Physical laws and limits of their application. Why are the laws of physics needed in everyday life?

Description

In order for a relationship to be called a physical law, it must satisfy the following requirements:

empirical confirmation. A physical law is considered true if it is confirmed by repeated experiments.
Versatility. The law must be fair for a large number of objects. Ideally - for all objects in the Universe.
Sustainability. Physical laws do not change with time, although they can be recognized as approximations to more precise laws.

Physical laws are usually expressed as a short verbal statement or a compact mathematical formula:

Examples

Main article: List of physical laws

Some of the most famous physical laws are:

Laws-principles

Some physical laws are universal in nature and are definitions in their essence. Such laws are often called principles. These include, for example, Newton's second law (definition of force), the law of conservation of energy (definition of energy), the principle of least action (definition of action), etc.

Laws-consequences of symmetries

Part of the physical laws are simple consequences of certain symmetries that exist in the system. So, the conservation laws according to Noether's theorem are consequences of the symmetry of space and time. And the Pauli principle, for example, is a consequence of the identity of electrons (the antisymmetry of their wave function with respect to the permutation of particles).

Approximation of laws

All physical laws are a consequence of empirical observations and are true with the same accuracy with which experimental observations are true. This restriction does not allow us to claim that any of the laws is absolute. It is known that some of the laws are obviously not absolutely accurate, but are approximations to more accurate ones. So, Newton's laws are valid only for sufficiently massive bodies moving at speeds much less than the speed of light. More precise are the laws of quantum mechanics and special relativity. However, they, in turn, are approximations of more accurate equations of quantum field theory.

Notes

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See what "Law (physics)" is in other dictionaries:

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Not a single sphere of human activity can do without the exact sciences. And no matter how complex human relationships are, they also come down to these laws. offers to remember the laws of physics that a person encounters and experiences every day of his life.

The simplest but most important law is The law of conservation and transformation of energy.

The energy of any closed system remains constant for all processes occurring in the system. And we are in such a closed system and we are. Those. how much we give, so much we get. If we want to get something, we must give the same amount before that. And nothing else!

And we, of course, want to get a big salary, but not go to work. Sometimes an illusion is created that “fools are lucky” and happiness falls on their heads for many. Read any fairy tale. Heroes constantly have to overcome huge difficulties! Then swim in the cold water, then in boiling water.

Men attract the attention of women with courtship. The women, in turn, take care of these men and the children. And so on. So, if you want to get something, take the trouble to give first.

The force of action is equal to the force of reaction.

This law of physics reflects the previous one, in principle. If a person has committed a negative act - conscious or not - and then received a response, i.e. opposition. Sometimes cause and effect are separated in time, and you can not immediately understand where the wind is blowing from. We must, most importantly, remember that nothing just happens.

The Law of the Lever.

Archimedes exclaimed: Give me a foothold and I will move the Earth!". Any weight can be carried if you choose the right lever. You should always estimate how long a lever will be needed to achieve a particular goal and draw a conclusion for yourself, set priorities: do you need to spend so much effort to create the right lever and move this weight, or is it easier to leave it alone and do other activities.

The gimlet rule.

The rule is that indicates the direction of the magnetic field. This rule answers the eternal question: who is to blame? And he points out that we ourselves are to blame for everything that happens to us. No matter how insulting it is, no matter how difficult it is, no matter how unfair it may seem at first glance, we must always be aware that we ourselves were the cause from the very beginning.

law of the nail.

When a person wants to hammer in a nail, he does not knock somewhere near the nail, he knocks exactly on the head of the nail. But the nails themselves do not climb into the walls. You must always choose the right hammer so as not to break the nail with a sledgehammer. And when scoring, you need to calculate the blow so that the hat does not bend. Keep it simple, take care of each other. Learn to think about your neighbor.

And finally, the law of entropy.

Entropy is a measure of the disorder of a system. In other words, the more chaos in the system, the greater the entropy. A more precise formulation: in spontaneous processes occurring in systems, entropy always increases. As a rule, all spontaneous processes are irreversible. They lead to real changes in the system, and it is impossible to return it to its original state without expending energy. At the same time, it is impossible to repeat exactly (100%) its initial state.

