The influence of electricity on fruit and berry plants. Plants and their electrical potential
PHYSICS
BIOLOGY
Plants and their electrical potential.
Completed by: V.V. Markevich
GBOU OSH № 740 Moscow
Grade 9
Head: Kozlova Violetta Vladimirovna
physics and mathematics teacher
Moscow 2013
Content
Relevance
Goals and objectives of the work
Research methods
Significance of work
Introduction
Analysis of the studied literature on the topic "Electricity in life
plants "
Indoor air ionization
Study of damage currents in various plants
Experiment # 1 (with lemons)
Experiment # 2 (with an apple)
Experiment # 3 (with a plant leaf)
Experiments to Observe the Effect of Ionized Air on the Germination of Pea Seeds
Experiments to Observe the Effect of Ionized Air on Bean Seed Germination
Research methodology and technique
Study of the effect of an electric field on seed germination
conclusions
Conclusion
Literature
Chapter 1 Introduction
“As amazing as electrical phenomena are,
inherent in inorganic matter, they do not go
no comparison with those associated with
life processes ".
Michael Faraday
In this work, we turn to one of the most interesting and promising areas of research - the effect of physical conditions on plants.
Studying the literature on this issue, I learned that professor P.P. And cellular potentials are not that small. For example, in some algae they reach 0.15 V.
“If 500 pairs of pea halves are collected in a certain order in a series, then the final electric voltage will be 500 volts ... It's good that the chef does not know about the danger that threatens him when he prepares this special dish, and fortunately for him, the peas do not connect. into ordered series. " This statement by the Indian researcher J. Boss is based on a rigorous scientific experiment. He connected the inner and outer parts of the pea with a galvanometer and heated it to 60 ° C. At the same time, the device showed a potential difference of 0.5 V.
How does this happen? On what principle do living generators and batteries work? Eduard Trukhan, Candidate of Physical and Mathematical Sciences, Deputy Head of the Department of Living Systems of the Moscow Institute of Physics and Technology, believes that one of the most important processes occurring in a plant cell is the process of assimilation of solar energy, the process of photosynthesis.
So, if at that moment scientists manage to "pull apart" the positively and negatively charged particles in different directions, then, in theory, we will have at our disposal a wonderful living generator, for which water and sunlight would serve as fuel, and besides energy, it would also produce pure oxygen.
Perhaps such a generator will be created in the future. But to realize this dream, scientists will have to work hard: they need to select the most suitable plants, and maybe even learn how to artificially make chlorophyll grains, create some kind of membranes that would allow the separation of charges. It turns out that a living cell, storing electrical energy in natural capacitors - the intracellular membranes of special cell formations, mitochondria, then uses it to perform many works: building new molecules, drawing nutrients into the cell, regulating its own temperature ... And that's not all. With the help of electricity, the plant itself performs many operations: breathes, moves, grows.
Relevance
Already today, it can be argued that the study of the electrical life of plants is beneficial to agriculture. Even IV Michurin conducted experiments on the effect of electric current on the germination of hybrid seedlings.
Pre-sowing seed treatment is the most important element of agricultural technology, allowing to increase their germination, and ultimately - the yield of plants, and this is especially important in our not very long and warm summer.
Goals and objectives of the work
The aim of this work is to study the presence of bioelectric potentials in plants and to study the effect of an electric field on seed germination.
To achieve the research goal, it is necessary to solve the following tasks :
Study of the main provisions concerning the doctrine of bioelectric potentials and the influence of an electric field on the vital activity of plants.
Carrying out experiments to detect and observe damage currents in various plants.
Carrying out experiments to observe the effect of an electric field on seed germination.
Research methods
To accomplish the research tasks, theoretical and practical methods are used. Theoretical method: search, study and analysis of scientific and popular science literature on this issue. Practical research methods are used: observation, measurement, experiments.
Significance of work
The material of this work can be used in physics and biology lessons, since this important issue is not covered in textbooks. And the method of conducting experiments - as a material for the practical lessons of the elective course.
Chapter 2 Analysis of the studied literature
The history of research into the electrical properties of plants
One of the characteristic features of living organisms is the ability to irritate.
Charles Darwinattached great importance to the irritability of plants. He studied in detail the biological characteristics of insectivorous representatives of the plant world, which are distinguished by high sensitivity, and presented the results of the research in the wonderful book "On Insectivorous Plants", published in 1875. In addition, various plant movements attracted the attention of the great naturalist. Taken together, all the studies suggested that the plant organism is remarkably similar to the animal.
The widespread use of electrophysiological methods has allowed animal physiologists to achieve significant progress in this area of knowledge. It was found that electric currents (biocurrents) constantly arise in the organisms of animals, the spread of which leads to motor reactions. C. Darwin suggested that similar electrical phenomena also take place in the leaves of insectivorous plants, which have a rather pronounced ability to move. However, he himself did not test this hypothesis. At his request, experiments with the Venus flytrap plant were carried out in 1874 by a physiologist at the University of OxfordBurdan Sanderson... Having connected a leaf of this plant to a galvanometer, the scientist noted that the arrow immediately deviated. This means that electrical impulses arise in the living leaf of this insectivorous plant. When the researcher irritated the leaves by touching the bristles located on their surface, the galvanometer needle deflected in the opposite direction, as in the experiment with the animal's muscle.
German physiologistHermann Munch, who continued his experiments, in 1876 came to the conclusion that the leaves of the Venus flytrap are electromotorically similar to the nerves, muscles and electrical organs of some animals.
In Russia, electrophysiological methods were usedN.K. Levakovskyto study the phenomena of irritability in bashful mimosa. In 1867 he published a book entitled "On the movement of irritable plant organs." In the experiments of N.K. Levakovsky, the strongest electrical signals were observed in those specimensmimosa which responded most vigorously to external stimuli. If mimosa is quickly killed by heating, then the dead parts of the plant do not produce electrical signals. The author also observed the appearance of electrical impulses in stamensthistle and thistle, in the petioles of sundew leaves. It was subsequently found that
Bioelectric potentials in plant cells
Plant life is associated with moisture. Therefore, the electrical processes in them are most fully manifested in the normal mode of humidification and attenuate during wilting. This is due to the exchange of charges between the liquid and the walls of the capillary vessels during the flow of nutrient solutions through the capillaries of plants, as well as to the processes of ion exchange between cells and the environment. The most important for vital activity electric fields are excited in cells.
So, we know that ...
Pollen carried by the wind is negatively charged ‚Approaching in size to the charge of dust particles during dust storms. In the vicinity of plants losing pollen, the ratio between positive and negative light ions changes sharply, which favorably affects the further development of plants.
In the practice of spraying pesticides in agriculture, it was found thatchemicals with a positive charge are deposited to a greater extent on beets and apple trees, and chemicals with a negative charge are deposited on lilacs.
One-sided illumination of a leaf excites an electrical potential difference between its illuminated and unlit areas and the petiole, stem and root. This potential difference expresses the plant's response to changes in its body associated with the beginning or termination of the process of photosynthesis.
