Weightlessness - interesting facts. Ways to experience the feeling of weightlessness in theory and practice. Astronauts eat not only from tubes
DEPARTMENT OF EDUCATION OF MOSCOW
ZELENOGRAD DISTRICT DEPARTMENT OF EDUCATION TO MOSCOW
State budgetary educational institution
Secondary school №853
About weightlessness
The project was made by:
Altukhova Anna
Maksakova Maria
Mitrofanova Yana
Curated by: math teacher
Popkova Lyudmila Grigorievna
Shorty Znayka from Nikolai Nosov's fairy tale novel "Dunno on the Moon" invented a zero gravity device. With the help of the device, the gravity was not destroyed, but rather shifted from the center where the device was located by several tens of meters around. At the same time, an increased severity was felt near the border of the zero gravity zone.
Calculate how many advantages (and what) does this weightlessness give? What (and how much) inconvenience does it cause?
Objective of the project
- The goal of the project is to give the concept of weightlessness in an integrated form (i.e., to consider it from different angles), to note the relevance of this concept not only in the study of outer space, the negative impact on humans, but also in the framework of the possibility of using the technologies invented for reducing this impact; carrying out some technological processes that are difficult or impossible to implement in terrestrial conditions. Find out what are the advantages and what are the disadvantages of weightlessness
Project objectives
- Understand the mechanism of this phenomenon;
- Describe this mechanism mathematically and physically;
- Tell interesting facts about weightlessness;
- To understand how the state of weightlessness affects the health of people in a spaceship, station, etc., that is, to look at weightlessness from a biological and medical point of view;
The history of weightlessness
The disappearance of weight when the support moves with the acceleration of gravity only under the action of gravity is called weightlessness .
There are two types of weightlessness.
Weight loss that occurs at a great distance from celestial bodies due to the weakening of attraction is called static weightlessness. And the state in which a person is during orbital flight is dynamic weightlessness. They appear in exactly the same way. Human feelings are the same. But the reasons are different.
In flight, astronauts deal only with dynamic weightlessness.
Consider the case: An airplane is flying. In the cockpit, two parachutists prepared to jump. The earth pulls them down. And they still resist. They put their feet on the floor of the plane. Feel the attraction of the Earth - the soles of their feet are pressed against the floor. They feel their weight. "The strap is stretched."
But then they agreed to follow where the Earth pulls them. We stood on the edge of the hatch and jumped down. "The strap is loose." Immediately, the feeling of the Earth's gravitation disappeared. They became weightless.
It is interesting
In zero gravity, boiling becomes a much slower process.
In zero gravity, the candle flame takes on a spherical shape.
And everything inside our body is adapted to the conditions of weight. The heart has powerful muscles, designed to continuously pump several kilograms of blood. And if down, into the legs, it still flows easily, then up, into the head, it must be fed with force. All of our internal organs suspended on strong ties. If they were not there, the insides would "slide" down, huddled there in a heap. Due to the constant weight, we have developed a special organ, the vestibular apparatus, located in the depths of the head, behind the ear.
- Astronauts sooner or later develop space sickness, which is accompanied by headaches and joint problems when moving. But this is only part of the problem. When the astronaut is in zero gravity, all the fluid that is in the body rises upward and causes a blockage in the nasopharynx and swelling in the face. Muscles begin to atrophy as unnecessary, there is less and less calcium in the bones, and the intestines work 2 times slower.
- Another bonus from zero gravity is the increased height due to low pressure. It affects the spine and the person grows at least 5 cm.
- Those returning from space report that weightlessness makes it very difficult to move their arms and legs immediately after arrival. Therefore, landing is called a second birth by many.
- There are also problems with adaptation to the perception of attraction. If an object falls, it still falls, and this is somewhat unusual for astronauts.
Device advantages
this device can be used wisely, for good (during the war, it was possible to make a tower in which the device would be located; when an army of enemies approached, a button was pressed and the enemy moved to a safe distance)
You can make a stop-type station in which the device was installed and people would go to this station, press a button and move a set distance
Can be used as a small, or maybe not a small trick; at the Olympics, an athlete during the long jump
Flaws
in the task it is written: "Near the boundary of the zero gravity zone at the same time
there was an increased severity. "That is, there was a certain
pressure inside the body being moved, which can lead to
unfortunate consequences for the moved object (for the first
point of advantages is even a plus enemy
destroyed)
The device is not suitable for individual use; Again, a quote from the assignment: "With the help of the device, the gravity was not destroyed, but as if it was displaced FROM THE CENTER, where the DEVICE IS LOCATED ..." come back for her
conclusions
Weightlessness occurs when the body freely falls along with the support, i.e. the acceleration of the body and the support is equal to the acceleration of gravity;
2) Weightlessness is of two types: static and dynamic;
3) Weightlessness can be used for the implementation of some technological processes that are difficult or impossible to implement in terrestrial conditions;
4) The study of the flame in zero gravity is necessary when developing special means fire extinguishing;
- The effect of weightlessness on the body is
negative, as it causes a change in a number of its vital functions. This can be corrected by creating artificial gravity on the spacecraft, limiting the muscular activity of the astronauts.
