Feed the hose into the source tank and put your secondary container on the ground. You can do this with your mouth, but this is a bad idea if you're siphoning gas. To avoid air bubbles when sucking out the liquid, hold up your siphon tube vertically—this will give the bubbles a place to escape. If you want to skip sucking altogether, submerge the entire hose in the source tank, then place your thumb firmly over the delivery end. While holding the delivery end of the hose closed, move it to the receiving vessel.
Alex Richert and P. Binder, University of Hawaii at Hilo. The Physics Teacher, Vol. Reverse siphon? Vittorio Zonca's mill. From Dircks The chain model treats the siphon flow as due to different weights of liquid in the two siphon arms. If it were the weight in the arms of the U-tube that causes and sustains liquid flow, then this hypothetical reverse siphon Fig. In fact this ought to allow a siphon to raise liquid from lower to higher levels.
Vittorio Zonca , In his folio Novo Teatro di Machine et Edificii Padua, even proposed this idea as if it could be a useful device to lift water to drive the waterwheel or turbine of a mill.
Of course it could never work. In fact, this overbalanced siphon flows from left to right, from higher to lower level, just as an ordinary siphon does. The self-flowing flask of Robert Boyle. This is a digression, which the reader may skip.
His clever example was a "self-flowing" flask Fig. Why doesn't the greater weight of liquid in the flask force liquid to a higher level in the narrow tube so that it spills over and flows back into the flask.
Perpetual motion! Add a small waterwheel just below the outlet and you could extract energy from the fluid flow. If there were any flow. Boyle's "self-flowing flask". The Hydrostatic Paradox. Even today there are people who see this picture of the flask and can't imagine why it doesn't work.
College students are often puzzled by it and at a loss to explain its fallacy. Zonca can be forgiven, for he lived at a time before the concept of force was well understood, and long before vector analysis of forces became a standard tool for analyzing physical systems. Today's physics students have no such excuse. To make the story short, the misconception here is to suppose that the entire weight of the liquid in the flask must be supported by the smaller weight of liquid in the tube.
This seems impossible, so one imagines the liquid must flow from left to right. But the weight of liquid is partly supported by the sloping walls of the flask. The wall exerts forces normal perpendicular to the wall, and these have upward components.
The liquid in the flask is not entirely supported by weight of liquid on the right, but largely by the flask walls. Overlooking that fact leads to the apparent paradox. The French mathematician Blaise Pascal illustrated it with a demonstration device, Pascal's Vases, which had glass flasks of various shapes and orientations connected to a common water reservoir.
The water level in each flask, whatever the flask's shape, was at the same height. Of course this is the essence of Aristotle's principle that "Water seeks its own level. Pascal's vases left. Join the Discussion. Michael T Apr 4, Apr 16, Thanks for sharing, Michael T.
Michael T Mar 10, The perfect siphon hose would have a control valve at the crest. This is made possible by adding anti-backflow check valves to the inlet and outlet to allow the liquid to flow in the direction to the outlet while preventing air from entering and breaking the siphon when the shutoff valve is closed.
Once the siphon is initially primed, the system will stay primed if air is not allowed to enter at the inlet. Andreas Jan 29, Michael Feb 7, The perfect controllable siphon hose would have a foot check valve at it's inlet and a shutoff valve at it's crest and an anti-backflow valve at it's outlet.
Once this siphon is filled and primed, it would work automatically by opening and closing the shutoff valve. The hose would stay primed as long as air was not allowed to enter the line. Feb 8, Michael Taylor Aug 8, Siphon's can run perpetually using only their own power. The only true perpetual motion machine that continually causes mechanical motion is a Siphon with a Metering Chamber and US Patent discloses this in figure number four of the art.
Timing and the weight of the water allows for a continuous water flow above the source. Aug 13, Thanks for sharing, Michael! This was very interesting! Could you maybe do a wonder about computer code? I would find that even more interesting. Nov 15, Caleb Jan 5, That experiment is cool, is it safe to do without my parents? Jan 6, Dec 16, Jace Nov 24, Nov 26, Jace Nov 30, Dec 2, Related Wonders for You to Explore These methods were then repeated for each of the U-tube and vacuum siphon experiments with dye added to the water.
Attached at either end of the tube were two stainless steel vacuum taps. Priming of the tube was achieved by placing the closed end of the evacuated tube into the degassed water, which was then opened allowing the water to flow up the tube, while the other end remained open to the vacuum system.
Care was taken to prevent the capping oil from entering the tube during this process. Once the tube was entirely filled with degassed water, both ends of the tube were closed ready for the siphon to be set into position.
Before setting the tube in position the siphon was first inverted so that the ends of the tube were at the highest point with the bend at the lowest.
This was done to allow additional degassed water to be added as the increased weight caused a slight expansion in the length of the tube. Once the extra water was added the tube was re-inverted with the bend at the apex and the legs hanging straight down into the reservoirs. Taps at both ends of the tube were then opened so that the liquid could flow freely over the Once the upper reservoir was nearly depleted of liquid, the end was lifted out of the liquid allowing air to flow into the base of the tube.
Throughout the siphoning process no bubbles were observed in the tube, however small bubbles were observed to emanate from the lower end of the siphon during in the final stages of draining the tube. These bubbles were thought to come from air trapped in the tap and the glass vessel at the base of the tube, which became dislodged by the fast flowing liquid.
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