Interesting facts about physics

Fun facts about physics can even touch the rainbow! The number of colors in it was determined by Isaac Newton. Aristotle was interested in such a phenomenon as a rainbow, and the Persian scientists discovered its essence back in the 13-14 century.

Why doesn't a bird sitting on a wire die from an electric shock?

A bird sitting on a wire of a high-voltage power line does not suffer from current, because its body is a poor conductor of current. In places where birds' paws touch the wire, a parallel connection is created, and since the wire conducts electricity much better, a very small current runs through the bird itself, which cannot cause harm. However, if the bird on the wire touches another grounded object, for example, the metal part of the support, it immediately dies, because then the air resistance compared to the body resistance is too high, and all the current flows through the bird.

What memory can metal alloys have?

Some metal alloys, such as nitinol (55% nickel and 45% titanium), have a shape memory effect. It consists in the fact that a deformed product made of such a material, when heated to a certain temperature, returns to its original shape. This is due to the fact that these alloys have a special internal structure called martensite, which has the property of thermoelasticity. In the deformed parts of the structure, internal stresses arise, which tend to return the structure to its original state. Shape memory materials are widely used in manufacturing - for example, for connecting sleeves, which shrink at very low temperatures and straighten at room temperatures, forming a connection much more reliable than welding.

How did the Pauli effect prevent Pauli from being played?

Scientists call the Pauli effect the failure of devices and the unplanned course of experiments when famous theoretical physicists appear - for example, the Nobel laureate Wolfgang Pauli. Once they decided to play him, connecting the wall clock in the hall where he was supposed to give a lecture, with the front door using a relay, so that when the door was opened, the clock would stop. However, this did not happen - when Pauli entered, the relay suddenly failed.

What color noise other than white noise is there?

The concept of "white noise" is widely known - this is how they say about a signal with a uniform spectral density at all frequencies and a dispersion equal to infinity. An example of white noise is the sound of a waterfall. However, in addition to white, a large number of other color noises are emitted. Pink noise is a signal in which the density is inversely proportional to the frequency, and the density of red noise is inversely proportional to the square of the frequency - they are perceived by ear as "warmer" than white. There are also concepts of blue, purple, gray noise and many others.

What elementary particles are named after the cry of the ducks?

Murray Gell-Mann, who hypothesized that hadrons are composed of even smaller particles, decided to call these particles the sound that ducks make. The novel by James Joyce "Finnegans Wake" by James Joyce, namely the line: "Three quarks for Muster Mark!", Helped him to form this sound into a suitable word. Hence, the particles got the name quarks, although it is not at all clear what meaning this previously nonexistent word had in Joyce.

Why is the sky blue during the day and red at sunset?

The short-wavelength components of the solar spectrum are scattered more strongly in the air than the long-wavelength components. This is why we see the sky as blue, because blue is at the shortwave end of the visible spectrum. For a similar reason, at sunset or dawn, the sky on the horizon turns red. At this time, the light travels tangentially to the earth's surface, and its path in the atmosphere is much longer, as a result of which a significant part of the blue and green color due to scattering leaves direct sunlight.

What is the difference between the water lapping mechanism of cats and dogs? [/ b]

In the process of lapping, cats do not immerse their tongue in water, but, slightly touching the surface with a curved tip, immediately pull it back up. In this case, a column of liquid is formed due to the finest balance of gravity, which pulls the water down, and the force of inertia, forcing the water to continue moving up. A similar lapping mechanism is used by dogs - although it may seem to the observer that the dog is scooping up liquid with its tongue folded into the shoulder blade, X-ray analysis showed that this "shoulder blade" unfolds inside the mouth, and the water column created by the dog is similar to that of a cat.

[b] Who has both Nobel and Nobel Prizes?

Dutch physicist of Russian origin Andrei Geim received the Nobel Prize in 2010 for experiments that helped study the properties of graphene. And 10 years earlier, he received the ironic Shnobel Prize for an experiment on diamagnetic levitation of frogs. Thus, Geim became the first person in the world to own both the Nobel and the Nobel Prizes.

Why are ordinary city streets dangerous for racing cars?

When a race car is driving on a track, there can be very little pressure between the bottom of the car and the road, enough to lift the manhole cover. This happened, for example, in Montreal in 1990 at the race of sports prototypes - a cover lifted by one of the cars hit the next car, which started a fire and the race was stopped. Therefore, now in all races of cars on city streets, covers are welded to the rim of the hatch.

Why did Newton throw a foreign object into his eye?

