impedance
Americannoun
-
Electricity. the total opposition to alternating current by an electric circuit, equal to the square root of the sum of the squares of the resistance and reactance of the circuit and usually expressed in ohms. Z
-
Also called mechanical impedance. Physics. the ratio of the force on a system undergoing simple harmonic motion to the velocity of the particles in the system.
-
something that impedes; an obstacle or hindrance.
noun
-
Z. a measure of the opposition to the flow of an alternating current equal to the square root of the sum of the squares of the resistance and the reactance, expressed in ohms
-
a component that offers impedance
-
Also called: acoustic impedance. Za. the ratio of the sound pressure in a medium to the rate of alternating flow of the medium through a specified surface due to the sound wave
-
Also called: mechanical impedance. Zm. the ratio of the mechanical force, acting in the direction of motion, to the velocity of the resulting vibration
-
A measure of the opposition to the flow of alternating current through a circuit. Impedance is measured in ohms. The resistance of a circuit to direct current (also measured in ohms) is generally not the same as its impedance, due to the effects of capacitance and induction in and among the components of the circuit.
-
See also impedance matching
Discover More
The term impedance is most often encountered in dealing with antennas and speakers in television, stereo, and radio systems.
Other Word Forms
- self-impedance noun
Etymology
Origin of impedance
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Pulse wave velocity was measured by impedance cardiography, while carotid intima-media thickness and carotid artery distensibility were measured by carotid ultrasonography.
From Science Daily
Martin is a multifaceted talent in the studio, as well versed in terms like “impedance” and “gain staging” as he is with microphones and composition.
From Los Angeles Times
One of the resonators enables the light coming from the laser to couple with the other resonator; rather like impedance matching in electronics.
From Science Daily
Then there are people whose acid reflux is severe, as measured by the pH impedance study, and despite taking PPIs correctly, still experience painful, breakthrough heartburn.
From Washington Post
That’s similar to what I get on other bioelectric impedance devices but counter to everything my doctor told me at my last physical.
From The Verge
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
