Elektricitetens historie i korte tr

Elektricitetens historie i korte træk
De tre store opdagelser

I elektricitetens historie er der tre særligt vigtige årstal:

bullet 1800 - Det første elektriske batteri blev lavet
bullet 1820 - Opdagelsen af elektromagnetismen
bullet 1831 - Opdagelsen af den elektromagnetiske induktion
Elektricitet

I Grækenland omkring 600 f.Kr. var man opmærksom på, at rav, der blev gnedet med uld, kunne tiltrække små fnug. Fænomenet blev kaldt elektricitet, fordi rav på græsk hedder elektron.

Magnetisme

Allerede i oldtiden kendte man en sten (en slags jernmalm), der kunne tiltrække jernstykker - i dag kalder vi den magnetjernsten. Man opdagede også tidligt, at man ved at stryge magnetjernsten hen ad en jernstang eller jernnål kunne gøre stangen eller nålen magnetisk.

Det ser ud til, at man har kendt brugen af magnetjernstenen som en slags kompas i flere tusinde år, men første omkring år 1600 fik man en beskrivelse (William Gilbert) af magnetisme og jorden som en kæmpemagnet.

Gilberts bog handler både om elektricitet og magnetisme og han beskriver forskelle på magnetiske kræfter og elektriske kræfter.

Maskiner laver elektricitet

På William Gilberts tid lavede man endnu kun elektricitet ved at gnide på rav og andre materialer med håndkraft. Men i 1670 konstruerede Otto von Guericke den første elektrisermaskine.

Han fandt bl.a. ud af, at elektricitet kunne gå igennem en hørtråd, og at den kunne lave gnister ('lyn').

De næste hundrede år efter von Guerickes opfindelse blev der lavet masser af lignende maskiner, og efterhånden blev de temmelig effektive.

For det meste blev elektrisermaskinerne brugt af adelsmænd som legetøj, men nogle undersøgte systematisk alle tænkelige fænomener, der opstod ved deres leg med apparaterne.

Stephan Grey fra England opdelte stoffer i gode og dårlige ledere.

Franskmanden Charles Dufay opdagede, der var to slags elektricitet, glas-elektricitet og lak-elektricitet. Og han fandt ud af, at kugler med ens elektricitet frastøder hinanden, mens kugler med forskellig slags elektricitet tiltrækker hinanden.

I 1744 fandt Leyden ud af at gemme elektricitet i en metalcylinder nede i et glas. Det blev til kondensatoren - en meget vigtig komponent i alverdens elektriske og elektroniske apparater.

I 1745 og årene der efter eksperimenterede amerikaneren Benjamin Franklin med elektricitet. Han fremsatte blandt meget andet teorier, hvor han brugte begreberne positiv og negativ elektricitet. Det, han blev mest kendt for, var dog nok, at han sendte en drage op i tordenvejr og 'trak elektriciteten ud' af dragesnoren med en finger - andre, der prøvede det samme, trak for store gnister ud og døde af det.

Sidste skud på elektrisermaskinens udvikling kom i 1933, en van de Graaf, opkaldt efter dens amerikanske opfinder. Med den kan man nå op på over 10 millioner volt, og den er blevet brugt i forbindelse med atomkernefysikken. En lille udgave af van de Graaf 'en står i de fleste fysiksamlinger i dag.

Batteriet

De mange mere eller mindre fantasifulde apparater, der blev opfundet i forbindelse med elektrisermaskine, havde ét til fælles: De var stort set ubrugelige til noget praktisk formål.

Imidlertid skete der noget spændende i Italien omkring 1790. Lægen Galvani eksperimenterede med opsprættede frøer, og han opdagede, at når han rørte ved et frølår med to redskaber af forskellige metaller, så spjættede frølåret!

På baggrund af Galvanis forsøg opfandt hans landsmand Volta batteriet i 1800.

Det bestod af skiftevis kobber- og zinkplader med syrevædet filt imellem.

