Chinese name? Cold words
Mbth？ Heinrich Friedrich Emil Leng Ci
Nationality? Russia
Birthplace Estonia
Date of birth:1February 24th, 804.
Date of death: 1865 February 10.
Occupation? physicist
Dopat University Graduate School
Major achievements? The Lenz law of electromagnetic induction and Joule-Lenz law of electrothermal effect were discovered.
Lenz (Heinrich Friedrich Emil)1804 (Jiazi Year) was born in Estonia on February 24th. 16 years old, admitted to his hometown Daupat University with excellent results. 1828 was elected as the junior scientific assistant of Russian Academy of Sciences in St. Petersburg, and 1830 was elected as the communication academician of St. Petersburg Academy of Sciences. He served as the head of the Department of Physical Mathematics of St. Petersburg University for a long time, and was elected as the first president by the Professors Association.
Lengci's main achievement in physics is the discovery of Lenz's law of electromagnetic induction and Joule-Lenz's law of electrothermal effect.
1833, Lengci read his paper entitled "Determining the direction of induced current by electrodynamics" in St. Petersburg Academy of Sciences and put forward Lenz's law. Helmholtz proved that Lenz's law is electromagnetic phenomena's law of conservation of energy.
In terms of electric heating, 1843, Lengci discovered this law independently without knowing that Joule discovered it (184 1 year). He improved the experimental method and used alcohol as the heat transfer medium, which improved the accuracy of the experiment.
In 183 1, Lengci made a quantitative study on electromagnetic phenomena according to the instantaneous and electric shock-like effects of induced current, and determined that the induced electromotive force in the coil is equal to the sum of electromotive force in each turn, regardless of the thickness and type of wires used. In 1838, Lengci also studied the conversion between motor and generator, and explained its conversion principle with Lenz's law. 1844, when Lengci studied the parallel connection of arbitrary electromotive force and resistance, he got the law of shunt current, which was four years earlier than Kirchhoff's more general circuit law.
1865 During the winter vacation, Lengci died of a stroke in Rome.
An Important Contribution to Physics-Lenz's Law
Lenz's law is a law of electromagnetism, and the direction of induced electromotive force is obtained by electromagnetic induction.
The magnetic field of induced current always hinders the change of magnetic flux that causes induced current.
Note: "Obstruction" is not "opposite", the direction is opposite when the original magnetic flux increases, and the direction is the same when the original magnetic flux decreases; "Obstruction" is not a blockage, and the magnetic flux in the circuit is still changing.
The formula is: e = nφ/△ t.
Where e is the induced electromotive force, n is the number of coils, and φ is the magnetic flux.
1833 On the basis of summarizing a large number of experimental facts, Lengci summed up a law for judging the direction of induced current, which is called Lenz's law.
Lenz's law can be expressed as follows: the direction of induced current in a closed loop always makes the magnetic field excited by it hinder the change of magnetic flux that causes induced current.
Lenz's law can also be simply expressed as: the role of induced current is always the reason that hinders the generation of induced current.