science

LEX (sounding rocket)

LEX (sounding rocket) 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 LEX (sounding rocket) rather than just read about it. In short: LEX (French: Lithergol EXpérimentale) was a French experimental hybrid-propellant sounding rocket, developed by ONERA. It had the objective of testing a lithergol fueled rocket engine (an hybrid mixture of solid and liquid propellants - Nylon-metatolueneamine as fuel and mixture of nitric acid and nitrogen tetroxide as oxidizer).

Key takeaways

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

Reference excerpt

LEX (French: Lithergol EXpérimentale) was a French experimental hybrid-propellant sounding rocket, developed by ONERA. It had the objective of testing a lithergol fueled rocket engine (an hybrid mixture of solid and liquid propellants - Nylon-metatolueneamine as fuel and mixture of nitric acid and nitrogen tetroxide as oxidizer). It was the first rocket in history to use this technology, flying 8 times between 1964 and 1967. The rocket had a single stage with a thrust of 10.00 kN (MT.27 hybrid rocket motor), a gross mass of 100 kg, a height of 3.40 m, and a diameter of 0.16 m, reaching an apogee of 115 km.

Launches All LEX launches were carried out from CERES Ile du Levant. The first LEX-01 launch on 25 April 1964 was a partial success, with the payload consisting of a telemetry transmitter. Three LEX-02 rockets were fired on 1 June 1965. One of these rockets, with an initial mass of 78 kg, reached an altitude of 68 km. Four LEX-02-B launches occurred on 1 November 1967. Two were intended as technological tests and two others as actual payload launches. These carried the SECT Meteo meteorological payloads, reaching an altitude of more than 100 km, with a parachute ensuring a correct descent for 31 minutes allowing wind measurements over a wide range of altitudes.

See also Bérénice (rocket) Mélanie (rocket) Veronique (rocket) French space program

References

Illustrations

LEX (sounding rocket): LEX French sounding rocket — LEX French sounding rocket

Worked examples

Example 1 — a first encounter with LEX (sounding rocket)

Start with the simplest possible case. Write down what LEX (sounding rocket) 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 LEX (sounding rocket) 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 LEX (sounding rocket) 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 LEX (sounding rocket)

In research: LEX (sounding rocket) 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 LEX (sounding rocket) 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: LEX (sounding rocket) is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1964 introductions, Hybrid-propellant rockets, Onera sounding rockets, so understanding it makes those chapters shorter.
In everyday life: Look for LEX (sounding rocket) 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “LEX (sounding rocket)” →

Affiliate

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

How to study LEX (sounding rocket) in 20 minutes

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

Frequently asked questions

What is LEX (sounding rocket) in simple terms?

Why does LEX (sounding rocket) 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 LEX (sounding rocket)?

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 LEX (sounding rocket).