1318 questions and answers in this section
Explain why do some crystals change color when exposed to light?

Explain why do some crystals change color when exposed to light?

When light touches a crystal, certain electrons absorb specific colors (certain wavelengths, that is). They capture the light energy and jump to a higher level, entering an...

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Explain why do some trees live for hundreds of years?

Explain why do some trees live for hundreds of years?

To last so long, some trees rely on specialized and constantly active cells, grouped in specific areas called meristems. These meristems regularly renew damaged tissues, much like...

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Explain why oil causes water to sizzle when cooking?

Explain why oil causes water to sizzle when cooking?

Water and oil are two liquids with very different physical properties, which explains why they don't really get along well together in cooking. Water is...

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Explain why a puddle of water evaporates faster in the sun than in the shade?

Explain why a puddle of water evaporates faster in the sun than in the shade?

The sun emits radiation that carries thermal energy. When these rays hit a puddle of water, they increase the agitation of the molecules on the...

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Explain why do schools of fish move in perfect coordination?

Explain why do schools of fish move in perfect coordination?

Fish exchange information through quick visual signals and subtle changes in movement. If one turns sharply, its neighbors immediately pick up on this impulse and...

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Explain why do we get sick more often in winter?

Explain why do we get sick more often in winter?

In winter, several viruses, including those of the flu and the cold, survive longer in cold, dry air, making their spread more efficient. The cool...

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Explain why sand sticks to wet feet at the beach?

Explain why sand sticks to wet feet at the beach?

Water has special properties due to the way its molecules are composed. Each water molecule acts like a tiny magnet, with one side positively charged...

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Explain why is Mount Everest nicknamed the roof of the world?

Explain why is Mount Everest nicknamed the "roof of the world"?

The expression "roof of the world" is not a recent term: it actually comes from the Sanskrit term "Sagarmatha," which roughly means "front (or head)...

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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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