverse. Among them are distinguished mechanical, thermal, electrical, lighting and etc.

Let's remember how clouds float across the sky, an airplane flies, a car drives, an apple falls, a cart rolls, etc. In all of these phenomena, objects (bodies) move. Phenomena associated with a change in the position of a body in relation to other bodies are called mechanical(translated from the Greek "mehane" means machine, tool).

Many phenomena are caused by the change of heat and cold. In this case, the properties of the bodies themselves change. They change shape, size, the state of these bodies changes. For example, when heated, ice turns into water, water into steam; When the temperature drops, steam turns into water, water into ice. The phenomena associated with the heating and cooling of bodies are called thermal(Fig. 35).

Rice. 35. Physical phenomenon: the transition of matter from one state to another. If you freeze drops of water, ice will reappear

Consider electrical phenomena. The word "electricity" comes from the Greek word "electron" - amber. Remember that when you quickly take off your woolen sweater, you hear a slight crackle. If you do the same in complete darkness, you will also see sparks. This is the simplest electrical phenomenon.

To get acquainted with another electrical phenomenon, do the following experiment.

Tear off small pieces of paper and place them on the table surface. Comb clean and dry hair with a plastic comb and bring it to the pieces of paper. What happened?

Rice. 36. Small pieces of paper are attracted to the comb

Bodies that are capable of attracting light objects after rubbing are called electrified(Fig. 36). Lightning during thunderstorms, auroras, electrification of paper and synthetic fabrics - all these are electrical phenomena. The operation of the telephone, radio, television, various household appliances are examples of human use of electrical phenomena.

Phenomena that are associated with light are called light. Light comes from the sun, stars, lamps, and some living things, such as fireflies. Such bodies are called luminous.

We see when light hits the retina. We cannot see in absolute darkness. Objects that do not themselves emit light (for example, trees, grass, the pages of this book, etc.) are visible only when they receive light from some luminous body and reflect it from their surface.

The moon, which we often speak of as a night light, is in reality only a kind of reflector of sunlight.

By studying the physical phenomena of nature, a person has learned to use them in everyday life, everyday life.

1. What are called natural phenomena?

2. Read the text. List what natural phenomena are called in it: “Spring has come. The sun is getting hotter. Snow melts, streams run. Buds swelled on the trees, rooks flew in.

3. What phenomena are called physical?

4. From the physical phenomena listed below, write down the mechanical phenomena in the first column; in the second - thermal; in the third - electrical; in the fourth - light phenomena.

Physical phenomena: lightning flash; snow melting; coast; melting of metals; operation of an electric bell; rainbow in the sky; sunbeam; moving stones, sand with water; boiling water.

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