# engineering math terminology

#### precaud

Joined Dec 18, 2011
2
Here's an an "engineering math terminology" problem that is stumping me, having to do with parallel complex impedances. Perhaps someone can help.

In the abstract, for multiplication of complex numbers (Z1 * Z2 = Zm), we have factors (Z1, Z2) and product (Zm).

For division of complex numbers (Z1 / Z2 = Zd), we have dividend (Z1), divisor (Z2), and quotient (Zd).

For complex impedances in parallel (Z1 || Z2 = Zp), we have, what?

What is the correct terminology to use to describe each of the operands in this equation? In orher words, how would you complete these sentences:
" Zp is the _________ of Z1 and Z2."
" Z1 and Z2 are _______ of Zp "

Any input is appreciated.

#### Georacer

Joined Nov 25, 2009
5,182
I personally use double slashes (//). This is a very special operation, not usually found in general math, so I don't think there is an operator for it.

I would fill your sentences with "parallel combination" and "the parallel components".

#### Papabravo

Joined Feb 24, 2006
16,775
The parallel combination requires a product, a sum, and a quotient.

Rich (BB code):
Zp = Z1*Z2 / (Z1 + Z2)
In words you could say that Zp is the product divided by the sum.
You could also say that it is the ratio of the product to the sum.

#### precaud

Joined Dec 18, 2011
2
This is a very special operation, not usually found in general math, so I don't think there is an operator for it.
Yes, I've never encountered it outside of electronics. So there is no agreed-upon operator, and no special words assigned to the operands in the equation either.

I would fill your sentences with "parallel combination" and "the parallel components".
That's what I have been using. They're descriptive enough, but a tad awkward if one has to use them repeatedly in a circuit description.