Fw: URGENT! Authenticity of dial on ebay.

Please forgive if this is a repost.  My ISP's mailserver has been down the last two days.     -Original Message-From: Charles Gann <[EMAIL PROTECTED]>To: sundial@rrz.uni-koeln.de Date: Thursday, July 15, 1999 3:44Subject: URGENT! Authenticity of dial on eba

Re: Water Bucket

Hi All, I think David has it right. When I put a hose into my swimming pool (a very large bucket) the effect is barely noticable - probably caused only by local eddies. When it is put into a small bucket with the same nozzle it becomes pronounced. With no nozzle the effect is *greatly* dimi

Re: Water Bucket

Message text written by Tony Moss >BUT as soon as the veriest tip of the nozzle touches the surface of the water it is 'snatched' downwards.< I wonder if there is a surface tension/capillary type effect happening here (probably not)... -- or perhaps the effect is most pronounced near the su

Re: Water Bucket

Hi, How about this - The jet rushing in to the water creates a 'hole'. This hole is caused by the fact that water is pushed down and away in the direction of the jet. is flowing. The water in the bucket rushes in to fill the hole - a vacuum has been created by the fact that water is being

Re: Water Bucket

Wonderful story, Tony! Often, the "obvious" theoretical explanation is just shy of the mark... > So much for theory! :-) > > I'm reminded of making toy paddle boats with children of the sort where a > rectangular notch is cut at the back of a plywood 'boat' and a cruciform > paddle is driven

Re: Water Bucket

Dear All, I'm afraid I've only just got back from a short holiday and so am a bit late in tossing my two penn'orth into the fountain... I'm actually studying a solids and fluids course with the Open University at the moment and have just finished the fluids part (2 assignments due in next week),

Re: a dialist's paradise

Hello Pam: On my map, Guam is very near lat. 145 E. The center of this time zone is 142.5, so a sundial on Guam would have a longitude correction of : 145 - 142.5 = 2.5 deg. , 2.5 X 4 = 10 min. If this quick calculation is right, then Guam doesn't qualify, unless you had a floating sundial near

CD diffraction sundials

Dear friends, some months ago I had announced to Sundial List the pubblication on "Astronomia", organ of the Unione Astrofili Italiani, of an article on the construction of sundials using the diffraction produced on the surface of a CD from the rays of the solar light. The article has not been ye

jet boats & other sundial-related stuff

I had a spare moment at work so I looked up jet boats in Mark's Standard Handbook for Mechanical Engineers. The thrust is m dot *(Vjet - Vboat). This is derived from impulse-momentum which is a sort of rearrangement of the common formula from Sir Isaac, F = m * a to: f = m * dV/dT to: f dT = m *

Re: a dialist's paradise

Arizona is always at GMT -7 hours and has plenty of sun. I'll have to pull out a map and check for specific locations. - Original Message - From: Pam Eastlick <[EMAIL PROTECTED]> To: John Carmichael <[EMAIL PROTECTED]> Cc: Sent: Thursday, July 15, 1999 3:19 PM Subject: Re: a dialist's p

Re: Water Bucket

David Higgon contributed >Tony mentioned that his hose had a jet attachment that fitted onto the >pipe, and I think this is the crucial bit. If typical of such attachments >it will be of a larger diameter than the pipe, probably twice the size, and >increase in diameter in a series of steps, eac