字幕列表 影片播放 列印英文字幕 It's AumSum Time 中 Can you guess the title of my next video? Hurry up. Write your guess in the comments section below. Why smoking makes people look old? So that we look more experienced and intelligent!! Naahhh!! Smoking makes people look old because things like cigarettes contain nicotine. Nicotine is a vasoconstrictor which means it narrows our blood vessels, restricting the blood supply. When the blood supply is restricted, our cells don't get the required oxygen and nutrients. As a result, our skin becomes dry and discoloured. In addition to this, the collagen and elastin fibers which keep our skin firm and elastic. Begin to break down much faster, leading to saggy and wrinkled skin. Also, when we smoke, we purse our lips and squint our eyes. Regularly repeating these actions may also cause wrinkles on our lips and around our eyes. In this way, smoking makes our skin dry, saggy and wrinkled, thus making us look old. Why is snow white? Coz it applies fairness cream!! Nooo!! Sunlight or white light is a combination of all visible colors of light. When light falls on an object, it may absorb some colors of light and reflect the remaining colors. The colors which are reflected by an object make up its color. For example, when light falls on an apple, it absorbs all other colors except red. Apple reflects red color, making it appear red. When light strikes coal, it absorbs all colors and does not reflect any color. Hence, coal appears black to us. Really!! I didn't know that!! Now, snow does not absorb any colors of light and reflects all of them equally. As the combination of all colors of light is white light, snow appears white to us. Topic: Anaerobic respiration. What is the cause of muscle cramps? Excess sleep!! Nooo!! Respiration is a process in which the cells of our body produce energy. Normally, our cells respire aerobically. In this process, the glucose with the help of oxygen is completely broken down to produce energy, water and carbon dioxide. Is this energy then used for all our activities?? Indeed!! However, during heavy exercise, our body cannot deliver enough oxygen to the cells of our muscles. Hence, in such situations anaerobic respiration helps us to produce some energy temporarily and thus continue our work. In anaerobic respiration, the glucose is partially broken down in the absence of oxygen to produce comparatively less amount of energy. A waste product called lactic acid. Now, one of the most prominent reasons for the muscle cramps is the accumulation of this lactic acid. Topic: Sublimation Why do mothballs disappear over time? Wow!! You have a nice collection of clothes!! But have you kept mothballs to protect them? Yaa yaa!! I had kept them a few months back below these clothes!! Ohh nooo!! Where did the mothballs go?? I had placed them right here!! Did you steal them?? No no!! I haven't stolen anything!! Mothballs disappear over time!! Do you know why? It is because of a process called sublimation. During sublimation, a solid on heating, converts directly into vapor without passing through the intermediate liquid state. Don't lie!! How is that even possible?? See, I also hid a burger here many days ago!! It did not disappear!! Oh gross!! Just throw that burger in the dustbin!! Not all substances sublimate. Mothballs are made up of naphthalene. Naphthalene has very weak intermolecular forces. Because of these weak forces, the mothball which is made up of naphthalene sublimates. i.e., it changes its state from solid to vapor. Now this vapor is either absorbed by the fabric or it escapes into the atmosphere causing the mothballs to disappear over time.