Thread: Units
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Unread 02-27-2003, 01:18 PM   #5
Since87
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Quote:
Originally posted by gmat

(edit) impedance ? resistance? i'm not sure about the english term here.
electrically: U=RI -> R is the 'resistance' (in French), does that translate as an impedance ?
In French 'impedance' is the complex value of 'resistance', called Z and is Z=a+ib (complex number)
The convention here (at least in electrical engineering) is to use thermal resistance with units of C/W.

The extremely curious can see an example in the lower left corner of page 6 of this component datasheet.

"Impedance" is technically reserved for circuits which are at least partially 'reactive'. (i.e. complex, or purely imaginary)

In actual conversation between EE's "Impedance" is frequently used somewhat sloppily, and is often used to refer to purely resistive circuits.
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