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  • It's AumSum Time

  • Which came first: Chicken or Egg?

  • I, me and myself.

  • You wish.

  • There are numerous debates and theories on who came first.

  • One popular theory is the Proto-Chicken Theory.

  • What is that?

  • During reproduction, two organisms pass on their DNA to the egg.

  • Each time, tiny changes or mutations take place in the DNA.

  • Over thousands of years, these changes create new species.

  • Experts theorize that one such new species was the Proto-Chicken.

  • Very similar to present day chicken.

  • When the Proto-chicken laid an egg, mutations in the DNA created the First True Chicken.

  • Now, which came first, depends on what we call the egg.

  • If we say that the Proto-Chicken laid a Proto-egg, which created the first chicken.

  • Then the answer is, Chicken came first.

  • However, if we do not call the egg a Proto-egg, and instead, call it a chicken egg, then egg came first.

  • Electric charge.

  • How does a plastic comb attract paper?

  • What?

  • You do not believe me?

  • Okay.

  • Let us try.

  • Take a plastic comb and bring it close to some pieces of paper.

  • Hey wait.

  • Do not laugh.

  • We need to do something first.

  • Rub the comb on your dry hair and then bring the comb close to the pieces of paper.

  • See, I was correct.

  • The pieces of paper got attracted to the plastic comb.

  • Do you think it is magic?

  • No, the reason behind this is electric charge.

  • Electric charge is the quantity of electricity held in an object.

  • There are 2 types of electric charges, positive and negative.

  • However, there are some objects where the positive and negative charges are equal to one another.

  • In such cases, we say that the object is electrically neutral.

  • So, was the plastic comb initially electrically neutral or electrically charged?

  • Initially, the plastic comb was electrically neutral.

  • That means it had equal number of positive and negative charges.

  • Hence, it did not have the ability to exert a force and attract the pieces of paper.

  • So, after rubbing the plastic comb on our dry hair, why was it able to attract the pieces of paper?

  • I will tell you why.

  • When we rubbed the plastic comb on our dry hair, it gained an electric charge.

  • Once it got electrically charged, it got the ability to exert a force on the pieces of paper and attract them.

  • This charge is called as static electricity.

  • However, do you think, like a plastic comb, a metallic comb will also attract the pieces of paper?

  • No, you are wrong.

  • A metallic comb will not attract the pieces of paper like the plastic comb.

  • Wondering why is that so?

  • It is because plastic is not a good conductor of electricity.

  • It does not allow the electric charges to flow through it onto the earth.

  • As a result, the charges build in the plastic comb.

  • Making it electrically charged and enabling it to attract the pieces of paper.

  • However, metal is a good conductor of electricity.

  • It does not let the charges build in it.

  • It allows the electric charges to flow through it onto the earth.

  • Thus not allowing the metallic comb to get electrically charged.

  • As a result, the metallic comb does not attract the pieces of paper.

  • Heat transfer.

  • Why are cloudy nights warmer than clear nights?

  • Hey.

  • Look at the weather outside.

  • It is too cloudy.

  • No.

  • Do not go near that bonfire.

  • It is going to be warm tonight.

  • You do not want to listen to me, right?

  • Alright.

  • Go ahead.

  • Look.

  • I told you.

  • At least now will you listen to me.

  • During the day, our earth receives light from the sun and gets heated.

  • Now, during a clear night, that is, when there are no clouds.

  • This heat easily escapes through the atmosphere into space, resulting in cooling of the earth.

  • Now, to understand what happens on a cloudy night, let us heat the earth once again.

  • In this case, the clouds act like a blanket, preventing the heat from escaping into space.

  • Since the heat remains in the atmosphere, cloudy nights are warmer than clear nights.

  • Density.

  • Why do firemen crawl in smoke filled rooms?

  • Hey.

  • Remember, the upper part of the room will be filled with smoke.

  • So, crawl while you are going inside.

  • I will not.

  • My legs will become dirty.

  • Why don't you listen?

  • Look, you are not able to breathe properly as you have inhaled a lot of smoke.

  • This happened because you did not care about the density of air.

  • Well.

  • I know all about cavity, but what's this new thing called density?

  • Do not worry.

  • I will explain.

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

  • Lesser the density, lighter will be the object and greater the density, heavier will be the object.

  • So in this case, what is lighter, the air or the smoke?

  • Wait.

  • Let me think.

  • I guess the answer is smoke.

  • Yes, you are absolutely correct.

  • Smoke is lighter than air.

  • As it is lighter, it rises up in the room and occupies the space at the top.

  • Hey.

  • Where are you going?

  • It is not over yet.

  • The air being heavier than smoke tends to remain below.

  • Hence, if we crawl, we will get sufficient oxygen to breathe.

  • We can safely come out of the room without being suffocated.

  • Nerves.

  • Why don't we feel pain when we cut our hair?

  • Because if it would, then we would have got angry on our hair dressers.

  • You are just impossible.

  • Wait.

  • I will explain it to you.

  • Inside our body, there is a network of nerves.

  • These nerves help us to sense our surroundings and feel pain, touch, etc.

  • By sending messages to the brain.

  • So, do the nerves of my hair not know how to send a message?

