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I heard on the radio this morning that a jiffy is equal to a power cycle period at 50 or 60 Hz, among other definitions. Completely new to me. Web searches take me to http://www.numericana.com/answer/units.htm#jiffy where it suggests the more modern electrical engineering definition is 10 ms, but with no source given. Before I email Fred Berman, Ph.D., P.E. asking him for his source, I thought I'd ask here. Anyone hear of these definitions, and if so, where?

RE: Jiffy?

Wikipedia simply points back to the website I linked. To be clear, I'm not interested in the many definitions, but those specific to electrical engineering. Also not interested in any http://lmgtfy.com/?q=jiffy types of answers. I'm wondering if there are electricals out there who have actually heard or used the word in this manner. Thanks.

RE: Jiffy?

It's familiar as a colloquial term, generally meaning a fairly short period of time. I have never heard it in any formal, technical context over this side of the pond.

I actually thought Europe had a monopoly on weird names for units of measurement and had used most of them while devising the CGS system, but perhaps this is a late challenge from the colony. smile

If we learn from our mistakes I'm getting a great education!

RE: Jiffy?

good point ! :D  

If there was no electricity there would be no internet. Good point, don´t you? :D

RE: Jiffy?

Never heard the term related one 60 Hz or 50 Hz cycle.  Sounds bogus.  

David Castor

RE: Jiffy?

If "jiffy" works, then where are we with "RCH"?

old field guy

RE: Jiffy?

His 1-cycle suggestion is his opinion.  It's not, as others have said, a definition.

RE: Jiffy?


Below is a link to a little more scientific site at the University of North Carolina-Chapel Hill which has definitions for units of measure. It gives some insight as to where the unit may have come from.


RE: Jiffy?

Let's keep it clean ofg winky smile

(2B)+(2B)'  ?

RE: Jiffy?

IEEE 100 goes from "jerk" to "jitter" in a jiffy.  
(no jiffy there)

(2B)+(2B)'  ?

RE: Jiffy?

10ms?!?  That's incorrect as far as I know.  A jiffy is defined as the time it takes light to transit one foot in a vacuum.  It  happens to be 1.0ns.  This is from an engineering textbook I had in college.

Keith Cress
kcress - http://www.flaminsystems.com

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