Nu kunne man få en konstant elektrisk strøm gennem længere tid og med en lav spænding (under 100V), hvor elektrisermaskine frembragte meget høj spænding (hundrede tusinder volt).

Den nye opfindelse satte gang i alle andre 'Ole Opfindere' og i de nysgerrige videnskabsmænd.

Elektrolyse af en mængde væsker og nye teorier herom gav i første halvdel af 1800-tallet stødet til bedre batterier, 'stamfædrene' til vore dages batterier.

Elektromagnetisme

I årene forud for 1820 eksperimenterede vor landsmand H.C. Ørsted med voltabatterier, ledninger og magnetnåle (kompas). Han opdagede, at strøm gennem en metaltråd fik en magnetnål til at slå ud, når tråden var i nærheden. I 1820 udgiver han på den baggrund en bog om sine studier og teorier.

Det var en ny revolutionerende opdagelse. Indtil da havde man opfattet elektricitet og magnetisme som to helt uafhængige ting.

På baggrund af Ørsteds forsøg blev elektromagneter opfundet, og derefter en mængde apparater, hvor de kunne bruges: Motorer, ringeapparater, morseapparater osv.

Induktion

Den engelske videnskabsmand, Faraday, havde studeret Ørsteds værk fra 1820, og han grubler i flere år over problemet:

bullet Når elektrisk strøm kan frembringe magnetisme, må magnetisme også kunne fremkalde elektricitet.
I 1831 lykkedes det ham at lave en slags transformator, hvor han ved magnetismens hjælp kunne 'overføre' strøm fra en vikling på en jernring til en anden. Han kunne også frembringe svag strøm ved hurtigt at føre en fast magnet ned i en spole - i sandhed en vigtig opdagelse: Det spæde grundlag for dynamoen, generatoren, og el-kraftværker var skabt.

Nu var de tre afgørende opdagelser gjort:

bullet Det galvaniske element (batteriet).
bullet Elektromagnetisme og elektromagneter.
bullet Induktion - at lave elektrisk strøm ved hjælp af magnetisme.
Fra midten af 1800-tallet gik det hurtigt. Mange opfindere og videnskabsmænd så perspektivet i de tre store opdagelser.

De vigtigste opfindelser:

I årene efter Faradays induktionsforsøg blev der lavet mange eksperimenter med generatorer ('magneto-elektriske maskiner'). Det blev en kæmpe fordel frem for batterier: Batterierne mistede hurtigt 'kraften', mens dynamoen/generatoren kunne køre i timevis, ja, dag efter dag, og stadig give 'god strøm'.

I 1851 blev Ruhmkorffs gnistinduktionsmaskine opfundet, et induktionsapparat, der konstant kunne trække en elektrisk gnist mellem to metalspidser. I dag kender vi bl.a. princippet fra tændspoler til biler og fra spændingsforsyning til røntgenapparater.

I 1833 blev det første elektromagnetisk telegrafapparat lavet. Allerede tilbage i begyndelsen af århundredet havde opfindsomme hoveder konstrueret sindrige elektriske telegrafapparater, der var baseret på elektrolyse af vand i små beholdere, ét for hvert bogstav. Disse apparater fik aldrig nogen særlig betydning. Det gjorde derimod apparatet baseret på elektromagneten!

I 1844 indførte amerikaneren Samuel Morse sit nye telegrafisystem. Det system viste sig at være så godt, at det stadig bliver brugt 150 år efter!

I 1860 blev den første telefon lavet af tyskeren Philip Reiss.

Den var ikke særlig god. Så det blev amerikaneren Graham Bell, der konstruerede de første brugbare telefoner, stadig lavet efter Reisses princip.

Kulkornsmikrofonen, der også bruges i dag, blev opfundet noget senere af amerikaneren Thomas Edison.

Telegrafen og telefonen revolutionerede nyhedsformidlingen, forretningsforbindelser og anden form for kommunikation. Der blev gravet kabler ned og lavet master med telegraf/telefonledninger i hele den moderne verden og mellem verdensdelene. Man kunne nu sende meddelelser og nyheder med minutters varsel, og forretningsaftaler kunne omgående laves mellem folk i alverdens lande!