6) Zero gravity conditions violate the ability to correctly assess the size of objects and the distance to them, which prevents astronauts from orienting themselves in the surrounding space and can lead to accidents during space flights
The device allows you to easily move objects (for example, during construction), but at the same time, it is necessary to provide for their fixation on the surface, and destruction of structures can occur at the border of the zone if they are not designed for the resulting increase in gravity. If these balls are placed near a tornado, then it will lose its strength. Conditions like inside an orbiting space station.
Wearing a semblance, wings on your hands or another engine, and placing the device behind your back, you can fly.
Experiments can be carried out under conditions similar to those on an orbiting space station (for example, growing crystals). Some animals may die.
Special tools are needed to work in zero gravity conditions. For the vital activity of organisms, it is necessary to mix the gaseous medium for breathing. At the border of the zone where the severity is increased, the body can die if the severity (overload) exceeds the limit of its endurance. Ponds can be inconvenient, since the water will take the shape of a ball and move with air currents.
In the distant future, a device for weightlessness was invented, now, with the help of such a device, things are transported from the earth into space (for astronauts into orbit).
The device itself looks like a toaster with two antennas. He creates a cylinder with a radius of 1.5 m from below, things are put into this cylinder and they are sent to the top. However, this device has 1, but a rather significant drawback: since this cylinder has no material boundaries, if the load has not yet reached space, it can go beyond its boundaries and fall at a much higher speed, since in this case the attraction to the earth increases by repeatedly.
Cause weightlessness lies in the fact that the force of universal gravitation imparts the same acceleration to the body and its support. Therefore, any body that moves only under the influence of the forces of universal gravity is in a state of weightlessness. It is in such conditions that a freely falling body is found.
Bibliography
1. Big Soviet Encyclopedia. Ch. ed. A.M. Prokhorov.
2.Kabardin O.F. Physics: Reference Materials: A Study Guide.
3. Kolesnikov Yu.V., Glazkov Yu.N. A spaceship is in orbit.
In more detail about what it is and where it can be felt, and will be discussed in this article.
Static
There are two types of weightlessness. It is static - observed when moving away from an object with a large mass. For example, a body that has flown a considerable distance from the planet. It should be understood, however, that its weight does not completely disappear.
The fact is that gravity from massive objects such as planets and stars, although it decreases with distance, does not completely disappear. Its action extends infinitely far to all corners of the Universe, inversely proportional to the square of the distance. This follows from the definition of weightlessness.
So get out of range gravitational field impossible.
Dynamic
Another type of weightlessness is dynamic. It is constantly tested by astronauts and pilots. Neutralize the action of the gravitational field massive object possible by free falling on it. This requires the object to gain a certain speed and become a satellite.
Having gained the required speed, the satellite begins to move into a state of constant free fall. The objects inside it will be in a state of weightlessness. This speed is called the first cosmic speed.
For planet Earth, for example, the speed is about 8 kilometers per second. For the Sun - already 640. It all depends on the mass of the object and its density. In such places where the density reaches hundreds of millions of tons per cubic centimeter, the cosmic speed approaches the speed of light.
Weightlessness on Earth
It turns out that one can experience the state of weightlessness without leaving the planet. True, for a very short period. For example, a passenger in a car driving on a curved bridge will experience weightlessness for a while at the top of the bridge bulge.
Passengers traveling in public transport on bumpy roads constantly experience the effect of weightlessness every time the bus runs into a hole or bump. For a short period of time, they are in a state of free fall.
Entertainment
Recently, special training grounds have appeared in the entertainment industry, where everyone can experience weightlessness.
After passing a medical commission and paying a certain amount of money, you can get on board an airplane that flies along a wave-like trajectory, and during a peak, people can experience an unusual feeling of weightlessness for half a minute.
The pilot of the aircraft through the intercom announces the beginning of the effect of weightlessness. This is necessary for security reasons. The fact is that after a free fall, the plane is rapidly gaining altitude. At the same time, people on board experience a diametrically opposite effect - overload.
