Placeholder Image

Subtitles section Play video

  • It's AumSum Time.

  • How do some insects walk on water?

  • They do not walk.

  • They catwalk.

  • No.

  • Water has an unusual property.

  • What is that?

  • Each water molecule is attracted by other molecules around it in all directions.

  • But since the molecules at the surface have no molecules above them.

  • They get attracted inward more strongly.

  • These inward forces of attraction create surface tension.

  • Thus, making the surface act like a stretched membrane.

  • Now, the weight of insects like water strider and fishing spider is very less.

  • So, the force that the insects legs exert on the stretched water surface is lesser.

  • Than the surface tension.

  • Also, as their legs are spread wide apart.

  • Their weight gets further distributed among all the legs.

  • Hence, the insects' legs do not sink.

  • And just create dimples on the stretched water membrane.

  • Helping it walk on water.

  • Nuclear fusion.

  • Why is nuclear fusion not used to generate electricity?

  • You really want to know the answer to this, right?

  • But wait.

  • Before answering the question, let us understand what is meant by nuclear fusion.

  • When two lighter nuclei combine to form a heavy nucleus.

  • A large amount of energy is released.

  • This process is called nuclear fusion.

  • Where does this nuclear fusion take place?

  • You think that it takes place in a laboratory?

  • No, you are absolutely wrong.

  • Nuclear fusion takes place in the sun.

  • The nuclei of two hydrogen atoms join together to form a heavy nucleus of helium.

  • With the release of a large amount of energy.

  • How do you think this energy reaches us?

  • No.

  • It does not reach us through power lines.

  • Wait, I will tell you.

  • The energy released after nuclear fusion reaches us in the form of sunlight.

  • Ultraviolet radiations, heat, etc.

  • Hey.

  • But we are already producing electricity with the help of nuclear fission.

  • So, why do we require nuclear fusion?

  • For this, you need to first understand difference between nuclear fusion and nuclear fission.

  • As we already know, nuclear fusion is the fusion of two lighter nuclei.

  • With the release of a large amount of energy.

  • The exact opposite process happens in nuclear fission.

  • Here, a heavier nucleus splits into two lighter nuclei, releasing a large amount of energy.

  • This process of fission is used in nuclear power plants.

  • Where a heavy nucleus of uranium is split into lighter nuclei.

  • The energy that is released in this is used to generate electricity.

  • However, there is a major disadvantage of nuclear fission.

  • Wondering what it is?

  • The major disadvantage is that uranium is a radioactive element.

  • When uranium undergoes fission, it generates radioactive waste along with energy.

  • This radioactive waste is very harmful for most lifeforms and the environment.

  • Hence, we need to find a clean and safe source of energy to generate electricity.

  • What source would that be?

  • Would it be nuclear fusion?

  • You are right.

  • Then why are we not harnessing the energy of nuclear fusion to produce electricity?

  • This is because, for nuclear fusion, two conditions are required.

  • They are high pressure and high temperature.

  • Only when these conditions are met, can the two nuclei travel at very high speeds.

  • Resulting in collision.

  • On earth, it is extremely difficult to create such high pressure and temperature.

  • Even if we are somehow able to create these conditions.

  • The question is how will we control them?

  • As there are many questions unanswered and unsolved.

  • We have not yet succeeded in using nuclear fusion in the production of electricity.

  • Heat.

  • Why is a laboratory thermometer not used to check body temperature?

  • You have got fever.

  • Why don't you check your body temperature using a thermometer?

  • No.

  • Please do not use a laboratory thermometer.

  • You will not be able to get the correct reading.

  • Why don't you try another one?

  • This is called a clinical thermometer.

  • A clinical thermometer is different from a laboratory thermometer.

  • Seems like you have made your choice.

  • A clinical thermometer has a kink.

  • When we check our body temperature, the kink present in it prevents the mercury.

  • From falling back down, thus helping the thermometer to hold the temperature recorded by it.

  • And giving us an accurate reading.

  • Now, in a laboratory thermometer, this kink is absent.

  • This is because a laboratory thermometer is meant to measures immediate temperature.

  • Hence, after recording our body temperature, until we check it, the mercury will fall.

  • Thus, not giving us an accurate reading.

  • Ultrasound.

  • Why is ultrasound used in sonar?

  • Hey.

  • Looks like you are searching for a treasure hidden in a sunken ship.

  • Why don't you use a sonar?

  • It will emit ultrasounds and help you locate the ship.

  • You know what, I have a better idea.

  • No.

  • A music system will make ordinary sound.

  • So, it is of no use.

  • Do not fool me.

  • I know that the music system is the right choice.

  • See, you are not able to find the ship.