  • No.

  • Generally, the part of our hair above the skin is made up of dead cells.

  • It does not have any nerves.

  • Hence, when we cut our hair, due to the absence of nerves.

  • Our brain does not receive any messages of pain.

  • As a result, we don't feel any pain.

  • Friction.

  • Why is it difficult to pull a boat on the beach than on the sea?

  • Hey.

  • You will find it difficult to pull the boat on the beach.

  • Pull it on the sea.

  • There it will be quite easy.

  • Indeed.

  • Why not?

  • Fine.

  • Do not listen.

  • I am so tired.

  • At least now try to pull the boat on the sea.

  • It is quite easy, right?

  • Do you know why?

  • This is because of friction.

  • Friction is the force which opposes the motion of an object.

  • It always acts in the direction opposite to the direction of motion.

  • The amount of friction depends upon the texture of an object and the surface on which it is being moved.

  • Rough textures or surfaces offer greater friction as compared to smooth textures or surfaces.

  • Do you want to say that my brand new boat has a rough texture?

  • No.

  • Even though the texture of the boat is almost smooth.

  • The small particles of sand present on beach form a rough surface.

  • Hence, when we pull the boat on beach, the sand particles offer greater friction.

  • Oppose the motion of the boat, thus making it difficult to move the boat on a beach.

  • However, the sea being a liquid, forms a smooth surface.

  • Hence, when we pull the boat on sea.

  • It offers less friction, thus making it comparatively less difficult to pull the boat on sea.

  • Forced vibrations.

  • Why does a guitar have a hollow box?

  • To keep clothes while traveling.

  • Not at all.

  • Wait, I will explain.

  • Whenever we strike an object, it vibrates.

  • Sometimes, these vibrations influence other objects to vibrate.

  • The vibrations which take place under the influence of an external periodic force are called forced vibrations.

  • So, whenever I see delicious food, my stomach starts to vibrate.

  • Is this a type of forced vibration?

  • Please concentrate.

  • A guitar has a hollow box which holds quite a huge volume of air.

  • Now, when we strike its string, it starts to vibrate.

  • These vibrations influence the air in the hollow box, producing forced vibrations in them.

  • Now we know that vibrations in air produce sound.

  • Hence, as a huge volume of air is vibrating, the sound produced is louder.

  • Pneumonia.

  • What causes pneumonia?

  • The letter P.

  • No.

  • Pneumonia is a lung infection caused by microorganisms.

  • Which generally leads to difficulty in breathing.

  • Normally, we inhale oxygen rich air which reaches our alveoli.

  • Alveoli are surrounded by blood capillaries.

  • Here, the oxygen through the walls of alveoli diffuses into our blood.

  • However, sometimes we also inhale harmful microorganisms.

  • Mostly, the cilia and mucus in our respiratory tract trap these microorganisms.

  • Which are then expelled while coughing.

  • But sometimes the microorganisms don't get trapped and reach the alveoli.

  • There they start to multiply, causing lung infection, that is, pneumonia.

  • Oh no.

  • Now what to do?

  • Now, to protect ourselves, the immune cells start attacking the microorganisms.

  • Causing inflammation and accumulation of fluid in the alveoli.

  • As a result.

  • The inhaled oxygen cannot get easily diffused into blood, thus causing difficulty in breathing.

  • What is earwax?

  • It is a wax used to make candles.

  • Gross.

  • Not at all.

  • Earwax is used to lubricate and protect our ear canal, middle ear and inner ear.

  • But how does it form?

  • Our ear canal consists of special glands.

  • They produce an oily and waxy substance called cerumen.

  • Cerumen moisturizes our ears.

  • It traps dust and dead skin cells, keeping our ears clean.

  • Besides this, cerumen also has antibacterial properties.

  • When harmful microbes try to enter deeper into our ears, the cerumen traps and kills the microbes.

  • These dead microbes, dust, oil and dead skin cells together form the earwax.

  • 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.

  • Hello

  • Why does our voice sound different when recorded?

  • Our inner ear detects sound vibrations, informing our brain about the voice or sound.

  • Thus, helping us hear.

  • But did you know that when we speak, we hear our own voice in two different ways.

  • What?

  • In two different ways.

  • Indeed.

  • The first way is through our outer ear.

  • Our voice travels to the outer ear, creating vibrations in the eardrum.

  • These vibrations eventually reach the inner ear.

  • While the second way is through our flesh and skull bones.

  • However, they are better at transmitting deeper, lower frequency sounds.

  • As compared to shriller, higher frequency sounds.

  • As a result, the combination of sounds obtained from the two ways makes our voice appear deeper.

  • Now, when we hear our recorded voice, we only hear the voice which has traveled through our outer ear.

  • Hence, our voice sounds different when recorded.

  • Why is yawning contagious?

  • Because everybody wants to sleep.

  • No.

  • There are a couple of theories which explain why yawning is contagious.

  • One of them suggests that it is a sign of empathy.

  • Empathy is the ability to understand and share others feelings.

  • For example, when people around us are happy and smiling, they make a positive impact on us.

  • Hence, we also feel good and begin to smile.

  • Moreover, the closer we are to someone such as our parents or friends.