Re: Joules

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Parpp807-at-aol-dot-com>

In a message dated 3/20/02 8:43:58 AM Central Standard Time, tesla-at-pupman-dot-com 
writes:

>  can someone tell me what the formula is  to convert voltage and
>  capacitance to Joules.
>  
Jeff,
In the MKS/SI units:

1 Farad = 1 Coulomb / Volt
1 Volt = 1 Joule/ Coulomb
The Joule is a unit of energy = 1 Newton . meter

Energy = 1/2 CV^2
              = 1/2 x (Coul / V)  (J^2 / Coul^2)
              = 1/2 x (Coul / J / Coul) (J^2 / Coul^2)
Energy  = Joules

Coulombs cancel and J^2 / J = Joules
The Volt is the amount of energy needed 
to move a force of 1 Newton thru a distance
of 1 meter per Coulomb of charge.
Hence: 1 V = 1 J / Coulomb.

Hope that helps.

Ralph Zekelman