  • Now, will you use a sonar?

  • Look, you easily found the ship.

  • Do you know how a sonar could locate the sunken ship?

  • It was because of ultrasound.

  • Ultrasounds are sounds having very high frequencies which start from 20,000 Hertz.

  • So, is ultrasound used in sonar because of its high frequency?

  • You are absolutely correct.

  • Due to its high frequency, an ultrasound can penetrate to a greater depth.

  • Thus, helping us to locate the depth of the sea, sunken ships, etc.

  • But, I am not able to hear the ultrasound?

  • It is because human beings can hear sound frequencies from 20 Hertz to 20,000 Hertz.

  • As ultrasounds have frequencies higher than 20,000 Hertz, we cannot hear them.

  • Bad conductors of heat.

  • Why are two thin blankets warmer than one thick blanket?

  • Because two chocolates are better than one.

  • No.

  • To understand this, we need to first learn about bad conductors of heat.

  • Bad conductors of heat are the materials which do not allow heat.

  • To easily flow through them.

  • Air, wood and glass are some examples of bad conductors of heat.

  • In these examples, is our train conductor included as well?

  • Just listen.

  • A thick blanket allows much of our body heat to escape into the atmosphere.

  • However, when we use two blankets one on top of the other.

  • Air gets trapped between them.

  • This air being a bad conductor of heat, does not allow our body heat.

  • To easily flow into the atmosphere, thus keeping us warm.

  • Pathogens.

  • Why do we get fever?

  • So that we can take a holiday from work.

  • No.

  • Fever is a protective response of our body to fight against pathogens.

  • Such as bacteria, viruses and fungi.

  • These pathogens cause diseases.

  • Hence, when pathogens enter our body, the immune cells such as white blood cells.

  • Produce chemicals called pyrogens which are released into the bloodstream.

  • I thought like movies, they are released in theaters.

  • Please, pay attention.

  • Hypothalamus, which is a small part of our brain, regulates our body temperature.

  • However, when these pyrogens reach the hypothalamus, it starts to raise our body temperature.

  • Thus, producing fever.

  • Now, one of the reasons for producing this fever is that many pathogens.

  • Cannot survive at high temperatures.

  • Thus, they die and we remain safe.

  • Human tears.

  • Why do onions make you cry?

  • Because they cannot crack a joke.

  • No.

  • Onions consist of amino acid sulfoxides.

  • When we cut an onion, millions of onions cells rupture.

  • Releasing the amino acid sulfoxides along with some special enzymes.

  • These special enzymes react with amino acid sulfoxides.

  • To form a chemical called Syn-propanethial-S-oxide.

  • This chemical is volatile, that is, it easily evaporates at normal temperature.

  • Forming a gas.

  • When this gas reaches our eyes, it reacts with substance that keeps eyes lubricated.

  • And forms mild sulfuric acid.

  • What?

  • An acid in my eyes.

  • Absolutely.

  • This sulfuric acid gives us a burning sensation.

  • Now, in order to wash off this acid, our lacrimal glands produce a disinfecting liquid.

  • But when our eyes cannot hold any extra amount of disinfecting liquid.

  • It starts to fall down, making us cry.

  • Joints.

  • Why do knuckles pop?

  • So that when we get bored we can pop them for time pass.

  • No.

  • A knuckle is a joint in the finger where two bones come together or connect.

  • This joint is filled with a fluid called synovial fluid.

  • Synovial fluid is a viscous fluid containing dissolved gases like oxygen and carbon dioxide.

  • When bones move, the synovial fluid prevents them from grinding against each other.

  • It is so amazing.

  • Indeed.

  • When we stretch or bend our finger, the space between the two bones increases.

  • This causes the synovial fluid to stretch, thus creating low pressure in it.

  • Now, as gases are less soluble at low pressure.

  • The dissolved gases in the synovial fluid undissolve.

  • Resulting in the formation of a bubble, which we hear as the pop sound.

  • Why do animals' eyes glow in the dark?

  • Because they have hidden torches.

  • No.

  • Wait, I will explain.

  • Our eyes have a layer called retina which is made up of photoreceptors.

  • When light enters our eyes, it hits the photoreceptors.

  • Photoreceptors detect light, thus making it possible to see.

  • However, the light which does not hit the photoreceptors remains undetected.

  • Poor undetected light.

  • Now, nocturnal animals like owls, need to see better during the night.

  • Hence, their eyes have another layer below the retina called tapetum lucidum.

  • Now, when light does not hit the photoreceptors, it reaches the tapetum lucidum.

  • This layer acts like a mirror.

  • It reflects light back onto the photoreceptors.

  • Thus, giving them a second chance to detect light.