Grammofonen blev opfundet i 1877 af Edison.

Den elektromagnetiske lydoptager (forgængeren for båndoptageren) blev opfundet i 1898 af danskeren Valdemar Poulsen. Den fik dog først betydning, da man i 1921 blev i stand til at forstærke de svage signaler.

Forskellige former for lamper blev opfundet. Helt tilbage til voltabatteriets tid, omkring 1811, kunne man lave en lysbue ved lige at lade spidserne af to kulstænger røre hinanden, og så derefter fjerne dem ganske lidt fra hinanden. Lyset er meget kraftigt og det kunne bruges i fyrtårne og på åbne pladser, men ikke ret godt indendørs. Den dansk-færøske læge Niels Finsen fandt i 1895 på at bruge lyset, der indeholdt meget UV-stråling til at helbrede hudtuberkulose.

Ved hjælp af induktionsapparatet kunne man sende strøm gennem fortyndet luft i et glasrør. Forskellig luftarter gav forskellige farver. Disse eksperimenter affødte vigtige opdagelser: radiorør, lysstofrør, røntgenrør mv.

Det store gennembrud på belysningsområdet kom i 1879, hvor Thomas Edison opfandt glødelampen på den kendte sokkel. Den gav behagelig lys og var nem at håndtere. De første glødelamper var med kulglødetråd. Den blev videreudviklet de følgende årtier, og den nuværende type med wolframtråd og gasfyldt 'glashus' blev lavet i 1913.

De første lysstofrør blev taget i brug omkring 1940. Lysstofrør har den fordel, at de giver mere lys for pengene - der går ikke så meget af energien til varme, som der gør i glødelampen.

Allerede i 1888 påviste tyskeren Heinrich Hertz, at 'elektrisk energi kunne gå gennem luften' uden ledninger. Italieneren Marconi tog ideen op og lavede det første trådløse telegrafapparat. Danskeren Valdemar Poulsen var også med på vognen. Han lavede i 1902 det første apparat, der kunne frembringe konstante, hurtige elektriske svingninger. Hans opfindelse blev snart brugt over hele verden til radiotelefoni.

Omkring 1920 dukkede mange sendere op i Danmark, og de følgende år blev radioen udbredt over hele den industrielle verden.

De første spæde forsøg på billedtelegrafi blev gjort af tyskeren Paul Nipkow så tidligt som i 1883.

De næste årtier udvikledes ideen, og den fik sit gennembrud med katodestrålerørets opfindelse. I 1926 startede BBC de første TV-prøveudsendelser!

Transistoren, radiorørets afløser, blev opfundet i 1948. Den blev snart udviklet, så den kunne overtage flere og flere af det gamle radiorørs funktioner. I 1960'erne forsvandt radiorøret næsten fra scenen. Transistoren fyldte, i modsætning til det gamle radiorør, næsten ingenting og brugte meget lidt energi.

Opfindelsen af transistoren førte til en hurtig udvikling af elektroniske regnemaskiner og senere, da man fandt ud af at lave integrerede kredsløb, computere.

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Resultater (Engelsk) 1:

Regardless of the history in briefThe three major discoveriesIn explaining the history, there are three particularly important years:bullet 1800-The first electric battery was createdbullet 1820-discovery of electromagnetismbullet 1831-the discovery of electromagnetic inductionElectricityIn Greece around 600 BC were you aware that Amber was rubbed with wool, could attract small fluff. The phenomenon was called electricity, because amber is called elektron in Greek.MagnetismAlready in ancient times known to a stone (a form of iron ore), which could attract iron pieces-today we call the magnet iron stone. We also discovered early that by ironing the magnetic iron rocks along an iron bar or jernnål could do the pole or needle magnetic.It seems that you have known the use of magnet iron stone as a kind of compass in several thousand years, but first around the year 1600, a description (William Gilbert) of magnetism and the Earth as a giant magnet.Gilbert's book is both about electricity and magnetism, and he describes the differences in the magnetic forces and electric forces.Machines make electricityOn William Gilbert's time did we even only electricity by rubbing of amber and other materials by hand. But in 1670 contrived Otto von Guericke, the first elektrisermaskine.He found, among other things. out of that electricity could go through a hørtråd, and it might make Sparks (' lightning ').The next hundred years after von Guericke has invention were made lots of similar machines, and eventually they were pretty effective.For the most part was elektrisermaskinerne used by noblemen as toys, but some were investigated systematically all possible phenomena that occurred during their play with the appliances.Stephan Grey from England split substances into good and bad leaders.Frenchman Charles Dufay discovered, there were two kinds of electricity, glass and lacquer-electricity-electricity. And he found out that the balls with the same electricity repel each other, while spheres with different kind of electricity attract each other.In 1744 found Leyden out of saving electricity in a metal cylinder down into a glass. It was for the capacitor-a very important component in all your electrical and electronic appliances.In 1745 and the years after the American Benjamin Franklin experimented with electricity. He made among other theories, where he used the concepts of positive and negative electricity. What he was most famous for, however, was enough that he sent a go up in a thunderstorm and electricity pulled out ' of ' draw the string with a finger-others who tried the same, pulled for large sparks off and died of it.Last shot at elektrisermaskinens development came in 1933, a van de Graaf, named after its American inventor. With it you can reach over 10 million volts, and it has been used in connection with atomkerne physics. A small version of the van de Graaf's a stand in most physics collections today.BatteryThe many more or less imaginative apparatus was invented in connection with elektrisermaskine, had one in common: they were pretty much useless for any practical purpose.However, there was something exciting in Italy around 1790. Doctor Galvani experimented with opsprættede frogs, and he discovered that when he touched a frog legs with two gears of various metals, then twitched frølåret!In the light of the Galvanis trials invented his compatriot Volta battery in 1800.It consisted of alternating copper and zinc plates with acid-soaked felt in a while.Now you could get a constant electric current through a longer period of time and with a low voltage (less than 100V), where elektrisermaskine produced very high voltages (hundreds of thousands of volts).The new invention sparked the all other ' Ole Inventors ' and in the curious scientists.Electrolysis of a quantity of liquids and new theories about this gave in the first half of the 19th century, the impetus for better batteries, ' stem the fathers ' to today's batteries.ElectromagnetismIn the years prior to 1820 experimented our compatriot Hans Christian Ørsted with volta batteries, wires and magnetic needles (compass). He discovered that the current through a wire got a magnetnål to turn off when the thread was nearby. In 1820 he publishes in the light of this, a book about his studies and theories.It was a new revolutionary discovery. Until then they had seen electricity and magnetism as two totally unrelated things.On the basis of Ørsted's experiments were electromagnets invented, and then a quantity of appliances, where they could be used: Motors, small appliances, morse machines etc.InductionThe English scientist, Faraday, had studied Ørsted's work from 1820, and he mulls over the problem for several years:bullet When electric current can produce magnetism, magnetism must also be able to produce electricity.In 1831, he managed to make a kind of transformer, where he knows magnet of help could ' migrate ' power from a winding on a iron ring to another. He could also produce weak power by quickly implementing a permanent