Germination of seeds in a strong electric field (e.g. near the corona electrode)leads to change the height and thickness of the stem and the density of the crown of developing plants. this occurs mainly due to the redistribution in the plant organism under the influence of the external electric field of the space charge.
The damaged place in plant tissues is always charged negatively relatively intact areas, and the dying areas of plants acquire a negative charge in relation to areas growing under normal conditions.
Charged seeds of cultivated plants have a relatively high electrical conductivity and therefore quickly lose their charge. Weed seeds are closer in their properties to dielectrics and can retain a charge for a long time. This is used to separate crop seeds from weeds on the conveyor.
Significant potential differences in the plant organism cannot be excited Because plants do not have a specialized electrical organ. Therefore, there is no “tree of death” among plants, which could kill living beings with its electrical power.
Effect of atmospheric electricity on plants
One of the characteristic features of our planet is the presence of a constant electric field in the atmosphere. The person does not notice him. But the electrical state of the atmosphere is not indifferent to him and other living beings that inhabit our planet, including plants. Above the Earth at an altitude of 100-200 km, there is a layer of positively charged particles - the ionosphere.
This means that when you walk along a field, street, square, you move in an electric field, you inhale electric charges.
The influence of atmospheric electricity on plants has been studied since 1748 by many authors. This year Abbot Nolet reported on experiments in which he electrified plants by placing them under charged electrodes. He observed the acceleration of germination and growth. Grandieu (1879) observed that plants that were not exposed to atmospheric electricity, as they were placed in a wire mesh grounded box, showed a weight reduction of 30-50% compared to control plants.
Lemström (1902) exposed plants to the action of air ions, placing them under a wire equipped with points and connected to a high voltage source (1 m above ground level, ion current 10-11 - 10 -12 A / cm 2 ), and he found an increase in weight and length of more than 45% (e.g. carrots, peas, cabbage).
The fact that plant growth was accelerated in an atmosphere with an artificially increased concentration of positive and negative small ions was recently confirmed by Krueger and his collaborators. They found that oat seeds reacted to positive as well as negative ions (concentration of about 10 4 ions / cm 3 ) an increase of 60% in the total length and an increase in fresh and dry weight of 25-73%. Chemical analysis of the aerial parts of the plants revealed an increase in the content of protein, nitrogen and sugar. In the case of barley, had an even greater increase (by about 100%) in total elongation; the increase in fresh weight was not large, but there was a marked increase in dry weight, which was accompanied by corresponding increases in protein, nitrogen and sugar.
Experiments with plant seeds were also carried out by Warden. He found that the germination of green beans and green peas became earlier with increasing levels of ions of either polarity. The final percentage of germinated seeds was lower with negative ionization compared to the control group; germination in the positively ionized group and the control group was the same. As the seedlings grew, the control and positively ionized plants continued to grow, while the negatively ionized plants mostly wither and die.
Influence in recent years has been a strong change in the electrical state of the atmosphere; different regions of the Earth began to differ from each other in the ionized state of the air, which is due to its dustiness, gas content, etc. The electrical conductivity of air is a sensitive indicator of its purity: the more foreign particles in the air, the more ions settle on them and, therefore, the electrical conductivity of the air becomes less.
So, in Moscow, 1 cm 3 of air contains 4 negative charges, in St. Petersburg - 9 such charges, in Kislovodsk, where the standard of air purity is 1.5 thousand particles, and in the south of Kuzbass in the mixed forests of the foothills, the number of these particles reaches up to 6 thousand. This means that where there are more negative particles, it is easier to breathe, and where there is dust, a person gets less of them, since dust particles settle on them.
It is well known that near fast flowing water the air refreshes and invigorates. It contains a lot of negative ions. Back in the 19th century, it was determined that larger drops in splashes of water are positively charged, and smaller drops are negatively charged. As large droplets settle faster, negatively charged small droplets remain in the air.
On the contrary, the air in confined spaces with an abundance of all kinds of electromagnetic devices is saturated with positive ions. Even a relatively short stay in such a room leads to lethargy, drowsiness, dizziness and headaches.
Chapter 3 Research methodology
Study of damage currents in various plants.
Tools and materials3 lemons, apple, tomato, plant leaf;
3 shiny copper coins;
3 galvanized screws;
wires, preferably with clamps at the ends;
small knife;
several sticky notes;
low-voltage LED 300mV;
nail or awl;
multimeter.
Experiments to detect and observe damage currents in plants
Technique for performing experiment No. 1. Current in lemons.
First of all, all the lemons were crushed. This is done so that juice appears inside the lemon.A galvanized screw was screwed into the lemons about a third of its length. Using a knife, carefully cut out a small strip in the lemon - 1/3 of its length. A copper coin was inserted into the slot in the lemon so that half of it remained outside.
They inserted screws and coins in the other two lemons in the same way. Then they connected the wires and clamps, connected the lemons in such a way that the screw of the first lemon was connected to the coin of the second, etc. We connected the wires to a coin from the first lemon and a screw from the last one. The lemon works like a battery: the coin is the positive (+) pole and the screw is the negative (-) pole. Unfortunately, this is a very weak energy source. But it can be enhanced by combining several lemons.
We connected the positive pole of the diode to the positive pole of the battery, connected the negative pole. The diode is on !!!
Over time, the voltage across the poles of the lemon battery will decrease. Noticed how long the lemon battery lasts. After a while, the lemon darkened near the screw. If you remove the screw and insert it (or a new one) in another place of the lemon, you can partially extend the battery life. You can also try to wrinkle the battery by moving the coins from time to time.
We did an experiment with a lot of lemons. The diode became brighter. The battery now lasts longer.
Larger pieces of zinc and copper were used.
We took a multimeter, measured the battery voltage.
Technique for performing experiment No. 2. Current in apples.
The apple was cut in half and cored.
If both electrodes, assigned to the multimeter, are applied to the outside of the apple (peel), the multimeter will not detect a potential difference.
One electrode is moved to the inside of the pulp, and the multimeter will note the occurrence of a fault current.
Let's experiment with vegetables - tomatoes.
The measurement results were placed in a table.
the other is in the pulp of an apple
0.21V
Electrodes in the pulp of a cut apple
0.05V
Electrodes in tomato pulp
0.02V
Technique for performing experiment No. 3. Current in the cut stem.
Cut off a plant leaf with a stem.
The damage currents were measured at the cut stem at different distances between the electrodes.
The measurement results were placed in a table.
RESULTS OF THE STUDY
In any plant, the occurrence of electrical potentials can be detected.
Study of the effect of the electric field on seed germination.
Tools and materials
pea seeds, beans;
Petri dishes;
air ionizer;
clock;
water.
Experiments to observe the effect of ionized air on seed germination
Experiment 1 technique
The ionizer was switched on daily for 10 minutes.