  • Some of this reflected light also comes out of the animal's eyes.

  • Thus, making it seem that its eyes are glowing.

  • 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 outer skin of the plane.

  • It does not pass into the airplane.

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

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

  • Why cannot dogs eat chocolates?

  • Because I would love to have all the chocolates for myself.

  • Alright.

  • Now listen.

  • Chocolates and other cocoa products contain a toxic component called theobromine.

  • The darker the chocolate, the more theobromine and the more it is harmful.

  • But I eat chocolates and I am completely fine.

  • Our body quickly metabolizes the theobromine.

  • Thus, it is not quite harmful for us.

  • However, dogs process theobromine much more slowly.

  • So, it stays in their bodies for a longer time, resulting in vomiting, diarrhea, etc.

  • Moreover, if large quantities of chocolate are ingested by the dog.

  • Then the effects can be much more severe.

  • The heart rate of dog might beat twice its normal rate, increasing the blood flow.

  • This can prove to be lethal to the dog.

  • What is sleep paralysis?

  • No idea.

  • Sleep paralysis is a condition in which we are conscious.

  • But temporarily unable to move or speak.

  • It can usually occur when we suddenly wake up during REM sleep.

  • What is REM sleep?

  • Basically, there are four stages of sleep.

  • One of them is Rapid eye movement sleep, that is, REM sleep.

  • In this stage, we dream.

  • Researchers suggest that when we enter REM sleep, two chemicals, glycine and GABA.

  • Switch off the activity of cells in the brain that allow our muscles to move.

  • No.

  • This is so bad.

  • No.

  • It is actually beneficial because paralyzed muscles.

  • Prevent us from enacting our dreams in reality and getting hurt.

  • However, sometimes we suddenly wake up during REM sleep.

  • But if glycine and GABA are still active, we are temporarily unable to move.

  • Even though we are conscious.

  • This is called sleep paralysis.

  • Why do newborn babies get jaundice?

  • I do not know.

  • Each red blood cell in our blood lives for about 120 days.

  • Once it gets old, it is broken down into smaller components.

  • One of them is bilirubin.

  • Bilirubin is a yellowish waste compound.

  • Hence, our liver removes the bilirubin from our blood.

  • Which is then excreted by the body through intestines.

  • However, if bilirubin is not removed, its level in the blood starts to rise.

  • And excess bilirubin begins to get deposited in the body tissues.

  • As a result, the skin and white areas of eyes appear yellow, thus causing jaundice.

  • Now, a newborn baby's liver is still developing.

  • Thus, it cannot efficiently remove bilirubin from blood, thus causing it jaundice.

  • Usually, jaundice is normal in babies and will disappear in some days as baby grows.

  • However, if it does not disappear, we should immediately consult a doctor.

  • What is a mirage?

  • An invisible cloak.

  • No.

  • Mirage is an illusion in which it appears as if there is water on ground.

  • On a hot day, the land heats the layers of air closer to it.

  • However, as we move higher, the layers of air get relatively cooler.

  • Thus, the hot lower layers of air near the ground form rarer media.

  • And cold upper layers form denser media.

  • Now, when light coming from sky travels from denser to rarer media.

  • It bends more and more until it exceeds the critical angle.

  • That is, the angle beyond which light gets reflected.

  • This phenomenon is called total internal reflection.

  • When this reflected light reaches our eyes, they trace it backward as a straight line.

  • Hence, the reflection of blue sky appears on the ground.

  • And our brain thinks that there is water, thus causing a mirage.

  • Why do we get eye bags?

  • It is a sign indicating that we need to take a long holiday.

  • No.

  • One of the main reasons for eye bags is aging.

  • As we age, various changes take place in our body.

  • Yes, I get more attractive with age.

  • Now listen.

  • Our skin contains collagen and elastin.

  • They keep our skin firm and elastic.

  • In addition to this, we have fat tissue surrounding our eyes for cushioning.

  • But as we age, our skin produces less collagen and elastin.

  • Causing our skin to become loose.

  • Also, the muscles and ligaments that hold fat tissue in place begin to get loose.

  • And the fat starts dropping down.

  • This loose skin and fat make the area around our eyes appear swollen.

  • Giving us eye bags.

  • Besides this, heredity, salt intake, smoking, etc.

  • May also contribute to formation of eye bags.

  • Is gluten bad for you?

  • Gluten is bad for everybody.

  • As usual, you are wrong.

  • Gluten is a combination of proteins found in grains like wheat, barley and rye.

  • Gluten makes dough sticky and gives pasta its chewiness.

  • Now, gluten is not usually harmful.

  • But people having a digestive disorder called celiac disease should not consume gluten.

  • But why?

