Electricity is a natural phenomenon. Electricity is a property that produces repulsion and attraction between subatomic particles such as electrons and protons. It is one of the four basic interactions in nature. There are two kinds of electricity or charges: we call one positive and the other negative. Through experiments, we found that charged objects repel each other when the polarity is the same, attract each other when the polarity is opposite, and the attraction or repulsion obeys Coulomb's law.

The discharge phenomenon in nature The unit of charge in the International System of Units is Coulomb.

Ancient discovery

In China, the ancients believed that the phenomenon of electricity was generated by the excitation of Yin and Yang, and Shuo Wen Jie Zi said that "electricity, Yin and Yang excite brilliance, from rain to spirit". "Vocabulary" includes "thunder from behind, electricity from application. Yin and yang become thin and become thunder, and discharge becomes electricity. " There is a record about static electricity in Lun Heng (about the first century AD, that is, the Eastern Han Dynasty). When amber or tortoise shell is rubbed, it can attract light and small objects, and it also describes the phenomenon that silk is rubbed to generate electricity. However, ancient China didn't know much about electricity.

Around 600 BC, the Greek philosopher Thales (640-546 BC) knew that the friction of amber would attract fluff or sawdust, which is called static electricity. Electricity in English means "amber" in ancient Greek. Static electricity in Greek is (elektron)

Modern exploration

/kloc-in the 0/8th century, the west began to explore various phenomena of electricity. American scientist Benjamin Franklin (1706 ~ 1790) thinks that electricity is a weightless fluid and exists in all objects. When an object gets more electricity than normal, it is called positively charged; If it is less than a positive constant, it is called negatively charged. The so-called "discharge" is the process from positive current to negative current. This theory is not completely correct, but it retains the names of positive charge and negative charge. The concept of "electricity" in this period is a material proposition.

Franklin did many experiments and put forward the concept of current for the first time. 1752, in a kite experiment, he put a kite with a key in the cloud with a metal wire, and the metal wire wet by rain led lightning in the air between his finger and the key, which proved that lightning in the air and electricity on the ground are the same thing.

From matter to electric field

Electricity began to develop in18th century. J.B.Priestley (1767) and Coulomb (C.A. Coulomb1736-1806) found that the force between electrostatic charges is inversely proportional to the distance, which laid the foundation for static electricity.

/kloc-in 0/800, Italian Volt (A.Voult) made the first battery by immersing copper and tin in salt water and connecting wires. It provided the first continuous power supply and was called the ancestor of modern batteries. 183 1 year, M. Faraday of Britain demonstrated the generation of induced current by using the change of magnetic field effect. In 185 1, he put forward the concept of physical power line. This is the first time to emphasize the concept of charge transfer to electric field.

Electric and magnetic fields

1865, Maxwell put forward the mathematical formula of electromagnetic field theory and provided the concept of displacement current. The change of magnetic field can produce electric field, and the change of electric field can produce magnetic field. Maxwell predicted the existence of electromagnetic radiation, and such electromagnetic waves were shown in H.Hertz of 1887. As a result, Maxwell integrated electricity and magnetism into a theory, which also proved that light is an electromagnetic wave.

The development of Maxwell's electromagnetic theory also explains microscopic phenomena, pointing out the existence of split charges rather than continuity. 1895, H.A. Lorenz assumed that these split charges were electrons, and the role of electrons was determined by the electromagnetic field of Maxwell's electromagnetic equation. 1897, J.J.Thomson of Britain confirmed that the electronicity of these electrons is negatively charged. 1898, W.Wien observed the deflection of anode rays and found the existence of positively charged particles.

From particle to quantum

Humans have always described the world of "electricity" with particles and waves existing in nature. /kloc-in the 0/9th century, the appearance of quantum theory put the originally constructed particle world to the test again. Werner Heisenberg's "uncertainty principle" holds that the velocity and position of a particle cannot be measured at the same time; Electrons are no longer countable particles; Nor does it run in a fixed orbit.

1923, Louis Blay proposed that tiny particles have both particle property and fluctuation when they move, which is called "mass-wave duality", while Erwin Schrodinger used mathematical methods to describe the behavior of electrons with functions, and obtained the probability distribution of electrons in space with wave mechanics model. According to Heisenberg's uncertainty principle, we can't measure accurately. In niels bohr's hydrogen atom model, the electron movement radius of the ground state atom is the position with the largest probability of electron occurrence in the wave mechanics model.

