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In real life, the mechanism of electricity gives many well-known effects, such as lightning, triboelectricity, electrostatic induction, electromagnetic induction, and so on.<\/p>\n\n\n\n
Several concepts about electricity<\/h2>\n\n\n\n![\"\"](\"https:\/\/blog.seeedstudio.com\/wp-content\/uploads\/2020\/09\/\u539f\u5b50.png\")
Ref: atom<\/a><\/figcaption><\/figure><\/div>\n\n\n\nElectron:<\/strong> In an atom, the negatively charged surrounding the nucleus is\ncalled an electron.<\/p>\n\n\n\nElectric\ncharge:<\/strong> It is the amount of electronic load, the\nsource of electric field. When a positive charge undergoes a net movement, it\nconstitutes a current in the direction of its movement.<\/p>\n\n\n\nElectric\nfield: <\/strong>The area around the positive or negative\ncharge that generates electricity. The direction of the electric field changes\nfrom high potential to low potential.<\/p>\n\n\n\nVoltage:\n<\/strong>It is a kind of potential energy that tends to make\nelectrons flow through the wire. If you must work on the electric field to move\nthe charge from one point to another, it is said that there is a voltage\n(potential difference) between the two points.<\/p>\n\n\n\nElectric current: <\/strong>The directional movement of electric charge forms an electric current, usually measured in ampere (Ampere). Any charged particle in motion can form an electric current.<\/p>\n\n\n\nThe origin of electricity<\/h2>\n\n\n\n
In\n1767:<\/strong> Joseph Priestley did an experiment and found\nthat in the inside of a charged metal container, the electric force is zero.\nFrom the results of this experiment, he accurately guessed that the attraction\nand gravitation of charged objects acting on each other obey the same law. In\n1785, Charles Coulomb used a torsion balance to test Priestley\u2019s conjecture\nthat the force exerted by two charged objects on each other is inversely\nproportional to the square of the distance. He laid down the basic law of\nstatic electricity, namely Coulomb’s law<\/strong>.\nAt this point, the study of electricity has become a kind of precision science.<\/p>\n\n\n\nIn\n1820:<\/strong> Hans Oster unexpectedly discovered during an\nexperiment in class that the current can deflect the direction of the compass,\ndemonstrating that a magnetic field is generated around the current, which is\nthe Galvanomagnetic effect<\/strong>.<\/p>\n\n\n\nIn\n1820<\/strong>\uff1a<\/strong> Andre Marie\nAmpere gave a quantitative description of the Galvanomagnetic effect and gave\nthe Ampere\u2019s law<\/strong> and Ampere\u2019s law<\/strong>. The research results of\nthe two of them successfully connected the electric and magnetic phenomena\ntogether, collectively called the “electromagnetic phenomenon.”<\/p>\n\n\n\nIn\n1831: <\/strong>Michael Faraday and Joseph Henry\nindependently discovered electromagnetic induction-changes in magnetic fields\ncan generate electric fields.<\/p>\n\n\n\nIn\n1865: <\/strong>James Maxwell integrated electromagnetism,\nproposed Maxwell’s equations<\/strong>, and\ndeduced the electromagnetic wave equation.<\/p>\n\n\n\nIn the nineteenth and twentieth centuries,\nelectricity developed vigorously. So far, the theoretical system of\nelectromagnetics tends to be perfected.<\/p>\n\n\n\n
In\n1859:<\/strong> The German physicist Julius Pl\u00fcck applied a\nhigh voltage between the electrodes at both ends of the vacuum tube to make a\ncathode ray.<\/p>\n\n\n\nIn\n1897: <\/strong>Joseph Thomson did experiments to prove that\nthe cathode rays are composed of negatively charged particles called electrons,\nso he discovered electrons.<\/p>\n\n\n\nIn 1905: <\/strong>Albert Einstein published a paper explaining many experimental data of the photoelectric effect. Einstein argued that the light beam is composed of a group of discrete quanta (now called photons), rather than continuous fluctuations. If the frequency of the photon is greater than a certain limit frequency, the photon has enough energy to make the electrons on the metal surface escape, causing the photoelectric effect.<\/p>\n\n\n\nAlternating current(AC)<\/h2>\n\n\n\n
Alternating current refers to the current whose current direction changes periodically with time, and the average current in one cycle is zero. Unlike direct current, its direction changes over time, while direct current does not change periodically. Usually alternating current (AC for short) has a sinusoidal waveform. Alternating current can effectively transmit power. But in fact, there are other waveforms, such as triangular waves and square waves. The mains electricity used in daily life is an alternating current with a sinusoidal waveform.<\/p>\n\n\n\n
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Ref: AC<\/a><\/figcaption><\/figure><\/div>\n\n\n\nDirect current (DC)<\/h2>\n\n\n\n
Direct current is an electric charge,\nusually electrons, flowing in one direction. The current density changes with\ntime, but the direction of movement is usually the same at all times. As an\nadjective, DC can be used as a reference voltage (its polarity will never\nchange).<\/p>\n\n\n\n
In a DC circuit, electrons are formed from\nthe cathode, negative electrode, and negative magnetic pole, and move to the\nanode, positive electrode, and positive magnetic pole. <\/p>\n\n\n\n
Direct current can be generated by\nelectrochemistry, photovoltaic cells or battery packs, or by rectification of\nalternating current. Alternating current can be converted to direct current\nthrough a power supply consisting of a converter, a rectifier (to prevent the\ncurrent from flowing in the opposite direction), and a filter (to eliminate the\njitter in the current flowing out of the rectifier).<\/p>\n\n\n\n
Virtually all electronic and computer hardware require direct current to work. The demand for current ranges from close to zero in electronic watches to over 100 amperes required by wireless communication energy amplifiers. Devices that use vacuum tubes, such as high-energy radio or television broadcast transmitters or cathode ray tube (CRT) displays, require about 150 volts to several thousand volts of direct current.<\/p>\n\n\n\n