Germination of 8 seeds (5 did not sprout)
10.03.09
Sprouts enlargement
at 10 seeds (3 did not germinate)
Sprouts enlargement
11.03.09
Sprouts enlargement
at 10 seeds (3 did not germinate)
Sprouts enlargement
12.03.09
Sprouts enlargement
Sprouts enlargement
Germination of 3 seeds(4 did not germinate)
11.03.09
Increased seed sprouts
Germination of 2 seeds
(2 did not sprout)
12.03.09
Increased seed sprouts
Increased seed sprouts
Research results
The experimental results indicate that seed germination is faster and more successful under the action of the electric field of the ionizer.
The procedure for performing experiment No. 2
For the experiment, they took seeds of peas and beans, soaked them in Petri dishes and placed them in different rooms with the same illumination and room temperature. In one of the rooms, an air ionizer was installed - a device for artificial ionization of air.
The ionizer was switched on daily for 20 minutes.
Every day we moistened the seeds of peas, beans and watched when the seeds hatch.
Germination of 6 seeds Germination of 9 seeds
(3 did not germinate)
19.03.09
Germination of 2 seeds
(4 did not germinate)
Increased seed sprouts
20.03.09
Increased seed sprouts
Increased seed sprouts
21.03.09
Increased seed sprouts
Increased seed sprouts
Experienced cup(with treated seeds)
Control cup
15.03.09
Soaking the seeds
Soaking the seeds
16.03.09
Swelling of seeds
Swelling of seeds
17.03.09
Without changes
Without changes
18.03.09
Germination of 3 seeds
(5 did not sprout)
Germination of 4 seeds
(4 did not germinate)
19.03.09
Germination of 3 seeds
(2 did not sprout)
Germination of 2 seeds
(2 did not sprout)
20.03.09
Sprouts enlargement
Germination of 1 seed
(1 did not germinate)
21.03.09
Sprouts enlargement
Sprouts enlargement
Research results
The experimental results indicate that a longer exposure to the electric field had a negative effect on seed germination. They sprouted later and not as successfully.
The procedure for performing experiment No. 3
For the experiment, they took seeds of peas and beans, soaked them in Petri dishes and placed them in different rooms with the same illumination and room temperature. In one of the rooms, an air ionizer was installed - a device for artificial ionization of air.
The ionizer was switched on daily for 40 minutes.
Every day we moistened the seeds of peas, beans and watched when the seeds hatch.
The timing of the experiments was placed in tables
(4 did not germinate)
05.04.09
Without changes
Sprouts enlargement
06.04.09
Germination of 2 seeds
(10 did not sprout)
Sprouts enlargement
07.04.09
Sprouts enlargement
Sprouts enlargement
Without changesGermination of 3 seeds
(4 did not germinate)
06.04.09
Germination of 2 seeds
(5 did not sprout)
Germination of 2 seeds
(2 did not sprout)
07.04.09
Sprouts enlargement
Sprouts enlargement
Research results
The experimental results indicate that a longer exposure to the electric field had a negative effect on seed germination. Their germination decreased markedly.
CONCLUSIONS
In any plant, the occurrence of electrical potentials can be detected.
The electric potential depends on the type and size of plants, on the distance between the electrodes.
Seed treatment with an electric field within reasonable limits leads to an acceleration of the process of seed germination and a more successful germination..
After processing and analysis of experimental and control samples, a preliminary conclusion can be drawn - an increase in the time of irradiation with an electrostatic field is depressing, since the quality of seed germination is lower with an increase in the ionization time.
Chapter 4 Conclusion
Currently, numerous studies of scientists are devoted to the influence of electric currents on plants. The influence of electric fields on plants is still being thoroughly studied.
Research carried out at the Institute of Plant Physiology made it possible to establish the relationship between the intensity of photosynthesis and the value of the difference in electrical potentials between the earth and the atmosphere. However, the mechanism underlying these phenomena has not yet been investigated.
Starting the research, we set ourselves the goal: to determine the influence of the electric field on plant seeds.
After processing and analysis of experimental and control samples, a preliminary conclusion can be drawn - an increase in the time of exposure to an electrostatic field is depressing. We believe that this work is not finished, since only the first results have been obtained.
Further research on this issue can be continued in the following areas:
Influenced whether the treatment of seeds with an electric field for the further growth of plants?
Chapter 5 REFERENCES
Bogdanov K. Yu. Physicist visiting a biologist. - Moscow: Nauka, 1986.144 p.
Vorotnikov A.A. Physics for the young. - M: Harvest, 1995-121s.
Katz Ts.B. Biophysics in physics lessons. - M: Education, 1971-158s.
Perelman Ya.I. Entertaining physics. - M: Science, 1976-432s.
Artamonov V.I. Entertaining plant physiology. - M .: Agropromizdat, 1991.
Arabadzhi V.I., The Riddles of Plain Water.- M .: "Knowledge", 1973.
http: // www .pereplet .ru / obrazovanie / stsoros /163.html
http: // www .npl -rez .ru / litra / bios .htm
http: // www.ionization.ru
Global capacitor
In nature, there is a completely unique alternative energy source, environmentally friendly, renewable, easy to use, which is still not used anywhere. This source is the atmospheric electrical potential.
Our planet is electrically like a spherical capacitor, charged to about 300,000 volts. The inner sphere - the surface of the Earth - is negatively charged, the outer sphere - the ionosphere - positively. The Earth's atmosphere serves as an insulator (Fig. 1).
Ionic and convective condenser leakage currents constantly flow through the atmosphere, reaching many thousands of amperes. But despite this, the potential difference between the capacitor plates does not decrease.
This means that in nature there is a generator (G), which constantly replenishes the leakage of charges from the capacitor plates. Such a generator is the Earth's magnetic field., which rotates with our planet in the flow of the solar wind.
To use the energy of this generator, you need to somehow connect an energy consumer to it.
Connecting to the negative pole - Earth - is easy. To do this, it is enough to make a reliable grounding. Connecting to the positive pole of the generator - the ionosphere - is a complex technical problem, and we will deal with it.
As with any charged capacitor, there is an electric field in our global capacitor. The intensity of this field is distributed very unevenly along the height: it is maximum at the surface of the Earth and is approximately 150 V / m. With height, it decreases approximately according to the exponential law and at an altitude of 10 km is about 3% of the value at the Earth's surface.
Thus, almost all of the electric field is concentrated in the lower layer of the atmosphere, near the surface of the Earth. Vector of tension e. field of the Earth E is directed in the general case downward. In our reasoning, we will use only the vertical component of this vector. The electric field of the Earth, like any electric field, acts on charges with a certain force F, which is called the Coulomb force. If you multiply the amount of charge by the strength of the email. field at this point, then we get just the value of the Coulomb force Fkul .. This Coulomb force pushes positive charges down to the ground, and negative charges up to the clouds.
Conductor in an electric field
We will install a metal mast on the surface of the Earth and ground it. An external electric field will instantly begin to move negative charges (conduction electrons) up to the top of the mast, creating an excess of negative charges there. And the excess of negative charges at the top of the mast will create its own electric field directed towards the external field. There comes a moment when these fields become equal in magnitude, and the movement of electrons stops. This means that in the conductor from which the mast is made, the electric field is zero.
This is how the laws of electrostatics work.
Let's put the height of the mast h = 100 m., The average tension along the height of the mast is Еср. = 100 V / m.