  • When people having celiac disease eat gluten, it triggers an autoimmune response.

  • In this response, the immune cells attack our own body tissues.

  • Damaging the villi present in the small intestine.

  • Thus, causing inflammation, diarrhea, fatigue, etc.

  • In addition to this, damaged villi will not be able to absorb the required nutrients.

  • Thus, causing weight loss, iron deficiency, etc.

  • Thus, people suffering from celiac disease.

  • As well as those having gluten related allergies should preferably have a gluten free diet.

  • Why are sunsets red?

  • Because sunsets are romantic.

  • No.

  • It is basically because of scattering of light in the atmosphere.

  • Our atmosphere is primarily composed of tiny nitrogen and oxygen particles.

  • Now usually, when sunlight comprising of seven colors passes through the atmosphere.

  • It hits the nitrogen and oxygen particles.

  • These particles scatter blue and violet light more.

  • As compared to red, orange and other colored lights.

  • Hence, mostly bluish light enters our eyes, thus making the sky to usually appear blue.

  • However, during sunset, the sunlight must pass through a greater distance.

  • In the earth's atmosphere, causing it to pass through more particles.

  • As a result, most of the blue and violet light get scattered before they reach our eyes.

  • Due to this, the less scattered light like red or orange reaches our eyes.

  • Making the sunset appear red.

  • Are Einstein's gravitational waves real?

  • No.

  • They are waves created by Titanic.

  • As always, you are wrong.

  • Gravity is the attractive force with which two objects pull each other.

  • However, Albert Einstein imagined gravity as well as space and time a little differently.

  • His theory of general relativity unified two separate entities space and time.

  • Into a single entity called spacetime.

  • Spacetime can be considered as the fabric of universe.

  • Now, just like a heavy ball creates a curve or distorts the trampoline.

  • Mass of an object creates a curve in spacetime, that is, in the fabric of universe.

  • According to Einstein, this curve is gravity.

  • This trampoline is amazing.

  • First listen.

  • Just like our hands create ripples in water, moving objects create ripples in spacetime.

  • These ripples are termed as gravitational waves.

  • Gravitational waves were directly observed for the first time on September 14, 2015.

  • By Laser Interferometer Gravitational Observatory in the US.

  • Why do we love chocolates?

  • Chocolate is one of the most craved foods in the world.

  • It just melts in our mouth and tastes so good that.

  • Many of us are ready to eat them at any given time.

  • Now, one of the reasons why we love chocolates is because.

  • They contain a substance called anandamide.

  • In Sanskrit, 'Ananda' means 'bliss'.

  • Now, when we eat chocolates, anandamide present in them.

  • Binds to special receptors in the brain.

  • Giving us bliss and joy, thus making us love chocolates.

  • Some chocolates also contain substances like theobromine.

  • It is thought that this theobromine makes our brain produce anandamide by itself.

  • Making sure that we feel blissful after eating chocolates.

  • In addition to this, most types of chocolates contain sugar to make them taste sweet.

  • Sugar activates the reward system in the brain.

  • Due to which neurotransmitters like dopamine are released.

  • Dopamine gives us pleasure and makes us feel good.

  • As it makes us feel good, we tend to eat more chocolates to get the same feeling.

  • And thus, we get addicted to chocolates.

  • Moreover, whether it is milk chocolate, white chocolate or dark chocolate.

  • There are numerous varieties to choose from.

  • Also, there are dry fruits like raisins, almonds, cashew nuts, etc. which we generally like.

  • When these dry fruits are added to chocolates, the desire to eat chocolates increases.

  • Also, according to a study.

  • It is observed that salt suppresses bitterness and increases sweetness.

  • Hence, while preparing desserts like chocolate cakes, cookies, brownies, etc.

  • A little salt is added to them, making the desserts more inviting and tempting.

  • Thus, we easily get attracted towards them.

  • How tall can we grow?

  • I can grow as big as the Eiffel Tower.

  • Stop bluffing.

  • Height is determined by a number of factors.

  • One of them is our genes.

  • We inherit our genes from our parents.

  • Hence, these genes will make us grow approximately as tall as our parents.

  • In addition to this, factors like nutrition, physical health, hormones, etc.

  • Also affect our height.

  • Now, if we grow taller than what we are at present.

  • Then we will not be able to support our body's structure efficiently.

  • For this, we would require much larger bones.

  • Or they need to be made of much stronger material.

  • In addition to this, if we were taller, the amount of blood in our body would be more.

  • Thus, making it hard for the heart to pump so much blood.

  • Besides this, the earth's gravity constantly pulls us down.

  • As a result, it prevents us from getting taller.1 00:00:01,900 --> 00:00:04,740 It's AumSum Time.

