# Re: mathematics

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Sent: 	Monday, September 08, 1997 5:46 PM
To: 	Tesla List
Subject: 	Re: mathematics

>
> From: 	Kevin[SMTP:wawa-at-spectra-dot-net]
> Sent: 	Sunday, September 07, 1997 8:13 PM
> To: 	Tesla List
> Subject: 	Re: mathematics
>
> Tesla List wrote:
> >
> > From:   DamDeName-at-aol-dot-com[SMTP:DamDeName-at-aol-dot-com]
> > Sent:   Sunday, September 07, 1997 3:10 AM
> > To:     tesla-at-pupman-dot-com
> > Subject:        Re: mathematics
> >
> > Hi Kevin,
> >
> >           One handy-dandy formula for single layer coils is :
> >
> >    L= (N x A)^2 / 9A + 10B
> >
> > where: L   is inductance in microheneries
> >            N   is the number of turns
> >            A   is  the mean radius of the coil in inches
> >            B   is the  length of the coil in inches
> >
> >    The above formula ---- re-arranged as follows --- will determine the
> > number of turns for a given inductance--------------
> >
> >         N = the square root of L(9A  +  10B )/A
> >
> >     According to the scuttlebutt  the above are accurate to 1%
> >
> >
> >
> > Have fun ,
> >                        Sandy
> >
>
> When people are giving the inductance of their chokes as 6mH, does the
> 'm' mean mili or micro?  I assumed it stands for mili, but I don't think
> you can reproduce the symbol for micro with the keyboard.
>
> thanks
> Kevin
>
Kevin, All,

For microhenry use the letter u in lower case as in uH.

rwstephens

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