To better understand what kind of order and disorder we are talking about, let's set up an experiment. Pour black and white pellets into a glass jar. Let's put in the blacks first, then the whites. The pellets will be arranged in two layers: black on the bottom, white on top - everything is in order. Then shake the jar several times. The pellets will mix evenly. And no matter how much we then shake this jar, we are unlikely to be able to achieve that the pellets are again arranged in two layers. Here it is, entropy in action!

The state when the pellets were arranged in two layers is considered ordered. The state when the pellets are evenly mixed is considered disordered. It takes almost a miracle to return to an ordered state! Or repeated painstaking work with pellets. And it takes almost no effort to wreak havoc in a bank.

Car wheel. When it is pumped up, it has an excess of free energy. The wheel can move, which means it works. This is the order. What if you puncture a wheel? The pressure in it will drop, the free energy will "leave" in environment(dissipates), and such a wheel will no longer be able to work. This is chaos. To return the system to its original state, i.e. to put things in order, you need to do a lot of work: glue the camera, mount the wheel, pump it up, etc., after which this is again a necessary thing that can be useful.

Heat is transferred from a hot body to a cold one, and not vice versa. The reverse process is theoretically possible, but practically no one will undertake to do this, since enormous efforts, special installations and equipment will be required.

Also in society. People are getting old. Houses are crumbling. Rocks sink into the sea. The galaxies are scattered. Any reality surrounding us spontaneously tends to disorder.

However, people often talk about disorder as freedom: No, we do not want order! Give us such freedom that everyone can do what they want!» But when everyone does what they want, this is not freedom - this is chaos. In our time, many praise disorder, promote anarchy - in a word, everything that destroys and divides. But freedom is not in chaos, freedom is precisely in order.

Organizing his life, a person creates a reserve of free energy, which he then uses to implement his plans: work, study, recreation, creativity, sports, etc. In other words, it opposes entropy. Otherwise, how could we have accumulated so many material values over the past 250 years?!

Entropy is a measure of disorder, a measure of the irreversible dissipation of energy. The more entropy, the more disorder. A house where no one lives is falling into disrepair. Iron rusts over time, the car gets old. Relationships that no one cares about will break down. So is everything else in our life, absolutely everything!

The natural state of nature is not equilibrium, but an increase in entropy. This law works inexorably in the life of one person. He does not need to do anything to increase his entropy, this happens spontaneously, according to the law of nature. In order to reduce entropy (disorder), you need to make a lot of effort. This is a kind of slap in the face to stupidly positive people (under a lying stone and water does not flow), of which there are quite a lot!

Maintaining success requires constant effort. If we do not develop, then we degrade. And to keep what we had before, we must do more today than we did yesterday. Things can be kept in order and even improved: if the paint on a house has faded, it can be repainted, and even more beautiful than before.

People should try to “pacify” arbitrary destructive behavior that prevails everywhere in the modern world, try to reduce the state of chaos, which we have dispersed to grandiose limits. And this is a physical law, and not just a chatter about depression and negative thinking. Everything either develops or degrades.

A living organism is born, develops and dies, and no one has ever observed that after death it revives, becomes younger and returns to the seed or womb. When they say that the past never returns, then, of course, they mean, first of all, these vital phenomena. The development of organisms sets the positive direction of the arrow of time, and the change from one state of the system to another always occurs in the same direction for all processes without exception.

Valerian Chupin

Source of information: Tchaikovsky.News

Comments (3)

The wealth of modern society is growing, and will grow to an ever greater extent, primarily through universal labor. Industrial capital was the first historical form of social production, when universal labor began to be intensively exploited. And first, the one that he got for free. Science, as Marx observed, cost nothing to capital. Indeed, not a single capitalist paid a reward to either Archimedes, or Cardano, or Galileo, or Huygens, or Newton for the practical use of their ideas. But it is precisely industrial capital that, on a mass scale, begins to exploit mechanical technology, and thus the general labor embodied in it. Marx K, Engels F. Soch., vol. 25, part 1, p. 116.

Cheat sheet with formulas in physics for the exam

and not only (may need 7, 8, 9, 10 and 11 classes).

For starters, a picture that can be printed in a compact form.

