字幕列表 影片播放 列印英文字幕 It's AumSum Time Hey guys. Hold on. Did you download my app from Google Play Store? Remember, it's called ''It's AumSum Time''. And follow my Facebook page. Now, let's guess the title of my next video. Some areas are brown or green or even butterscotch-colored. Then, why does it look red? Hurry up. Write your guess in the comments section below. Why does a flame always point upward?? Muahahaha. Because I told it to do so. Oh. Because of the flame, the air around the candle is hot. Rise hot air, as you are lighter. Come cold air. Take its place, as you are heavier. Now, cold air also gets heated and rises again. This continuous cycle of hot air rising, cold air rushing in, getting heated. Causes a swirling effect. And that, makes the flame point upward. Topic: Concave mirror. Why is your reflection upside down on a spoon? Looks like you are getting ready to go for a party. Why don't you stand here and then look into the spoon? Don't worry. Your image appeared upside down because of the inward curve of the spoon. The surface of the spoon which is curved inwards acts like a concave mirror. You look confused. Let me explain. A concave mirror is a mirror whose reflecting surface is curved inwards. Being curved inwards, it reflects or bounces back the light rays in a different manner. When you see yourself in a spoon which is like a concave mirror. The light rays from your face fall on the top of the spoon and get reflected downwards. While, the light rays from your feet fall on the bottom of the spoon and get reflected upwards. As a result, you see yourself upside down. Now, the point where all these light rays meet is called the focal point. When you stand beyond this point, only then will you be able to see an inverted image of yourself. However, if you stand before the focal point, the image will look upright. Topic: Archimedes' principle. Why do ships float? Good question. Give me minimum five years to unravel its mystery. Alright. Don't bother. To answer this question, we need to understand Archimedes' principle. Archimedes' principle states that an object partly. Or fully immersed in a liquid experiences an upward force called buoyant force. Which is equal to the weight of the liquid displaced by it. Oh man. It is too complicated. Okay. Wait, I'll explain. A ship has a long and wide base due to which the amount. The weight of water displaced by it increases. Now according to Archimedes' principle, the buoyant force is equal to the weight of displaced liquid. Hence, as the weight of displaced water increases. The buoyant force that is the upward force exerted by the water increases, making the ship float. What is déjà vu? It is a magical power. No. Déjà vu is a French term which literally means 'already seen'. As the name suggests, it is a strange feeling that the current situation has happened before. It is an experience in which places seem familiar, although you have visited that place for the first time. But what causes déjà vu? One of the prevailing theories suggests that sometimes. Visual information from one of our eyes is transmitted a little late to the brain. So information from first eye reaches the brain first. Now, when the information from the other eye reaches the brain a little late. Our brain receives the same information twice. Hence, the situation or place appears familiar. It appears as if we have seen it already, that is, we experience déjà vu. Can animals get a sunburn? Yes. Due to ultraviolet radiation of the sun, animals can also get sunburns. However, to protect themselves from the harmful radiation. Different animals have different biological defenses. For example, reptiles have scales, birds have feathers, animals like sheep. Dogs and cats have fur or hair, sperm whales have a special protein, fin whales have more melanin, etc. Does anybody have Captain America's shield? Please listen. Some animals even produce certain substances to protect themselves from the harmful radiation. For example, hippopotamuses secrete a fluid made up of red and orange pigments. Some fish, amphibians, reptiles and birds produce a chemical called gadusol. In addition to this, animals like rhinoceroses, elephants and pigs take mud baths. It is said that mud acts like a physical barrier between their skin and ultraviolet radiation. Thus preventing them from getting sunburns.
B1 中級 美國腔 為什麼火焰總是朝上?| 為什麼火苗總是朝上? (Why does a Flame always Point Upward? | #aumsum) 9 1 AumSum 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字