Isaac Newton was interested in many aspects of physics and other sciences, and was not afraid to carry out some experiments on himself. He tested his guess that we see the world around us due to the pressure of light on the retina of the eye as follows: he cut out a thin curved probe from ivory, launched it into his eye and pressed it on the back of the eyeball. The resulting colored flashes and circles confirmed his hypothesis.

Why is the unit of measurement for both temperature and strength of alcoholic drinks called the same - degree?

In the 17th and 18th centuries, there was a physical theory about caloric - weightless matter found in bodies and causing thermal phenomena. According to this theory, more heated bodies contain more caloric than less heated ones, therefore the temperature was defined as the strength of the mixture of the substance of the body and caloric. That is why the unit of measurement for both temperature and strength of alcoholic beverages is called the same - degree.

Why are the two German-American satellites named Tom and Jerry?

In 2002, Germany, together with the United States, launched a system of two space satellites to measure Earth's gravity called GRACE. They fly in one orbit at an altitude of about 450 kilometers one after another, with an interval of 220 kilometers. When the first satellite flies up to an area with increased gravity, such as a large mountain range, it accelerates and moves away from the second satellite. And after a while the second device also flies here, also accelerates and thereby restores the original distance. For such a game of "catch-up" satellites were named Tom and Jerry.

Why can't the American SR-71 Blackbird reconnaissance aircraft be fully refueled on the ground?

The American reconnaissance aircraft SR-71 Blackbird at normal temperatures has gaps in its skin. In flight, the skin heats up due to friction against the air, and the gaps disappear, and the fuel cools the skin. Due to this method, the plane cannot be refueled on the ground, because the fuel will leak out through the very slots. Therefore, at first, only a small amount of fuel is refueled into the plane, and refueling takes place in the air.

Where can water freeze at +20 ° C?

Water can freeze in the pipeline at a temperature of +20 ° C if methane is present in this water (more precisely, a gas hydrate is formed from water and methane). Methane molecules "push" water molecules as they occupy a larger volume. This leads to a decrease in the internal water pressure and an increase in the freezing point.

Whose Nobel medals were hidden from the Nazis in dissolved form?

In Nazi Germany, the Nobel Prize was banned after the 1935 Peace Prize was awarded to the enemy of National Socialism Karl von Ossietzky. German physicists Max von Laue and James Frank entrusted the storage of their gold medals to Niels Bohr. When the Germans occupied Copenhagen in 1940, the chemist de Hevesy dissolved these medals in aqua regia. After the end of the war, de Hevesy extracted the gold hidden in royal vodka and gave it to the Royal Swedish Academy of Sciences. New medals were produced there and re-presented to von Laue and Frank.

Which famous physicist was awarded the Nobel Prize in Chemistry?

Ernest Rutherford was mainly engaged in research in the field of physics and once said that "all sciences can be divided into two groups - physics and stamp collecting." However, the Nobel Prize was awarded to him in chemistry, which came as a surprise both to him and to other scientists. Subsequently, he noticed that of all the transformations that he was able to observe, "the most unexpected was his own transformation from a physicist to a chemist."

Why do insects hit the lamps?

Insects are guided in flight by the light. They fix the source - the Sun or the Moon - and maintain a constant angle between it and their course, taking such a position in which the rays always illuminate the same side. However, if the rays from the heavenly bodies are almost parallel, then from an artificial light source the rays diverge radially. And when an insect chooses a lamp for its course, it moves in a spiral, gradually approaching it.

How do you tell a boiled egg from a raw one?

If a boiled egg is rolled on a smooth surface, it will quickly roll in a given direction and will spin for a long time, while a raw egg will stop much earlier. This is because a tough egg rotates as a whole, while a raw egg has a liquid content that is weakly bound to the shell. Therefore, when rotation begins, the liquid content, due to the inertia of rest, lags behind the rotation of the shell and slows down the movement. It is also possible to stop the rotation for a short moment during rotation with your finger. For the same reasons, a boiled egg will stop immediately, and a raw egg will continue to spin after you remove your finger.

Why is the rainbow in the shape of an arc?

The sun's rays, passing through raindrops in the air, decompose into a spectrum, since different colors of the spectrum are refracted in the drops at different angles. As a result, a circle is formed - a rainbow, part of which we see from the ground in the form of an arc, and the center of the circle lies on the straight line "The sun is the eye of the observer". If the light in the droplet is reflected twice, then a secondary rainbow can be seen.

How does ice flow?

Ice is subject to fluidity - the ability to deform under stress causes ice to move in huge glaciers. Some Himalayan glaciers move at a speed of 2-3 meters per day.

