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  • It's AumSum Time

  • Hi guys.

  • Can you guess the title of my next video Hurry up.

  • Write your guess in the comments section below.

  • Why are giraffes so tall?

  • Because they pull each other's necks and legs.

  • No.

  • Some scientists believe that being tall helps giraffes feed on leaves which are present at greater heights.

  • As shorter herbivores are not able to reach those heights.

  • It decreases the competition for food.

  • Another study suggests that a giraffe's long neck is evolved to compete or fight for females.

  • Male giraffes whip their neck and swing their heads violently into each other's ribs and neck.

  • This is called necking.

  • The giraffe having longer neck tends to win and hence, is preferred by the female giraffe.

  • A study also suggests that as the legs of giraffes got longer, their necks also gradually got longer.

  • So that they could easily drink water by bending their necks.

  • Some people also think that being tall helps giraffes spot approaching predators.

  • While some others believe that being tall gave them a larger surface area.

  • Thus helping them regulate their body temperature.

  • Why did pirates wear eye patches?

  • To show off.

  • No.

  • When light coming from an object reaches our eyes, it passes through a hole called pupil.

  • When it is too bright, the size of pupil decreases, allowing less light to enter into our eyes.

  • When it is dark, the size of pupil increases, allowing more light to enter into our eyes.

  • Thus helping us see better in dark.

  • However, if we suddenly move from a bright room to a dark room.

  • Our eyes take some time to adapt to the darkness.

  • Hence, a pirate wore an eye patch over a single eye so that, that eye can get adapted to darkness.

  • Now, while fighting in case the pirate had to go under the deck where it is quite dark.

  • He just removed the patch from the covered eye which was already adapted to darkness.

  • Helping the pirate to immediately see in the dark.

  • Why is whale vomit so valuable?

  • Because it contains gold.

  • No.

  • Some scientists suggest that when sperm whales eat animals like squids.

  • They digest most of their body parts.

  • However, their sharp beaks are indigestible which can cause irritation in the digestive tract.

  • Thus, whale's digestive system produces a waxy substance called ambergris.

  • Ambergris covers the sharp beaks helping them to pass through the tract easily.

  • Now, some people thought that whales vomited this ambergris.

  • However, a research suggests that it is expelled from the other end.

  • Then, over time, this ambergris reacts with air, salty water, etc. and hardens to form a waxy rock.

  • This waxy rock or ambergris is used by some perfume companies.

  • But why?

  • This ambergris helps the perfume to stick to our skin, making perfume last longer.

  • Hence, perfume companies pay thousands of dollars for just a pound of ambergris.

  • Topic: Properties of a liquid.

  • Why is a diver able to cut through water in a swimming pool?

  • Simple, because I taught him.

  • No.

  • This is because of intermolecular force.

  • Intermolecular force is the force of attraction present in between the molecules of solids, liquids or gases.

  • Now, the intermolecular forces in liquids are not very strong.

  • This means, I'm the strongest of all.

  • Please listen.

  • Since the intermolecular forces are not strong, the molecules of a liquid are loosely packed.

  • They have empty spaces in between them.

  • As a result, the molecules can be displaced from their original position.

  • Hence, when a diver jumps into water, its molecules get displaced from their original position.

  • The diver is able to cut through the water.

  • Topic: Nuclear fusion.

  • Why is nuclear fusion not used to generate electricity?

  • You really want to know the answer to this, right?

  • But wait.

  • Before answering the question, let us understand what is meant by nuclear fusion.

  • When two lighter nuclei combine to form a heavy nucleus, a large amount of energy is released.

  • This process is called nuclear fusion.

  • Where does this nuclear fusion take place?

  • You think that it takes place in a laboratory?

  • No, you are absolutely wrong.

  • Nuclear fusion takes place in the sun.

  • The nuclei of two hydrogen atoms join together to form a heavy nucleus of helium.

  • With the release of a large amount of energy.

  • How do you think this energy reaches us?

  • No.

  • It does not reach us through power lines.

  • Wait, I will tell you.

  • The energy released after nuclear fusion reaches us in the form of sunlight, ultraviolet radiations, heat, etc.

  • Hey.

  • But we are already producing electricity with the help of nuclear fission.

  • So, why do we require nuclear fusion?

  • For this, you need to first understand the difference between nuclear fusion and nuclear fission.

  • As we already know.

  • Nuclear fusion is the fusion of two lighter nuclei with the release of a large amount of energy.

  • The exact opposite process happens in nuclear fission.

  • Here, a heavier nucleus splits into two lighter nuclei, releasing a large amount of energy.

  • This process of fission is used in nuclear power plants.

  • Where a heavy nucleus of uranium is split into lighter nuclei.

  • The energy that is released in this is used to generate electricity.

  • However, there is a major disadvantage of nuclear fission.

  • Wondering what it is?

  • The major disadvantage is that uranium is a radioactive element.

  • When uranium undergoes fission, it generates radioactive waste along with energy.

  • This radioactive waste is very harmful for most lifeforms and the environment.

  • Hence, we need to find a clean and safe source of energy to generate electricity.

  • What source would that be?

  • Would it be nuclear fusion?

  • You are right.

  • Then why are we not harnessing the energy of nuclear fusion to produce electricity?

  • This is because, for nuclear fusion, two conditions are required.

  • They are high pressure and high temperature.

  • Only when these conditions are met, can the two nuclei travel at very high speeds resulting in collision.

  • On earth, it is extremely difficult to create such high pressure and temperature.

  • Even if we are somehow able to create these conditions, the question is how will we control them?

  • As there are many questions unanswered and unsolved.

  • We have not yet succeeded in using nuclear fusion in the production of electricity.

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長頸鹿為什麼這麼高?| 長頸鹿為什麼這麼高? (Why are Giraffes so Tall? | #aumsum)

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    AumSum 發佈於 2021 年 01 月 14 日
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