Working mechanism of straws and siphon

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What's the difference in the working mechanism between a straw and a siphon? Why do you only need to suck on the siphon once for continuous flow of the liquid whereas if you stop sucking on a straw then liquid stops flowing?
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Is it because for a siphon since the end where the liquid exits is lower than the container level so when the pipe is sucked all the air in the pipe is gone and so liquid moves due to differential pressure, and gravity pulls the liquid down, removing the air in the pipe as the liquid comes down, so this differential pressure is maintained so the liquid just keeps flowing down? Whereas for a straw when you stop sucking on the straw there is no longer a differential pressure to keep the liquid flowing?
 
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Watch this video and answer your own question.

 

FAQ: Working mechanism of straws and siphon

How does a straw work?

A straw works based on the principle of atmospheric pressure. When you suck on a straw, you reduce the air pressure inside the straw. The higher atmospheric pressure outside the straw then pushes the liquid up into the straw and into your mouth.

What is the difference between a straw and a siphon?

A straw relies on suction to move liquid, while a siphon uses gravity and atmospheric pressure to transfer liquid from a higher elevation to a lower elevation. In a siphon, once the liquid starts flowing, it continues to do so without additional suction as long as the outlet is lower than the inlet.

Can a siphon work in a vacuum?

No, a siphon cannot work in a vacuum because it relies on atmospheric pressure to push the liquid through the siphon. Without atmospheric pressure, the liquid would not be pushed into the siphon tube and thus would not flow.

What factors affect the efficiency of a straw?

The efficiency of a straw is affected by factors such as the diameter of the straw, the viscosity of the liquid, the length of the straw, and the strength of the suction applied. A wider diameter allows more liquid to flow, while a longer straw may require more effort to create sufficient suction.

Can a siphon work uphill?

A siphon cannot work uphill over a long distance because it relies on gravity to pull the liquid down to a lower elevation. However, a siphon can temporarily move liquid over a small uphill segment as long as the final outlet is lower than the initial liquid level.

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