Why can Asians and Africans wear weights on their heads?

The inhabitants of Africa and Asia easily carry heavy loads on their heads. This is due to the laws of physics. When walking, the body of a person rises and falls, thus energy is expended on lifting the load. At the same time, the head rises and falls with a smaller vertical amplitude than the entire body, and this feature was developed in an evolutionary way: the brain was protected from concussion, while a springy spine with a double bend served as a spring.

Why is it possible to increase the freezing speed of water by preheating it?

In 1963, a student from Tanzania, Erasto Mpemba, discovered that hot water freezes faster in a freezer than cold water. In honor of him, this phenomenon was called the Mpemba effect. Until now, scientists have not been able to accurately explain the cause of the phenomenon, and the experiment is not always successful: it requires certain conditions.

Why doesn't ice sink in water?

Water is the only naturally occurring substance on Earth, the density of which in a liquid state is greater than in a solid one. Therefore, ice does not sink in water. It is because of this that reservoirs usually do not freeze to the bottom, although at extreme air temperatures this is possible.

What influences the swirling direction of the water funnel?

The Coriolis force caused by the rotation of the Earth on its own axis does not in any way affect the twisting of the funnel of water in the bathroom. Its effect can be seen in the example of twisting air masses (clockwise in the southern hemisphere and counterclockwise in the northern), but this force is too small to spin a small and fast funnel. The direction of rotation of the water in it depends on other factors, such as the direction of the threads in the drain hole or the configuration of the pipes.

Who is considered the world's first programmer?

The world's first programmer was a female Englishwoman, Ada Lovelace. In the middle of the 19th century, she drew up a plan of operations for the prototype of a modern computer - Charles Babbage's analytical machine, with the help of which it was possible to solve the Bernoulli equation, which expresses the law of conservation of energy of a moving fluid.

What particles can rise from the core of the Sun to its surface for a million years?

Light travels more slowly in a transparent medium than in a vacuum. For example, photons undergoing multiple collisions on their way from the solar core emitting energy can take about a million years to reach the surface of the Sun. However, moving in open space, the same photons reach the Earth in just 8, 3 minutes.

When was the Earth's gravitational field weakened?

On April 1, 1976, the English astronomer Patrick Moore played a prank on the audience on BBC radio, announcing that at 9:47 a.m. a rare astronomical effect would occur: Pluto would pass behind Jupiter, enter into gravitational interaction with it and slightly weaken the Earth's gravitational field. If the listeners jump up at this moment, they must feel a strange feeling. Beginning at 9:47 am, the BBC received hundreds of calls with stories of the strange feeling, and one woman even stated that she and her friends had lifted themselves from chairs and were flying around the room.

Why are there 7 colors in a rainbow?

Although the multicolor spectrum of the rainbow is continuous, traditionally 7 colors are distinguished in it. It is believed that Isaac Newton was the first to choose this number. Moreover, initially he distinguished only five colors - red, yellow, green, blue and violet, which he wrote about in his Optics. But later, in an effort to create a correspondence between the number of colors in the spectrum and the number of fundamental tones of the musical scale, Newton added two more colors.

Why did Dirac want to refuse the Nobel Prize?

When the English physicist Paul Dirac was awarded the Nobel Prize in 1933, he wanted to refuse it because he hated advertising. However, Rutherford still persuaded a colleague to receive the award, since a refusal would have become even more publicity.

What did the inventor of the radar say when he exceeded the speed limit?

Scottish physicist Robert Watson-Watt was once stopped by a police officer for speeding, after which he said: "If I knew what you would do with him, I would never have invented radar!"

What makes snowflakes unique?

Due to the huge variety of snowflake shapes, it is believed that no two snowflakes with the same crystal structure exist. According to some physicists, there are more variants of such forms than atoms in the observable Universe.

How did maritime smugglers hide alcohol from US customs officials during Prohibition?

During Prohibition in the United States, most of the smuggled liquor came by sea. The smugglers prepared in advance for surprise customs searches at sea. They tied a bag of salt or sugar to each box, and when danger approached, they threw it into the water. After a certain time, the contents of the bags were dissolved by water, and the loads floated up.

What did the Celsius scale originally look like?

In the original Celsius scale, the freezing point of water was taken as 100 degrees, and the boiling point of water as 0. This scale was inverted by Karl Linnaeus, and is used in this form until our time.

Which Einstein's discovery was awarded the Nobel Prize?

In the archives of the Nobel Committee, about 60 Einstein nominations have been preserved in connection with the formulation of the theory of relativity, but the prize was awarded only for the explanation of the photoelectric effect.