With the development of science, people gradually understand that the values obtained by the physical quantity of electricity are discontinuous and the laws they reflect are statistical.

2. What are the basic common sense of safe electricity use?

1. It is forbidden to move running household appliances by hand, such as desk fans, washing machines, televisions, etc.

2. It is forbidden to repair live lines or equipment at home by hand.

3. It is forbidden to touch with wet hands and wipe lamps, switches and other electrical appliances with wet cloth.

4. It is forbidden to change the three-eye plug into two-eye plug at will.

5. It is forbidden to pull and connect wires indiscriminately.

6. Without permission, it is forbidden to install electrical appliances on the original line.

7. Unqualified electrical equipment is strictly prohibited.

8. It is forbidden to use electric irons, hair dryers, electric stoves and other electrical appliances without supervision.

9. Fishing, theft prevention and hunting in private power grids are prohibited.

10. It is forbidden to use lead wire and copper wire instead of fuse as fuse. Wait a minute.

3. All common sense of electricity use, short.

1, electric shock accident: (1) Definition: The injury caused by a certain intensity of current passing through human body belongs to electric shock accident.

(2) Danger: It is related to factors such as current size and power-on time. 2. safe voltage: The voltage is not higher than 36V.

The power circuit voltage of 380V and the household circuit voltage of 220V both exceed that of safe voltage. 3. Electric shock form of low-voltage circuit: single-line electric shock: people standing on the ground come into contact with the fire line; Double-wire electric shock: people come into contact with live wire and neutral wire at the same time.

The human body is a conductor. When the human body becomes a part of a closed circuit, current will flow. If the current reaches a certain level, an electric shock accident will occur.

If one hand touches the live line and the other hand touches the zero line, the human body and the wire form a closed circuit, and current flows through the human body, causing an electric shock accident. If one hand touches the live line and the other hand stands on the ground without touching the zero line, the conductor, human body and the earth will also form a closed circuit, and current will also flow through the human body, thus causing an electric shock accident.

4. It is easy to get an electric shock: (1) The insulation of wires connected with electrical appliances and sockets is damaged; (2) The electrical enclosure is not grounded; (3) drying clothes on the steel wire; (4) The outdoor antenna of the TV set is in contact with the wire; 5. Electric shock accident of court circuit (belonging to low-voltage electric shock): It is caused by direct or indirect contact of human body with live wires, and it forms a path with ground wire or zero wire. Therefore, it is necessary to distinguish between zero line and ground line. Although there is no voltage between the ground wire and the zero wire under normal circumstances, the ground wire and the zero wire must not be connected, otherwise it will easily lead to an electric shock accident.

6 voltage electric shock accidents: divided into high voltage arc electric shock and step voltage electric shock. 7. Principle of full power utilization: Do not touch low-voltage charged bodies, and do not approach high-voltage charged bodies.

8. Electric first aid: The current passing through the human body may stop the heartbeat and breathing, and the heat generated by the current will also burn the limbs. If someone gets an electric shock, never pull the electrocuted person directly. In this way, the person who saves lives will also become part of the closed circuit and get an electric shock.

The power supply should be cut off immediately, and the wire should be connected with insulation such as a dry stick, so as to save the electric shock. If the person who gets an electric shock stops breathing, artificial respiration should be given to the person who gets an electric shock as soon as possible, and medical personnel should rescue him.

4. What is the knowledge about safe use of electricity?

1, not close to high-voltage charged bodies (outdoor high-voltage lines, beside transformers) and not touching low-voltage charged bodies.

2. Insert or unplug the plug without wet manual switch.

3, installation and maintenance of electrical appliances should wear insulating shoes, standing on the insulator, and cut off the power supply.

4, it is forbidden to use copper wire instead of fuse, it is forbidden to use rubber rubber instead of electrical insulation tape.

5, install electric shock protector in the circuit, and regularly check its sensitivity.

6. In thunderstorm weather, don't use the radio, video recorder and TV set, unplug the power plug and antenna plug of the TV set. Don't use the phone for the time being If you must use it, you can use the hands-free function.