Mechanics

Pressure P=F/S
Density ρ=m/V
Pressure at the depth of the liquid P=ρ∙g∙h
Gravity Ft=mg
5. Archimedean force Fa=ρ w ∙g∙Vt
Equation of motion for uniformly accelerated motion

X=X0 + υ 0∙t+(a∙t 2)/2 S=( υ 2 -υ 0 2) /2а S=( υ +υ 0) ∙t /2

Velocity equation for uniformly accelerated motion υ =υ 0 +a∙t
Acceleration a=( υ -υ 0)/t
Circular speed υ =2πR/T
Centripetal acceleration a= υ 2/R
Relationship between period and frequency ν=1/T=ω/2π
Newton's II law F=ma
Hooke's law Fy=-kx
Law of universal gravitation F=G∙M∙m/R 2
The weight of a body moving with acceleration a P \u003d m (g + a)
The weight of a body moving with acceleration a ↓ P \u003d m (g-a)
Friction force Ffr=µN
Body momentum p=m υ
Force impulse Ft=∆p
Moment M=F∙ℓ
Potential energy of a body raised above the ground Ep=mgh
Potential energy of elastically deformed body Ep=kx 2 /2
Kinetic energy of the body Ek=m υ 2 /2
Work A=F∙S∙cosα
Power N=A/t=F∙ υ
Efficiency η=Ap/Az
Oscillation period of the mathematical pendulum T=2π√ℓ/g
Oscillation period of a spring pendulum T=2 π √m/k
The equation of harmonic oscillations Х=Хmax∙cos ωt
Relationship of the wavelength, its speed and period λ= υ T

Molecular physics and thermodynamics

Amount of substance ν=N/ Na
Molar mass M=m/ν
Wed. kin. energy of monatomic gas molecules Ek=3/2∙kT
Basic equation of MKT P=nkT=1/3nm 0 υ 2
Gay-Lussac law (isobaric process) V/T =const
Charles' law (isochoric process) P/T =const
Relative humidity φ=P/P 0 ∙100%
Int. ideal energy. monatomic gas U=3/2∙M/µ∙RT
Gas work A=P∙ΔV
Boyle's law - Mariotte (isothermal process) PV=const
The amount of heat during heating Q \u003d Cm (T 2 -T 1)
The amount of heat during melting Q=λm
The amount of heat during vaporization Q=Lm
The amount of heat during fuel combustion Q=qm
The equation of state for an ideal gas is PV=m/M∙RT
First law of thermodynamics ΔU=A+Q
Efficiency of heat engines η= (Q 1 - Q 2) / Q 1
Ideal efficiency. engines (Carnot cycle) η \u003d (T 1 - T 2) / T 1

Electrostatics and electrodynamics - formulas in physics

Coulomb's law F=k∙q 1 ∙q 2 /R 2
Electric field strength E=F/q
Email tension. field of a point charge E=k∙q/R 2
Surface charge density σ = q/S
Email tension. fields of the infinite plane E=2πkσ
Dielectric constant ε=E 0 /E
Potential energy of interaction. charges W= k∙q 1 q 2 /R
Potential φ=W/q
Point charge potential φ=k∙q/R
Voltage U=A/q
For a uniform electric field U=E∙d
Electric capacity C=q/U
Capacitance of a flat capacitor C=S∙ ε ∙ε 0/d
Energy of a charged capacitor W=qU/2=q²/2С=CU²/2
Current I=q/t
Conductor resistance R=ρ∙ℓ/S
Ohm's law for the circuit section I=U/R
The laws of the last compounds I 1 \u003d I 2 \u003d I, U 1 + U 2 \u003d U, R 1 + R 2 \u003d R
Parallel laws. conn. U 1 \u003d U 2 \u003d U, I 1 + I 2 \u003d I, 1 / R 1 + 1 / R 2 \u003d 1 / R
Electric current power P=I∙U
Joule-Lenz law Q=I 2 Rt
Ohm's law for a complete chain I=ε/(R+r)
Short circuit current (R=0) I=ε/r
Magnetic induction vector B=Fmax/ℓ∙I
Ampere Force Fa=IBℓsin α
Lorentz force Fл=Bqυsin α
Magnetic flux Ф=BSсos α Ф=LI
Law of electromagnetic induction Ei=ΔФ/Δt
EMF of induction in moving conductor Ei=Вℓ υ sinα
EMF of self-induction Esi=-L∙ΔI/Δt
The energy of the magnetic field of the coil Wm \u003d LI 2 / 2
Oscillation period count. contour T=2π ∙√LC
Inductive reactance X L =ωL=2πLν
Capacitance Xc=1/ωC
The current value of the current Id \u003d Imax / √2,
RMS voltage Ud=Umax/√2
Impedance Z=√(Xc-X L) 2 +R 2