  • How do some insects walk on water?

  • They do not walk.

  • They catwalk.

  • No.

  • Water has an unusual property.

  • What is that?

  • Each water molecule is attracted by other molecules around it in all directions.

  • But since the molecules at the surface have no molecules above them.

  • They get attracted inward more strongly.

  • These inward forces of attraction create surface tension.

  • Thus, making the surface act like a stretched membrane.

  • Now, the weight of insects like water strider and fishing spider is very less.

  • So, the force that the insects legs exert on the stretched water surface is lesser.

  • Than the surface tension.

  • Also, as their legs are spread wide apart.

  • Their weight gets further distributed among all the legs.

  • Hence, the insects' legs do not sink.

  • And just create dimples on the stretched water membrane.

  • Helping it walk on water.

  • Nuclear fusion.

  • Why is nuclear fusion not used to generate electricity?

  • You really want to know the answer to this, right?

  • But wait.

  • Before answering the question, let us understand what is meant by nuclear fusion.

  • When two lighter nuclei combine to form a heavy nucleus.

  • A large amount of energy is released.

  • This process is called nuclear fusion.

  • Where does this nuclear fusion take place?

  • You think that it takes place in a laboratory?

  • No, you are absolutely wrong.

  • Nuclear fusion takes place in the sun.

  • The nuclei of two hydrogen atoms join together to form a heavy nucleus of helium.

  • With the release of a large amount of energy.

  • How do you think this energy reaches us?

  • No.

  • It does not reach us through power lines.

  • Wait, I will tell you.

  • The energy released after nuclear fusion reaches us in the form of sunlight.

  • Ultraviolet radiations, heat, etc.

  • Hey.

  • But we are already producing electricity with the help of nuclear fission.

  • So, why do we require nuclear fusion?

  • For this, you need to first understand difference between nuclear fusion and nuclear fission.

  • As we already know, nuclear fusion is the fusion of two lighter nuclei.

  • With the release of a large amount of energy.

  • The exact opposite process happens in nuclear fission.

  • Here, a heavier nucleus splits into two lighter nuclei, releasing a large amount of energy.

  • This process of fission is used in nuclear power plants.

  • Where a heavy nucleus of uranium is split into lighter nuclei.

  • The energy that is released in this is used to generate electricity.

  • However, there is a major disadvantage of nuclear fission.

  • Wondering what it is?

  • The major disadvantage is that uranium is a radioactive element.

  • When uranium undergoes fission, it generates radioactive waste along with energy.

  • This radioactive waste is very harmful for most lifeforms and the environment.

  • Hence, we need to find a clean and safe source of energy to generate electricity.

  • What source would that be?

  • Would it be nuclear fusion?

  • You are right.

  • Then why are we not harnessing the energy of nuclear fusion to produce electricity?

  • This is because, for nuclear fusion, two conditions are required.

  • They are high pressure and high temperature.

  • Only when these conditions are met, can the two nuclei travel at very high speeds.

  • Resulting in collision.

  • On earth, it is extremely difficult to create such high pressure and temperature.

  • Even if we are somehow able to create these conditions.

  • The question is how will we control them?

  • As there are many questions unanswered and unsolved.

  • We have not yet succeeded in using nuclear fusion in the production of electricity.

  • Heat.

  • Why is a laboratory thermometer not used to check body temperature?

  • You have got fever.

  • Why don't you check your body temperature using a thermometer?

  • No.

  • Please do not use a laboratory thermometer.

  • You will not be able to get the correct reading.

  • Why don't you try another one?

  • This is called a clinical thermometer.

  • A clinical thermometer is different from a laboratory thermometer.

  • Seems like you have made your choice.

  • A clinical thermometer has a kink.

  • When we check our body temperature, the kink present in it prevents the mercury.

  • From falling back down, thus helping the thermometer to hold the temperature recorded by it.

  • And giving us an accurate reading.

  • Now, in a laboratory thermometer, this kink is absent.

  • This is because a laboratory thermometer is meant to measures immediate temperature.

  • Hence, after recording our body temperature, until we check it, the mercury will fall.

  • Thus, not giving us an accurate reading.

  • Ultrasound.

  • Why is ultrasound used in sonar?

  • Hey.

  • Looks like you are searching for a treasure hidden in a sunken ship.

  • Why don't you use a sonar?

  • It will emit ultrasounds and help you locate the ship.

  • You know what, I have a better idea.

  • No.

  • A music system will make ordinary sound.

  • So, it is of no use.

  • Do not fool me.

  • I know that the music system is the right choice.

  • See, you are not able to find the ship.

  • Now, will you use a sonar?

  • Look, you easily found the ship.

