GK : Why Do We Feel Hungry?

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1. Why does the sky appear blue?

Reason: The blue color of the sky is due to the scattering of sunlight by the Earth's atmosphere. Shorter wavelengths, such as blue, are scattered more than longer wavelengths like red, making the sky appear blue.

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2. Why do leaves appear green?

Reason: Leaves contain chlorophyll, which absorbs red and blue light from sunlight but reflects green light, giving leaves their green color.

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3. Why do we feel hungry?

Reason: Hunger is caused by the release of a hormone called ghrelin, which signals the brain to initiate the feeling of hunger when the stomach is empty.

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4. Why do stars twinkle?

Reason: Stars twinkle due to the Earth's atmosphere. The light from stars bends as it passes through layers of air with different temperatures and densities, causing the twinkling effect.

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5. Why do icebergs float on water?

Reason: Icebergs float because ice is less dense than liquid water. The hydrogen bonds in ice form a lattice structure, creating more space between water molecules.

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6. Why does the moon have phases?

Reason: The phases of the moon are caused by its orbit around Earth, changing the portion of the moon illuminated by the sun that is visible from Earth.

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7. Why do we yawn?

Reason: Yawning helps cool down the brain and increase oxygen levels in the blood. It may also be a response to tiredness or boredom to keep alertness levels up.

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8. Why do we need to drink water?

Reason: Water is essential for survival as it regulates body temperature, helps transport nutrients and oxygen, and removes waste products through urination and sweating.

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9. Why does iron rust?

Reason: Iron rusts when it reacts with oxygen and moisture in the air, forming iron oxide (rust) through a chemical reaction called oxidation.

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10. Why do earthquakes occur?

Reason: Earthquakes occur due to the movement of tectonic plates beneath the Earth's surface, which causes a sudden release of energy, creating vibrations known as seismic waves.

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