Then the potential difference (e.m.f.) between the Earth and the top of the mast will be numerically equal to: U = h * Eav. = 100 m * 100 V / m = 10,000 volts. (one)
This is a very real potential difference that can be measured. True, it will not be possible to measure it with an ordinary voltmeter with wires - exactly the same emf will appear in the wires as in the mast, and the voltmeter will show 0. This potential difference is directed opposite to the vector of the strength E of the Earth's electric field and tends to push the conduction electrons from the top of the mast up into the atmosphere. But this does not happen, electrons cannot leave the conductor. The electrons do not have enough energy to leave the conductor from which the mast is made. This energy is called the work function of the electron from the conductor and for most metals it is less than 5 electron volts - a very insignificant value. But an electron in a metal cannot acquire such energy between collisions with the crystal lattice of the metal and therefore remains on the surface of the conductor.
The question arises: what happens to the conductor if we help the excess charges at the top of the mast to leave this conductor?
The answer is simple: the negative charge at the top of the mast will decrease, the external electric field inside the mast will no longer be compensated and will begin to move the conduction electrons up to the top end of the mast again. This means that current will flow through the mast. And if we manage to constantly remove excess charges from the top of the mast, there will be a constant current flowing through it. Now we just have to cut the mast in any place convenient for us and turn on the load (energy consumer) there - and the power plant is ready.
Figure 3 shows a schematic diagram of such a power plant. Under the influence of the Earth's electric field, conduction electrons from the ground move along the mast through the load and then up the mast to the emitter, which frees them from the metal surface of the mast top and sends them in the form of ions to float freely through the atmosphere. The Earth's electric field, in full accordance with Coulomb's law, raises them up until they are neutralized on their way by positive ions, which always descend from the ionosphere under the action of the same field.
Thus, we have closed the electrical circuit between the plates of the global electrical capacitor, which in turn is connected to the generator G, and included an energy consumer (load) in this circuit. One important question remains to be resolved: how to remove excess charges from the top of the mast?
Emitter design
The simplest emitter is a flat disc of sheet metal with many needles located around its circumference. It is "mounted" on a vertical axis and rotated.
When the disk rotates, the incoming moist air strips electrons from its needles and thus frees them from the metal.
A power plant with a similar emitter already exists. True, no one uses her energy, they are fighting with her.
This is a helicopter carrying a metal structure on a long metal sling when erecting tall buildings. There are all the elements of the power plant shown in Fig. 3, with the exception of the energy consumer (load). The emitter is the rotor blades of the helicopter, which are blown by a stream of moist air, the mast is a long steel sling with a metal structure. And the workers who install this structure in place know perfectly well that it is impossible to touch it with bare hands - it will "shock you". And indeed, at this moment they become a load in the power plant circuit.
Of course, other emitter designs are possible, more efficient, complex, based on different principles and physical effects, see Fig. 4-5.
The emitter in the form of a finished product does not exist now. Everyone interested in this idea is forced to independently design their own emitter.
To help such creative people, the author gives below his considerations on the design of the emitter.
The most promising are the following emitter designs.
The first version of the emitter
The water molecule has a well-pronounced polarity and can easily capture a free electron. If a negatively charged metal plate is blown with steam, then the steam will capture free electrons from the surface of the plate and carry them away. The emitter is a slotted nozzle, along which an insulated electrode A is placed and to which a positive potential is supplied from a source I. Electrode A and the sharp edges of the nozzle form a small charged capacitance. Free electrons are collected at the sharp edges of the nozzle under the influence of the positive insulated electrode A. The vapor passing through the nozzle strips the electrons from the edges of the nozzle and carries them into the atmosphere. In fig. 4 shows a longitudinal section of this structure. Since electrode A is isolated from the external environment, the current in the circuit of the emf source no. And this electrode is needed here only in order to create a strong electric field in this gap together with the sharp edges of the nozzle and to concentrate conduction electrons at the edges of the nozzle. Thus, electrode A with a positive potential is a kind of activating electrode. By changing the potential on it, you can achieve the desired value of the emitter current.
A very important question arises - how much steam needs to be supplied through the nozzle and will it not turn out that all the energy of the station will have to be spent on converting water into steam? Let's do a little counting.
One grammolecule of water (18 ml) contains 6.02 * 1023 water molecules (Avogadro's number). The charge of one electron is 1.6 * 10 (- 19) Coulomb. Multiplying these values, we get that 96,000 Coulombs of electric charge can be placed on 18 ml of water, and more than 5,000,000 Coulombs can be placed on 1 liter of water. This means that at a current of 100 A, one liter of water is enough to operate the installation for 14 hours. To convert this amount of water into steam, a very small percentage of the generated energy is required.
Of course, attaching an electron to each water molecule is hardly a feasible task, but here we have determined the limit to which one can constantly approach, improving the design of the device and technology.
In addition, calculations show that it is energetically more advantageous to blow humid air through the nozzle, rather than steam, by adjusting its humidity within the required limits.
The second version of the emitter
A metal vessel with water is installed at the top of the mast. The vessel is connected to the metal of the mast by reliable contact. A glass capillary tube is installed in the middle of the vessel. The water level in the tube is higher than in the vessel. This creates the electrostatic effect of the tip - in the upper part of the capillary tube, the maximum concentration of charges and the maximum strength of the electric field are created.
Under the action of an electric field, the water in the capillary tube will rise and will be sprayed into small droplets, carrying away the negative charge. At a certain small current strength, the water in the capillary tube will boil, and the steam will already carry away the charges. This should increase the emitter current.
Several capillary tubes can be installed in such a vessel. How much water is required - see calculations above.
The third embodiment of the emitter. Spark emitter.
When the spark gap breaks down, a cloud of conduction electrons pops up from the metal together with the spark.
Figure 5 shows a schematic diagram of a spark emitter. From the high-voltage pulse generator, negative pulses are fed to the mast, and positive pulses to the electrode, which forms a spark gap with the top of the mast. It turns out something similar to an automobile spark plug, but the device is much simpler.
The high-voltage pulse generator is fundamentally not much different from the usual Chinese-made household gas lighter powered by one finger-type battery.
The main advantage of such a device is the ability to regulate the emitter current using the discharge frequency, the size of the spark gap, you can make several spark gaps, etc.
The pulse generator can be installed in any convenient location, not necessarily at the top of the mast.
But there is one drawback - spark discharges create radio interference. Therefore, the top of the mast with spark gaps must be shielded with a cylindrical mesh, necessarily insulated from the mast.
The fourth version of the emitter
Another possibility is to create an emitter based on the principle of direct emission of electrons from the emitter material. This requires a material with a very low electron work function. Such materials have existed for a long time, for example, barium oxide paste - 0.99 eV. Perhaps there is something better now.
Ideally, this should be a room-temperature superconductor (RTSC), which does not yet exist in nature. But according to various reports, he should appear soon. All hope here is in nanotechnology.
It is enough to place a piece of KTSC on the top of the mast - and the emitter is ready. Passing through the superconductor, the electron does not encounter resistance and very quickly acquires the energy necessary to leave the metal (about 5 eV.)
