RMS versus AVERGAGE

Hog wash.

To understand Electronics you have to understand Math. Prove it to be mathematically wrong if you're capable ... otherwise go back to your tranquilizers.

Average is zero ... if you don't know that ... then get medical help.

Thumbsun

Pi is an irrational number hence cannot be expressed by a fraction.

Interesting link. Alternatively you can do the integration which gives you the average using numerical methods ... the simplest that comes to my mind is Simpson's rule.

22/7 = 3.1428571428571428571428571428571 comes damn close. Pi = 3.1415926535897932384626433832795

So (22/7)/Pi = 99.959766250584330314720471286155 percent for a

00.0402337494156696852795287139% error.

--
For the last time:  I am not a mad scientist, I'm just a very ticked off
scientist!!!

3.1415926536 Or, essentially 3.141593

22/7 = 3.142 pretty much way the f*ck off, with the first error being in the third place after the decimal. That error location is way too soon for some things, but is just fine for many calculations

Hmm. How about the 999/318 = 3.141509 xxxxx

I can remember that because it's just under 1000 HP from a 318 V8

.Now, lets see if a 318 was ever modified to do that! :)

No, Phil is correct that you are wrong.

The average value of a sine wave over a half cycle is Vp*2/pi (where Vp is the peak value of the sine wave). The average value of a sine wave over a full cycle is zero. The rms value of a sine wave over any number of half waves is Vp/sqrt(2). If you need proof and you understand calculus, most participants of this group can oblige you.

Phil is not known for his tactfulness and I don't know him extremely well, but I suspect he knows much more math than you do. If you are patient and read this newsgroup regularly, you could learn a lot from him. It took me two years to understand how to read Phil's responses and glean the valuable information they contained. Lurk a lot, is my advice.

As I said above, the average of a sine wave is zero over a full cycle. So, I guess the power dissipation in a diode over a full cycle is zero since the current reverses every half cycle? The average over a half cycle is Vp*2/pi (considering half-wave) and that is what the experienced designers on this group would use for the calculation. If you design circuits, it becomes second nature to think of the average as Vp*2/pi (in most cases).

Cheers, John

"John - KD5YI"

** Hmmmm.......

** Two whole years ????

That long - to see the obvious benefit of pithy, common sense ??

** Forget it.

The troll is a stupid, literal thinking, utterly autistic maths wanker.

He is just here " coitusing " with us.

.... Phil

Hardly able to be so described, regardless of correctness level.

Phil said _approximation_. And that most certainly can be expressed as a fraction, just as he said. It looks like you missed the word approximation - or that I, and others, are missing your point. So... what is your point?

Ed

Well, he usually seems to be pithed off.

Cheers

Phil "Not Antipodean" Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058

email: hobbs (atsign) electrooptical (period) net
http://electrooptical.net

That has to be it then.

3 = 3.0... 1 digit (1 kings) 4(8/9)^2 = 3.16... 2 digits (egyptians?) 22/7 = 3.142.... 3 digita (highschool) 355/113 = 3.1415929... 7 digits

cannot be expressed precisely by a fraction.

:) but it's only good to 4 digits.

355/113 is not miraculous in its precision, points like this are common along the continued fraction approximation of a number

--
?? 100% natural

The reason for taking a half cyce is that it gives a good value. Basicly by calculating power is that the current on the negative halve of the sinus is negative too. Negatife multiplied by negative is positive, atleast for an ohms load.

--
pim.

Yes, but I can better remember this value..

But I hate integration...

NT

That works on *so many* levels!

homer