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Date: Sat, 06 Feb 1999
From: Keith Nagel
Subject: Re: PMOD

* There are two ways to fill an ice cube tray. Some
* people like to hold the tray horizontal under the
* faucet, moving it back and forth to fill all the
* individual compartments.

* Other people (like me) like to hold the tray at a
* tilt, letting the water flow in at one end. We like
* to watch the water fill up one section, then spill
* into the next, and then fill the next, etc., until
* the whole tray is full.

* The faucet provides water at a constant rate of
* flow, which propagates a step wave of water, moving
* further and further down the tray.

* The front end of the tray develops a constant
* pressure head (the height of the first
* compartment). The ratio of pressure to flow (V to
* I) at the first compartment is constant).

* This is precisely how the L-C model of a
* transmission line works.

Good analogue for a lumped constant delay line...

An ordinary tube suffices for the distributed model. The hydrodynamic model is an exact analogue of the electrical system.

For example. Charge a tranmssion line to some DC potential. Now put a matched resistor across one end. The line discharges, and the current pulse is twice the electrical length of the line. Why?

Plug one end of a tube, and fill with water. Put your thumb over the open end, and tilt so the tube is horizontal. Remove thumb.

Will the water all come out at once? Or what? Do it and see for yourself. Look closely at the tube, but don't spill water on your shirt 'cause you're so fixated on the tube.

For Further Information:

JLN Labs Home Page

Possibility Of Experimental Study Of Properties Of Time

Torsion Fields

Torsion Field Detectors

Torsion Field Generators For Sale


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