magnet in a coil-truly an important discovery: The early basis for the Dynamo, the generator, and electric power plants was created.Now they were three crucial discoveries:bullet The galvanic element (battery).bullet electromagnetism and electromagnets.bullet Induction-to make electric power using magnetism.From the mid-19th century it went quickly. Many inventors and scientists so the perspective in the three major discoveries.The most important inventions:In the years after Faraday's induction experiments were made many experiments with generators (' magneto-electric machines '). It was a huge advantage over batteries: the batteries quickly lost ' the power ', while the Dynamo/alternator could run for hours, Yes, day after day, and still give ' good power '.In 1851 was Ruhmkorffs spark induction machine invented, an induction machine, that constant could pull an electric spark between the two metal ends. Today we know, among other things. principle of ignition coils for cars and from the voltage supply for x-ray apparatus.In 1833 became the first electromagnetic Telegraph machine made. Already back in the beginning of the century had inventive heads designed ingenious electric telegraph apparatus was based on electrolysis of water in small containers, one for each letter. These devices never got any special significance. It did on the other hand, the appliance based on elektromagneten!In 1844 the Explorer Samuel Morse introduced his new telegraph system. The system proved to be so good that it's still being used 150 years after!In 1860 was the first telephone made by German Philip Reiss.It was not very good. So it was the American Graham Bell, who constructed the first usable phones, still made after Reisses principle.Kulkorns the microphone that is also used today was invented somewhat later by the American Thomas Edison.The Telegraph and the telephone revolutionized news dissemination, business relationships and other forms of communication. There were dug cables down and created master with Telegraph/telephone wires throughout the modern world and between the world's parts. You can now send messages and news with minutes notice, and business deals could immediately be made between people in all your countries!The gramophone was invented in 1877 by Edison.The electromagnetic sound recorder (the predecessor of the tape recorder) was invented in 1898 by Valdemar Dane Poulsen. It was, however, first importance, since one in 1921 were able to amplify weak signals.Various types of lamps were invented. All the way back to the volta battery time, around 1811, one could make an arc by just letting the tips of two kulstænger touch each other, and then remove them quite a bit from each other. The light is very strong and it could be used in lighthouses and on open spaces, but not very well indoors. The Danish-Faroese doctor Niels Finsen found in 1895 to use light, which contained much UV radiation to cure hudtuberkulose.Using induction apparatus, one could send power through diluted air in a glass tube. Different gases gave different colors. These experiments spawned important discoveries: radio tubes, fluorescent lamps, x-ray tubes, etc.The major breakthrough in lighting area came in 1879, where Thomas Edison invented the incandescent lamp on the well-known socket. It gave a pleasant light and was easy to handle. The first was with incandescent kulglødetråd. It was further developed the following decades, and the current type of tungsten wire and gas-filled ' glass house ' was created in 1913.The first fluorescent lamps were put into use around 1940. Fluorescent lamps have the advantage that they provide more light for money-that is just not so much of the energy to heat, which makes of the filament lamp.As early as 1888 the German Heinrich Hertz demonstrated that ' could go through the air ' electrical energy without wires. The Italian Marconi took the idea up and made the first wireless telegraph apparatus. The Dane Valdemar Poulsen was also on board. He made in 1902 the first appliance that can generate steady, rapid electrical oscillations. His invention was soon used all over the world for radio-telephony.Around 1920 showed many transmitters up in Denmark, and the following year was the radio widespread throughout the industrial world.The first fledgling attempts picture telegraphy was done by German Paul Nipkow as early as 1883.The next few decades developed the idea, and it got its breakthrough with invention of the cathode ray tube. In 1926 the first BBC television started test broadcasts!The transistor radio, pipe replacement, was invented in 1948. It was soon developed, so that it could take over more and more of the old radio tube features. In the 1960s radio tube almost disappeared from the scene. The transistor filled, as opposed to the old radio tubes, almost nothing and used very little energy.The invention of the transistor, led to a rapid development of electronic calculators and later, when we found out how to make integrated circuits, computers.Kik you

