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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.

  • Why is ocean water salty?

  • Several natural processes make ocean water salty.

  • For example, when it rains, the water droplets react with carbon dioxide in the atmosphere Form carbonic acid.

  • Making rainwater slightly acidic.

  • This acidic rainwater reacts with minerals present in the rocks and forms new minerals and salts.

  • These minerals and salts are then carried by flowing water to the oceans, thus making the ocean water salty.

  • In addition to this, along the mid-ocean ridges, magma rises close to the oceanic crust.

  • Here, when the salty ocean water seeps into the earth's crust, it gets hot due to magma.

  • This hot water dissolves more minerals present in the crust and carries them to the oceans.

  • Through fissures called hydrothermal vents, thus making the ocean water salty.

  • Why can we see our breath in the cold?

  • So that we can make weird shapes.

  • No.

  • Our lungs help us to exchange gases.

  • They are always moist and warm.

  • Now when we breathe, we inhale oxygen rich air and exhale carbon dioxide rich air.

  • However, as the lungs are warm and moist, the exhaled air is warm and has more moisture in the form of water vapor.

  • Really.

  • In cold months, when this warm and moist exhaled air comes in contact with the cool air.

  • The moisture in the exhaled air condenses to form tiny water droplets.

  • Thus, we can see these tiny water droplets as cloud or fog in our breath.

  • Do you hear Yanny or Laurel?

  • I hear Yanny.

  • But some people hear Laurel.

  • But why dude?

  • Wait.

  • I'll explain.

  • A sound comprises of several frequencies.

  • However, some people have a greater sensitivity to higher frequencies in a sound.

  • While others have a greater sensitivity to lower frequencies.

  • I have a greater sensitivity towards chocolates.

  • Please listen.

  • In this audio clip, the higher frequency forms the sound Yanny and the lower frequency forms Laurel.

  • So, if you have a greater sensitivity to higher frequencies, then you will probably hear Yanny.

  • Whereas, if you have a greater sensitivity to lower frequencies, then you might hear Laurel.

  • In addition to this, age could also affect the frequencies we hear.

  • This is because as we age, we begin to lose our ability to perceive higher frequencies.

  • Hence, older people tend to hear Laurel, while younger people hear Yanny.

  • What is frostbite?

  • An ice candy.

  • No.

  • Our core body temperature is about 37 degrees Celsius or 98.6 degrees Fahrenheit.

  • To maintain this temperature, our blood transports warmth to all our body.

  • But prolonged exposure to cold temperatures can decrease our core body temperature.

  • Oh no.

  • Now what to do?

  • Now, our brain constricts the blood vessels of our limbs.

  • Diverting blood to the vital organs to maintain their core temperature.

  • As our limbs don't get sufficient warmth, they start to freeze, giving us frostbite.

  • Frostbite progresses in three stages.

  • First is frostnip in which the surface of our skin freezes.

  • During second stage called superficial frostbite, often ice crystals form in the skin.

  • During third stage, i.e., deep frostbite, the underlying tissues, blood vessels, bones, etc.

  • Freeze and may get permanently damaged.

  • Topic: Speed of sound.

  • Why does sound travel faster in summer than in winter?

  • That was an amazing trick.

  • The television switched on immediately after you clapped.

  • Yes.

  • I know.

  • This is one of my favorite tricks.

  • Now, I bet you that the television will not switch on instantly after your clap.

  • This time I'm going to prove you wrong.

  • See.

  • I told you.

  • I lost again.

  • Do you know why the sound took more time to reach the television?

  • This is because the speed of sound decreased.

  • Speed of sound depends on the temperature of the medium.

  • Higher the temperature of the medium, more will be the speed of sound and vice versa.

  • So, in this case, what do you think is the medium?

  • Are you kidding me?

  • I don't know.

  • No Problem.

  • I will tell you.

  • In this case, air is the medium.

  • During summer season, the temperature of air increases.

  • At higher temperature, the molecules of air have more kinetic energy.

  • Hence, they vibrate faster leading to increase in speed of sound.

  • Now, during winter season, the temperature of air decreases.

  • With decrease in temperature, the kinetic energy of the molecules also decreases.

  • Hence, the molecules do not vibrate much.

  • As a result, the speed of sound decreases during winter season.

It's AumSum Time.

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海の水はなぜ塩辛いのか?| 海の水はなぜ塩辛いのか? (Why is Ocean water Salty? | #aumsum)

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    AumSum に公開 2021 年 01 月 14 日
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