Sometimes this value reaches three times the value of the acceleration due to gravity. In other words, the weight of the body in zero gravity will be three times its natural weight. Falling from a height of several meters with such a body weight can be very easily injured.
For these purposes, specially trained instructors sit on board the aircraft in the zero-gravity compartment. Their task is to put those people who did not manage to meet the given time interval to the floor of the plane in time.
A series of ups and downs occurs with a frequency of up to twenty times during one plane flight.
In Russia, for example, for those wishing to experience weightlessness there is a special centrifuge, which is located in the center for training cosmonauts and pilots. Again, after a medical examination and a monetary contribution of about 55 thousand rubles, a person can feel the effect of weightlessness.
Influence on the human body
By definition, weightlessness is absolutely harmless to the human body. Difficulties begin when it lasts for several days, weeks or months.
In most cases, this only applies to the inhabitants of space stations. Astronauts who have been on board for a long time begin to experience significant discomfort. This is primarily due to the vestibular mechanism.
On Earth, under usual conditions, the otoliths of the vestibular apparatus press on the nerve endings, thus prompting our brain where the top and bottom are, orienting the human body in space.
Weight and weightlessness
It's quite another matter when the body weighs nothing. All processes in it proceed differently. Due to the lack of pressure from the otoliths, a violation of orientation in space occurs. The concept of "up" and "down" in space completely disappears. Lack of physical activity also harms the human body. In this condition muscle atrophies if no action is taken. With its degradation, it suffers and bone... In the absence of load, less phosphorus enters the bones of the body.
Difficulty eating and swallowing fluids. At the same time, all liquids tend to take a spherical shape, which makes everyday things very difficult. Even a common runny nose in zero gravity can be a very difficult test for the body due to the fact that phlegm is not removed by gravity, but form spherical drops.
To maintain the required tone, astronauts constantly train for several hours a day. When going to bed, they tie themselves with special straps so as not to get injured during sleep.
To feed the astronauts, special food in tubes and bread that does not crumble have been developed.
Before experiencing weightlessness for a long time, a person must feel its effect on the ground in order to find out how the absence of gravity will affect him in the future.
The force of gravity is an integral part of our life, although we also perceive it as something commonplace. I. Newton, thanks to the falling apple on his head, developed this theory, but gravity is something more.
Before Newton, scientists such as Kepler, Descartes, Epicurus and others also philosophized about the existence of such a force. But, by and large, they believed that there are two attractions: heavenly (in space) and earthly (on the surface of the planet). Isaac Newton went a little further, he connected these two concepts. In addition, the legend that he was walking in the garden and an apple fell on him is actually a fiction and just a beautiful story.
Gravity is the force of attraction between objects in proportion to their mass. Obi-Wan Kenobi mentioned in the world famous film that “the power is around us and penetrates us. It holds the Galaxy together. " However, if good and evil act according to the dual principle, then the force of attraction only attracts objects to each other, but does not repel them. Gravity is around us. This is the force that keeps the planet in the shape of a sphere, it does not allow us to leave the surface. And gravity also keeps our atmosphere around it and prevents it from floating in space. Below are some of the most interesting facts about the force of gravity.
Many believe that astronauts on the space station and fans of extreme entertainment at speed experience "zero" gravity, ie. for some time they are not subject to gravity at all. In fact, this is a fundamentally wrong statement, since they tend downward at the same speed as the object in which they are.
The force of gravity acts equally on all objects, regardless of their weight. For example, if you drop two cinder blocks of the same parameters, but different in weight, from a height, they will touch the surface of the earth together. The additional speed of an object that is lighter in weight overlaps with the inertia of a heavier object.
It turns out that the greater the weight of the cosmic body, the heavier the objects on it. This means that one and the same person, who has a weight of fifty kilograms on our planet, would weigh 2 times more on Saturn.
The force of gravity on a planet is determined by its size. For example, on Mars, the force of gravity is much less than on our planet. This fact negatively affects the human body, so a person cannot be on this planet for a long time.
Jupiter is neither a planet nor a star. It has sufficient gravitational force to gain the necessary weight and become a full-fledged star, a heavenly body, but its field is too weak and cannot start the transformation of the planet.
Interesting fact! In the absence of gravity, i.e. in a state of weightlessness, all liquids take the form of a ball. You will not be able to wash your hands or pour water from vessel to vessel. Therefore, in order to feel comfortable in space, astronauts get used to it for a long time. Even sleep is unusual for them, because they sleep in bags that are attached to the walls of the ship. In addition, it is more difficult for astronauts to sleep, because the phases of sleep and wakefulness of a person depend on sunsets and dawns, and in space between these two processes there are only 90 minutes, i.e. 8 cycles are observed in a day.
