Look up: impedance

1. impedance
   (electronics, physics) Opposition to flow of alternating current. Impedance consists of resistance plus reactance (capacitive or inductive). Measured in Ohms. (2003-12-02)
   Found on http://foldoc.org/impedance
   
   
2. Impedance
   The measure of resistance to alternating current in an electrical circuit. Measured in 'ohms'. An important characteristic in many audio components such as speakers and microphones.
   Found on http://www.encyclo.co.uk/visitor-contrib
   
   
3. Impedance
   A property of all metallic and electrical conductors that describes the total opposition to current flow in an electrical circuit. Resistance, inductance, capacitance and conductance have various influences on the impedance, depending on frequency, dielectric material around conductors, physical rel...
   Found on http://www.zoo.co.uk/~z0001325/Glossary.
   
   
4. Impedance
   1) A term for the electrical resistance found in a/c circuits. Affects the ability of a cable to transmit low level (e.g. sound) signals over a long distance. Measured in Ohms. Speakers are rated according to power handling capabilities (Watts, W) and impedance (Ohms).
   2) The total opposition off...
   Found on http://www.testing1212.co.uk/a.htm
   
   
5. Impedance
   Is the opposition to flow of electrical current made up of resistance (a property of the material at specified temperature), capacitance and inductance.
   Found on http://www.encyclo.co.uk/local/20474
   
   
6. Impedance
   The complex ratio of voltage to current.
   Found on http://www.wavecor.co.uk/gloss.htm
   
   
7. Impedance
   A measure of the AC (alternating current) resistance to the flow of electrical or acoustic energy. In electronics it is measured in Ohms
   Found on http://www.musiconmypc.co.uk/art_glossar
   
   
8. Impedance
   At it most general electronic level, impedance is the amount of resistance and / or reactance offered by an electronic circuit or device to the (AC) current which flows through it. It is commonly represented by the mathematical symbol 'Z', and is measured in Ohms. Some people may have had an unwelco...
   Found on http://www.traditionalmusic.co.uk/music%
   
   
9. Impedance
   Acoustic ImpedanceThe total reaction of a medium to the transmission of sound through it, expressed as the ratio of sound pressure to particle velocity at a given point in the medium. The acoustic impedance Z is useful in describing the acoustic radiation from sources such as surfaces and ducts.Mech...
   Found on http://www.diracdelta.co.uk/science/sour
   
   
10. Impedance
    total opposition to flow of current, measured in ohms; combined effort of resistance, inductance, and capacitance.
    Found on http://www.chemicalglossary.net/definiti
    
    
11. Impedance
    Total effective resistance
    Found on http://www.electricfence-online.co.uk/is
    
    
12. Impedance
    A measure of the total opposition to the flow of alternating current (A.C.) round a circuit; a complex combination of ohmic resistance and reactance.
    Found on http://www.mhs.ox.ac.uk/marconi/collecti
    
    
13. Impedance
    A measure of the response of an electric circuit to an electric current. The actual value is frequency dependent. The current is opposed by the capacitance, inductance and resistance of the circuit.
    Found on http://www.mpoweruk.com/glossary.htm
    
    
14. Impedance
    The total opposition to electrical flow (resistive plus reactive).
    Found on http://www.flowmeterdirectory.com/flowme
    
    
15. impedance
    once the fluid is in the ground it must emerge in one or other of the boreholes with the minimum loss of flow and the minimum head loss in the system; the impedance being defined as head loss divided by return well flow Category: Electrical engineering and energy • the apparent oppositio...
    Found on http://www.mijnwoordenboek.nl/definition
    
    
16. Impedance
    The opposition to the flow of alternating or varying current. Measured in Ohms.
    Found on http://www.encyclo.co.uk/local/20957
    
    
17. Impedance
    Im·ped'ance noun [ Impede + -ance .] (Electricity) The apparent resistance in an electric circuit to the flow of an alternating current, analogous to the actual electrical resistance to a direct current, being the ratio of electromot...
    Found on http://www.encyclo.co.uk/webster/I/17
    
    
18. impedance
    1. Total opposition to flow. When flow is steady, impedance is simply the resistance, e.g., the driving pressure per unit flow; when flow is changing, impedance also includes the factors that oppose changes in flow. Thus, deviations of impedance, from simple ohmic resistance because of the effects o...
    Found on http://www.mondofacto.com/facts/dictiona
    
    
19. impedance
    (im-pēd´әns) obstruction or opposition to passage or flow, as of an electric current or other form of energy. the resistance in alternating current circuits, represented by the letter Z in mathematical formulas. Medical equipment is often rated according to impedance to allow for optimum perform...
    Found on http://www.encyclo.co.uk/local/21001
    
    
20. Impedance
    • (n.) The apparent resistance in an electric circuit to the flow of an alternating current, analogous to the actual electrical resistance to a direct current, being the ratio of electromotive force to the current. It is equal to R2 + X2, where R = ohmic resistance, X = reactance. For an induct...
    Found on http://thinkexist.com/dictionary/meaning
    
    
21. impedance
    impedance 1. Something that delays or prevents progress, or the preventing of progress. 2. Electricity opposition to flow of alternating current; the opposition in an electrical circuit to the flow of alternating current, consisting of resistance and reactance. 3. The ratio of the pressure to the v...
    Found on http://www.wordinfo.info/words/index/inf
    
    
22. Impedance
    Opposition of a circuit to an alternating current, equal to the complex ratio of the voltage to the current in complex notation. The equivalent of resistance in a DC circuit.
    Found on http://www-bdnew.fnal.gov/operations/acc
    
    
23. Impedance
    1) The total opposing force to the flow of current in an ac circuit. 2) The total resistance to flow of an alternating current generally expressed in ohms. It is a combination of resistance and reactance.
    Found on http://www.youngco.com/young2.asp?ID=4&T
    
    
24. Impedance
    A measure of the impediment to the flow of alternating current, measured in ohms at a given frequency. Larger numbers mean higher resistance to current flow.
    Found on http://www.encyclo.co.uk/local/21058
    
    
25. Impedance
    Apparent resistance to flow of electrical current; sometimes used to detect bacterial growth in liquid culture because impedance decreases.
    Found on http://www.dyerlabs.com/glossary/microbi