Optics

The law of refraction of light n 21 \u003d n 2 / n 1 \u003d υ 1 / υ 2
Refractive index n 21 =sin α/sin γ
Thin lens formula 1/F=1/d + 1/f
Optical power of the lens D=1/F
max interference: Δd=kλ,
min interference: Δd=(2k+1)λ/2
Differential grating d∙sin φ=k λ

The quantum physics

Einstein's formula for the photoelectric effect hν=Aout+Ek, Ek=U ze
Red border of the photoelectric effect ν to = Aout/h
Photon momentum P=mc=h/ λ=E/s

Physics of the atomic nucleus

Scientists from planet Earth use a ton of tools in an attempt to describe how nature works and in general. That they come to laws and theories. What is the difference? A scientific law can often be reduced to a mathematical statement, like E = mc²; this statement is based on empirical data and its truth, as a rule, is limited to a certain set of conditions. In the case of E = mc² - the speed of light in vacuum.

A scientific theory often seeks to synthesize a set of facts or observations of specific phenomena. And in general (but not always) there is a clear and verifiable statement about how nature functions. It is not at all necessary to reduce scientific theory to an equation, but it does represent something fundamental about the workings of nature.

Both laws and theories depend on the basic elements scientific method such as generating hypotheses, conducting experiments, finding (or not finding) empirical data, and drawing conclusions. After all, scientists must be able to replicate results if the experiment is to become the basis for a generally accepted law or theory.

In this article, we'll look at ten scientific laws and theories that you can brush up on even if you don't use a scanning electron microscope that often, for example. Let's start with an explosion and end with uncertainty.

If it is worth knowing at least one scientific theory, then let it explain how the universe reached its current state (or did not reach it). Based on studies by Edwin Hubble, Georges Lemaitre, and Albert Einstein, the Big Bang theory postulates that the universe began 14 billion years ago with a massive expansion. At some point, the universe was enclosed in one point and encompassed all the matter of the current universe. This movement continues to this day, and the universe itself is constantly expanding.

The Big Bang theory gained widespread support in scientific circles after Arno Penzias and Robert Wilson discovered the cosmic microwave background in 1965. Using radio telescopes, two astronomers have detected cosmic noise, or static, that does not dissipate over time. In collaboration with Princeton researcher Robert Dicke, the pair of scientists confirmed Dicke's hypothesis that the original Big Bang left behind low-level radiation that can be found throughout the universe.

Hubble's Cosmic Expansion Law

Let's hold Edwin Hubble for a second. While the Great Depression was raging in the 1920s, Hubble was performing groundbreaking astronomical research. Not only did he prove that there were other galaxies besides the Milky Way, but he also found that these galaxies were rushing away from our own, a movement he called receding.

In order to quantify the speed of this galactic motion, Hubble proposed the law of cosmic expansion, aka Hubble's law. The equation looks like this: speed = H0 x distance. Velocity is the speed of the recession of galaxies; H0 is the Hubble constant, or a parameter that indicates the expansion rate of the universe; distance is the distance of one galaxy to the one with which the comparison is made.

The Hubble constant has been calculated at different values for quite some time, but it is currently stuck at 70 km/s per megaparsec. For us it is not so important. The important thing is that the law is a convenient way to measure the speed of a galaxy relative to our own. And more importantly, the law established that the Universe consists of many galaxies, the movement of which can be traced to the Big Bang.

Kepler's laws of planetary motion

For centuries, scientists have battled each other and religious leaders over the orbits of the planets, especially whether they revolve around the sun. In the 16th century, Copernicus put forward his controversial concept of the heliocentric solar system where the planets revolve around the sun instead of the earth. However, it was not until Johannes Kepler, who drew on the work of Tycho Brahe and other astronomers, that a clear scientific basis for planetary motion emerged.

Kepler's three laws of planetary motion, developed in the early 17th century, describe the movement of planets around the sun. The first law, sometimes called the law of orbits, states that the planets revolve around the Sun in an elliptical orbit. The second law, the law of areas, says that the line connecting the planet to the sun forms equal areas at regular intervals. In other words, if you measure the area created by a drawn line from the Earth from the Sun and track the movement of the Earth for 30 days, the area will be the same regardless of the position of the Earth relative to the origin.