And one more important note. According to the laws of electrostatics, the intensity of the Earth's electric field is highest on the heights - on the tops of hills, hills, mountains, etc. In the lowlands, depressions and depressions it is minimal. Therefore, it is better to build such devices on the highest places and away from tall buildings, or install them on the roofs of the tallest buildings.
It is also a good idea to use a balloon to lift the conductor. The emitter, of course, needs to be mounted on top of the balloon. In this case, it is possible to obtain a sufficiently large potential for spontaneous emission of electrons from the metal, giving it the form of negrium, and, therefore, no complex emitters are required in this case.
There is another good opportunity to get an emitter. The industry uses electrostatic painting of metal. The sprayed paint, flying out of the sprayer, carries an electric charge, due to which it settles on the metal to be painted, to which a charge of the opposite sign is applied. The technology has been worked out.
Such a device, which charges the sprayed paint, is precisely the real emitter of e-mail. charges. All that remains is to adapt it to the installation described above and replace the paint with water, if necessary, if necessary.
It is possible that the moisture always contained in the air will be sufficient for the emitter to work.
It is possible that there are other similar devices in the industry that can be easily turned into an emitter.
conclusions
As a result of our actions, we connected the energy consumer to the global generator of electrical energy. We connected to the negative pole - the Earth - using an ordinary metal conductor (ground), and to the positive pole - the ionosphere - using a very specific conductor - convective current. Convective currents are electric currents caused by the ordered transport of charged particles. They are common in nature. These are ordinary convective ascending jets, which carry negative charges to the clouds, and these are tornadoes (tornadoes). which drag the cloudy mass strongly charged with positive charges to the ground, these are the ascending air currents in the intertropical convergence zone, which carry away a huge amount of negative charges to the upper troposphere. And such currents reach very high values.
If we create a sufficiently efficient emitter that can release from the top of a mast (or several masts), say, 100 coulombs of charges per second (100 amperes), then the power of the power plant we have built will be equal to 1,000,000 watts or 1 megawatt. Quite decent power!
Such an installation is indispensable in remote settlements, at meteorological stations and other places remote from civilization.
From the above, the following conclusions can be drawn:
The energy source is extremely easy and convenient to use.
As a result, we get the most convenient type of energy - electricity.
The source is environmentally friendly: no emissions, no noise, etc.
The installation is extremely easy to manufacture and operate.
The exceptional cheapness of the energy received and a host of other advantages.
The Earth's electric field is subject to fluctuations: in winter it is stronger than in summer, it reaches its maximum daily at 19:00 GMT, and also depends on the state of the weather. But these fluctuations do not exceed 20% of its average value.
In some rare cases, under certain weather conditions, the strength of this field can increase several times.
During a thunderstorm, the electric field changes over a wide range and can change direction to the opposite, but this occurs in a small area directly under the thunderstorm cell.
Kurilov Yuri Mikhailovich
The biological influence of electric and magnetic fields on the organism of humans and animals has been studied a lot. The observed effects, if they occur, are still not clear and difficult to define, so this topic remains relevant.
Magnetic fields on our planet have a dual origin - natural and anthropogenic. Natural magnetic fields, the so-called magnetic storms, originate in the Earth's magnetosphere. Anthropogenic magnetic disturbances cover a smaller territory than natural ones, but their manifestation is much more intense, and, therefore, brings more tangible damage. As a result of technical activity, a person creates artificial electromagnetic fields, which are hundreds of times stronger than the natural magnetic field of the Earth. Sources of anthropogenic radiation are: powerful radio transmitting devices, electrified vehicles, power lines (Fig. 2.1).
One of the most powerful pathogens of electromagnetic waves is currents of industrial frequency (50 Hz). So, the electric field strength directly under the power line can reach several thousand volts per meter of soil, although due to the property of reducing the tension by the soil, already at a distance of 100 m from the line, the intensity drops sharply to several tens of volts per meter.
Studies of the biological effect of an electric field have found that even at a strength of 1 kV / m, it has an adverse effect on the human nervous system, which in turn leads to disruption of the endocrine apparatus and metabolism in the body (copper, zinc, iron and cobalt), disrupts physiological functions: heart rate, blood pressure, brain activity, metabolic processes and immune activity.
Since 1972, publications have appeared in which the effect on humans and animals of electric fields with intensities of more than 10 kV / m has been considered.
Magnetic field strength is proportional to current and inversely proportional to distance; the strength of the electric field is proportional to the voltage (charge) and inversely proportional to the distance. The parameters of these fields depend on the voltage class, design features and geometrical dimensions of the high-voltage transmission line. The emergence of a powerful and extended source of the electromagnetic field leads to a change in those natural factors under which the ecosystem was formed. Electric and magnetic fields can induce surface charges and currents in the human body (Fig. 2.2). Research has shown,
that the maximum current in the human body, induced by the electric field, is much higher than the current caused by the magnetic field. So, the harmful effect of a magnetic field is manifested only when its intensity is about 200 A / m, which happens at a distance of 1-1.5 m from the line phase wires and is dangerous only for maintenance personnel when working under voltage. This circumstance made it possible to draw a conclusion about the absence of the biological effect of magnetic fields of industrial frequency on people and animals under power lines.Thus, the electric field of power lines is the main biologically effective factor of an extended power transmission, which can turn out to be a barrier to the migration of movement of various types of water and terrestrial fauna.
Based on the design features of the power transmission (wire sagging), the greatest influence of the field is manifested in the middle of the span, where the tension for super- and ultra-high voltage lines at the level of a person's height is 5-20 kV / m and higher, depending on the voltage class and line design (Fig. 1.2). At the supports, where the height of the suspension of the wires is greatest and the shielding effect of the supports affects, the field strength is the smallest. Since people, animals, transport can be under the wires of power lines, it becomes necessary to assess the possible consequences of a long and short-term stay of living beings in an electric field of various strengths. The most sensitive to electric fields are ungulates and humans in shoes that insulate them from the ground. The animal's hoof is also a good insulator. In this case, the induced potential can reach 10 kV, and the current pulse through the body when it touches a grounded object (bush branch, blade of grass) is 100-200 μA. Such impulses of current are safe for the body, but unpleasant sensations force ungulates to avoid high-voltage power lines in the summer.
In the action of an electric field on a person, the currents flowing through his body play a dominant role. This is determined by the high conductivity of the human body, where organs with blood and lymph circulating in them predominate. At present, experiments on animals and human volunteers have established that the current density with a conductivity of 0.1 μA / cm 2 and below does not affect the work of the brain, since the pulsed biocurrents, usually flowing in the brain, significantly exceed the density of such a conduction current. At /> 1 μA / cm 2, a flickering of light circles is observed in the eyes of a person, higher current densities already capture the threshold values of stimulation of sensory receptors, as well as nerve and muscle cells, which leads to the appearance of fright and involuntary motor reactions. In the case of a person touching objects isolated from the ground in the zone of an electric field of significant intensity, the current density in the heart zone strongly depends on the state of the underlying conditions (type of footwear, soil condition, etc.), but it can already reach these values. At a maximum current corresponding to Etah== l5 kV / m (6.225 mA); a known fraction of this current flowing through the head region (about 1/3) and the head area (about 100 cm 2) current density j<0,1 мкА/см 2 , что и подтверждает допустимость принятой в СССР напряженности 15 кВ/м под проводами воздушной линии.