Many people think that there is no gravity in space. In fact, this is a false statement. The force of gravity is almost everywhere, but it acts with different strengths. As you know, the force of gravity between two bodies is inversely proportional to the distance between them and proportional to the product of their weight. Due to the fact that the earth's radius is slightly less than the orbital altitude of the International Space Station (by about 10 percent), therefore, the force of gravity is less there and tends to zero.
A flame in the absence of gravity also behaves differently than we are used to. This is because on Earth, during combustion, air saturated with carbon dioxide rises, at that time, making room for oxygen. There is no such change of air under weightless conditions, therefore, over time, all the oxygen around the fire burns out, and the combustion process stops. Due to the absence of air convection in space, not only the flame suffers, but also the person, because during his immobility, oxygen also does not circulate around and ends. For such situations in the compartments spaceships fans for artificial air circulation are provided.
According to the theory of scientists, it is the force of gravity that plays a role in determining the height of mountains on Earth. Thus, for our planet, the maximum height of the mountains will be a distance of no more than 15 kilometers. For example, if the Sun became a neural star, then its powerful gravity would not allow such a phenomenon as mountains to appear, in principle.
It turns out that the force of gravity in the center of the Earth would act on objects (if it were possible to place them there) differently than on the surface of the planet. In the core of the planet, objects would be pulled simultaneously on all four sides, which, in principle, is similar to the situation in a state of weightlessness.
Gravity affects not only objects, but also influences many calculations and factors. It turns out that its potential has a significant impact on timing. Relatively recently, physicists from Denmark have proved that the center of our planet is younger than its surface. The lower the gravity, the slower the time. According to hypothetical measurements, the ages of the core and crust of celestial bodies differ significantly in favor of their center.
We all know, and have previously mentioned that the presence of force itself on Earth was discovered by the scientist Newton in the 17th century. But few people know that in fact he described only part of this power. For many years, scientists have tried to perfect this theory. Another famous genius stated that the force of gravity is just the curvature of time-space created by the mass of this object. This scientist was Einstein, and it was only in the 20th century that he became closer to solving this phenomenon. But in fact, gravity holds many more secrets that are beyond our control for this moment and the future remains to be unraveled.
Humanity takes gravity for granted. Everyone knows the theory of universal gravitation, which was developed by Isaac Newton. However, when it comes to gravity - the force that attracts objects and objects to each other - this is already something more. Here are some facts about the force of gravity.
1.
Earth's gravity is a fairly constant force. However, people's perception of this power suggests that this is not so. Studies have shown that it is easier for a person to judge how an object falls to the ground when it is in an upright position (for example, sitting), rather than horizontally (lying down). This means that the human perception of gravity is not based on visual signals about the direction of gravity and depends on the position of the body in space.
2. It is difficult to return to Earth.
As the experience of astronauts shows, the transition to zero gravity and back is a difficult and difficult process for the body. In the absence of gravity, muscles atrophy and bones lose bone mass. Therefore, in a month in space, astronauts can lose up to 1% of bone mass.
Upon the return of astronauts to Earth, their bodies and brains take a certain amount of time to recover. If in space blood pressure is evenly distributed throughout the body, then after returning to Earth, the heart must work in such a way as to supply the brain with blood. Sometimes the consequences of being in space make themselves felt: in 2006, astronaut Heidemarie Stefanishin-Piper fell during a welcoming ceremony the day after returning from the ISS.
Psychological adaptation to seemingly familiar earthly conditions can also be difficult. In 1973, astronaut Jack Lozma told reporters that he accidentally broke a bottle of aftershave in the first days after returning to Earth. He simply let go of the bubble, forgetting that it would fall and break, and would not start floating in weightlessness.
3. Use Pluto for Weight Loss
Pluto is not just a dwarf planet, but also great way lose weight. If on planet Earth a person's weight is, for example, 68 kg, then on Pluto he will weigh only 4.5 kg. The opposite effect exists on Jupiter - the same person will weigh 160.5 kg there.
The planet Mars, which mankind has not yet mastered, also "reduces" the weight of a person. The gravity of Mars is only 38% of Earth's gravity. That is, a person weighing 68 kg will "lose weight" on Mars up to 26 kg.
4. Gravity is not the same even on Earth
Since our planet is not an ideal sphere, its mass is also unevenly distributed. This means that its gravity is also uneven. For example, the most mysterious gravity anomaly is observed in the Hudson Bay in Canada. This area has a lower density than other regions of the planet due to the gradual melting of glaciers. The ice that covered this area of the Earth during the Ice Age has long melted, but the planet has not yet fully recovered. Due to the fact that the force of gravity on the area of this region is proportional to its mass, then at one time the ice "moved" part of the mass of the Earth. Any deformation of the earth's crust, like the movement of magma in the mantle, explains the decrease in gravity.