  • Do you know how a sonar could locate the sunken ship?

  • It was because of ultrasound.

  • Ultrasounds are sounds having very high frequencies which start from 20,000 Hertz.

  • So, is ultrasound used in sonar because of its high frequency?

  • You are absolutely correct.

  • Due to its high frequency, an ultrasound can penetrate to a greater depth.

  • Thus, helping us to locate the depth of the sea, sunken ships, etc.

  • But, I am not able to hear the ultrasound?

  • It is because human beings can hear sound frequencies from 20 Hertz to 20,000 Hertz.

  • As ultrasounds have frequencies higher than 20,000 Hertz, we cannot hear them.

  • Bad conductors of heat.

  • Why are two thin blankets warmer than one thick blanket?

  • Because two chocolates are better than one.

  • No.

  • To understand this, we need to first learn about bad conductors of heat.

  • Bad conductors of heat are the materials which do not allow heat.

  • To easily flow through them.

  • Air, wood and glass are some examples of bad conductors of heat.

  • In these examples, is our train conductor included as well?

  • Just listen.

  • A thick blanket allows much of our body heat to escape into the atmosphere.

  • However, when we use two blankets one on top of the other.

  • Air gets trapped between them.

  • This air being a bad conductor of heat, does not allow our body heat.

  • To easily flow into the atmosphere, thus keeping us warm.

  • Pathogens.

  • Why do we get fever?

  • So that we can take a holiday from work.

  • No.

  • Fever is a protective response of our body to fight against pathogens.

  • Such as bacteria, viruses and fungi.

  • These pathogens cause diseases.

  • Hence, when pathogens enter our body, the immune cells such as white blood cells.

  • Produce chemicals called pyrogens which are released into the bloodstream.

  • I thought like movies, they are released in theaters.

  • Please, pay attention.

  • Hypothalamus, which is a small part of our brain, regulates our body temperature.

  • However, when these pyrogens reach the hypothalamus, it starts to raise our body temperature.

  • Thus, producing fever.

  • Now, one of the reasons for producing this fever is that many pathogens.

  • Cannot survive at high temperatures.

  • Thus, they die and we remain safe.

  • Human tears.

  • Why do onions make you cry?

  • Because they cannot crack a joke.

  • No.

  • Onions consist of amino acid sulfoxides.

  • When we cut an onion, millions of onions cells rupture.

  • Releasing the amino acid sulfoxides along with some special enzymes.

  • These special enzymes react with amino acid sulfoxides.

  • To form a chemical called Syn-propanethial-S-oxide.

  • This chemical is volatile, that is, it easily evaporates at normal temperature.

  • Forming a gas.

  • When this gas reaches our eyes, it reacts with substance that keeps eyes lubricated.

  • And forms mild sulfuric acid.

  • What?

  • An acid in my eyes.

  • Absolutely.

  • This sulfuric acid gives us a burning sensation.

  • Now, in order to wash off this acid, our lacrimal glands produce a disinfecting liquid.

  • But when our eyes cannot hold any extra amount of disinfecting liquid.

  • It starts to fall down, making us cry.

  • Joints.

  • Why do knuckles pop?

  • So that when we get bored we can pop them for time pass.

  • No.

  • A knuckle is a joint in the finger where two bones come together or connect.

  • This joint is filled with a fluid called synovial fluid.

  • Synovial fluid is a viscous fluid containing dissolved gases like oxygen and carbon dioxide.

  • When bones move, the synovial fluid prevents them from grinding against each other.

  • It is so amazing.

  • Indeed.

  • When we stretch or bend our finger, the space between the two bones increases.

  • This causes the synovial fluid to stretch, thus creating low pressure in it.

  • Now, as gases are less soluble at low pressure.

  • The dissolved gases in the synovial fluid undissolve.

  • Resulting in the formation of a bubble, which we hear as the pop sound.

  • Why do animals' eyes glow in the dark?

  • Because they have hidden torches.

  • No.

  • Wait, I will explain.

  • Our eyes have a layer called retina which is made up of photoreceptors.

  • When light enters our eyes, it hits the photoreceptors.

  • Photoreceptors detect light, thus making it possible to see.

  • However, the light which does not hit the photoreceptors remains undetected.

  • Poor undetected light.

  • Now, nocturnal animals like owls, need to see better during the night.

  • Hence, their eyes have another layer below the retina called tapetum lucidum.

  • Now, when light does not hit the photoreceptors, it reaches the tapetum lucidum.

  • This layer acts like a mirror.

  • It reflects light back onto the photoreceptors.

  • Thus, giving them a second chance to detect light.

  • Some of this reflected light also comes out of the animal's eyes.