The third law, the law of periods, allows you to establish a clear relationship between the orbital period of the planet and the distance to the Sun. Thanks to this law, we know that a planet that is relatively close to the Sun, like Venus, has a much shorter orbital period than distant planets like Neptune.

Universal law of gravity

This may be par for the course today, but more than 300 years ago, Sir Isaac Newton proposed a revolutionary idea: any two objects, regardless of their mass, exert a gravitational attraction on each other. This law is represented by an equation that many schoolchildren encounter in the senior grades of physics and mathematics.

F = G × [(m1m2)/r²]

F is the gravitational force between two objects, measured in newtons. M1 and M2 are the masses of the two objects, while r is the distance between them. G is the gravitational constant, currently calculated as 6.67384(80) 10 −11 or N m² kg −2 .

The advantage of the universal law of gravity is that it allows you to calculate the gravitational attraction between any two objects. This ability is extremely useful when scientists, for example, launch a satellite into orbit or determine the course of the moon.

Newton's laws

While we're on the subject of one of the greatest scientists ever to live on Earth, let's talk about Newton's other famous laws. His three laws of motion form an essential part of modern physics. And like many other laws of physics, they are elegant in their simplicity.

The first of the three laws states that an object in motion remains in motion unless it is acted upon by an external force. For a ball rolling on the floor, the external force could be friction between the ball and the floor, or a boy hitting the ball in the other direction.

The second law establishes a relationship between the mass of an object (m) and its acceleration (a) in the form of the equation F = m x a. F is a force measured in newtons. It is also a vector, meaning it has a directional component. Due to the acceleration, the ball that rolls on the floor has a special vector in the direction of its movement, and this is taken into account when calculating the force.

The third law is quite meaningful and should be familiar to you: for every action there is an equal and opposite reaction. That is, for every force applied to an object on the surface, the object is repelled with the same force.

Laws of thermodynamics

The British physicist and writer C.P. Snow once said that an unscientist who did not know the second law of thermodynamics was like a scientist who had never read Shakespeare. Snow's now famous statement emphasized the importance of thermodynamics and the need even for people far from science to know it.

Thermodynamics is the science of how energy works in a system, whether it be an engine or the Earth's core. It can be reduced to a few basic laws, which Snow outlined as follows:

You cannot win.
You will not avoid losses.
You cannot exit the game.

Let's look into this a bit. What Snow meant by saying you can't win is that since matter and energy are conserved, you can't gain one without losing the other (that is, E=mc²). It also means that you need to supply heat to run the engine, but in the absence of a perfectly closed system, some heat will inevitably escape into the open world, leading to the second law.

The second law - losses are inevitable - means that due to increasing entropy, you cannot return to the previous energy state. Energy concentrated in one place will always tend to places of lower concentration.

Finally, the third law - you can't get out of the game - refers to the lowest theoretically possible temperature - minus 273.15 degrees Celsius. When the system reaches absolute zero, the movement of molecules stops, which means that entropy will reach its lowest value and there will not even be kinetic energy. But in the real world it is impossible to reach absolute zero - only very close to it.

Strength of Archimedes

After the ancient Greek Archimedes discovered his principle of buoyancy, he allegedly shouted "Eureka!" (Found!) and ran naked through Syracuse. So says the legend. The discovery was so important. Legend also says that Archimedes discovered the principle when he noticed that the water in the bathtub rises when a body is immersed in it.

According to Archimedes' principle of buoyancy, the force acting on a submerged or partially submerged object is equal to the mass of fluid that the object displaces. This principle is of paramount importance in density calculations, as well as in the design of submarines and other ocean-going vessels.

Evolution and natural selection

Now that we have established some of the basic concepts of how the universe began and how physical laws affect our daily lives, let's turn our attention to the human form and find out how we got to this point. According to most scientists, all life on Earth has a common ancestor. But in order to form such a huge difference between all living organisms, some of them had to turn into a separate species.

In a general sense, this differentiation has occurred in the process of evolution. Populations of organisms and their traits have gone through mechanisms such as mutations. Those with more survival traits, like brown frogs that camouflage themselves in swamps, were naturally selected for survival. This is where the term natural selection comes from.

You can multiply these two theories by many, many times, and actually Darwin did this in the 19th century. Evolution and natural selection explain the enormous diversity of life on Earth.

