problem with a conversion (mA and microA)

[mightyc]

Hi. I found this forum while reading the online text book at learningelectronics.net. Very neat.

I've got a math problem that's been driving me nuts for a week now. Is the following correct?
9V/10kOhms = .9mA (wouldn't it be 900microAmps? or is it the same thing?)
or 9/10000=.0009 (4th digit to the right of the decimal is micro territory)
location: Simple parallel circuits : SERIES AND PARALLEL CIRCUITS

The reason I ask is because of a similar equation on the previous page:
9V/18kOhms= 500microAmps
or 9/18000=.0005 (again 4th digit to the right of the decimal is micro..so this one seems correct)
location: Simple series circuits : SERIES AND PARALLEL CIRCUITS

I'm new at all this so maybe I'm just not understanding the conversions correctly.

Any help appreciated,
Thanks!

 

[Nigel Goodwin]

Nothing to do with electronics, it's VERY basic maths.

Milli is ten to the minus 3, and micro is ten to the minus 6.

 

[kpatz]

Milli (m) = 1/1000 or .001. Micro (µ) = 1/1000000 or .000001, or 1/1000th of a milli.

If you divide by kilo you get milli. So 9V/10K = .9 mA or 900 µA.
Divide by mega you get micro. So 9V/1M = 9µA.