ohm

Definitions

  • WordNet 3.6
    • n Ohm German physicist who formulated Ohm's law (1787-1854)
    • n ohm a unit of electrical resistance equal to the resistance between two points on a conductor when a potential difference of one volt between them produces a current of one ampere
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Webster's Revised Unabridged Dictionary
    • n Ohm ōm (Elec) The standard unit in the measure of electrical resistance, being the resistance of a circuit in which a potential difference of one volt produces a current of one ampére. As defined by the International Electrical Congress in 1893, and by United States Statute, it is a resistance substantially equal to 109 units of resistance of the C. G. S. system of electro-magnetic units, and is represented by the resistance offered to an unvarying electric current by a column of mercury at the temperature of melting ice 14.4521 grams in mass, of a constant cross-sectional area, and of the length of 106.3 centimeters. As thus defined it is called the international ohm.
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Century Dictionary and Cyclopedia
    • n ohm In electricity, the unit of resistance (see resistance). The theoretical or absolute ohm is equal to 10 centimeter-gram-second units of resistance (see unit). The practical ohm, until recently in use, was a resistance equal to that of a certain standard coil of wire (German silver) constructed under the direction of a Committee of the British Association in 1863, and hence often called the B. A. unit of resistance; it is a little less (0.987) than the true ohm. The legal or congress ohm, adopted by the Electrical Congress in 1884, is defined as the resistance at 0° C. of a column of pure mercury which is one square millimeter in cross-section and 106 centimeters in length; it is a very little less than the theoretical ohm. The Siemens unit is somewhat less than the ohm, being the resistance of a similar column just one meter in length. The resistance of a copper wire 1,000 feet long and one tenth of an inch in diameter is very nearly one ohm; a mile of ordinary iron telegraph-wire has a resistance of nearly 13 ohms.
    • n ohm An abbreviation of On His (or Her) Majesty's Service.
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Chambers's Twentieth Century Dictionary
    • n Ohm ōm the unit by which electrical resistance is measured, being nearly equal to that caused by a thousand feet of copper wire one-tenth of an inch in diameter
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Etymology

Webster's Revised Unabridged Dictionary
So called from the German electrician, G. S. Ohm,
Chambers's Twentieth Century Dictionary
Georg Simon Ohm, a German electrician, 1787-1854.

Usage

In literature:

The resistance of the two coils in series is about 10 ohms.
"The Elements of Bacteriological Technique" by John William Henry Eyre
By making 4 coils having, respectively, 1, 2, 2, and 5 Ohms resistance, you will be able to use any number of Ohms from 1 to 10.
"How Two Boys Made Their Own Electrical Apparatus" by Thomas M. (Thomas Matthew) St. John
Let ten or fifteen ohms of any convenient-sized wire be wound upon the bend of a commercial U-magnet.
"The Machinery of the Universe" by Amos Emerson Dolbear
A pair of watch-case receivers having a resistance of 1,000 ohms each, manufactured by a reliable firm.
"Boy Scouts Handbook" by Boy Scouts of America
Resistance is measured in ohms.
"The Automobile Storage Battery" by O. A. Witte
Suppose the internal resistance of the tube is 12,000 ohms and the resistance of the telephones is 3,000 ohms.
"Letters of a Radio-Engineer to His Son" by John Mills
F. is 0.153858 international ohms.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 8" by Various
Each supervisory relay is adapted, when energized, to close a 40-ohm shunt about its supervisory lamp.
"Cyclopedia of Telephony and Telegraphy, Vol. 2" by Kempster Miller
Normally, this resistance averages from seventy to eighty thousand ohms.
"The Social Gangster" by Arthur B. Reeve
When he made his discovery Ohm was working in the Gymnasium at Cologne.
"The Popes and Science" by James J. Walsh
Thus a cell of R = 250,000 ohms can be reduced to 60,000 ohms from the light of a 16 c.p.
"Wireless Transmission of Photographs" by Marcus J. Martin
Ordinary iron telegraph-wire measures about thirteen ohms to the mile.
"Electricity and Magnetism" by Elisha Gray
In order to stabilize the arc, a series resistance of a few ohms is necessary.
"The New Gresham Encyclopedia" by Various
So in Germany the Bille, Ohm, Orre, and Bordau, appear in charters of the 8th and 9th cent., as the Bilena, Amana, Oorana, and Bordine.
"The River-Names of Europe" by Robert Ferguson
Vich is der vay to 'Ohm, Sweet Ohm?
"Revisiting the Earth" by James Langdon Hill
All the voltmeters and ohmmeters mentioned owe their method of working to what is known as Ohm's law.
"Marvels of Scientific Invention" by Thomas W. Corbin
Ohm's law was first formally stated in 1827.
"Heroes of Science: Physicists" by William Garnett
The unit of resistance is known as an OHM.
"Electric Bells and All About Them" by S. R. Bottone
A well known mail carrier of early days was Nes Jacob Ohm or "Dutch Ned," as every one called him.
"Blazing The Way" by Emily Inez Denny
The resistance of some telephone receivers is 75 ohms, of a telegraph sounder, 4 ohms, of a relay 200 ohms.
"Physics" by Willis Eugene Tower
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In news:

Photos courtesy of OHM Above shows the staff of OHM 's Houghton office branch.
OHM Cycle Expands in Europe.
She was born Nov 5, 1963 in Hutchinson, the daughter of Loren and Patricia (Benton) Ohm .
OHM TO ACQUIRE BUSINESSES OF RUST INTERNATIONAL.
The OHM Corporation of Findlay, Ohio, agreed yesterday to buy the hazardous-waste and nuclear-waste cleaning businesses of Rust International Inc for about $72.6 million in stock.
Ohm 's Law and Torque.
In the course of my travels for many years now, it has become apparent that most electricians don't understand Ohm 's law, watts and torque.
Diameter and weighs just 0.7 g. They come in 34 standard Lohm (liquid ohm) rates from 3000 to 30,000 Lohms.
This sensor has a value of about 1.5 K ohms.
The Woodtick Wheelers ATV/OHM Club will host a spring ride in the State Forest on Saturday, June 5.
Ohm named president of digital voice tech firm HarQen.
Im new to the world of hifi audio, i currently own a marantz pm 7001 ki signature integrated amp , 70 watt rms - 4 ohm and 100 watt rms - 8 ohm, im looking to get new speakers for this amp , which one would you suggest.
The DA-2800 amplifier promises 2,800 watts into 4-ohm loads.
Sharon Prudhomme (PROOD'-ohm), who with her husband owns Prudhomme's Lost Cajun Kitchen in Columbia, Pa.
These 70Wpc tube amps contain two output transformers per amp and have two, four and eight ohm taps.
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In science:

L) = σLd−2 with conductivity σ (“the Ohm’s law”).
Scaling near random criticality in two-dimensional Dirac fermions
However, one can also use Ohm’s Law to compute the current, i.e. set ~J = σ( ~E + ~v/c × ~B ).
Magnetic Extraction of Spin Energy from a Black Hole
Thus, the resistive-MHD Ohm’s law immediately tells us that this configuration cannot be in a steady state.
Magnetic Interaction between Stars and Accretion Disks
Though Eq (2) is a relatively simple consequence of the basic "laws" of Ohm and Kirchoff in the theory of electricity it has profound consequences.
Review of Nonlinear Methods and Modelling
Eq (1) is essentially a continuum rendering of "Ohm’s law" U = RI ).
Review of Nonlinear Methods and Modelling
The kinematics of this weak flow are consistent with kinematics o f the brighter western jet (B ¨ohm & Solf 1999). T Tau S drives a remarkable jet (Reipurth et al. 1997; Walter et al. 2003).
Low Mass Star Formation in the Taurus-Auriga Clouds
The jet has a length of several arcsec, with a blueshifted southern lobe and a redshifted northern lobe (B ¨ohm & Solf 1994, 1997, 1999; Quirrenbach & Zinnecker 1997).
Low Mass Star Formation in the Taurus-Auriga Clouds
The magnetic field evolution is described by Faraday’s equation, with the electric field given by Ohm’s law.
Constrained-Transport Magnetohydrodynamics with Adaptive-Mesh-Refinement in CHARM
There are a number of modules being developed, including a module that can follow the ionization states of heavy elements and a module that introduces a modified Ohm’s law.
The stellar atmosphere simulation code Bifrost
We have seen above that the input impedance of the amplifier is typically a few tens of ohms and the output impedance a few hundred ohms. Thus the terminations of both the input and output lines are close to open-circuits.
RF power generation
This is a new finding in classical conductivity, in the area which seemed to be exhaustively explored shortly after Ohm’s discovery.
Generalized Ohm's law
They are no more complicated than Ohm’s law and possess in fact the similar structure.
Generalized Ohm's law
In introductory section I remind the reader the basics of Ohm’s approach and scattering approach to conductivity.
Generalized Ohm's law
The second section presents a microscopic derivation of the generalized Ohm’s law and shall be skipped by everyone who is not interested in such details.
Generalized Ohm's law
The important fourth section contains a concise formulation of the generalized Ohm’s law in terms of a circuit theory and shows how to deal with tunnel junctions and quantum point contacts.
Generalized Ohm's law
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