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  • Why do mosquitoes bite only some people?

  • Because they are lazy.

  • No.

  • There are a number of reasons why some people are more prone to mosquito bites.

  • One of them is body odor.

  • Millions of bacteria which live on our skin produce various gases.

  • These gases form our body odor.

  • Some of these body odors attract the mosquitoes.

  • So, this is the reason why mosquitoes prefer me.

  • Besides this, a popular research found that.

  • Mosquitoes tend to bite people with Type O blood nearly twice as often as those with Type A.

  • Exercising can also entice mosquitoes.

  • This is because when we exercise, we release more carbon dioxide, heat, and sweat.

  • Mosquitoes can detect this carbon dioxide and heat.

  • They can also sense various substances in our sweat such as lactic acid.

  • Thus making us more likely to get bitten.

  • Why does hot air balloon float?

  • Because it has invisible wings.

  • No.

  • It is because of density.

  • Density is the measure of mass present per unit volume.

  • Lesser the density, lighter will be the object.

  • Now, density varies with temperature.

  • It is so complicated.

  • All right.

  • I will explain.

  • When a hot air balloon is on ground, the air inside and outside the balloon is of same temperature and density.

  • However, when we turn on the burner of the balloon, the air inside the balloon starts getting hot.

  • The molecules of air move faster and spread apart, taking up more space.

  • Hence, the air inside the balloon becomes less dense than the air outside.

  • As less dense air is lighter, the hot air balloon rises and thus, begins to float.

  • What happens if a plane is struck by lightning?

  • It will start glowing like a disco ball.

  • No.

  • Lightning is a massive flow of charge which carries thousands of volts of electric current.

  • Thus, it is extremely fatal for living beings and can damage anything that comes in its way.

  • Yes.

  • It is really terrifying.

  • Now many times, airplanes get caught in a heavy lightning storm.

  • However, airplanes are designed to handle the lightning strikes.

  • The outer skin of most planes is primarily made of aluminum.

  • Aluminum is a good conductor of electricity.

  • When lightning hits the airplane, the electric current travels through the outer skin of the plane.

  • It does not pass into the plane.

  • Eventually, it exits off through another extremity, such as tail.

  • Thus, the airplane and the passengers within remain protected.

  • Why can't we tickle ourselves?

  • Because we are lazy.

  • No.

  • Areas that are more prone to getting tickled are our vulnerable areas like neck, stomach and armpits.

  • Yes.

  • You are right.

  • Some researchers suggest that laughing on getting tickled by others could be a defense mechanism.

  • It has evolved over the years when touched suddenly in vulnerable areas.

  • This laughter could either be a way to laugh out of a tense situation.

  • To show submission to the person tickling you to stop further tickles.

  • Now, when we tickle ourselves.

  • Our brain is programmed in such a way that it predicts and recognizes our own movements.

  • It knows where our hands can reach.

  • There is no element of surprise or threat, even if touched in vulnerable areas.

  • Hence, we can't tickle ourselves.

  • Why is fluoride added to water?

  • To make water taste like soft drink.

  • No.

  • According to a prevailing study.

  • When fluoride is added to public water supplies.

  • At an average concentration of about 1 part per million or slightly below, it prevents tooth decay.

  • But how?

  • Enamel is the hard outer covering of our tooth.

  • It is primarily made up of hydroxyapatite.

  • Hydroxyapatite is a compound of calcium, phosphorus and hydroxide.

  • Now, when bacteria in our mouth feed on food particles, they produce acid.

  • This acid dissolves the hydroxyapatite leaving behind a residue of calcium and phosphate ions.

  • This results in a tooth decay.

  • Now, when we drink water containing fluoride.

  • The fluoride binds with calcium and phosphate ions forming fluorapatite.

  • As fluorapatite is less susceptible to acid attacks, it helps to stop the tooth decay process.

  • For more educational videos please visit http://www.SmartLearningforAll.com

  • Also, don't forget to subscribe to our YouTube channel.1 00:00:04,500 --> 00:00:06,000 Smart Learning for All

  • Why do mosquitoes bite only some people?

  • Because they are lazy.

  • No.