  • Thus, making it seem that its eyes are glowing.

  • 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 outer skin of the plane.

  • It does not pass into the airplane.

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

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

  • Why cannot dogs eat chocolates?

  • Because I would love to have all the chocolates for myself.

  • Alright.

  • Now listen.

  • Chocolates and other cocoa products contain a toxic component called theobromine.

  • The darker the chocolate, the more theobromine and the more it is harmful.

  • But I eat chocolates and I am completely fine.

  • Our body quickly metabolizes the theobromine.

  • Thus, it is not quite harmful for us.

  • However, dogs process theobromine much more slowly.

  • So, it stays in their bodies for a longer time, resulting in vomiting, diarrhea, etc.

  • Moreover, if large quantities of chocolate are ingested by the dog.

  • Then the effects can be much more severe.

  • The heart rate of dog might beat twice its normal rate, increasing the blood flow.

  • This can prove to be lethal to the dog.

  • What is sleep paralysis?

  • No idea.

  • Sleep paralysis is a condition in which we are conscious.

  • But temporarily unable to move or speak.

  • It can usually occur when we suddenly wake up during REM sleep.

  • What is REM sleep?

  • Basically, there are four stages of sleep.

  • One of them is Rapid eye movement sleep, that is, REM sleep.

  • In this stage, we dream.

  • Researchers suggest that when we enter REM sleep, two chemicals, glycine and GABA.

  • Switch off the activity of cells in the brain that allow our muscles to move.

  • No.

  • This is so bad.

  • No.

  • It is actually beneficial because paralyzed muscles.

  • Prevent us from enacting our dreams in reality and getting hurt.

  • However, sometimes we suddenly wake up during REM sleep.

  • But if glycine and GABA are still active, we are temporarily unable to move.

  • Even though we are conscious.

  • This is called sleep paralysis.

  • Why do newborn babies get jaundice?

  • I do not know.

  • Each red blood cell in our blood lives for about 120 days.

  • Once it gets old, it is broken down into smaller components.

  • One of them is bilirubin.

  • Bilirubin is a yellowish waste compound.

  • Hence, our liver removes the bilirubin from our blood.

  • Which is then excreted by the body through intestines.

  • However, if bilirubin is not removed, its level in the blood starts to rise.

  • And excess bilirubin begins to get deposited in the body tissues.

  • As a result, the skin and white areas of eyes appear yellow, thus causing jaundice.

  • Now, a newborn baby's liver is still developing.

  • Thus, it cannot efficiently remove bilirubin from blood, thus causing it jaundice.

  • Usually, jaundice is normal in babies and will disappear in some days as baby grows.

  • However, if it does not disappear, we should immediately consult a doctor.

  • What is a mirage?

  • An invisible cloak.

  • No.

  • Mirage is an illusion in which it appears as if there is water on ground.

  • On a hot day, the land heats the layers of air closer to it.

  • However, as we move higher, the layers of air get relatively cooler.

  • Thus, the hot lower layers of air near the ground form rarer media.

  • And cold upper layers form denser media.

  • Now, when light coming from sky travels from denser to rarer media.

  • It bends more and more until it exceeds the critical angle.

  • That is, the angle beyond which light gets reflected.

  • This phenomenon is called total internal reflection.

  • When this reflected light reaches our eyes, they trace it backward as a straight line.

  • Hence, the reflection of blue sky appears on the ground.

  • And our brain thinks that there is water, thus causing a mirage.

  • Why do we get eye bags?

  • It is a sign indicating that we need to take a long holiday.

  • No.

  • One of the main reasons for eye bags is aging.

  • As we age, various changes take place in our body.

  • Yes, I get more attractive with age.

  • Now listen.

  • Our skin contains collagen and elastin.

  • They keep our skin firm and elastic.

  • In addition to this, we have fat tissue surrounding our eyes for cushioning.

  • But as we age, our skin produces less collagen and elastin.

  • Causing our skin to become loose.

  • Also, the muscles and ligaments that hold fat tissue in place begin to get loose.

  • And the fat starts dropping down.

  • This loose skin and fat make the area around our eyes appear swollen.

  • Giving us eye bags.

  • Besides this, heredity, salt intake, smoking, etc.

  • May also contribute to formation of eye bags.

  • Is gluten bad for you?

  • Gluten is bad for everybody.

  • As usual, you are wrong.

  • Gluten is a combination of proteins found in grains like wheat, barley and rye.

  • Gluten makes dough sticky and gives pasta its chewiness.

  • Now, gluten is not usually harmful.

  • But people having a digestive disorder called celiac disease should not consume gluten.

  • But why?

  • When people having celiac disease eat gluten, it triggers an autoimmune response.

