1308 questions and answers in this section
Explain why does the Earth's rotation slowly slow down over time?

Explain why does the Earth's rotation slowly slow down over time?

The gravitational force between the Earth and the Moon causes tidal forces that slightly deform our planet. This deformation creates ocean "bulges" pointed toward the...

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Explain why some fruits have edible skin while others do not?

Explain why some fruits have edible skin while others do not?

The skin protects the fruit against all kinds of external threats such as bacteria, insects, or even the sun. It also acts as a sort...

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Explain why hot water can dissolve certain minerals more quickly than cold water.

Explain why hot water can dissolve certain minerals more quickly than cold water.

When water heats up, the molecules start to jiggle more. Imagine a crowd: the hotter it gets, the more everyone moves and bumps into each...

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Explain why some trees have bark that appears to peel?

Explain why some trees have bark that appears to "peel"?

Trees, somewhat like human skin, regularly replace the protective outer layer of their trunk. This phenomenon is called exfoliation: it’s what gives the impression that...

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Explain why lakes can change color depending on the season?

Explain why lakes can change color depending on the season?

The color of a lake mainly depends on the elements present in its water and how it reflects light. Pure water absorbs red and lets...

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Explain why do pebbles become round at the bottom of rivers?

Explain why do pebbles become round at the bottom of rivers?

Stones gradually become round due to the action of erosion, a natural phenomenon that wears down and transforms rocks over time. Essentially, several forces come...

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Explain why do birds migrate at such high altitudes?

Explain why do birds migrate at such high altitudes?

Migratory birds generally seek heights where atmospheric conditions become favorable for them. At several hundred or even thousands of meters above the ground, they take...

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Explain why do brick walls tend to crumble over time?

Explain why do brick walls tend to crumble over time?

Bricks are often made from a mixture of clay and water, shaped and then fired at high temperatures. During firing, it becomes hard and solid: this is...

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Explain why do catfish have whiskers?

Explain why do catfish have whiskers?

These funny whiskers, also known as barbels, are actually highly specialized sensory organs in catfish. They are equipped with thousands of small nerve cells that...

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Explain why do the bacteria in our intestines influence our mood?

Explain why do the bacteria in our intestines influence our mood?

Our intestines communicate directly with our brain through an axis called the gut-brain axis. The gut microbiota, consisting of billions of bacteria in our digestive...

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