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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 does my dog stink when it is wet?

  • Because water washes away their perfume.

  • No.

  • Many microbes like bacteria and fungi live in the fur of a dog.

  • These microbes excrete waste in the form of volatile organic compounds or VOCs.

  • These VOCs are responsible for the stink.

  • Now usually, when the dog is dry, some VOCs evaporate into air.

  • So, the stink or smell is hardly noticeable.

  • However, when the dog plays in water or bathes.

  • The water liberates most of the VOCs from its skin and fur into air

  • Thus making the stink more noticeable.

  • In addition to this, some VOCs even dissolve in water.

  • As this water evaporates, it carries the VOCs with it, thus contributing to the stink.

  • Also, as the water evaporates, it increases the humidity in the air surrounding the dog.

  • Humid air can hold more molecules.

  • So, a higher concentration of VOCs reaches our nose, thus intensifying the stink.

  • Why is glass transparent?

  • Give me minimum 5 years to unravel its mystery.

  • Alright.

  • Now listen.

  • Any substance is said to be transparent.

  • When particles of visible light called photons are not absorbed by the substance.

  • Thus, they easily pass through the substance.

  • However, if the photons get absorbed, then the substance is said to be opaque.

  • But why do some substances absorb photons while others don't?

  • Whether a substance will absorb the photons or not.

  • Depends upon the gaps present in between the orbits of electrons of that substance.

  • If the gaps in a substance are small.

  • Then the electrons of that substance are able to absorb the photons.

  • Which pass through those gaps, making the substance opaque.

  • However, in glass, the gaps are big.

  • Hence, most of the photons do not get absorbed.

  • They easily pass through those gaps, making glass transparent.

  • Is antibacterial soap bad for you?

  • Nope.

  • It is not at all bad.

  • As usual, you are wrong.

  • Antibacterial soaps claim that they destroy or remove more germs or bacteria.

  • As compared to regular soaps.

  • However, this is not completely true.

  • Antibacterial soaps contain various chemicals such as triclosan.

  • Triclocarban that actually don't do any benefit, but instead they harm us.

  • Stop bluffing.

  • Please listen.

  • Long term exposure to triclosan can create antibiotic resistant bacteria or super bacteria.

  • How is that possible?

  • When we use antibacterial soaps that contain triclosan.

  • It may kill most of the bacteria present on our body.

  • But the remaining ones that survived could divide and pass on the resistance to other bacteria.

  • Thus creating super bacteria which are more difficult to kill.

  • Besides this, as triclosan penetrates the skin, it can also cause various health problems.

  • Hence, it is advised to use regular soaps.

  • Topic: Surface tension.

  • Why are drops spherical?

  • Because, personally, I'm fond of spherical shapes as compared to squares.

  • No.

  • It is because of surface tension.

  • Surface tension is the property of liquids.

  • By which surface molecules of a liquid try to hold the liquid together.

  • By acquiring minimum surface area and acting like a stretched membrane.

  • You know what, everything just went over my head.

  • Alright.

  • I'll explain.

  • Inside a drop, each water molecule is pulled with a force by its neighboring molecules.

  • As these forces are equal and opposite, they get neutralized.

  • However, the molecule present at the surface is not attracted outwards.

  • It is attracted only inwards and sideways.

  • Sideways forces get neutralized.

  • But because of the inward force.

  • Each surface molecule contracts to form a shape that has minimum surface area which is a sphere.

  • Topic: Rancidity.

  • Why is a bag of chips half full?

  • Looks like you don't believe me.

  • Open the bag.

  • See I told you.

  • The bag of chips is indeed half full.

  • Why is that so?

  • It is mainly because of a concept called rancidity.

  • When food becomes rancid.

  • It develops an unpleasant smell and taste and it becomes unsafe for consumption.

  • Rancidity generally refers to a condition where the fats and oils present in food get oxidized.

  • Resulting in food spoilage.

  • Since the chips contain fats and oils, they are likely to get rancid.

  • Therefore, to prevent this, nitrogen gas is flushed into bags of chips by manufacturers.

  • But, why nitrogen?

  • Nitrogen does not react with fats and oils.

  • As a result, rancidity does not take place.

  • Moreover, a gas in the bag serves as a cushioning agent and prevents the chips from crumbling.

  • That is why the bag of chips is only filled till half.

It's AumSum Time

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B2 US vocs stink substance bacteria surface antibacterial

Why does my Dog Stink when it is Wet? | #aumsum

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    AumSum posted on 2019/04/13
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