Do you know that?/You know what? Open science course (the third season) is a series of popular science courses jointly organized by Science Communication Bureau of Chinese Academy of Sciences, Bureau of China Academy of Sciences and Basic Education Department of Ministry of Education. The following are 10 articles I collected for you about the third season open science course for your reference. Come and have a look!
Comments on the third season of open science class 1 scientific phenomena can be seen everywhere in our lives. As long as we observe carefully, we are good at finding problems around us and dare to ask questions to science. I found such a scientific phenomenon in my life. We see the stars shining, not because the luminosity of the stars has changed, but because of the occlusion of the atmosphere. The atmosphere is between us and the stars. When starlight passes through the atmosphere, it will be affected by the density and thickness of the atmosphere. The atmosphere is not absolutely transparent, and its transparency will change according to its density. So when we look at the stars through it on the ground, we will see that the stars seem to be flashing.
Why does the hair turn white when people are old? There is a substance called melanin in our hair. The more melanin, the darker our hair will be. Without melanin, hair will turn yellow or white. When human beings reach old age, various functions of the body will gradually decline, and the formation of pigments will be less and less, so the hair will gradually turn white! I also know why there are leaves. It's fall here. Leaves evaporate more water than in summer, but roots absorb less water than in summer. In order to reduce the water loss of trees, stem cells began to form separation layers. When the nutrients leave the leaves completely, the separation layer separates the leaves from the trunk and leaves fall off.
As long as you pay attention, science is everywhere. Last summer vacation, I did a small experiment. Take two cups and fill them with water. Then, put in an egg respectively. At this time, the egg will sink. Then, I put the salt into the cup spoonful by spoonful, and kept stirring to make the salt fully dissolve. A miracle happened. The egg in the salt cup seemed to have a magical power to hold it, and it gradually floated. Why is this? Once, I found the answer in the open sesame program of Children's Channel. It turns out that this is related to the density of water. The higher the density, the greater the buoyancy, and the lower the density, the lower the buoyancy. Salt is added to increase the density of water. When the density is high, eggs will float. This is why the world-famous Dead Sea is immortal. Nature is really amazing! I love science! I love nature!
The third season of Open Class 2 comments on the rapid development of modern science and technology. I want to know what changes technology has brought to us. When I came home from school, I asked my father.
Dad said that technology has brought too many changes to people. Like the invention of the compass, it promoted the development of navigation and trade, completed the great geographical discovery, and made mankind know the earth; The scientific and technological achievements of hybrid rice and super rice have increased grain output and solved the problem of feeding the world population; Satellites provide us with satellite cloud pictures and weather forecasts, and can also relay TV signals.
Humans have also invented many useful things: telephones, computers and televisions? These things are convenient for people to do something. Just like a telephone: even if two people are far apart, just pick up the receiver and dial a few numbers, and you can hear each other's voice and communicate with each other in a few minutes. It is not enough to have a telephone. Man has invented a computer that is better than telephone. The phone can only hear the voice of the other party, and the computer can communicate by text or video conversation, and you can see the other party. If there is a holiday, send an email and the other party will receive it in a few seconds, which can save paper and let others receive it quickly. The development of science and technology has improved our living standards and quality of life!
In the new century, science and technology will develop faster, make our human life more convenient and serve us at all times. So we should study hard and serve well in the future.
How to treat the third season of open science course? Do you know toothpicks? Do you know how toothpicks let us know about science? Only use your own observation and courage to do the experiment. Do you know balloons? Do you know static electricity? Next I will take you to discover the mystery of static electricity.
The experiment began. Let's prepare tools, toothpicks, water, sugar cubes and soap. Step 1: Carefully put the toothpick on the water. Step 2: Put the sugar cubes in a basin away from toothpicks. The toothpick will move towards the sugar cube. Step 3: Put the soap in the water and keep the toothpick away from the soap.
The next experiment begins. Tools are 2 inflatable balloons, 1 string, 1 piece of cardboard. Step 1: Inflate two balloons separately and tie a knot in your mouth. Step 2: Connect two balloons with a thread. Step 3: Erase static electricity. Step 4: Separate the two balloons. Step 5: put the cardboard between two balloons, and the electricity on the balloons makes them attracted to the cardboard.
