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Re: dielectric constant and measuring capacitance



Anyone know how a Wavetek capacitance meter works?
What frequency is being used?

I set up apparatus yesterday to demonstrate the high dielectric
capacity of water. The setup can be seen at
http://www.sfu.ca/physics/people/faculty/palmer/cap1.jpg. Steer
around the picture to see detail (it's big). I will refine the
apparatus and replace the picture later. The resolution is good
enough that you would be able to see all the details - if I had
positioned the apparatus sufficiently well to make them visible.
I know that is a large picture, but I thought it useful to
leave it that way so you could look around.

What I've done is to take two beakers with different diameters
to make a Leyden jar with a cylindrical annulus. It can be
filled easily with water. The little straws are there to center
the inner beaker (which has no beak) within the outer. The
balloon is there to hold the inner electrode foil tightly to
the wall of the beaker, and the big straw is there to allow me
to inflate the balloon within the inner beaker. (In v.2.0 I'll
remember to grease the straw before I tie off the balloon.)

No details yet; there's lots to change. I use a Wimshurst with
its internal Leyden jars disconnected. The discharge spark is
noticeably fatter with water in, but not spectacularly so. I
put the aforementioned Wavetek meter on it. but I have no
illusion that it measures DC capacitance.

Leigh