Placeholder Image

字幕列表 影片播放

  • It's AumSum Time.

  • Can you guess the title of my next video?

  • Hurry up.

  • Write your guess in the comments section below.

  • Are you afraid of heights?

  • Do you think it is because of vertigo?

  • Vertigo is not necessarily fear of heights.

  • In medical terms, vertigo refers to a false sensation of movement due to which we feel dizzy.

  • The most common type of vertigo is Benign Paroxysmal Positional Vertigo or BPPV.

  • It is caused when our inner ear which helps us maintain balance by detecting motion and position of our body.

  • Doesn't function properly.

  • Normally, when we move our head, the cilia and calcium crystals in our inner ear move.

  • Thus sending signals to the brain about our movement.

  • However, sometimes some crystals dislodge and move into the fluid filled semicircular canals.

  • Now, when we move our head, the crystals move along with the fluid.

  • However, even after our head movement has stopped, the crystals keep moving in the canals.

  • Thus sending wrong signals to the brain that our head is still moving.

  • Due to this wrong information, the person gets a false sensation of movement which makes him feel dizzy.

  • Thus causing vertigo.

  • How do fireflies glow?

  • Using a magic wand.

  • No.

  • Fireflies glow because they produce light by a biochemical reaction.

  • In the lower abdomen of fireflies, there is a chemical called luciferin and an enzyme called luciferase.

  • When oxygen enters into their lower abdomen through tracheal tubes.

  • It basically reacts with luciferin in the presence of luciferase.

  • This reaction produces light.

  • This production and emission of light by a living organism is called bioluminescence.

  • Bioluminescence is a cold light.

  • This means the light produced generates very less heat.

  • Thus, preventing the firefly's abdomen from getting overheated.

  • Yes dude.

  • It is not hot.

  • However, one more interesting fact is that not only adult fireflies but also their eggs and larvae are bioluminescent.

  • Wow.

  • They look so stunning.

  • Why honey doesn't spoil?

  • Coz honey is actually a magical potion.

  • No.

  • Honey doesn't spoil mainly because of osmosis.

  • Osmosis is the movement of water from a region of higher water concentration.

  • Through a semi-permeable membrane to a region of lower water concentration.

  • Now, the water content in honey is far less than the water content in organisms like bacteria and fungi.

  • Hence, when such organisms try to enter honey.

  • The water from their bodies moves out into the honey due to osmosis.

  • As a result, they die and thus, the honey doesn't spoil.

  • In addition to this, some bees produce antibiotics within their bodies to protect themselves against certain bacteria.

  • However, when bees make honey, some of these antibiotics get added to the honey.

  • These antibiotics also prevent the growth of bacteria, thus preventing the honey from spoiling.

  • What is fracking?

  • A dance form.

  • Deep inside the earth, there is a layer of shale rocks.

  • These rocks contain fossil fuels like oil and gas in their pores.

  • To extract these fuels, a technique called fracking or hydraulic fracturing is used.

  • In fracking, a vertical well is drilled into the layer of shale rocks.

  • Then, the drill is turned by 90 degrees and drilling continues horizontally.

  • When the targeted distance is reached, the fracking well is encased.

  • Then, a perforating gun is inserted in the well.

  • When the perforating gun reaches the required distance, the rocks are perforated.

  • Then, the perforating gun is removed and a fracking fluid is pumped in the well.

  • This fluid builds pressure in the perforations, creating cracks in the rocks, thus releasing the fossil fuels.

  • These fuels and the fracking fluid are then drawn to the surface.

  • Topic: Rust.

  • Why is oxalic acid used to remove rust stains?

  • Hey.

  • You have a beautiful antique lamp.

  • But look.

  • It has a rust stain on it.

  • No.

  • Don't clean the rust stain with water.

  • Instead, use this oxalic acid.

  • Oxalic Acid.

  • You just don't want my lamp to be nice and shiny, do you?

  • No, I am helping you.

  • Why don't you listen?

  • Because I know that you are making a fool out of me.

  • Fine.

  • Go ahead.

  • Oh no.

  • See.

  • I had told you.

  • Now will you use the oxalic acid?

  • Look.

  • The stain disappeared.

  • Yes.

  • Do you know how this happened?

  • Wait.

  • Let me tell you.

  • Rust is hydrated iron oxide.

  • It is formed when iron reacts with oxygen and water.

  • Rust is insoluble in water.

  • Hence, it is quite difficult to remove rust stains.

  • So, how does oxalic acid remove the stain?

  • Does it have some supernatural powers?

  • Absolutely not.

  • Oxalic acid reacts with rust to form iron oxalate complex ion.

  • Iron oxalate complex ion is soluble in water.

  • Thus, it can easily be washed away, helping us remove the rust stain.

It's AumSum Time.

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B2 中高級 美國腔

你怕高嗎?| 恐高症|#aumsum (Are you Afraid of Heights? | Vertigo | #aumsum)

  • 27 2
    AumSum 發佈於 2021 年 01 月 14 日
影片單字