# Voltage/Length (fwd)

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From:  John H. Couture [SMTP:couturejh-at-worldnet.att-dot-net]
Sent:  Monday, January 26, 1998 6:19 PM
To:  Tesla List
Subject:  Re: Voltage/Length (fwd)

Antonio -

How do you do the calcs for finding the secondary voltage per Greg Leyh's
problem with 3 MV and 100 pf? Do you use this equation?

Joules = .5 C Vs^2

Many coilers use this equation but do not explain the fact that the
voltage is a transient.

Or do you use this equation?

Vs = Vp sqrt(Cp/Cs)

Note that when the Vp and the Cp/Cs ratio is held constant the Vs voltage
can be changed only by increasing the input wattage and size of the coil.

Do you have any comments on my post regarding power magnification to Jim
Monte per "Magnifying power (was voltage/length)?

John Couture

At 04:42 AM 1/25/98 +0000, you wrote:
>
>----------
>From:  Antonio Carlos M. de Queiroz [SMTP:acmq-at-compuland-dot-com.br]
>Sent:  Friday, January 23, 1998 12:41 PM
>To:  Tesla List
>Subject:  Re: Voltage/Length (fwd)
>
>This physics is rather weird. Power is simply a measure of energy transfer
>per time unit, and before using it you shall say from where and to where the
>energy is going. In a resonant tank there is large power flow between the
>capacitance and the inductance. In a Tesla coil circuit, after a closing of
>the spark gap, there is a large oscillating power flow between the primary
capacitor and
>the primary inductor, that is progressively transformed, as energy is
transferred
>at a smaller power to the secondary by the coupling, into the -same- (or
somewhat
>-less- due to losses) large power flow between the secondary inductor and
the secondary
>capacitor. This is easy to see without calculations, as both circuits oscillate
>at the same frequency, and the maximum energy at the secondary circuit cannot
>be larger than the initial energy in the primary circuit.
>When a spark occurs it quickly discharges the secondary capacitance, and this
>is really done at very large power, with the energy that was in the secondary
>capacitance being dissipated as heat, light, noise, and some irradiation.
>The other point where power amplification can occur is in the energy
transfer from
>the power transformer to the Tesla transformer. But this is simply because
most of the
>energy that was stored in the primary capacitor is transferred to the secondary
>circuit in a few HF cycles after the spark gap closes.
>In conclusion: There is moderate power flow between the power transformer and
>the primary capacitor. There is huge peak power flow between the capacitances
>and inductances in both tanks. There is large power flow between the primary
>tank and the secondary tank.
>No mystery.
>
>Antonio Carlos M. de Queiroz
>mailto:acmq-at-compuland-dot-com.br
>http://www.coe.ufrj.br/~acmq
>
>
>

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