1308 questions and answers in this section
Explain why some stars are red giants?

Explain why some stars are "red giants"?

Stars are born from massive clouds of gas and dust called nebulae. Under the influence of gravity, these clouds contract, heat up, and trigger nuclear...

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Explain why ancient pyramids are aligned with certain stars?

Explain why ancient pyramids are aligned with certain stars?

The ancient builders had a perfect understanding of the celestial cycles, carefully observing the stars to track their regular movements and predict significant phenomena. The...

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Explain why radio waves can travel further at night?

Explain why radio waves can travel further at night?

At night, the ionosphere (an electrically charged layer located at high altitude) changes its structure. It becomes more stable and reflects certain radio frequencies better. During the...

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Explain why bats are the only mammals capable of sustained flight?

Explain why bats are the only mammals capable of sustained flight?

The wings of bats are unique: they are made of a flexible skin membrane called patagium, stretched between super long and thin fingers like needles. These extended...

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Explain why light travels slower in water than in air?

Explain why light travels slower in water than in air?

The speed at which light travels directly depends on the refractive index of the medium it passes through. This index, essentially, is like a number...

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Explain why some volcanoes are active while others are dormant?

Explain why some volcanoes are active while others are dormant?

Magma, this burning liquid rock beneath the Earth's surface, largely determines a volcano's ability to erupt. Its texture, called viscosity, directly influences its activity: fluid...

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Explain why indoor plants can help purify the air?

Explain why indoor plants can help purify the air?

Plants capture the carbon dioxide present in the air through their leaves. With sunlight, they use this gas to create their own energy through a...

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Explain why do fish breathe underwater through their gills?

Explain why do fish breathe underwater through their gills?

Fish breathe underwater thanks to their gills, small organs typically located behind the head. The gills function like a kind of oxygen filter: they capture...

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Explain why are some sounds intolerable to human ears?

Explain why are some sounds intolerable to human ears?

In response to certain very unpleasant sounds, the body initially reacts with a contraction reflex of the middle ear muscles, particularly to try to suffer...

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Explain why has the city of Crescent City (in the United States) been affected by so many tsunamis?

Explain why has the city of Crescent City (in the United States) been affected by so many tsunamis?

Crescent City is located on the northwestern coast of California, not far from the border with Oregon, directly across from the Pacific. The big issue...

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