For human health, the problem is to determine the relationship between the density of the current induced in the tissues and the magnetic induction of the external field, IN. Calculation of current density
complicated by the fact that its exact path depends on the distribution of the conductance y in the tissues of the body.
So, the specific conductivity of the brain is determined by = 0.2 cm / m, and the heart muscle == 0.25 cm / m. If we take the radius of the head 7.5 cm and the radius of the heart 6 cm, then the product R turns out to be the same in both cases. Therefore, one can give one representation for the current density at the periphery of the heart and brain.
It has been determined that the magnetic induction, safe for health, is about 0.4 mT at a frequency of 50 or 60 Hz. In magnetic fields (from 3 to 10 mT; f= 10-60 Hz), the appearance of light flickers, similar to those that occur when pressing on the eyeball, was observed.
The density of the current induced in the human body by an electric field with a strength value E, is calculated like this:
with different coefficients k for the area of the brain and heart. Meaning k=3 10 -3 cm / Hzm. According to German scientists, the field strength at which hair vibration is felt by 5% of the men tested is 3 kV / m, and for 50% of the men tested, it is 20 kV / m. Currently, there is no evidence that the sensations caused by the action of the field create any adverse effect. As for the relationship between current density and biological influence, four areas can be distinguished, presented in table. 2.1
The last area of the current density value refers to exposure times of the order of one cardiac cycle, i.e. approximately 1 s for a person For shorter exposures, the threshold values are higher. To determine the threshold value of the field strength, physiological studies were performed on humans in laboratory conditions at a strength of 10 to 32 kV / m. It was found that at a voltage of 5 kV / m 80%
Table 2.1
people do not experience pain during discharges in case of touching grounded objects. It is this value that was adopted as the standard when working in electrical installations without the use of protective equipment. Dependence of the permissible time of a person's stay in an electric field with intensity E more than the threshold is approximated by the equation
Fulfillment of this condition ensures self-restoration of the physiological state of the body during the day without residual reactions and functional or pathological changes.
Let's get acquainted with the main results of studies of the biological effects of electric and magnetic fields carried out by Soviet and foreign scientists.
Markevich V.V.
In this work, we turn to one of the most interesting and promising areas of research - the effect of physical conditions on plants.
Studying the literature on this issue, I learned that professor P.P. And cellular potentials are not that small.
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PHYSICS
BIOLOGY
Plants and their electrical potential.
Completed by: V.V. Markevich
GBOU OSH № 740 Moscow
Grade 9
Head: Kozlova Violetta Vladimirovna
physics and mathematics teacher
Moscow 2013
- Introduction
- Relevance
- Goals and objectives of the work
- Research methods
- Significance of work
- Analysis of the studied literature on the topic "Electricity in life
plants "
- Indoor air ionization
- Research methodology and technique
- Study of damage currents in various plants
- Experiment # 1 (with lemons)
- Experiment # 2 (with an apple)
- Experiment # 3 (with a plant leaf)
- Study of the effect of an electric field on seed germination
- Experiments to Observe the Effect of Ionized Air on the Germination of Pea Seeds
- Experiments to Observe the Effect of Ionized Air on Bean Seed Germination
- conclusions
- Conclusion
- Literature
Introduction
“As amazing as electrical phenomena are,
inherent in inorganic matter, they do not go
no comparison with those associated with
life processes ".
Michael Faraday
In this work, we turn to one of the most interesting and promising areas of research - the effect of physical conditions on plants.
Studying the literature on this issue, I learned that professor P.P. And cellular potentials are not that small. For example, in some algae they reach 0.15 V.
“If 500 pairs of pea halves are collected in a certain order in a series, then the final electric voltage will be 500 volts ... It's good that the chef does not know about the danger that threatens him when he prepares this special dish, and fortunately for him, the peas do not connect. into ordered series. "This statement by the Indian researcher J. Boss is based on a rigorous scientific experiment. He connected the inner and outer parts of the pea with a galvanometer and heated it to 60 ° C. At the same time, the device showed a potential difference of 0.5 V.
How does this happen? On what principle do living generators and batteries work? Eduard Trukhan, Candidate of Physical and Mathematical Sciences, Deputy Head of the Department of Living Systems of the Moscow Institute of Physics and Technology, believes that one of the most important processes occurring in a plant cell is the process of assimilation of solar energy, the process of photosynthesis.
So, if at that moment scientists manage to "pull apart" the positively and negatively charged particles in different directions, then, in theory, we will have at our disposal a wonderful living generator, for which water and sunlight would serve as fuel, and besides energy, it would also produce pure oxygen.
Perhaps such a generator will be created in the future. But to realize this dream, scientists will have to work hard: they need to select the most suitable plants, and maybe even learn how to artificially make chlorophyll grains, create some kind of membranes that would allow the separation of charges. It turns out that a living cell, storing electrical energy in natural capacitors - the intracellular membranes of special cell formations, mitochondria, then uses it to perform many works: building new molecules, drawing nutrients into the cell, regulating its own temperature ... And that's not all. With the help of electricity, the plant itself performs many operations: breathes, moves, grows.
Relevance
Already today, it can be argued that the study of the electrical life of plants is beneficial to agriculture. Even IV Michurin conducted experiments on the effect of electric current on the germination of hybrid seedlings.
Pre-sowing seed treatment is the most important element of agricultural technology, allowing to increase their germination, and ultimately - the yield of plants, and this is especially important in our not very long and warm summer.
Goals and objectives of the work
The aim of this work is to study the presence of bioelectric potentials in plants and to study the effect of an electric field on seed germination.
To achieve the research goal, it is necessary to solve the following tasks :
- Study of the main provisions concerning the doctrine of bioelectric potentials and the influence of an electric field on the vital activity of plants.
- Carrying out experiments to detect and observe damage currents in various plants.
- Carrying out experiments to observe the effect of an electric field on seed germination.
Research methods
To accomplish the research tasks, theoretical and practical methods are used. Theoretical method: search, study and analysis of scientific and popular science literature on this issue. Practical research methods are used: observation, measurement, experiments.
Significance of work
The material of this work can be used in physics and biology lessons, since this important issue is not covered in textbooks. And the method of conducting experiments - as a material for the practical lessons of the elective course.
Analysis of the studied literature
The history of research into the electrical properties of plants
One of the characteristic features of living organisms is the ability to irritate.
Charles Darwin attached great importance to the irritability of plants. He studied in detail the biological characteristics of insectivorous representatives of the plant world, which are distinguished by high sensitivity, and presented the results of the research in the wonderful book "On Insectivorous Plants", published in 1875. In addition, various plant movements attracted the attention of the great naturalist. Taken together, all the studies suggested that the plant organism is remarkably similar to the animal.
