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Re: another version of frequency formula

To: teslaatgrendel.objincdotcom

Subject: Re: another version of frequency formula

From: EDHARRISatMPS.OHIOSTATE.EDU

Date: Tue, 16 Jan 1996 10:39:51 0500 (EST)

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A
>
>The above formula does not take into account the coiling of the wire.
>Written in similar terms to the above, the formula I posted becomes:
>
> c (1/5)
>F =  x (5/4) x (H/D)
> 4 x length of winding
>
>
>c=speed of light
>H=height of coil
>D=diameter of coil
>
>Nothing special. Just highlights the difference due to coiling the wire.
>For an H/D=10, the two forms differ only by a factor of 2.
>
>
>SOrry to beat a dead horse.
>Ed Harris
>
>
>Ed,
The length of wire as measured in what units? Inches, feet, meters ?
Jim Leonard

Jim,
The one nice feature of the above formula is that you can use
whatever units you want as long as they are consistent. For H and D all you
need is the ratio which of course is unitless. If you choose the speed of
light as c=3x10^8 meters/sec, then choose the length of the winding to be
in meters so that the frequency will come out in Hz=1/sec. Alternately, you
could choose the length of the winding in miles and c=186,000 miles/sec and
still get the frequency in Hz.
Eg. as Mark B. reported, his giant coil has the followinf dimensions:
H=11ft
D=4ft
length of winding= "about one mile"
186,000 mile/sec (1/5)
F=  x (5/4) x (11ft/4ft)
4 x 1 mile
F= 71000 Hz
This is close to the self resonant (no top electrode) frequency he
reported (correct me if wrong M).
As I said before, it works well on all the coils I have made as well as all
the coils Malcolm so gernerously reported on.
Ed Harris