Resultater (Engelsk) 2:

Electricity brief history of
the three great discoveries in the history of electricity, there are three very important years: bullet 1800 - The first electric battery was made ​​bullet 1820 - The discovery of electromagnetism bullet 1831 - The discovery of electromagnetic induction Electricity In Greece, about 600 f.Kr . were you aware that amber rubbed with wool could attract small fluff. The phenomenon was called electricity because amber in Greek is called electron. Magnetism Already in ancient times was known a stone (a type of iron ore) which could attract iron pieces - today we call it magnetic iron stone. It was also discovered early that by swiping the magnetic iron stone along an iron bar or jernnål could make the rod or needle magnetic. It seems that one has known the use of magnetic iron stone as a kind of compass for several thousand years, but first around 1600 you got a description (William Gilbert) of magnetism and the Earth as a giant magnet. Gilbert's book is about both electricity and magnetism and he describes the differences in the magnetic forces and electrical forces. Machinery make electricity on William Gilbert's time they made ​​yet only electricity by rubbing the amber and other materials by hand. But in 1670 engineered Otto von Guericke the first elektrisermaskine. He found, inter alia, out of that electricity could go through a linen thread, and that it could make sparks (lightning). The next hundred years after von Guerickes invention was made ​​lots of similar machines, and gradually they were pretty effective. For the most part was elektrisermaskinerne used by noble men like toys, but some systematically examined all possible phenomena that arose from their play with the appliances. Stephan Grey from England divided substances in good and bad leaders. The Frenchman Charles Dufay discovered there were two kinds of electricity, glass-electricity and lacquer-electricity. And he found out that the balls of the same electricity repel each other, while the balls of the various kinds of electricity attract each other. In 1744 Leyden found out how to store electricity in a metal cylinder down in a glass. It was to the condenser - a very important component in all sorts of electrical and electronic appliances. In 1745 and the years after experimented American Benjamin Franklin with electricity. He made ​​among many other theories in which he used the concepts of positive and negative electricity. What he was most famous for, however, was enough that he sent a kite in a thunderstorm and 'pulled electricity out' of kite string with a finger - others who tried it immediately drew large sparks out and died of it. Last shot at elektrisermaskinens development came in 1933, a van de Graaf, named after its American inventor. With it, you can reach over 10 million volts, and it has been used in connection with the atomic nucleus physics. A small version of the Van de Graaff 'one stands in most physics collections today. The battery of the many more or less imaginative devices were invented in connection with elektrisermaskine, had one thing in common: They were virtually useless for any practical purpose. However, there was something exciting in Italy around 1790. The physician Galvani experimented with slitted frogs, and he discovered that when he touched a frog legs with two tools of different metals, then twitched frølåret! Based on Galvani's experiments invented his compatriot Volta battery in 1800 . It consisted of alternating copper and zinc plates syrevædet felt in a while. Now you could get a constant electric power for a long time and with a low voltage (below 100V) where elektrisermaskine produced very high voltage (hundreds of thousands of volts). The new invention sparked all other 'Ole Inventors' and in the curious scientists. Electrolysis of a quantity of fluids and new theories accordingly gave in the first half of the 1800s, the impetus for better batteries, 'ancestors' of today's batteries. Electromagnetism In the years prior to the 1820 experimented our compatriot Hans Christian Oersted with voltaic batteries, wire and magnet needle (compass). He discovered that current through a wire was a magnetic needle to turn out when the thread was nearby. In 1820 he publishes on the background a book about his studies and theories. It was a new revolutionary discovery. Until then they had seen electricity and magnetism as two totally unrelated things. Based on Ørsteds attempt was electromagnets invented and then a quantity of appliances where they could be used: Engines, bells, mother appliances etc. Induction The English scientist Faraday, had studied Ørsteds work from 1820, and he ponders for several years about the problem: bullet When electric current produced magnetism, the magnetism could also produce electricity. In 1831, he managed to make a kind of transformer, where he magnetismens help could 'transfer' power from a winding on an iron ring to another. He could also produce low voltage by quickly passing a permanent magnet into a coil - truly an important discovery: The tentative basis for the dynamo, generator and electric power plants was created. Now