General theory of relativity

Albert Einstein's general theory of relativity was, and remains, a major discovery that forever changed our view of the universe. Einstein's main breakthrough was the statement that space and time are not absolute, and gravity is not just a force applied to an object or mass. Rather, gravity has to do with the fact that mass warps space and time itself (spacetime).

To make sense of this, imagine that you are driving across the Earth in a straight line in an easterly direction from, say, the northern hemisphere. After a while, if someone wants to accurately determine your location, you will be much south and east of your original position. This is because the earth is curved. To drive straight east, you need to take into account the shape of the Earth and drive at an angle slightly north. Compare a round ball and a sheet of paper.

Space is pretty much the same. For example, it will be obvious to the passengers of a rocket flying around the Earth that they are flying in a straight line in space. But in reality, the space-time around them is curving under the force of Earth's gravity, causing them to both move forward and stay in Earth's orbit.

Einstein's theory had a huge impact on the future of astrophysics and cosmology. She explained a small and unexpected anomaly in Mercury's orbit, showed how starlight bends, and laid theoretical basis for black holes.

Heisenberg uncertainty principle

Einstein's expansion of relativity taught us more about how the universe works and helped lay the groundwork for quantum physics, leading to a completely unexpected embarrassment of theoretical science. In 1927, the realization that all the laws of the universe are flexible in a certain context led to the startling discovery of the German scientist Werner Heisenberg.

Postulating his uncertainty principle, Heisenberg realized that it was impossible to know two properties of a particle simultaneously with a high level of accuracy. You can know the position of an electron with a high degree of accuracy, but not its momentum, and vice versa.

Later, Niels Bohr made a discovery that helped explain the Heisenberg principle. Bohr found that the electron has the qualities of both a particle and a wave. The concept became known as wave-particle duality and formed the basis of quantum physics. Therefore, when we measure the position of an electron, we define it as a particle at a certain point in space with an indefinite wavelength. When we measure the momentum, we consider the electron as a wave, which means we can know the amplitude of its length, but not the position.

It is natural and correct to be interested in the surrounding world and the laws of its functioning and development. That is why it is reasonable to pay attention to the natural sciences, for example, physics, which explains the very essence of the formation and development of the Universe. The basic physical laws are easy to understand. At a very young age, the school introduces children to these principles.

For many, this science begins with the textbook "Physics (Grade 7)". The basic concepts of and and thermodynamics are revealed to schoolchildren, they get acquainted with the core of the main physical laws. But should knowledge be limited to the school bench? What physical laws should every person know? This will be discussed later in the article.

science physics

Many of the nuances of the described science are familiar to everyone from early childhood. And this is due to the fact that, in essence, physics is one of the areas of natural science. It tells about the laws of nature, the action of which affects the life of everyone, and in many ways even provides it, about the features of matter, its structure and patterns of motion.

The term "physics" was first recorded by Aristotle in the fourth century BC. Initially, it was synonymous with the concept of "philosophy". After all, both sciences had a common goal - to correctly explain all the mechanisms of the functioning of the Universe. But already in the sixteenth century, as a result of the scientific revolution, physics became independent.

general law

Some basic laws of physics are applied in various branches of science. In addition to them, there are those that are considered to be common to all nature. This is about

It implies that the energy of each closed system, when any phenomena occur in it, is necessarily conserved. Nevertheless, it is able to transform into another form and effectively change its quantitative content in various parts of the named system. At the same time, in an open system, the energy decreases, provided that the energy of any bodies and fields that interact with it increases.

In addition to the above general principle, physics contains the basic concepts, formulas, laws that are necessary for interpreting the processes taking place in the surrounding world. Exploring them can be incredibly exciting. Therefore, in this article the basic laws of physics will be briefly considered, and in order to understand them deeper, it is important to pay full attention to them.

Mechanics

Many basic laws of physics are revealed to young scientists in grades 7-9 of the school, where such a branch of science as mechanics is more fully studied. Its basic principles are described below.

Galileo's law of relativity (also called the mechanical law of relativity, or the basis of classical mechanics). The essence of the principle lies in the fact that under similar conditions, mechanical processes in any inertial reference frames are completely identical.
Hooke's law. Its essence is that the greater the impact on an elastic body (spring, rod, cantilever, beam) from the side, the greater its deformation.

