Lightning always awakened a person’s imagination and desire to know the world. She brought fire to the earth, taming which, people became more powerful. We do not yet count on the conquest of this formidable natural phenomenon, but would like "peaceful coexistence." After all, the more perfect the equipment we create, the more dangerous atmospheric electricity is for it. One of the methods of protection is to preliminarily, using a special simulator, assess the vulnerability of industrial facilities for the current and electromagnetic field of lightning.

Loving the storm in early May is easy for poets and artists. The power engineer, signalman or astronaut will not be delighted from the beginning of the thunderstorm season: he promises too much trouble. On average, each square kilometer of Russia annually accounts for about three lightning strikes. Their electric current reaches 30,000 A, and for the most powerful discharges it can exceed 200,000 A. The temperature in a well-ionized plasma channel of even moderate lightning can reach 30,000 ° C, which is several times higher than in the electric arc of the welding machine. And of course, this does not bode well for many technical facilities. Fires and explosions from direct lightning are well known to specialists. But the townsfolk clearly exaggerate the risk of such an event ...

Recently, in the chandelier of one of the institutions of Bucharest, Edison's bulb was found miraculously discovered. To the surprise of those present, when it was turned on, it caught fire, but not instantly, as we used to, but flared up to a full glow for more than a minute. But this was not a defect of the bulb, although its service life was about 80 years ...

The path to creating a modern incandescent lamp, which seems elementary in design, was not very simple. To increase the light output, its thread needed to be heated to very high temperatures, but then it, even isolated from the air, quickly evaporated, and the light bulb “burned out”.

Inventors were looking for material that could withstand high temperatures. Metals were proposed: osmium, tantalum and tungsten, as well as carbon ...

German theorists from the University of Augsburg have proposed an original model of an electric motor operating on the laws of quantum mechanics. A specially selected external alternating magnetic field is applied to two atoms placed in a ring-shaped optical lattice at a very low temperature. One of the atoms, which scientists called the “carrier”, begins to move along the optical lattice and after a while reaches constant speed, the second atom plays the role of a “starter” - thanks to the interaction with it, the “carrier” begins its movement. The whole structure is called a quantum atomic engine.

The first working electric motor was designed and demonstrated in 1827 by the Hungarian physicist Agnos Jedlic. The improvement of various technological processes leads to the miniaturization of various devices, including devices for converting electrical or magnetic energy into mechanical energy. Almost 200 years after the creation of the first electric motor, their sizes reached the micrometer threshold and stepped into the nanometer region.

One of the many micro / nanoscale electric motor projects was proposed and implemented by American scientists in 2003 in an article ...

In modern electric power industry, radio engineering, telecommunication, automation systems, transformer is widely used, which is rightfully considered one of the common types of electrical equipment. The invention of the transformer is one of the great pages in the history of electrical engineering.Almost 120 years have passed since the creation of the first industrial single-phase transformer, the invention of which was worked from the 30s to the mid 80s of the XIX century, scientists, engineers from different countries.

Nowadays, thousands of various designs of transformers are known - from miniature to giant, for the transportation of which special railway platforms or powerful floating equipment are required.

As you know, when transmitting electricity over a long distance, a voltage of hundreds of thousands of volts is applied. But consumers, as a rule, cannot use such huge voltage directly. Therefore, the electricity generated at thermal power plants, hydroelectric power stations or nuclear power plants undergoes transformation, as a result of which the total power of transformers is several times higher than the installed capacity of generators in power plants. Energy losses in transformers should be minimal, and this problem has always been one of the main ones in their design.

The creation of a transformer became possible after the discovery of the phenomenon of electromagnetic induction by outstanding scientists of the first half of the XIX century. Englishman M. Faraday and American D. Henry. The experience of Faraday with an iron ring on which two windings isolated from each other were wound, the primary connected to the battery, and the secondary with a galvanometer, the arrow of which deviated when the primary circuit was opened and closed, is widely known. We can assume that the Faraday device was a prototype of a modern transformer. But neither Faraday nor Henry were the inventors of the transformer. They did not study the problem of voltage conversion, in their experiments the devices were fed with direct rather than alternating current and acted not continuously, but instantly at the moment the current was turned on or off in the primary winding ...

Hitachi has developed a new technology for generating electricity, using naturally occurring vibrations in the air with an amplitude of several micrometers.

HITACHI has developed a new technology for producing electric current through the use of natural processes of vibrations that occur in the air, which pass with an amplitude of a couple of micrometers. Despite the fact that this technology provides a very low electrical voltage, interest in it is very high due to the fact that such generators can work in any weather and natural conditions, which they cannot boast of, for example, solar panels ...

Even the last loafer, having studied for some time in the 10th grade, will tell the teacher that Ohm’s law is “U is equal to I times R”. Unfortunately, the smartest excellent student will say little more - the physical side of Ohm's law will remain a mystery to him for seven seals. I allow myself to share with my colleagues my experience in presenting this seemingly primitive topic.

The object of my pedagogical activity was the art and humanitarian 10th grade, whose main interests, as the reader guesses, lay very far from physics. That is why the teaching of this subject was entrusted to the author of these lines, who, generally speaking, teaches biology. It was a few years ago.

The lesson about Ohm's law begins with the trivial statement that electric current is the movement of charged particles in an electric field. If only an electric force acts on a charged particle, then the particle will accelerate in accordance with Newton’s second law. And if the vector of electric force acting on the charged particle is constant on the entire trajectory, then it is equally accelerated. Just like a weight falls under the influence of gravity.