they were three crucial discoveries: bullet It galvanic element (battery). bullet Electromagnetism and electromagnets. bullet Induction - to make electric power using magnetism. From the mid-1800s it went quickly. Many inventors and scientists as the perspective of the three major discoveries. The most important innovations: In the years after Faraday induktionsforsøg was made ​​many experiments with generators (magneto-electric machines'). It was a huge advantage over batteries: The batteries quickly lost 'power', while the alternator / generator could run for hours, yes, day after day, and still provide 'good power'. In 1851 Ruhmkorffs gnistinduktionsmaskine invented a induktionsapparat that constantly able to draw an electrical spark between two metal spikes. Today we know among others the principle of ignition coils for automobiles and from the power supply to the X-ray machines. In 1833, the first electromagnetic telegraph apparatus made. Already back at the beginning of the century had inventive minds constructed ingenious electric telegraph apparatus, which was based on the electrolysis of water in small containers, one for each letter. These devices never got any special significance. It made ​​the other hand the device based on the electromagnet! In 1844 introduced American Samuel Morse his new telegrafisystem. The system proved to be so good that it is still being used 150 years after! In 1860, the first phone made ​​by the German Philip Reiss. It was not very good. So it was the American Graham Bell, who constructed the first usable phones are still made ​​by Reisses principle. Kulkornsmikrofonen, also used today, was invented somewhat later by the American Thomas Edison. The telegraph and the telephone revolutionized news reporting, business associates and other communications. There were dug cables down and made ​​master with telegraph / telephone lines throughout the modern world and between the continents. You could now send messages and news with minute warning, and business agreements could immediately be made ​​between people all over the world! The phonograph was invented in 1877 by Edison. The electromagnetic sound recorder (formerly VCR) was invented in 1898 by the Dane Valdemar Poulsen. It was not until importance because in 1921 were able to amplify the weak signals. Different types of lamps were invented. Way back to voltaic battery time, about 1811, one could make an arc of just letting the tips of two kulstænger touch each other, and so then remove them slightly apart. The light is very strong and it could be used in lighthouses and on open spaces, but not quite well indoors. The Danish-Faroe doctor Niels Finsen found in 1895 to use the light containing much UV radiation to cure skin tuberculosis. By means of induktionsapparatet could send current through the diluted air in a glass tube. Different gases gave different colors. These experiments gave rise to important discoveries: radio tubes, fluorescent, X-ray tubes, etc. The major breakthrough in lighting came in 1879, when Thomas Edison invented the incandescent lamp on the known base. It gave pleasant light and was easy to handle. The first incandescent lamps were with kulglødetråd. It was developed the following decades, and the current type of tungsten and gas-filled 'glass house' was made ​​in 1913. The first fluorescent lamp came into use around 1940. Fluorescent lamps have the advantage that they provide more light for the money - that goes not so much of the energy to heat, which makes the incandescent lamp. Already in 1888 showed the German Heinrich Hertz that 'electrical energy could go through the air' without wires. The Italian Marconi took up the idea and made ​​the first wireless telegraph apparatus. Dane Valdemar Poulsen was also on board. He made ​​in 1902, the first device that could produce constant, rapid electrical oscillations. His invention was soon used throughout the world for radio. Around 1920 appeared transmitters up in Denmark, and the following year was the radio prevalent throughout the industrial world. The first tentative attempts billedtelegrafi was made ​​by German Paul Nipkow as early as in 1883 . The next decades developed the idea and had his breakthrough with the CRT invention. In 1926 the BBC started the first TV test broadcasts! Transistor, radiorørets successor, was invented in 1948. It was soon developed so that it could take over more and more of the old radiorørs functions. In the 1960s disappeared radio tube almost from the scene. The transistor age, in contrast to the old radio tubes, almost nothing and used very little energy. The invention of the transistor led to the rapid development of electronic calculators and later, when they found out how to make integrated circuits, computers. Look you

Resultater (Engelsk) 3:

Electricity history in brief
the three great discoveries in electricity History

there are three particularly important year:

bullet 1800 - The first electric battery was made
bullet 1820 - Discovery as determined by
bullet 1831 - discovery of the electromagnetic induction
electricity

in Greece around 600 B.C. it was aware that amber, which was rubbed with wool,