5. Without gravity, some bacteria would be more dangerous
For example, salmonella, which is the common cause of many food poisoning, becomes 3 times more deadly in the absence of gravity. Without gravity, they change their activity. Mice, which were specially fed in zero gravity with food contaminated with Salmonella, fell ill much faster, although they absorbed less bacteria compared to conditions on Earth.
6. Black holes in the centers of galaxies
Black holes are the most destructive objects in the universe. These celestial bodies are so named because even light does not fall into their gravitational field. In the center of our galaxy there is a huge black hole, which has a mass of 3 million suns, but does not pose any danger. But still, sometimes it makes itself felt: in 2008, a burst of energy emitted about 300 years ago reached our planet. And a few thousand years ago, a small amount of matter fell into this black hole, which led to another outbreak.
Space is the last frontier. Up to now, modern science has studied very little outer space. But from the little that we already know, there are extremely surprising things. So, 10 most interesting facts about space and astronauts.
This is a rather unpleasant, but strange fact.
In microgravity, astronauts don't use their legs to walk. Therefore, the skin on the legs begins to soften and flake off. Since it is difficult to wash things every day in space, astronauts wear the same underwear and socks for several days. Subsequently, these socks will need to be removed very carefully, otherwise the dead cells of the epithelium will break out into a weightless environment.
9. Space is polluted too
Few people know, but our planet from space does not look like it is shown in the films. The fact is that the beautiful view obscures space debris.
Space debris is any man-made object in Earth orbit that no longer serves useful purposes. Scientists estimate that today there are about 500,000 pieces of space debris, including particles from rockets and satellites and everyday objects such as the wrenches used during the construction of the International Space Station!
8. We're getting higher in space
It's all about the gravity of the Earth. On the surface of our planet, gravity compresses our spine a little. But at the space station, it weakens, and we can "grow" up to 5 cm. The same effect will be observed on any planet where the force of gravity is lower than that of the earth.
7. Into space in an hour
Officially, the boundary of outer space begins at an altitude of 100 kilometers in the exosphere. This mark is named "Pocket Line", after the American scientist Theodore von Karman. Therefore, if we could drive a car and drive it up, then space could be reached in less than an hour.
6. You can cry in space, but your tears won't fall
On board the International Space Station, water floats like bubbles or spheres. When tears are released, in microgravity they do not fall down, but accumulate around the eye. But that just sounds interesting. In fact, such a process is dangerous not only for health, but also for the life of an astronaut.
5. The Apollo 11 crew did not have insurance
Despite all the solvency of NASA, astronauts Neil Armstrong, Base Aldrin and Michael Collins were not even insured before the flight to the moon. Therefore, before takeoff, the future national heroes signed photographs, which could later be sold at an auction in the event of their death. Also on these photographs was the official seal of NASA and the date of the mission - July 16, 1969.
4. In space, metal sticks together
If you put two pieces of iron together in space, they will merge together. This effect is called cold welding. On Earth, due to the presence of oxygen and water molecules in our environment, this does not happen, but the method is used during some production processes... In space, due to the absence of any other atoms, metal particles cease to "understand" which piece they belong to, and are welded on their own.
3. The hottest planet is not the closest to the Sun
Despite the fact that Mercury is closest to the sun, it is not the hottest planet. There is no atmosphere on Mercury, so it heats up enough only in the daytime - up to +425 ° С, and at night nothing keeps the heat, so it becomes cold on the surface, almost up to -200 С. And the hottest planet is Venus. Its thick clouds literally absorb the temperature, forcing it to heat up to +500 ° C.
2. Goodbye old friend!
Our good neighbor and companion Moon is slowly leaving us. Despite the fact that there is optical illusion which makes the moon appear larger, each year it moves away from the Earth by 3.8 cm. This is caused by the tidal effects that the satellite itself creates. Consequently, our planet slows down its rotation by about 0.002 seconds every 1000 years. Therefore, one day the day will not be the usual 24 hours, but 25. When - count yourself.
1. If you put Saturn in water, it will not drown
Many people talk about the mass of the planets, about which is heavier - the Earth or the Sun. But in our system, there is one giant planet that will not even drown in water. Saturn's density is so low that if you put it in a giant glass of water, it will float. This is evidenced by the numbers: the actual density of Saturn is 0.687 g / cm3, and the density of water is 0.998 g / cm3. Of course, it will hardly ever be possible to verify this fact in practice.