  • In this response, the immune cells attack our own body tissues.

  • Damaging the villi present in the small intestine.

  • Thus, causing inflammation, diarrhea, fatigue, etc.

  • In addition to this, damaged villi will not be able to absorb the required nutrients.

  • Thus, causing weight loss, iron deficiency, etc.

  • Thus, people suffering from celiac disease.

  • As well as those having gluten related allergies should preferably have a gluten free diet.

  • Why are sunsets red?

  • Because sunsets are romantic.

  • No.

  • It is basically because of scattering of light in the atmosphere.

  • Our atmosphere is primarily composed of tiny nitrogen and oxygen particles.

  • Now usually, when sunlight comprising of seven colors passes through the atmosphere.

  • It hits the nitrogen and oxygen particles.

  • These particles scatter blue and violet light more.

  • As compared to red, orange and other colored lights.

  • Hence, mostly bluish light enters our eyes, thus making the sky to usually appear blue.

  • However, during sunset, the sunlight must pass through a greater distance.

  • In the earth's atmosphere, causing it to pass through more particles.

  • As a result, most of the blue and violet light get scattered before they reach our eyes.

  • Due to this, the less scattered light like red or orange reaches our eyes.

  • Making the sunset appear red.

  • Are Einstein's gravitational waves real?

  • No.

  • They are waves created by Titanic.

  • As always, you are wrong.

  • Gravity is the attractive force with which two objects pull each other.

  • However, Albert Einstein imagined gravity as well as space and time a little differently.

  • His theory of general relativity unified two separate entities space and time.

  • Into a single entity called spacetime.

  • Spacetime can be considered as the fabric of universe.

  • Now, just like a heavy ball creates a curve or distorts the trampoline.

  • Mass of an object creates a curve in spacetime, that is, in the fabric of universe.

  • According to Einstein, this curve is gravity.

  • This trampoline is amazing.

  • First listen.

  • Just like our hands create ripples in water, moving objects create ripples in spacetime.

  • These ripples are termed as gravitational waves.

  • Gravitational waves were directly observed for the first time on September 14, 2015.

  • By Laser Interferometer Gravitational Observatory in the US.

  • Why do we love chocolates?

  • Chocolate is one of the most craved foods in the world.

  • It just melts in our mouth and tastes so good that.

  • Many of us are ready to eat them at any given time.

  • Now, one of the reasons why we love chocolates is because.

  • They contain a substance called anandamide.

  • In Sanskrit, 'Ananda' means 'bliss'.

  • Now, when we eat chocolates, anandamide present in them.

  • Binds to special receptors in the brain.

  • Giving us bliss and joy, thus making us love chocolates.

  • Some chocolates also contain substances like theobromine.

  • It is thought that this theobromine makes our brain produce anandamide by itself.

  • Making sure that we feel blissful after eating chocolates.

  • In addition to this, most types of chocolates contain sugar to make them taste sweet.

  • Sugar activates the reward system in the brain.

  • Due to which neurotransmitters like dopamine are released.

  • Dopamine gives us pleasure and makes us feel good.

  • As it makes us feel good, we tend to eat more chocolates to get the same feeling.

  • And thus, we get addicted to chocolates.

  • Moreover, whether it is milk chocolate, white chocolate or dark chocolate.

  • There are numerous varieties to choose from.

  • Also, there are dry fruits like raisins, almonds, cashew nuts, etc. which we generally like.

  • When these dry fruits are added to chocolates, the desire to eat chocolates increases.

  • Also, according to a study.

  • It is observed that salt suppresses bitterness and increases sweetness.

  • Hence, while preparing desserts like chocolate cakes, cookies, brownies, etc.

  • A little salt is added to them, making the desserts more inviting and tempting.

  • Thus, we easily get attracted towards them.

  • How tall can we grow?

  • I can grow as big as the Eiffel Tower.

  • Stop bluffing.

  • Height is determined by a number of factors.

  • One of them is our genes.

  • We inherit our genes from our parents.

  • Hence, these genes will make us grow approximately as tall as our parents.

  • In addition to this, factors like nutrition, physical health, hormones, etc.

  • Also affect our height.

  • Now, if we grow taller than what we are at present.

  • Then we will not be able to support our body's structure efficiently.

  • For this, we would require much larger bones.

  • Or they need to be made of much stronger material.

  • In addition to this, if we were taller, the amount of blood in our body would be more.

  • Thus, making it hard for the heart to pump so much blood.

  • Besides this, the earth's gravity constantly pulls us down.

  • As a result, it prevents us from getting taller.

It's AumSum Time.

Subtitles and vocabulary

Click the word to look it up Click the word to find further inforamtion about it