![\"\"](\"https:\/\/blog.seeedstudio.com\/wp-content\/uploads\/2020\/09\/\u76f4\u6d41\u7535.png\")
Ref: DC<\/a><\/figcaption><\/figure><\/div>\n\n\n\n
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Electron:<\/strong> In an atom, the negatively charged surrounding the nucleus is\ncalled an electron.<\/p>\n\n\n\n Electric\ncharge:<\/strong> It is the amount of electronic load, the\nsource of electric field. When a positive charge undergoes a net movement, it\nconstitutes a current in the direction of its movement.<\/p>\n\n\n\n Electric\nfield: <\/strong>The area around the positive or negative\ncharge that generates electricity. The direction of the electric field changes\nfrom high potential to low potential.<\/p>\n\n\n\n Voltage:\n<\/strong>It is a kind of potential energy that tends to make\nelectrons flow through the wire. If you must work on the electric field to move\nthe charge from one point to another, it is said that there is a voltage\n(potential difference) between the two points.<\/p>\n\n\n\n Electric current: <\/strong>The directional movement of electric charge forms an electric current, usually measured in ampere (Ampere). Any charged particle in motion can form an electric current.<\/p>\n\n\n\n In\n1767:<\/strong> Joseph Priestley did an experiment and found\nthat in the inside of a charged metal container, the electric force is zero.\nFrom the results of this experiment, he accurately guessed that the attraction\nand gravitation of charged objects acting on each other obey the same law. In\n1785, Charles Coulomb used a torsion balance to test Priestley\u2019s conjecture\nthat the force exerted by two charged objects on each other is inversely\nproportional to the square of the distance. He laid down the basic law of\nstatic electricity, namely Coulomb’s law<\/strong>.\nAt this point, the study of electricity has become a kind of precision science.<\/p>\n\n\n\n In\n1820:<\/strong> Hans Oster unexpectedly discovered during an\nexperiment in class that the current can deflect the direction of the compass,\ndemonstrating that a magnetic field is generated around the current, which is\nthe Galvanomagnetic effect<\/strong>.<\/p>\n\n\n\n In\n1820<\/strong>\uff1a<\/strong> Andre Marie\nAmpere gave a quantitative description of the Galvanomagnetic effect and gave\nthe Ampere\u2019s law<\/strong> and Ampere\u2019s law<\/strong>. The research results of\nthe two of them successfully connected the electric and magnetic phenomena\ntogether, collectively called the “electromagnetic phenomenon.”<\/p>\n\n\n\n In\n1831: <\/strong>Michael Faraday and Joseph Henry\nindependently discovered electromagnetic induction-changes in magnetic fields\ncan generate electric fields.<\/p>\n\n\n\n In\n1865: <\/strong>James Maxwell integrated electromagnetism,\nproposed Maxwell’s equations<\/strong>, and\ndeduced the electromagnetic wave equation.<\/p>\n\n\n\n In the nineteenth and twentieth centuries,\nelectricity developed vigorously. So far, the theoretical system of\nelectromagnetics tends to be perfected.<\/p>\n\n\n\n In\n1859:<\/strong> The German physicist Julius Pl\u00fcck applied a\nhigh voltage between the electrodes at both ends of the vacuum tube to make a\ncathode ray.<\/p>\n\n\n\n In\n1897: <\/strong>Joseph Thomson did experiments to prove that\nthe cathode rays are composed of negatively charged particles called electrons,\nso he discovered electrons.<\/p>\n\n\n\n In 1905: <\/strong>Albert Einstein published a paper explaining many experimental data of the photoelectric effect. Einstein argued that the light beam is composed of a group of discrete quanta (now called photons), rather than continuous fluctuations. If the frequency of the photon is greater than a certain limit frequency, the photon has enough energy to make the electrons on the metal surface escape, causing the photoelectric effect.<\/p>\n\n\n\n Alternating current refers to the current whose current direction changes periodically with time, and the average current in one cycle is zero. Unlike direct current, its direction changes over time, while direct current does not change periodically. Usually alternating current (AC for short) has a sinusoidal waveform. Alternating current can effectively transmit power. But in fact, there are other waveforms, such as triangular waves and square waves. The mains electricity used in daily life is an alternating current with a sinusoidal waveform.<\/p>\n\n\n\n Direct current is an electric charge,\nusually electrons, flowing in one direction. The current density changes with\ntime, but the direction of movement is usually the same at all times. As an\nadjective, DC can be used as a reference voltage (its polarity will never\nchange).<\/p>\n\n\n\n In a DC circuit, electrons are formed from\nthe cathode, negative electrode, and negative magnetic pole, and move to the\nanode, positive electrode, and positive magnetic pole. <\/p>\n\n\n\n Direct current can be generated by\nelectrochemistry, photovoltaic cells or battery packs, or by rectification of\nalternating current. Alternating current can be converted to direct current\nthrough a power supply consisting of a converter, a rectifier (to prevent the\ncurrent from flowing in the opposite direction), and a filter (to eliminate the\njitter in the current flowing out of the rectifier).<\/p>\n\n\n\n Virtually all electronic and computer hardware require direct current to work. The demand for current ranges from close to zero in electronic watches to over 100 amperes required by wireless communication energy amplifiers. Devices that use vacuum tubes, such as high-energy radio or television broadcast transmitters or cathode ray tube (CRT) displays, require about 150 volts to several thousand volts of direct current.<\/p>\n\n\n\nThe origin of electricity<\/h2>\n\n\n\n
Alternating current(AC)<\/h2>\n\n\n\n
Direct current (DC)<\/h2>\n\n\n\n