The widespread use of electrophysiological methods has allowed animal physiologists to achieve significant progress in this area of knowledge. It was found that electric currents (biocurrents) constantly arise in the organisms of animals, the spread of which leads to motor reactions. C. Darwin suggested that similar electrical phenomena also take place in the leaves of insectivorous plants, which have a rather pronounced ability to move. However, he himself did not test this hypothesis. At his request, experiments with the Venus flytrap plant were carried out in 1874 by a physiologist at the University of OxfordBurdan Sanderson... Having connected a leaf of this plant to a galvanometer, the scientist noted that the arrow immediately deviated. This means that electrical impulses arise in the living leaf of this insectivorous plant. When the researcher irritated the leaves by touching the bristles located on their surface, the galvanometer needle deflected in the opposite direction, as in the experiment with the animal's muscle.
German physiologist Hermann Munch , who continued his experiments, in 1876 came to the conclusion that the leaves of the Venus flytrap are electromotorically similar to the nerves, muscles and electrical organs of some animals.
In Russia, electrophysiological methods were usedN.K. Levakovskyto study the phenomena of irritability in bashful mimosa. In 1867 he published a book entitled "On the movement of irritable plant organs." In the experiments of N.K. Levakovsky, the strongest electrical signals were observed in those specimens mimosa which responded most vigorously to external stimuli. If mimosa is quickly killed by heating, then the dead parts of the plant do not produce electrical signals. The author also observed the appearance of electrical impulses in stamensthistle and thistle, in the petioles of sundew leaves.It was subsequently found that
Bioelectric potentials in plant cells
Plant life is associated with moisture. Therefore, the electrical processes in them are most fully manifested in the normal mode of humidification and attenuate during wilting. This is due to the exchange of charges between the liquid and the walls of the capillary vessels during the flow of nutrient solutions through the capillaries of plants, as well as to the processes of ion exchange between cells and the environment. The most important for vital activity electric fields are excited in cells.
So, we know that ...
- Pollen carried by the wind is negatively charged‚Approaching in size to the charge of dust particles during dust storms. In the vicinity of plants losing pollen, the ratio between positive and negative light ions changes sharply, which favorably affects the further development of plants.
- In the practice of spraying pesticides in agriculture, it was found thatchemicals with a positive charge are deposited to a greater extent on beets and apple trees, and chemicals with a negative charge are deposited on lilacs.
- One-sided illumination of a leaf excites an electrical potential difference between its illuminated and unlit areas and the petiole, stem and root.This potential difference expresses the plant's response to changes in its body associated with the beginning or termination of the process of photosynthesis.
- Germination of seeds in a strong electric field(e.g. near the corona electrode)leads to changethe height and thickness of the stem and the density of the crown of developing plants. this occurs mainly due to the redistribution in the plant organism under the influence of the external electric field of the space charge.
- The damaged place in plant tissues is always charged negativelyrelatively intact areas, and the dying areas of plants acquire a negative charge in relation to areas growing under normal conditions.
- Charged seeds of cultivated plants have a relatively high electrical conductivity and therefore quickly lose their charge.Weed seeds are closer in their properties to dielectrics and can retain a charge for a long time. This is used to separate crop seeds from weeds on the conveyor.
- Significant potential differences in the plant organism cannot be excitedBecause plants do not have a specialized electrical organ. Therefore, there is no “tree of death” among plants, which could kill living beings with its electrical power.
Effect of atmospheric electricity on plants
One of the characteristic features of our planet is the presence of a constant electric field in the atmosphere. The person does not notice him. But the electrical state of the atmosphere is not indifferent to him and other living beings that inhabit our planet, including plants. Above the Earth at an altitude of 100-200 km, there is a layer of positively charged particles - the ionosphere.
This means that when you walk along a field, street, square, you move in an electric field, you inhale electric charges.
The influence of atmospheric electricity on plants has been studied since 1748 by many authors. This year Abbot Nolet reported on experiments in which he electrified plants by placing them under charged electrodes. He observed the acceleration of germination and growth. Grandieu (1879) observed that plants that were not exposed to atmospheric electricity, as they were placed in a wire mesh grounded box, showed a weight reduction of 30-50% compared to control plants.
Lemström (1902) exposed plants to the action of air ions, placing them under a wire equipped with points and connected to a high voltage source (1 m above ground level, ion current 10-11 - 10 -12 A / cm 2 ), and he found an increase in weight and length of more than 45% (e.g. carrots, peas, cabbage).
The fact that plant growth was accelerated in an atmosphere with an artificially increased concentration of positive and negative small ions was recently confirmed by Krueger and his collaborators. They found that oat seeds reacted to positive as well as negative ions (concentration of about 10 4 ions / cm 3 ) an increase of 60% in the total length and an increase in fresh and dry weight of 25-73%. Chemical analysis of the aerial parts of the plants revealed an increase in the content of protein, nitrogen and sugar. In the case of barley, had an even greater increase (by about 100%) in total elongation; the increase in fresh weight was not large, but there was a marked increase in dry weight, which was accompanied by corresponding increases in protein, nitrogen and sugar.
Experiments with plant seeds were also carried out by Warden. He found that the germination of green beans and green peas became earlier with increasing levels of ions of either polarity. The final percentage of germinated seeds was lower with negative ionization compared to the control group; germination in the positively ionized group and the control group was the same. As the seedlings grew, the control and positively ionized plants continued to grow, while the negatively ionized plants mostly wither and die.
Influence in recent years has been a strong change in the electrical state of the atmosphere; different regions of the Earth began to differ from each other in the ionized state of the air, which is due to its dustiness, gas content, etc. The electrical conductivity of air is a sensitive indicator of its purity: the more foreign particles in the air, the more ions settle on them and, therefore, the electrical conductivity of the air becomes less.
So, in Moscow in 1 cm 3
air contains 4 negative charges, in St. Petersburg - 9 such charges, in Kislovodsk, where the standard of air purity is 1.5 thousand particles, and in the south of Kuzbass in the mixed forests of the foothills, the number of these particles reaches 6 thousand. This means that where there are more negative particles, it is easier to breathe, and where there is dust, a person gets less of them, since dust particles settle on them.
It is well known that near fast flowing water the air refreshes and invigorates. It contains a lot of negative ions. Back in the 19th century, it was determined that larger drops in splashes of water are positively charged, and smaller drops are negatively charged. As large droplets settle faster, negatively charged small droplets remain in the air.
On the contrary, the air in confined spaces with an abundance of all kinds of electromagnetic devices is saturated with positive ions. Even a relatively short stay in such a room leads to lethargy, drowsiness, dizziness and headaches.
Research methodology
Study of damage currents in various plants.
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LITERATURE
- Bogdanov K. Yu. Physicist visiting a biologist. - Moscow: Nauka, 1986.144 p.
- Vorotnikov A.A. Physics for the young. - M: Harvest, 1995-121s.
- Katz Ts.B. Biophysics in physics lessons. - M: Education, 1971-158s.
- Perelman Ya.I. Entertaining physics. - M: Science, 1976-432s.
