1322 questions and answers in this section
Explain why are some stars called white dwarfs?

Explain why are some stars called white dwarfs?

Historically, the term white dwarf dates back to the early 20th century, when astronomers discovered very small but very bright stars of white color. They...

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Explain why limestone caves often have underground rivers.

Explain why limestone caves often have underground rivers.

Limestone is a sedimentary rock primarily composed of calcium carbonate, often derived from the remains of dead marine organisms accumulated on the sea floor a...

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Explain why pasteurized milk lasts longer than raw milk.

Explain why pasteurized milk lasts longer than raw milk.

Pasteurization is a simple thermal treatment that allows, by rapidly heating milk to a temperature generally between 72°C and 85°C for a few seconds, to...

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Explain why pens sometimes leak in pockets when it is hot?

Explain why pens sometimes leak in pockets when it is hot?

When it is hot, the pen's ink becomes less viscous: in other words, it becomes more fluid and thus more liquid. As it fluidifies, the...

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Explain why do heatwaves affect electricity?

Explain why do heatwaves affect electricity?

Heatwaves often create imbalances in the electrical grid. When electricity demand surges due to intensive use of air conditioning, the grid is put under significant...

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Explain why it is said that the weather is heavy before a summer thunderstorm?

Explain why it is said that the weather is "heavy" before a summer thunderstorm?

That somewhat oppressive sensation of heaviness before a storm mainly comes from the hot, humid, and still air surrounding us. In fact, our body regulates...

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Explain why we blow on hot soup to cool it down?

Explain why we blow on hot soup to cool it down?

Heat spontaneously flows from a hot medium to a colder one: this is the basic rule of heat transfer. In your hot soup, the fast...

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Explain why we sometimes feel a tingling sensation when we drink soda?

Explain why we sometimes feel a tingling sensation when we drink soda?

Sodas are carbonated drinks because carbon dioxide (CO₂) is injected into them under pressure. This gas is responsible for the small bubbles characteristic of sparkling...

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Explain why are reflections on the surface of water inverted compared to reality?

Explain why are reflections on the surface of water inverted compared to reality?

When you observe a reflection on the water, what you see is the light bouncing off the surface. The principle is simple: each ray of...

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Explain why a new book gives off a particular smell?

Explain why a new book gives off a particular smell?

A new book is a complex assembly of organic and chemical materials. The paper used mainly comes from cellulose fibers derived from wood, to which...

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