Talk:Torricelli's law/Archive 1

German

I'm not into Wiki code, I found there is a German, complete version of this page at http://de.wikipedia.org/wiki/Torricellis_Theorem which is still unlinked here. 129.132.208.48 10:36, 5 October 2007 (UTC)

This is not strictly true. The rate at which a tank drains is proportional to its discharge coefficient. the discharge coefficient is the ratio of the true drain rate to the max possible (as given by Torricelli's law). the discharge coefficient is a function of the Reynold's number of the fluid. —Preceding unsigned comment added by Skimaniac (talk • contribs) 21:25, 30 March 2008 (UTC)

Comments

Doing some quick calculations, although it is true that the velocity will increase and that the lowest jet will have the greatest velocity, it does not appear to be true that it will travel the furthest distance. (Think, that as you make the lowest hole at the base of the can, it will travel a distance of zero before hitting the ground). Doing some quick calculations, ignoring air resistance and assuming Torricelli's law, it can be shown that at any instant in time, the hole which is halfway between the ground and the top of the water will travel the greatest distance. The picture, as presented, is quite misleading in this regard. --142.161.78.100 (talk) 05:16, 10 April 2010 (UTC)

I'm sorry that I'm not going to do any mathematics to back this up (and I know Wikipedia can't use references to itself (like any good ref material)) but I'm requesting this page be unlinked-up for at least 6 months, as right now, for me, with a wary birgin little watchlist, will have much more trouble finding it when I'm over-my-head in creativity.

You see, I have some novels to write: these issues will be addressed there, just as soon as I can find my graph paper. — Preceding unsigned comment added by Darion29 (talk • contribs) 16:35, 4 July 2011 (UTC)

Wrong picture

The picture is wrong! — Preceding unsigned comment added by 158.195.204.218 (talk) 23:50, 27 May 2012 (UTC)

Please elaborate on what is wrong with the photo. Is this image more accurate? WTF? (talk) 15:12, 4 June 2013 (UTC)

Yes, the picture is wrong, it should like [1] because the lowest jet, although more powerful reaches a shorter distance (at first). Christian.Mercat (talk) 15:08, 6 December 2013 (UTC)

The picture is wrong in a way that Torricelli would be sensitive to: The collection of parabolas has an envelope (an idea discovered by Torricelli) which in this case is a line at 45 degrees from the edge of the water's surface. So all of the parabolic jets shown should be tangent to this line. For each parabola, the point of tangency is at twice the depth (below the surface) of the hole (as correctly stated above by 142.161.78.100, since a jet is farther than all others exactly when it is tangent to the envelope). If this could be fixed while keeping the aesthetically nice stye of the current figure, that would be great. Matt Cook (talk) 12:59, 10 December 2015 (UTC)

Looking at illustrations on the web, this one is the only one I found that gets the envelope right. (Even the other illustration from that same site is wrong.) Some photographs of real teaching experiments show the envelope, sort of, if the spouts are really open vertically aligned holes in the side of the container, but also in real demonstrations the jets often hit and interfere with each other. In general, two jets meet at a depth (below the surface) equal to the sum of the depths of the holes. Matt Cook (talk) 15:37, 10 December 2015 (UTC)

Ok, I improved the picture and listed its basic geometric properties in the caption. Matt Cook (talk) 07:05, 18 December 2015 (UTC)

Derivation is incomplete

The terms Pa, P, y1 and y2 are not defined: they just appear out of nowhere. — Preceding unsigned comment added by Zoetropo (talk • contribs) 04:11, 12 February 2020 (UTC)

I rewrote the derivation; feel free to point out any mistakes or changes that need to be made. Thtatithticth (talk) 06:16, 12 February 2020 (UTC)