Edwin Herbert Hall (November 7, 1855 – November 20, 1938) was an American physicist, who discovered the eponymous
Hall effect
The Hall effect is the production of a voltage difference (the Hall voltage) across an electrical conductor that is transverse to an electric current in the conductor and to an applied magnetic field perpendicular to the current. It was disco ...
. Hall conducted
thermoelectric
The thermoelectric effect is the direct conversion of temperature differences to electric voltage and vice versa via a thermocouple. A thermoelectric device creates a voltage when there is a different temperature on each side. Conversely, when ...
research
Research is "creativity, creative and systematic work undertaken to increase the stock of knowledge". It involves the collection, organization and analysis of evidence to increase understanding of a topic, characterized by a particular att ...
and also wrote numerous physics textbooks and laboratory manuals.
Biography
Hall was born in
Gorham, Maine
Gorham is a town in Cumberland County, Maine, United States. The population was 18,336 at the 2020 United States Census. In addition to its urban village center known as Gorham Village or simply "the Village," the town encompasses a number of ...
,
U.S.
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...
Hall did his undergraduate work at
Bowdoin College
Bowdoin College ( ) is a private liberal arts college in Brunswick, Maine. When Bowdoin was chartered in 1794, Maine was still a part of the Commonwealth of Massachusetts. The college offers 34 majors and 36 minors, as well as several joint eng ...
,
Brunswick, Maine
Brunswick is a town in Cumberland County, Maine, United States. The population was 21,756 at the 2020 United States Census. Part of the Portland-South Portland-Biddeford metropolitan area, Brunswick is home to Bowdoin College, the Bowdoin Intern ...
, graduating in 1875. He was the principal of
Gould Academy
Gould Academy is a private, co-ed, college preparatory boarding and day school founded in 1836 and located in the small town of Bethel, Maine, United States.
History
In 1835 citizens of Bethel, Maine, formed an organization as trustees of the ...
in 1875–1876 and the principal of
Brunswick High School in 1876–1877.
He did his graduate schooling and research, and earned his
Ph.D.
A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...
degree (1880), at the
Johns Hopkins University
Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...
where his seminal experiments were performed.
The Hall effect was discovered by Hall in 1879, while working on his doctoral thesis in Physics under the supervision of
Henry Augustus Rowland
Henry Augustus Rowland (November 27, 1848 – April 16, 1901) was an American physicist and Johns Hopkins educator. Between 1899 and 1901 he served as the first president of the American Physical Society. He is remembered primarily for the h ...
.
Hall's experiments consisted of exposing thin
gold leaf
Gold leaf is gold that has been hammered into thin sheets (usually around 0.1 µm thick) by goldbeating and is often used for gilding. Gold leaf is available in a wide variety of karats and shades. The most commonly used gold is 22-kara ...
(and, later, using various other materials) on a
glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of ...
plate and tapping off the gold leaf at points down its length. The effect is a
potential difference
Voltage, also known as electric pressure, electric tension, or (electric) potential difference, is the difference in electric potential between two points. In a static electric field, it corresponds to the work needed per unit of charge to m ...
(Hall voltage) on opposite sides of a thin sheet of conducting or semiconducting material (the Hall element) through which an
electric current
An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is measured as the net rate of flow of electric charge through a surface or into a control volume. The moving pa ...
is flowing. This was created by a
magnetic field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...
applied perpendicular to the Hall element. The ratio of the voltage created to the amount of current is known as the ''Hall resistance'', and is a characteristic of the material in the element. In 1880, Hall's experimentation was published as a doctoral thesis in the
American Journal of Science and in the
Philosophical Magazine
The ''Philosophical Magazine'' is one of the oldest scientific journals published in English. It was established by Alexander Tilloch in 1798;John Burnett"Tilloch, Alexander (1759–1825)" Oxford Dictionary of National Biography, Oxford Univer ...
.
Hall was appointed as a
professor
Professor (commonly abbreviated as Prof.) is an Academy, academic rank at university, universities and other post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin as a "person who pr ...
of physics at Harvard in 1895, and succeeded
John Trowbridge as
Rumford Professor of Physics in 1914.
[ Hall retired in 1921 and died in ]Cambridge, Massachusetts
Cambridge ( ) is a city in Middlesex County, Massachusetts, United States. As part of the Boston metropolitan area, the cities population of the 2020 U.S. census was 118,403, making it the fourth most populous city in the state, behind Boston, ...
, U.S.
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...
in 1938.
The Hall effect is used in magnetic field sensors, present in a large number of devices, as well as high efficiency electric propulsion systems on spacecraft.
In the presence of large magnetic field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...
strength and low temperature
Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer.
Thermometers are calibrated in various temperature scales that historically have relied o ...
, one can observe the quantum Hall effect
The quantum Hall effect (or integer quantum Hall effect) is a quantized version of the Hall effect which is observed in two-dimensional electron systems subjected to low temperatures and strong magnetic fields, in which the Hall resistance exh ...
, which is the quantization of the Hall resistance. This is now the official standard for electrical resistance.
Works
He made various contributions to scientific journals on the thermal conductivity of iron and nickel, the theory of thermoelectric action, and on thermoelectric heterogeneity in metals. His publications include:
''A Text-Book of Physics''
(1891; third edition, 1903), with J. Y. Bergen
''Elementary Lessons in Physics''
(1894; 1900)
* ''The Teaching of Chemistry and Physics'' (1902), with Alexander Smith
* ''College Laboratory Manual of Physics'' (1904; revised edition, 1913)
* ''Elements of Physics'' (1912)
See also
* Hall effect
The Hall effect is the production of a voltage difference (the Hall voltage) across an electrical conductor that is transverse to an electric current in the conductor and to an applied magnetic field perpendicular to the current. It was disco ...
* Henry Augustus Rowland
Henry Augustus Rowland (November 27, 1848 – April 16, 1901) was an American physicist and Johns Hopkins educator. Between 1899 and 1901 he served as the first president of the American Physical Society. He is remembered primarily for the h ...
* Scientific phenomena named after people
This is a list of scientific phenomena and concepts named after people (eponymous phenomena). For other lists of eponyms, see eponym.
A
* Abderhalden–Fauser reaction – Emil Abderhalden and August Fauser (1856–1938)
* Abney effect – ...
Relevant lists
* List of eponyms
A ''list'' is any set of items in a row. List or lists may also refer to:
People
* List (surname)
Organizations
* List College, an undergraduate division of the Jewish Theological Seminary of America
* SC Germania List, German rugby unio ...
* List of physicists
Following is a list of physicists who are notable for their achievements.
A
*Jules Aarons – United States (1921–2016)
*Ernst Karl Abbe – Germany (1840–1905)
*Derek Abbott – Australia (born 1960)
*Hasan Abdullayev – Azerbaijan Demo ...
References
External links
* Katz, Eugenii,
Hall
. Biosensors & Bioelectronics.
* The President and Fellows of Harvard College,
. Houghton Library, Harvard College Library, Harvard University, Cambridge, MA. 2002.
*
Edwin Hall image
. aip.org.
* Hall, Edwin,
. ''American Journal of Mathematics'' vol. 2 pp. 287–292, 1879.
*
{{DEFAULTSORT:Hall, Edwin
1855 births
1938 deaths
American physicists
Hall effect
People from Gorham, Maine
Bowdoin College alumni
Johns Hopkins University alumni
Harvard University faculty
Burials at Mount Auburn Cemetery