1295 questions and answers in this section
Explain why some glaciers appear blue?

Explain why some glaciers appear blue?

The ice of glaciers is not just simple solid water. It forms through the gradual accumulation of compressed snow, which becomes denser over time. During...

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Explain why time slows down in case of high gravity?

Explain why time slows down in case of high gravity?

According to Einstein and his theory of general relativity, gravity is not simply a force. It actually corresponds to a deformation of space-time caused by...

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Explain why perpetual motion is impossible.

Explain why perpetual motion is impossible.

The rule of the game in the universe is that energy never comes from nowhere and never really disappears. It simply changes from one form...

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Explain why waves are sometimes bioluminescent blue?

Explain why waves are sometimes bioluminescent blue?

Most of the time, it is planktonic microorganisms, especially dinoflagellates, that illuminate the sea. These tiny unicellular algae, like the species Noctiluca scintillans, have the...

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Explain why heavy rains can cause landslides.

Explain why heavy rains can cause landslides.

Landslides occur when a mass of soil, rocks, or mud suddenly rushes down a slope. It starts with a loss of balance of the materials...

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Explain why time seems to pass more slowly at the bottom of a mountain?

Explain why time seems to pass more slowly at the bottom of a mountain?

The human brain is not really a reliable clock: depending on our emotions or experiences, the perceived time changes completely. When we are bored or...

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Explain why some frogs are fluorescent in the dark?

Explain why some frogs are fluorescent in the dark?

In some frogs, nocturnal fluorescence comes from particular molecules located beneath their skin. These compounds absorb ultraviolet (UV) light and then re-emit that energy in...

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Explain why marine mollusks have shells?

Explain why marine mollusks have shells?

About 540 million years ago, during the Cambrian period, the first marine mollusks developed calcium carbonate shells. Initially, these shells primarily served to provide mechanical...

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Explain why electrical cables need to be insulated?

Explain why electrical cables need to be insulated?

An uninsulated electric cable is like a saucepan without a handle: dangerous to touch bare. Good insulation prevents direct contact with live electrical conductors, which...

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Explain why tomatoes grow better with basil?

Explain why tomatoes grow better with basil?

Tomatoes primarily consume nitrogen, while basil likes to draw other minerals like magnesium or calcium. This prevents them from competing for nutrients. As a result, each plant...

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