7. It is forbidden to connect wires privately, and students are forbidden to use electric stoves, "quick heating" and other electrical appliances in the dormitory.

8. Don't fly kites and play ball under cables and wires.

Extended data:

Precautions:

1, people's safe voltage is not higher than 36 volts.

2. Do not touch the metal part of the pen tip when using the electric pen.

3. High-power electrical appliances must be grounded.

4. You can't connect the live wire and the ground wire with your body.

5. The total power of the electrical appliances used should not be too high, otherwise the excessive current will cause a fire.

6. Someone gets an electric shock, so you can't pull him with your body. Turn off the main switch immediately, and then separate the person from the wire with a dry stick.

Baidu encyclopedia-safe use of electricity

5. What is the common sense of safe electricity use in life?

1, the power cord and electrical equipment must be well insulated, and the live parts such as lamp holders, sockets and switches shall not be exposed to prevent electric shock.

2, don't pull the wire, to prevent electric shock or fire.

3, don't stand on the wet ground to move charged objects or try to clean charged household appliances with a wet rag to prevent electric shock.

4, fuse selection should be reasonable, avoid using copper wire, aluminum wire or iron wire instead, in case of fire.

5, the use of household appliances such as refrigerators, freezers, washing machines, etc. , should be equipped with grounding wire socket according to the requirements of product use.

6. When repairing or replacing the lamp holder, even if the switch is turned off, do not touch it directly by hand to prevent electric shock.

6. Basic knowledge of electricity

L, how did the electricity come from? A: This is a kind of energy. It is not produced out of thin air, but is transformed from water, heat, mechanical energy, atomic energy and other energy.

2. What is current? Answer: the water flowing in the water pipe is called water flow, and the electricity flowing in the wire is called current. That is to say, electric energy flows regularly in a certain direction along the object that transmits electricity, and it is invisible and intangible. The current speed is 300 thousand kilometers per second.

3. What is voltage? A: Voltage is also called potential difference, which means the same as water level difference. The height difference of water surface is called water level difference or water pressure. The greater the water level difference, the faster, farther and faster the water flow. The potential difference is called potential or voltage. The higher the voltage, the farther the current travels.

4. What is command? A: An object through which current can pass, that is, something that can conduct electricity, is called a conductor. All kinds of metals are conductors. Some liquids can conduct electricity like daily water, objects containing water can also conduct electricity, human bodies can also conduct electricity, the earth can also conduct electricity, and all kinds of animals and plants can conduct electricity. All these are conductors.

5. What is an insulator? A: Anything that is not easy to conduct electricity is called an insulator. Such as plastic, rubber, ceramics, glass, bakelite, dry air and wood, dry cotton cloth, etc. , do not transmit electricity, are insulators.

6. Why does the human body get an electric shock? Answer: If a person stands on the ground and his body touches something charged, his body can conduct electricity, and the ground can also conduct electricity. The current will be conducted to the ground through his body and he will get an electric shock.

7. Why does electric shock electrocute people? A: The longer the electric shock lasts, the more serious the consequences will be. The higher the voltage, the more dangerous it is; The greater the current, the greater the harm to people. Severe electric shock will affect people's central nervous system and heart, inhibit people's breathing or interrupt blood circulation, and people will die.

8. What if there is an electrical fire? Answer: When you smell burning rubber or burning plastic, check the wires quickly. If you find that the wire is burnt out, open the brake box immediately. When an electrical fire occurs, the power supply should be cut off first to put out the fire. Before cutting off the power supply, you can't put out the fire with water, because water is conductive. You should cover the fire with mud or sand. After the switch is turned on, the fire can be put out in any way, and there will be no electric shock accident due to fire fighting.

9. How to pay attention to electricity safety in daily life? Answer: in daily life, first of all, don't pull it privately. Unauthorized connection is a violation of the electricity system, the installation does not meet the requirements, and accidents are prone to occur; In addition, when replacing and wiping the light bulb in daily life, turn off the current first, don't wipe the light bulb with wet hands or wet cloth, stand on a wooden bench or table, and don't wipe it on the ground to prevent the switch from failing and leaking electricity; The metal part of the screw bulb is connected with the ground wire. When the light is on, the lamp holder has electricity, which is unsafe. The exposed screw part will get an electric shock when people touch it, so pay special attention.