  • There are a number of reasons why some people are more prone to mosquito bites.

  • One of them is body odor.

  • Millions of bacteria which live on our skin produce various gases.

  • These gases form our body odor.

  • Some of these body odors attract the mosquitoes.

  • So, this is the reason why mosquitoes prefer me.

  • Besides this, a popular research found that.

  • Mosquitoes tend to bite people with Type O blood nearly twice as often as those with Type A.

  • Exercising can also entice mosquitoes.

  • This is because when we exercise, we release more carbon dioxide, heat, and sweat.

  • Mosquitoes can detect this carbon dioxide and heat.

  • They can also sense various substances in our sweat such as lactic acid.

  • Thus making us more likely to get bitten.

  • Why does hot air balloon float?

  • Because it has invisible wings.

  • No.

  • It is because of density.

  • Density is the measure of mass present per unit volume.

  • Lesser the density, lighter will be the object.

  • Now, density varies with temperature.

  • It is so complicated.

  • All right.

  • I will explain.

  • When a hot air balloon is on ground, the air inside and outside the balloon is of same temperature and density.

  • However, when we turn on the burner of the balloon, the air inside the balloon starts getting hot.

  • The molecules of air move faster and spread apart, taking up more space.

  • Hence, the air inside the balloon becomes less dense than the air outside.

  • As less dense air is lighter, the hot air balloon rises and thus, begins to float.

  • What happens if a plane is struck by lightning?

  • It will start glowing like a disco ball.

  • No.

  • Lightning is a massive flow of charge which carries thousands of volts of electric current.

  • Thus, it is extremely fatal for living beings and can damage anything that comes in its way.

  • Yes.

  • It is really terrifying.

  • Now many times, airplanes get caught in a heavy lightning storm.

  • However, airplanes are designed to handle the lightning strikes.

  • The outer skin of most planes is primarily made of aluminum.

  • Aluminum is a good conductor of electricity.

  • When lightning hits the airplane, the electric current travels through the outer skin of the plane.

  • It does not pass into the plane.

  • Eventually, it exits off through another extremity, such as tail.

  • Thus, the airplane and the passengers within remain protected.

  • Why can't we tickle ourselves?

  • Because we are lazy.

  • No.

  • Areas that are more prone to getting tickled are our vulnerable areas like neck, stomach and armpits.

  • Yes.

  • You are right.

  • Some researchers suggest that laughing on getting tickled by others could be a defense mechanism.

  • It has evolved over the years when touched suddenly in vulnerable areas.

  • This laughter could either be a way to laugh out of a tense situation.

  • To show submission to the person tickling you to stop further tickles.

  • Now, when we tickle ourselves.

  • Our brain is programmed in such a way that it predicts and recognizes our own movements.

  • It knows where our hands can reach.

  • There is no element of surprise or threat, even if touched in vulnerable areas.

  • Hence, we can't tickle ourselves.

  • Why is fluoride added to water?

  • To make water taste like soft drink.

  • No.

  • According to a prevailing study.

  • When fluoride is added to public water supplies.

  • At an average concentration of about 1 part per million or slightly below, it prevents tooth decay.

  • But how?

  • Enamel is the hard outer covering of our tooth.

  • It is primarily made up of hydroxyapatite.

  • Hydroxyapatite is a compound of calcium, phosphorus and hydroxide.

  • Now, when bacteria in our mouth feed on food particles, they produce acid.

  • This acid dissolves the hydroxyapatite leaving behind a residue of calcium and phosphate ions.

  • This results in a tooth decay.

  • Now, when we drink water containing fluoride.

  • The fluoride binds with calcium and phosphate ions forming fluorapatite.

  • As fluorapatite is less susceptible to acid attacks, it helps to stop the tooth decay process.

  • For more educational videos please visit http://www.SmartLearningforAll.com

  • Also, don't forget to subscribe to our YouTube channel.

Smart Learning for All

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B2 中高級 美國腔

為什麼蚊子只叮咬一些人? 再加上4個視頻...#aumsum (Why do mosquitoes bite only some people? plus 4 more videos.. #aumsum)

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    AumSum 發佈於 2021 年 01 月 14 日
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