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  • It's AumSum Time.

  • Can you guess the title of my next video?

  • Hurry up.

  • Write your guess in the comments section below.

  • What is a black hole?

  • Usually, when a star is alive.

  • The inward force of gravity is exactly balanced at each point by the outward force created by hot gases and radiation.

  • These inward and outward forces maintain balance and hold the star together.

  • However, when the star runs out of fuel, there are no hot gases and radiation.

  • Hence, there is no outward force to balance the inward pull of gravity and thus, the star begins to die.

  • The star's core begins to collapse under its own gravity.

  • This collapse causes the outer layers to blow apart in a huge explosion called a supernova.

  • Now, it is estimated that if a star has at least 20 times more mass than our sun.

  • Then the star collapses to form a black hole.

  • The surface or boundary of a black hole is called event horizon.

  • Nothing can escape from within the event horizon of a black hole, not even light.

  • Hence, the black hole appears black.

  • Topic: Human Eyes.

  • What are eye boogers?

  • They are similar to burgers.

  • No.

  • Eye boogers generally contain oil, dust, germs, etc.

  • They are formed from the tear film on our eyes.

  • Does the film have any action scenes?

  • Oh no.

  • The tear film mainly consists of three layers.

  • Mucin layer, aqueous layer and lipid or oily layer.

  • Together, these layers moisturize our eyes.

  • They also trap dust and germs which are removed while blinking.

  • When we blink, the eyelid closes.

  • If there is any dust or germ, it gets discarded along with some tear film through the tear duct into the nasal cavity.

  • But while sleeping, since we don't blink.

  • The tear film, dust and germs get collected in the inner corners of our eyes and start to dry out.

  • Forming eye boogers.

  • How does placebo effect work?

  • I don't know dude.

  • Alright.

  • I'll explain.

  • Placebo in Latin means 'I shall please' and this is what placebos do.

  • Placebos are inactive sugar pills, injections, etc. that look like real medications or treatments.

  • In most cases, they relieve pain and make us feel better, even though they are not actual medicines.

  • This effect of placebos on our body is called the placebo effect.

  • Now, one of the reasons why placebos are effective is that when we take them.

  • Our mind perceives placebos as real medications.

  • Hence, our brain reacts to the placebo in a manner which is similar to when we take real medications.

  • Thus, our brain releases natural painkillers like endorphins that help relieve pain.

  • In addition to this, it also decreases the production of stress hormones, thus making us feel better.

  • Why does airplane food taste bad?

  • I don't know.

  • Wait.

  • I'll explain.

  • Our ability to perceive taste is affected by a few factors such as humidity, air pressure, etc.

  • In an airplane, the humidity is less as compared to that on the ground.

  • This makes the air in the airplane quite dry.

  • Also, to maintain the air pressure inside and outside the airplane, the air pressure inside it is decreased.

  • Decreased air pressure and dry air, dries our nose and mouth.

  • Dry nose cannot properly smell odors.

  • Yes.

  • I'm not abe to smell the burger.

  • Now, smell of food helps us to understand the flavor and ingredients of the food.

  • Thus, the food which we cannot smell properly appears unappealing.

  • Also, dry mouth reduces the sensitivity of our taste buds.

  • As a result, we cannot perceive the taste of food properly.

  • Topic: Respiration.

  • Why should we not overwater potted plants?

  • It's because the water will overflow and make the floor dirty.

  • No.

  • Leaves of a plant take in oxygen from the air present in the atmosphere.

  • While, the roots, being buried in the soil, take in oxygen from the air present in tiny spaces of the soil.

  • When we overwater a potted plant, the air in the tiny spaces gets replaced by water.

  • So, do the roots know how to swim in water?

  • Please listen.

  • As air gets replaced by water, the roots do not get sufficient oxygen to breathe and they begin to rot.

  • This may adversely affect the growth of the plant.

  • Thus, we should always try to supply adequate water to the potted plants and not overwater them.

It's AumSum Time.

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B1 US black hole air placebo hole air pressure star

What is a Black Hole? | #aumsum

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    AumSum posted on 2019/04/10
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