With the continuous improvement of people's living standards, the connection between electricity and family life is getting closer and closer. If it is not used properly, all kinds of electricity accidents will occur, causing great losses to people's lives and property. Therefore, in household electricity, we need to pay attention to ten taboos:

(1) The fuse selection of household watt-hour meter should be reasonable, and copper wire, aluminum wire or iron wire should not be used instead.

(2) The power plugs of household appliances such as desk fans, floor fans, washing machines and refrigerators should use three-eye plugs with grounding protection wires, and avoid using two-eye plugs.

(3) Replace or clean bulbs and tubes, and do not use wet hands or wet cloth.

(4) If the wire is damaged, it should not be wrapped with wet paste.

(5) When repairing electrical appliances, cut off the power supply to avoid live working.

(6) When repairing or replacing the lamp holder, don't touch it with your hands even if the switch is turned off.

(7) When using electrical equipment, plug in the power plug first, and then close the switch; After use, turn off the switch first, and then pull out the bolt to avoid improper operation.

8) The electric lamp should be fixed in place and installed, and it is forbidden to connect the lamp holder wire too long to be used as a traveling lamp.

(9) When an electrical fire occurs, first cut off the power supply to put out the fire, and don't put it out directly with water.

10) If anyone is found to get an electric shock, the power supply of the electrocuted person must be quickly disconnected, and it is forbidden to directly pull the electrocuted person away by hand.

I hope it will help everyone.

7. List the common sense of safe electricity use in life.

(a) the safety of household electricity.

1. Don't overload electricity. If the power load exceeds the specified capacity, it shall apply to the power supply department for capacity increase. Large-capacity electrical equipment such as air conditioners and ovens should use dedicated lines.

2. Choose qualified electrical appliances, and don't buy and use fake and inferior electrical appliances, wires, trunking (pipes), switches, plugs and sockets.

3. Don't lay wires and connect electrical equipment without permission or ask unqualified decoration teams and personnel. Find qualified units and personnel to install and repair electrical appliances.

4. Do a good job of grounding protection for the metal shell of electrical appliances requiring grounding, and don't forget to install grounding wire for the three-eye socket and socket box; Don't change the three-eye plug into two-eye plug at will.

5. We should choose the fuse suitable for wire load, and don't arbitrarily thicken the fuse. It is forbidden to use copper wire, iron wire and aluminum wire instead of fuse.

6. Don't wipe the charged lamp holder, switch and socket with wet hands and wet cloth.

7. The leakage protection switch should be installed in a place free of corrosive gas and explosive dangerous goods, and the sensitivity test of the leakage protection switch should be carried out regularly.

8. The clothes hanger should keep a safe distance from the power cord, and do not put the clothes drying rod on the power cord.

9. Install the TV outdoor antenna firmly and reliably, not higher than the nearby lightning rod or close to the high-voltage line.

10. It is strictly forbidden to set up power grids without permission, and to guard against theft, hunt, catch rats and fish with electricity.

(B) How to prevent common power accidents

1. Don't pull the wires.

2. When replacing fuses, disassembling and repairing electrical appliances or moving electrical equipment, the power supply must be cut off, and do not risk live working.

5. When using electric iron, hair dryer, electric stove and other household heaters, people should not leave.

4. When the electrical equipment is found to smoke or smell, the power supply should be quickly cut off for inspection.

5. clothes can't be baked on electric heating equipment.

6. Take care of power facilities and don't fly kites near overhead wires and distribution transformers.

(3) How to deal with electric shock accidents in an emergency.

The harm of electric current to human body is mainly burns and strong muscle spasms caused by electric heating, which will affect the respiratory center and heart, cause respiratory depression or cardiac arrest, and severe electric injury will cause disability and even directly endanger life.

1. To get an electric shock quickly out of the power supply, immediately pull down the power switch or unplug the power supply. If you can't find or disconnect the power supply in time, connect the wires with insulators such as dry bamboo poles and wooden sticks.

2. Move the electric shock victim who is out of power supply to a ventilated and dry place to lie on his back, relax his coat and belt, observe whether the electric shock victim breathes or not, and touch the carotid artery for pulsation.

3. Give first aid. If the person who gets an electric shock stops breathing and heartbeat, he should perform cardiopulmonary resuscitation while giving artificial respiration, and call an ambulance in time.