But here the paratrooper drops completely wrong. If we neglect the wind, then its fall rate is constant.Even the student of the art and humanitarian class will answer that in addition to the force of gravity, another falling force acts on the falling parachute - the force of air resistance. This force is equal in absolute value to the force of attraction of the parachute by the Earth and is opposite to it in direction. Why?...

In most multi-storey buildings, stairwells usually have an electrical panel, where there are meters and circuit breakers for all apartments on the site. However, in detached houses and in the old fund, electricity panels often have to be installed on their own. And given the increased power consumption in our time, the installation of an electrical panel becomes a necessity.

You can purchase an electric switchboard with a single-phase electric meter and circuit breakers, either completed already assembled or assembled in parts. Personally, I recommend the first option to you, because finding such parts so that they all fit in the shield and can be securely fixed there is not easy.

Most importantly, before purchasing an electricity meter, you should consult your local energy sales department about this. That is, in a campaign that takes money from you for consumed electricity. The fact is that electric meters can be very different, both according to the principle of action, and according to their technical characteristics. This is mainly power and accuracy class. You need to find out these data in the energy supply from the controllers, write them down, and it is also advisable to find out the address of the store where these meters are sold. Usually, energy sales workers are willing to share this data, since then they themselves will be less trouble.

After you have decided on the choice of the meter, you need to first find out in the electrics store whether there is a ready-made panel with such an electric meter and circuit breakers (“automatic machines”). If there is, then you are lucky. And if not, then you have to buy everything separately. In this case, you will need: an electric meter, a shield (a box in which the meter and “automatic machines” will fit), circuit breakers (the number is determined by the number of power lines), a bar for installing “automatic machines” (din rail), a copper contact plate for connecting 8- 10 wires and 1 meter of copper three-core cable with a cross section of at least 2.5 mm for wiring ...

How to connect an analog voltmeter to a computer and highlight it.

Nowadays, high technology can often be found voltmeters / ammeters made in the form of an LCD indicator. But all this does not look as effective as an analog retro - a voltmeter flaunting on the front panel of your case! This article provides an overview and technical performance of mods in retro style.

The voltmeter is made in a traditional style and can work well with some cases. At radio bases, one can often see not only voltmeters, but also ammeters, which can also take place on the 5’25 plug. This voltmeter is capable of measuring DC voltage from 0 to 15 volts. This is what we need, because we will use a voltmeter as a 12 volt monitoring. Let's take a closer look. The lower part of the voltmeter is covered with a plastic cap. This technical maneuver is only for us - we can place a backlight under this cap ...

The more complex the chain, the more connections. If at least one contact is broken ...

When drawing up and installing an electrical circuit, it may be necessary to connect its parts and elements using terminals, clamps, plugs and sockets, thrust and threaded contacts and other special devices, and sometimes just twisting the bare ends of the connecting wires. Even in the simple electric circuit of a flashlight, you will count about a dozen such connections.

And the electrical circuits of household electrical appliances, tape recorders, televisions contain hundreds and even thousands of interconnected parts.

And each of these compounds should not only be mechanically strong, but also provide reliable electrical contact.

It is not so simple at all. If the conductors at the junction are not tightly pressed against each other or if their surface is covered with a film of oxides that conducts poorly electric current, then with an apparent strength of the connection it will be unreliable. And you already know that it is only in one place in the circuit to break the contact, how the current will stop and the device you made will stop working.

How to ensure the strength and reliability of numerous connections of elements and parts in complex electrical circuits? One of the most widely used methods for such a connection is soldering ...

A serious scientific experiment is chaotic, like war. The researcher often does not understand what is happening. The data obtained, as well as information from front-line intelligence, are usually contradictory. Further experiments have to be carried out “by touch” to obtain new facts. But in the end, the picture becomes clearer and then the “backdating” experimenter in the report describes a clear and precise sequence of his steps towards the goal, without mentioning the wrong ones. The main results of the experiments quite often lie not where the scientist was striving. However, the progress report looks like a triumphal procession from one truth to another, whether he wants it or not. Unfortunately, historians of science later work with such materials, which of course affects the quality of their work.

I would like to recall the story of one discovery that happened almost three centuries ago, which is now considered quite natural and taken for granted. Its authors are almost forgotten, but its significance for physics is no less than the voyage of Columbus to geography ...

“The thunder will not strike - the man will not cross himself”, “Do not put off until tomorrow what you can do today”, “Forge the iron while it's hot” - these are famous folk wisdom.

For centuries, people have felt in “their own skin” the justice of these expressions, regardless of what they did — eat up a mammoth in a cave or “chopped cabbage” at a “flea market”, sowed rye in the steppes of Ukraine or gathered votes in elections ...

In addition to applying these proverbs to certain events, the meaning implied in them can be transferred to entire periods in a person’s life.

He postponed his studies, "put" to work - and the years go by, and the person’s self-realization does not occur. As a result, negative consequences are not ruled out - “looked into the glass”, “stepped on a cork” or simply missed the time, which is not enough, how not to hope, then when the “cancer whistles” or “the cock bites” ...

I don't really like formulas. Like any normal person :) They cause me a headache and a desire to throw something into the wall. All my life I tried to stay away from them. And it turned out. But now I became interested in LEDs and realized - there’s no getting anywhere. To get the desired result, you need to understand how it works. Slowly, along the steps, I began to wade through the jungle of lumen, candela, and steradian. Gradually, a picture began to form in my head. And at the same time regret - well, why was there no one to explain it in a simple accessible language? So much time wasted ... I'll try to save you from a headache and explain as much as possible what an LED is and how it works. Well, at the same time, I will explain a couple of laws of optics :)

The article is dedicated to those who get confused in watts-candela-lumens-suites. And indeed in LEDs. Written by an advanced teapot for beginners dummies ...