You can visualize a siphon by thinking of two cups connected by a tube shaped like an upside-down "U. If an experimenter puts one end of the tube into the water-filled cup and sucks the air out of it as you would when using a straw, that will allow the water to flow into the tube. A siphon is created once the water flows up one side of the tube and down the other, into the empty cup. Siphons also work in vacuums, so it doesn't appear that atmospheric pressure is at play, according to a study in the Journal of Chemical Education.
Rather, gravity and molecular cohesion appear to be involved, according to a study in the journal Scientific Reports. Gravity accelerates the water through the "down" part of the tube, into the lower cup. Because water has strong cohesive bonds, these water molecules can pull the water behind them through the uphill portion of the tube, according to Wonderopolis , a site where daily questions get answered.
However, many liquids that do not have strong cohesive bonds still work in siphons, so it's unclear exactly how siphons work in different cases, according to Wonderopolis. What about the paper towel example? This action, called capillary action, allows small volumes of water to flow uphill, against gravity, so long as the water flows through narrow and small spaces.
This upward flow happens when a liquid's adhesion to the walls of a material, such as the paper towel, is stronger than the cohesive forces between its liquid molecules, according to the U. Geological Survey. In plants, water molecules are drawn up capillaries called the xylem, helping the plant to draw in water from the soil, the USGS said. Beneath the continent's ice sit the Gamburtsev Mountains, a massive range with peaks and valleys that are about the same size as the European Alps, she said.
Intriguingly, researchers can tell that the river is flowing backward because the ice on top of it is aligned against the direction of the ice flow, Live Science reported previously. This alignment and the enormous pressure from the ice sheet above it push the water uphill, Bell said. Siphons also work in vacuums, so it doesn't appear that atmospheric pressure is at play, according to a study in the Journal of Chemical Education.
Rather, gravity and molecular cohesion appear to be involved, according to a study in the journal Scientific Reports. Gravity accelerates the water through the "down" part of the tube into the lower cup. Because water has strong cohesive bonds, these water molecules can pull the water behind them through the uphill portion of the tube, according to Wonderopolis , a site where daily questions get answered. However, many liquids that do not have strong cohesive bonds still work in siphons, so it's unclear exactly how siphons work in different cases, Wonderopolis said.
Capillary action What about the paper towel example? This action, called capillary action, allows small volumes of water to flow uphill, against gravity, so long as the water flows through narrow and small spaces. This upward flow happens when a liquid's adhesion to the walls of a material, such as the paper towel, is stronger than the cohesive forces between its liquid molecules, according to the U.
Geological Survey. In plants, water molecules are drawn up capillaries called the xylem, helping the plant to draw in water from the soil, the USGS said. Beneath the continent's ice sits the Gamburtsev Mountains, a massive range with peaks and valleys that are about the same size as the European Alps, she said.
Intriguingly, researchers can tell that the river is flowing backward because the ice on top of it is aligned against the direction of the ice flow, Live Science reported previously. This alignment and the enormous pressure from the ice sheet above it push the water uphill, Bell said. There are other instances in which water has naturally run uphill.
For instance, an 8. In addition, a study in the journal Physical Review Letters showed that small amounts of water put on a hot surface — a scalding pan for instance — can "climb" tiny stairs made out of vapor if the water is hot enough, Live Science reported.
Original article on Live Science. What If the World Stopped Turning?
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