- Artamonov V.I. Entertaining plant physiology. - M .: Agropromizdat, 1991.
- Arabadzhi V.I., The Riddles of Plain Water.- M .: "Knowledge", 1973.
- http://www.pereplet.ru/obrazovanie/stsoros/163.html
- http://www.npl-rez.ru/litra/bios.htm
- http://www.ionization.ru
Electric field of the Earth
Measurements with an electrometer show that an electric field exists at the surface of the Earth, even if there are no charged bodies nearby. This means that our planet has a certain electric charge, that is, it is a charged ball of large radius.
The study of the Earth's electric field showed that, on average, the modulus of its intensity E= 130 V / m, and the lines of force are vertical and directed to the Earth. The strength of the electric field has the greatest value in the middle latitudes, and towards the poles and the equator it decreases. Therefore, our planet as a whole has negative charge, which is estimated as q= –3 ∙ 10 5 C, and the atmosphere as a whole is positively charged.
Electrification of thunderclouds is carried out by the combined action of various mechanisms. First, the crushing of raindrops by air currents. As a result of fragmentation, falling larger drops are charged positively, while smaller ones remaining in the upper part of the cloud are charged negatively. Secondly, electric charges are separated by the electric field of the Earth, which has a negative charge. Third, electrification occurs as a result of the selective accumulation of ions by droplets of different sizes in the atmosphere. The main mechanism is the fall of large enough particles, electrified by friction against atmospheric air.
Atmospheric electricity in a given area depends on global and local factors. Areas where the effect of global factors prevails are considered as zones of "good" or undisturbed weather, and where the effect of local factors prevails - as zones of disturbed weather (areas of thunderstorms, precipitation, dust storms, etc.).
Measurements show that the potential difference between the Earth's surface and the upper edge of the atmosphere is approximately 400 kV.
Where do the field lines of force begin and end on Earth? In other words, where are those positive charges that compensate for the negative charge of the Earth?
Studies of the atmosphere have shown that at an altitude of several tens of kilometers above the Earth there is a layer of positively charged (ionized) molecules called ionosphere... It is the charge of the ionosphere that compensates for the charge of the Earth, i.e., in fact, the lines of force of the Earth's electricity go from the ionosphere to the surface of the Earth, as in a spherical capacitor, the plates of which are concentric spheres.
Under the influence of an electric field in the atmosphere, a conduction current flows to the Earth. Through each square meter of the atmosphere perpendicular to the earth's surface, on average, a current flows I~ 10-12 A ( j~ 10 –12 A / m 2). The entire surface of the Earth has a current of approximately 1.8 kA. With such a current strength, the negative charge of the Earth should have disappeared within a few minutes, but this does not happen. Due to the processes taking place in the Earth's atmosphere and outside it, the Earth's charge remains unchanged on average. Consequently, there is a mechanism of continuous electrification of our planet, leading to the appearance of a negative charge in it. What are such atmospheric “generators” that charge the Earth? These are rains, blizzards, sandstorms, tornadoes, volcanic eruptions, splashing water by waterfalls and surf, steam and smoke from industrial facilities, etc. But the greatest contribution to the electrification of the atmosphere is made by clouds and precipitation. As a rule, clouds in the upper part are positively charged, and in the lower part they are negatively charged.
Careful research has shown that the current in the Earth's atmosphere is maximum at 19:00 and minimum at 4:00 GMT.
Lightning
For a long time it was believed that about 1800 thunderstorms simultaneously occurring on the Earth give a current of ~ 2 kA, which compensates for the loss of the negative charge of the Earth due to conduction currents in zones of "good" weather. However, it turned out that the current of thunderstorms is much less than the indicated one and it is necessary to take into account the processes of convection over the entire surface of the Earth.
In areas where the field strength and density of space charges are the highest, lightning can arise. The discharge is preceded by the appearance of a significant difference in electrical potential between the cloud and the Earth or between neighboring clouds. The resulting potential difference can reach a billion volts, and the subsequent discharge of accumulated electrical energy through the atmosphere can create short-term currents from 3 kA to 200 kA.
There are two classes of linear lightning: ground-based (striking the Earth) and intra-cloud. The average length of lightning discharges is usually several kilometers, but sometimes intra-cloud lightning reaches 50-150 km.
The development process of ground lightning consists of several stages. At the first stage, in the zone where the electric field reaches a critical value, impact ionization begins, created by free electrons, which are present in small quantities. Under the influence of an electric field, electrons acquire significant speeds towards the Earth and, colliding with the molecules that make up the air, ionize them. Thus, electron avalanches appear, which turn into filaments of electrical discharges - streamers, which are well-conducting channels, which, merging, give rise to a bright thermally ionized channel with high conductivity - step lightning leader... As the leader moves towards the Earth, the field strength at its end increases and under its action, a response streamer is thrown out of objects protruding on the Earth's surface, connecting with the leader. If you do not allow the streamer to appear (Fig. 126), then a lightning strike will be prevented. This zipper feature is used to create lightning rod(fig. 127).
Multichannel lightning is common. They can count up to 40 discharges at intervals from 500 μs to 0.5 s, and the total duration of a multiple discharge can be up to 1 s. It usually penetrates deep into the cloud, forming many branched channels (Fig. 128).
Rice. 128. Multichannel Lightning
Most often, lightning occurs in cumulonimbus clouds, then they are called thunderstorms; sometimes lightning is formed in stratus clouds, as well as during volcanic eruptions, tornadoes and dust storms.
Lightning is more likely to strike again at the same point, unless the object is destroyed by the previous strike.
Lightning strikes are accompanied by visible electromagnetic radiation. With an increase in the current in the lightning channel, the temperature rises to 10 4 K. A change in pressure in the lightning channel with a change in the current and the termination of the discharge causes sound phenomena called thunder.
Thunderstorms with lightning occur almost throughout the planet, with the exception of its poles and arid regions.
Thus, the "Earth - atmosphere" system can be considered a continuously operating electrophoretic machine that electrifies the surface of the planet and the ionosphere.
Lightning has long been a symbol of "heavenly power" for man and a source of danger. With the elucidation of the nature of electricity, man learned to protect himself from this dangerous atmospheric phenomenon with the help of a lightning rod.
The first lightning rod in Russia was erected in 1856 over the Peter and Paul Cathedral in St. Petersburg after lightning struck the spire twice and set the cathedral on fire.
You and I live in a constant electric field of considerable intensity (Fig. 129). And, it would seem, there should be a potential difference of ~ 200 V between the crown and heels of a person. Why does the electric current not pass through the body? This is due to the fact that the human body is a good conductor, and as a result of this, some charge from the surface of the Earth is transferred to it. As a result, the field around each of us changes (Fig. 130) and our potential becomes equal to the potential of the Earth.
Literature
Zhilko, V.V. Physics: textbook. allowance for the 11th grade. general education. institutions with rus. lang. training with a 12-year training period (basic and advanced) / V.V. Zhilko, L.G. Markovich. - Minsk: Nar. Asveta, 2008 .-- S. 142-145.