Newton's laws (represent the basis of classical mechanics):

The principle of inertia says that any body is capable of being at rest or moving uniformly and rectilinearly only if no other bodies influence it in any way, or if they somehow compensate for each other's action. To change the speed of movement, it is necessary to act on the body with some force, and, of course, the result of the action of the same force on bodies of different sizes will also differ.
The main pattern of dynamics states that the greater the resultant of the forces that are currently acting on a given body, the greater the acceleration received by it. And, accordingly, the greater the body weight, the lower this indicator.
Newton's third law states that any two bodies always interact with each other in an identical pattern: their forces are of the same nature, are equivalent in magnitude, and necessarily have the opposite direction along the straight line that connects these bodies.
The principle of relativity states that all phenomena occurring under the same conditions in inertial frames of reference proceed in an absolutely identical way.

Thermodynamics

The school textbook, which reveals to students the basic laws ("Physics. Grade 7"), introduces them to the basics of thermodynamics. We will briefly review its principles below.

The laws of thermodynamics, which are basic in this branch of science, are of a general nature and are not related to the details of the structure of a particular substance at the atomic level. By the way, these principles are important not only for physics, but also for chemistry, biology, aerospace engineering, etc.

For example, in the named industry there is a rule that cannot be logically determined that in a closed system, the external conditions for which are unchanged, an equilibrium state is established over time. And the processes that continue in it invariably compensate each other.

Another rule of thermodynamics confirms the desire of a system, which consists of a colossal number of particles characterized by chaotic motion, to an independent transition from less probable states for the system to more probable ones.

And the Gay-Lussac law (also called it states that for a gas of a certain mass under conditions of stable pressure, the result of dividing its volume by absolute temperature will certainly become a constant value.

Another important rule of this industry is the first law of thermodynamics, which is also called the principle of conservation and transformation of energy for a thermodynamic system. According to him, any amount of heat that was communicated to the system will be spent exclusively on the metamorphosis of its internal energy and the performance of work by it in relation to any acting external forces. It is this regularity that became the basis for the formation of a scheme for the operation of heat engines.

Another gas regularity is Charles' law. It states that the greater the pressure of a certain mass of an ideal gas, while maintaining a constant volume, the greater its temperature.

Electricity

Opens for young scientists interesting basic laws of physics 10th grade school. At this time, the main principles of nature and the laws of action of electric current, as well as other nuances, are studied.

Ampère's law, for example, states that conductors connected in parallel, through which current flows in the same direction, inevitably attract, and in the case of the opposite direction of current, respectively, repel. Sometimes the same name is used for a physical law that determines the force acting in an existing magnetic field on a small section of a conductor that is currently conducting current. It is called so - the power of Ampere. This discovery was made by a scientist in the first half of the nineteenth century (namely, in 1820).

The law of conservation of charge is one of the basic principles of nature. It states that the algebraic sum of all electric charges arising in any electrically isolated system is always conserved (becomes constant). Despite this, the named principle does not exclude the appearance of new charged particles in such systems as a result of certain processes. Nevertheless, the total electric charge of all newly formed particles must necessarily be equal to zero.

Coulomb's law is one of the fundamental in electrostatics. It expresses the principle of the force of interaction between fixed point charges and explains the quantitative calculation of the distance between them. Coulomb's law makes it possible to substantiate the basic principles of electrodynamics in an experimental way. It says that fixed point charges will certainly interact with each other with a force that is the higher, the greater the product of their magnitudes and, accordingly, the less, the less square the distances between the charges under consideration and the medium in which the described interaction occurs.

Ohm's law is one of the basic principles of electricity. It says that the greater the strength of the direct electric current acting on a certain section of the circuit, the greater the voltage at its ends.

They call the principle that allows you to determine the direction in the conductor of a current moving under the influence of a magnetic field in a certain way. To do this, it is necessary to position the right hand so that the lines of magnetic induction figuratively touch the open palm, and extend the thumb in the direction of the conductor. In this case, the remaining four straightened fingers will determine the direction of movement of the induction current.

Also, this principle helps to find out the exact location of the lines of magnetic induction of a straight conductor that conducts current at the moment. It works like this: place the thumb of the right hand in such a way that it points and figuratively grasp the conductor with the other four fingers. The location of these fingers will demonstrate the exact direction of the lines of magnetic induction.

