physics

Pouring

Pouring is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Pouring rather than just read about it. In short: Pouring is the act of tilting an open container which has liquid or bulk flowable solid inside of it, to cause the contents to flow out of the container under the influence of gravity. This may be done to move the contents to another container (such as pouring a shared drink from a bottle into individual cups), to coat a surface with the contents (as in pouring a syrup onto solid food, or the artistic technique of p…

Key takeaways

Pouring belongs to physics; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Pouring to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Pouring from memory before moving on to harder problems.

Reference excerpt

Pouring is the act of tilting an open container which has liquid or bulk flowable solid inside of it, to cause the contents to flow out of the container under the influence of gravity. This may be done to move the contents to another container (such as pouring a shared drink from a bottle into individual cups), to coat a surface with the contents (as in pouring a syrup onto solid food, or the artistic technique of paint pouring), or simply to empty the original container.

Physical aspects When a liquid is poured from one container to another, various parameters such as the speed of pouring, the distance between the source and destination containers, vibration, and the rate of heat transfer to or from the environment, may cause changes in the liquid being poured. Depending on context, these changes may be desirable or undesirable. For example, in the preparation of Malaysian-style teh tarik 'pulled tea', the brewed tea mixed with milk is poured back and forth between two containers at an increasing distance in order to create a foam and to cool the tea. In contrast, in industrial processes such as casting where a molten metal is poured into a mould, the pouring process can induce the creation of bifilms (doubly-oxidated surfaces folded over on each other) which lead to further defects in the final cast part. The difficulty of controlling all the variables when pouring purely by hand, along with the potential danger to people in the vicinity from splashing of hot liquid, has led to the development of automated pouring equipment for use in industrial settings. There has also been research in robotics to develop robots which can pour drinks and granular ingredients such as sugar. Systems for pouring face unique difficulties compared to other cases of robots manipulating physical objects: contact sensors cannot be attached directly to liquids, so measuring parameters of pouring, such as vibration and the amount of liquid which has been poured, may require the use of computer vision techniques.

Cultural aspects The metaphor of "pouring prayers" appears in Sanskrit, Latin, and Ancient Greek poetry, in reference to the literal pouring out of a drink onto the ground or over an icon as an offering in a libation.

See also Teapot effect, when a liquid being poured from a container runs down the spout or the body of the vessel instead of flowing out in an arc Decantation, a process for separating a liquid from another liquid or a solid by pouring it into a separate container Bulk material handling

References

Works cited Vanden-Broeck, Jean-Marc; Keller, Joseph B. (1986). "Pouring flows". Phys. Fluids. 29 (12): 3958–3961. Bibcode:1986PhFl...29.3958V. doi:10.1063/1.865735. Davis, Ernest (August 2008). "Pouring liquids: A study in commonsense physical reasoning" (PDF). Artificial Intelligence. 172 (12–13): 1540–1578. doi:10.1016/j.artint.2008.04.003. VanEver, Amanda (2019). The Art of Paint Pouring: Tips, techniques, and step-by-step instructions for creating colorful poured art in acrylic. Walter Foster Publishing. ISBN 9781633227378. Kurke, L. (1989). "Pouring Prayers: A Formula of IE Sacral Poetry". Journal of Indo-European Studies. 17 (1–2): 113–125. Lateiner, Donald (March 2002). "Pouring Bloody Drops (Iliad 16.459): The Grief of Zeus". Colby Quarterly. 38 (1). Campbell, J. (2012). "Stop Pouring, Start Casting". International Journal of Metalcasting. 6 (3): 7–18. doi:10.1007/BF03355529. S2CID 138059264. Li, Long; Wang, Chengjun; Wu, Hongtao (2018). "Research on Kinematics and Pouring Law of a Mobile Heavy Load Pouring Robot". Mathematical Problems in Engineering. 2018: 1–13. doi:10.1155/2018/8790575. Yamaguchi, Akihiko; Atkeson, Christopher G.; Niekum, Scott; Ogasawara, Tsukasa (2014). "Learning pouring skills from demonstration and practice" (PDF). 2014 IEEE-RAS International Conference on Humanoid Robots. pp. 908–915. doi:10.1109/HUMANOIDS.2014.7041472. ISBN 978-1-4799-7174-9. S2CID 740328. Huang, Yongqiang; Wilches, Juan; Sun, Yu (February 2021). "Robot gaining accurate pouring skills through self-supervised learning and generalization". Robotics and Autonomous Systems. 136 103692. arXiv:2011.10150. doi:10.1016/j.robot.2020.103692. Tan, Bonny (2013). "Teh tarik". Singapore: National Library Board. Archived from the original on 2022-12-28. Retrieved 27 October 2023. Schenck, Connor; Fox, Dieter (2017). "Visual closed-loop control for pouring liquids". 2017 IEEE International Conference on Robotics and Automation (ICRA). pp. 2629–2636. arXiv:1610.02610. doi:10.1109/ICRA.2017.7989307. ISBN 978-1-5090-4633-1. S2CID 534730. Zhu, Hairui; Yamakawa, Yuji (2022). "Robotic Pouring Based on Real-Time Observation and Visual Feedback by a High-Speed Vision System". Journal of Robotics and Mechatronics. 34 (5): 965–974. doi:10.20965/jrm.2022.p0965.

Illustrations

Worked examples

Example 1 — a first encounter with Pouring

Start with the simplest possible case. Write down what Pouring claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Pouring before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Pouring ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Pouring

In research: Pouring appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Pouring in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Pouring is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fluid mechanics, so understanding it makes those chapters shorter.
In everyday life: Look for Pouring outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Pouring in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Pouring means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Pouring out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Pouring in simple terms?

Why does Pouring matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Pouring?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Pouring.