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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.

  • How do microwave ovens work?

  • They work with the help of Iron Man lasers.

  • No.

  • A microwave oven is basically a metal box containing a magnetron.

  • It heats or cooks food much faster and more evenly as compared to a conventional oven.

  • When switched on, the magnetron converts electricity into microwaves.

  • Microwaves penetrate the food and excite water, fat and sugar molecules, generating heat.

  • Thus, helping us to heat up or cook the food.

  • Also note that, conventional ovens heat the food from outside in.

  • Hence, the outer surface of the food is exposed to heat for a longer time, thus causing the food to cook unevenly.

  • However, in microwave ovens, as microwaves penetrate the food, the food is cooked more evenly in less time.

  • Thus, nutrient loss is less as it is exposed to heat for less amount of time.

  • How do igloos keep you warm?

  • I'm a little busy.

  • So, I'll tell you about it later.

  • Alright.

  • I'll explain.

  • Heat is a form of energy present in our body.

  • When the temperatures around us are low, we begin to lose heat.

  • The more we lose heat, the colder we feel.

  • Now, although igloos are made up of blocks of compressed snow, they keep us warm.

  • Stop bluffing.

  • How's that possible?

  • Compressed snow has air trapped in it and air is a bad conductor of heat.

  • Hence, the heat given off by our body does not get lost from the igloo.

  • It stays in the igloo, thus keeping us warm.

  • Besides this, we know that warm air rises up and cold air sinks to the bottom.

  • Hence, during night, eskimos, i.e., people living in igloos sleep at the uppermost part of the igloo to stay warm.

  • How do painkillers work?

  • They act like a sponge and absorb the pain.

  • No.

  • When something is causing us damage, such as tip of a needle or pencil, special cells called nociceptors send signals to the brain.

  • The brain then perceives it as pain.

  • However, when cells of our body are severely damaged or injured, they release chemicals like arachidonic acid.

  • Now, just like a key fits in a lock, the arachidonic acid fits perfectly in enzymes called COX-1 and COX-2.

  • Forming prostaglandin and other compounds.

  • These compounds increase the sensitivity of nociceptors due to which it pains or hurts more.

  • Now, the most common painkillers are aspirin and ibuprofen.

  • These painkillers work by attaching themselves to COX-1 and COX-2.

  • Thus blocking them and not allowing arachidonic acid to bind to them.

  • As a result, prostaglandin is not produced and the sensitivity of nociceptors decreases.

  • Hence, the pain begins to subside.

  • Why are planets round?

  • Because I commanded them.

  • You wish.

  • Planets are round because of the force of gravity.

  • Gravity acts as if it originates from the center of a planet and pulls each point of the planet towards it.

  • Hence, the only way for everything on the surface to be equally close to its center is to form a round shape.

  • However, planets are not exactly round.

  • They are roughly spherical.

  • This is because planets spin on their axes.

  • Just like a spinning top, right?

  • Absolutely.

  • When planets spin, things near the equator tend to move away from the center due to centrifugal force.

  • Resulting in formation of an equatorial bulge.

  • Because of this bulge, the equator of a planet becomes farther from its center than its poles.

  • Creating a roughly spherical planet.

  • Topic: Osmosis.

  • Why is grass killed if salt is sprinkled on it?

  • Hey.

  • What are you doing?

  • Don't eat the grass.

  • Fine.

  • As always, ignore me.

  • See, I warned you earlier.

  • Hey, Wait.

  • You are making it worse.

  • Don't do that.

  • Look.

  • You spoiled it totally.

  • Alright.

  • Don't cry.

  • I will tell you why this happened.

  • This happened because of a concept called osmosis.

  • Osmosis is the diffusion or movement of water molecules from a region of higher concentration of water.

  • Through a semi-permeable membrane to a region of lower concentration of water.

  • Do you think osmosis took place when we sprinkled salt on the grass?

  • You are right.

  • Normally, osmosis does not take place on a day to day basis.

  • Because the grass tries to keep the concentration of water same inside.

  • Outside its cells through the process of transpiration.

  • However, when we sprinkled salt on the grass, the concentration of salt outside the grass increased.

  • The concentration of water decreased.

  • As a result, the water present inside the plant started flowing outside due to osmosis.

  • Since most of the water flowed out, the grass drooped down and eventually, it died.

It's AumSum Time.

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微波爐如何工作?| 微波爐的工作原理 (How do Microwave Ovens work? | #aumsum)

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    AumSum 發佈於 2021 年 01 月 14 日
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