4. Get to the hospital as soon as possible and continue the rescue on the way.

8. What is the knowledge of electricity use?

L, know the master switch, learn to turn off the master switch in an emergency.

2. Don't touch and test the inside of the power socket with your hands or conductive objects (such as wire, nails, pins and other metal products).

3. Don't touch the appliance with wet hands or wipe it with wet cloth.

4, electrical appliances should be unplugged after use; Do not pull the wire forcibly when plugging and unplugging the power plug to prevent the insulation layer of the wire from being damaged and causing electric shock; The insulation layer of the wire is peeling off, so it is necessary to replace the wire in time or wrap it with insulating tape.

5, found someone get an electric shock to try to turn off the power in time; Or use dry wooden sticks and other things to separate the electric shock victim from the charged electrical appliances, and don't save people directly by hand; Younger students should ask adults for help in this situation, and don't handle it by themselves to prevent electric shock.

6. Don't remove or install the power cord, socket and plug at will. Even if it is as simple as installing a light bulb, it should be turned off first and carried out under the guidance of parents.

9. What common sense do you know about safe use of electricity?

1. Apply for electricity, find a power supply station for installation and maintenance, and don't pull the wires without permission.

It is everyone's responsibility to use electricity safely. Consciously abide by the rules and regulations for safe use of electricity. Low-voltage lines should be equipped with leakage protectors, and fuses (fuses), fuses (fuses) or fuse tubes should be selected reasonably. It is forbidden to use copper, aluminum and iron wire instead. 3. Don't build houses, pile firewood, drill fields, drill wells and plant trees under wires, and don't perform or show movies near live equipment such as wires to prevent electric shock and fire. 4. Measures should be taken when erecting a derrick, repairing a house or cutting down trees near the power line. For the line equipment that may be encountered, you need to find a power supply station after the power failure. 5, the carriage through the power line, don't whip, motor vehicles driving or working in the field, don't touch the pole and stay. 6, are not allowed to be near the wire quarrying blasting, are not allowed to dig a hole or soil near the pole, are not allowed to dig a fish pond near the pole, are not allowed to be tied to animals on the pole, are not allowed to destroy the guy, in case the pole is broken. 7. Power lines, communication lines and broadcasting lines should be clearly separated. When the wire is connected with other wires, you should immediately find a power supply office to deal with it. 8. Keep enough distance between the iron wire and the electric wire for drying clothes. Don't entangle them, and don't hang clothes on the electric wire. 9. Educate children not to play with electrical equipment, climb poles, climb transformer platforms, shake cables, fly kites and shoot birds near wires, and don't throw things at wires, magnetic bottles and transformers. 10, don't go near the broken wire, send someone to watch it, and find a power supply station to deal with it quickly. Temporary electrical equipment, such as 1 1, small pumps, threshers, etc., are not allowed to move with electricity, are not allowed to connect electricity with hooks, are not allowed to use stored stranded wires, and are not allowed to use ground climbing lines and waist lines. It is strictly forbidden for minors to approach live equipment, and it is strictly forbidden for those who have not passed the examination by the electric power department to operate electrical equipment. 12, don't touch household appliances such as lamp holders, switches and plugs with your hands. If there is any damage or aging leakage, please find a power supply station to repair or replace it. The metal shell of household electrical equipment should be properly grounded. 13, do not use unqualified lamp holders, light wires, switches, sockets and other electrical equipment. Electrical equipment should be kept clean and intact, and the light wire should not be too long or pulled randomly. 14, when the radio horn calls or smokes, turn off the switch, and don't use water to put out the fire. 15. If the branch is found to touch the conductor, it should be handled by the power supply immediately. 16, it is forbidden to set up a special power grid for theft prevention, fishing, hunting, rat catching and insect prevention. It is forbidden to use "one line and one place" lighting. 17, non-power supply personnel are not allowed to operate the high-voltage switch, and are not allowed to enter the distribution room to touch electrical equipment. 18. If you find an electric shock, don't pull the electrocuted person by hand. Pull down the switch, open the wire with a dry wooden stick and a dry bamboo pole, and immediately carry out on-site first aid with correct artificial respiration or chest compressions.

I hope I can help you!