The principle of electromagnetic induction is a pattern that explains the process of operation of transformers, generators, electric motors. This law is as follows: in a closed circuit, the generated induction is the greater, the greater the rate of change of the magnetic flux.

Optics

The branch "Optics" also reflects a part of the school curriculum (basic laws of physics: grades 7-9). Therefore, these principles are not as difficult to understand as it might seem at first glance. Their study brings with it not just additional knowledge, but a better understanding of the surrounding reality. The main laws of physics that can be attributed to the field of study of optics are as follows:

Huynes principle. It is a method that allows you to efficiently determine at any given fraction of a second the exact position of the wave front. Its essence is as follows: all points that are in the path of the wave front in a certain fraction of a second, in fact, become sources of spherical waves (secondary) in themselves, while the placement of the wave front in the same fraction of a second is identical to the surface , which goes around all spherical waves (secondary). This principle is used to explain the existing laws related to the refraction of light and its reflection.
The Huygens-Fresnel principle reflects an effective method for resolving issues related to wave propagation. It helps to explain the elementary problems associated with the diffraction of light.
waves. It is equally used for reflection in the mirror. Its essence lies in the fact that both the falling beam and the one that was reflected, as well as the perpendicular constructed from the point of incidence of the beam, are located in a single plane. It is also important to remember that in this case the angle at which the beam falls is always absolutely equal to the angle of refraction.
The principle of refraction of light. This is a change in the trajectory of an electromagnetic wave (light) at the moment of movement from one homogeneous medium to another, which differs significantly from the first in a number of refractive indices. The speed of propagation of light in them is different.
The law of rectilinear propagation of light. At its core, it is a law related to the field of geometric optics, and is as follows: in any homogeneous medium (regardless of its nature), light propagates strictly rectilinearly, along the shortest distance. This law simply and clearly explains the formation of a shadow.

Atomic and nuclear physics

The basic laws of quantum physics, as well as the fundamentals of atomic and nuclear physics, are studied in high school and higher education institutions.

Thus, Bohr's postulates are a series of basic hypotheses that have become the basis of the theory. Its essence is that any atomic system can remain stable only in stationary states. Any emission or absorption of energy by an atom necessarily occurs using the principle, the essence of which is as follows: the radiation associated with transport becomes monochromatic.

These postulates refer to the standard school curriculum that studies the basic laws of physics (Grade 11). Their knowledge is mandatory for the graduate.

Basic laws of physics that a person should know

Some physical principles, although they belong to one of the branches of this science, are nevertheless of a general nature and should be known to everyone. We list the basic laws of physics that a person should know:

Archimedes' law (applies to the areas of hydro-, as well as aerostatics). It implies that any body that has been immersed in a gaseous substance or in a liquid is subject to a kind of buoyant force, which is necessarily directed vertically upwards. This force is always numerically equal to the weight of the liquid or gas displaced by the body.
Another formulation of this law is as follows: a body immersed in a gas or liquid will certainly lose as much weight as the mass of the liquid or gas in which it was immersed. This law became the basic postulate of the theory of floating bodies.
The law of universal gravitation (discovered by Newton). Its essence lies in the fact that absolutely all bodies are inevitably attracted to each other with a force that is the greater, the greater the product of the masses of these bodies and, accordingly, the less, the smaller the square of the distance between them.

These are the 3 basic laws of physics that everyone who wants to understand the mechanism of the functioning of the surrounding world and the features of the processes occurring in it should know. It is quite easy to understand how they work.

The value of such knowledge

The basic laws of physics must be in the baggage of knowledge of a person, regardless of his age and type of activity. They reflect the mechanism of existence of all today's reality, and, in essence, are the only constant in a continuously changing world.

The basic laws, concepts of physics open up new opportunities for studying the world around us. Their knowledge helps to understand the mechanism of the existence of the Universe and the movement of all cosmic bodies. It turns us not just onlookers of daily events and processes, but allows us to be aware of them. When a person clearly understands the basic laws of physics, that is, all the processes taking place around him, he gets the opportunity to control them in the most effective way, making discoveries and thereby making his life more comfortable.

Results

Some are forced to study in depth the basic laws of physics for the exam, others - by occupation, and some - out of scientific curiosity. Regardless of the goals of studying this science, the benefits of the knowledge gained can hardly be overestimated. There is nothing more satisfying than understanding the basic mechanisms and laws of the existence of the surrounding world.

Don't be indifferent - develop!