science

Lingqu

Lingqu is a science 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 Lingqu rather than just read about it. In short: The Lingqu (traditional Chinese: 靈渠; simplified Chinese: 灵渠; pinyin: Líng Qú) is a canal in Xing'an County, near Guilin, in the northwestern corner of Guangxi, China. It connects the Xiang River (which flows north into the Yangtze) with the Li River (which flows south into the Gui River and Xijiang, the latter is one of the major tributaries of Pearl River), and thus is part of a historical waterway between the Yang…

Key takeaways

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

Reference excerpt

The Lingqu (traditional Chinese: 靈渠; simplified Chinese: 灵渠; pinyin: Líng Qú) is a canal in Xing'an County, near Guilin, in the northwestern corner of Guangxi, China. It connects the Xiang River (which flows north into the Yangtze) with the Li River (which flows south into the Gui River and Xijiang, the latter is one of the major tributaries of Pearl River), and thus is part of a historical waterway between the Yangtze and the Pearl River Delta. It was the first canal in the world to connect two river valleys and enabled boats to travel 2,000 kilometers (1,200 mi) overland between Northern China and the Pearl River Delta. It is also one of the most well-preserved such projects in the world. The canal is 36.4 kilometers (22.6 mi) long.

History In 214 BC, Qin Shi Huang, the First Emperor of the Qin dynasty (221–206 BC), ordered the construction of a canal connecting the Xiang and the Li rivers, in order to attack the Baiyue tribes in the south. The architect who designed the canal was Shi Lu (Chinese: 史祿). It is the oldest contour canal in the world, receiving its water from the Xiang. It was fitted with thirty-seven flash locks by 825 AD. There is a clear description of pound locks in the twelfth century, which were probably installed one or two centuries before. The canal also aided water conservation by diverting up to a third of the flow of the Xiang to the Li. The canal has been placed on the UNESCO World Heritage Sites tentative list.

Illustrations

Worked examples

Example 1 — a first encounter with Lingqu

Start with the simplest possible case. Write down what Lingqu claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, 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 Lingqu 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 Lingqu 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 Lingqu

In research: Lingqu appears in science 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 Lingqu 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: Lingqu is common in secondary-school and first-year university syllabi. It links to neighbouring topics Canals in China, Chinese history stubs, Chinese inventions, so understanding it makes those chapters shorter.
In everyday life: Look for Lingqu 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.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Lingqu in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Lingqu 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 Lingqu out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Lingqu in simple terms?

Why does Lingqu matter?

Because it connects several science 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 Lingqu?

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 Lingqu.