1290 questions and answers in this section
Explain why can sand grains sing?

Explain why can sand grains "sing"?

The sand grains capable of "singing" share common physical characteristics: they are generally round, well-sorted in size, and their surface is particularly smooth and polished, as if...

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Explain why do Norwegian fjords have such steep walls?

Explain why do Norwegian fjords have such steep walls?

Norwegian fjords owe their spectacular appearance to a rather tumultuous geological history. It all begins hundreds of millions of years ago, when tectonic plates collide, pushing and...

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Explain why ancient civilizations often used calendars based on the moon?

Explain why ancient civilizations often used calendars based on the moon?

Ancient civilizations observed the phases of the Moon directly without any special instruments. They simply had to look up and follow its cycle of about...

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Explain why some civilizations worshipped the Sun as a god?

Explain why some civilizations worshipped the Sun as a god?

The Sun has always been perceived as the main source of life by ancient civilizations: simply because without it, there is no heat, no light, and therefore...

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Explain why does the city of Eilat (in Israel) offer coral reefs in the middle of the desert?

Explain why does the city of Eilat (in Israel) offer coral reefs in the middle of the desert?

Nestled between the dry mountains of the Negev Desert and the divinely blue waters of the Red Sea, Eilat is truly unique. Located at the...

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Explain why some mountains emit low noises before an avalanche occurs?

Explain why some mountains emit low noises before an avalanche occurs?

Mountains are in perpetual motion, even if it’s not obvious. At the heart of the rocky massif, the layers of snow and ice accumulated exert...

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Explain why some volcanoes have effusive eruptions while others have explosive eruptions?

Explain why some volcanoes have effusive eruptions while others have explosive eruptions?

Viscosity is basically the ease with which magma flows or doesn't. A very viscous magma, like a paste, struggles to release the gases within it. This creates...

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Explain why do shearwaters travel long distances without getting lost?

Explain why do shearwaters travel long distances without getting lost?

Seabirds have a true internal compass thanks to their sensitivity to the Earth's magnetic field. This natural mechanism acts somewhat like an integrated GPS, intuitively...

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Explain why eggshells are porous.

Explain why eggshells are porous.

If you look closely at an eggshell, you'll quickly notice that it is not as smooth as it appears. Under a microscope, it looks like...

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Explain why do sea anemones close up in the presence of threats?

Explain why do sea anemones close up in the presence of threats?

Sea anemones possess a rudimentary nervous system made up of a network of nerve cells called a diffuse nerve net. When something touches them or...

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