Why? Because of static electricity. The electricity on one balloon repels the electricity on the other balloon. The electricity on the two balloons attracts them to the cardboard.
When you put the cube in the center of the basin, it will absorb some water, so there will be a small water flow in the direction of the cube, and the toothpick will move with the water flow. However, when you put soap into the basin, the surface tension at the edge of the basin is strong, so you will pull the toothpick out.
Thank you for doing the experiment with me.
The third season of the open science course, 40,000 worlds, no surprises. In class today, Teacher Lin said, "Did you hear me say' paper buds blossom'?"
After a while, everyone gave a chorus of "hmm". "Today, I will take you to do an interesting experiment. The name of the experiment is' paper bud flowering'. " The teacher picked up the schoolbag, took out a bag of watercolor pens from the schoolbag and took out a piece of paper in the shape of flowers. Then he took out a blue marker from his watercolor pen bag and drew his favorite color on the paper with the pen, and the paper bud was ready. Then the teacher folded the petals.
"In the future, everyone will gather here to watch." The teacher picked up a basin of water and put it on the platform, and the students flocked to the platform like a flood.
"Now I put the flowers on the water and put them smoothly." The teacher said seriously.
There was silence in the classroom, and all the students stretched out their necks like geese, staring at the water unblinkingly. That bud is like a little girl who just woke up from sleep. It stretched out first, stretching out one petal, then another, and soon spread out. It looked at us curiously and stared at it.
"Do you want to experience this experiment?" The teacher said.
"think!" We say.
"I'm ready for you." The teacher said mysteriously.
Everyone got a paper bud painted with pigment. As soon as I got the paper bud, I couldn't wait to fold it.
The teacher said, "Let's put the paper buds in the water together."
We did as we were told, and as soon as the paper buds entered the water, they rushed to bloom. They walked up bit by bit, looked up curiously, and then looked around slowly, as if they felt very fresh about everything around them. Those colorful flowers compete with each other and have the momentum of "spring can't close the garden". It took about a cup of tea, and all the paper buds showed charming smiling faces. These paper flowers are like a little girl lying lazily on the water.
In fact, this experiment is a physical phenomenon. The main component of paper is plant fibers, which are tiny capillaries. After the paper meets water, the water rises along the capillaries in it, making the fiber full, so the original folded petals open.
We suddenly realized that life is full of science!
Today, as soon as we got to the classroom, we began to have classes. But this class is really special! It turned out that Mr. Wang had two cups and a small piece of paper in his hand and said, "We are going to do an experiment today!" " "Experiment!" We cheered. After that, Mr. Wang began to do experiments.
The experiment began. Some students stood on the bench, some ran to Miss Wang, and even stood on the table! We saw that Mr. Wang poured a jar of water into the cup and buckled the paper on the mouth of the cup. Then cover the mouth of the cup with your left hand, press hard, and then cover the bottom of the cup with your right hand. Then I turned the cup over and moved my hand slowly. At this point, my heart is in my throat. I thought to myself: can this succeed? Everyone held their breath and waited for Miss Wang's "achievement". At this time, it seems that you can hear the sound of a needle falling to the ground. Suddenly, Mr. Wang let go of his left hand, and the piece of paper was washed down with a "wow" sound, and the water splashed all over the floor, and everyone burst into laughter. It turns out that Mr. Wang's paper is too small to cover the mouth of the cup, so air flows in, and the air inside and outside cancel each other out and disappear. However, Mr. Wang didn't lose heart and continued to do the experiment. Teacher Wang took another piece of paper, the same as before, but failed again this time. We laughed again. The teacher took another piece of paper, pressed it on the cup filled with water and turned it over. "Ah," we shouted. It turns out that teacher Wang succeeded. She held the cup high, and after a while, she put it down again and asked, "Why didn't the paper fall?" Later, the teacher called Zhang, and Zhang said, "Because when the paper is pressed on the cup, the air doesn't take up the position, so the paper won't fall." Teacher Wang said, "No, it's because there are things around us that are invisible and intangible. Its power is greater than water, and it is atmospheric pressure. Because we fill a cup with water, air can't get in, and then put a piece of paper on it without leaving a gap. On the contrary, the paper will not fall off. But if the water is not full, buckle a small piece of paper and the paper will be washed down. This is my second experiment. " "Oh!" We suddenly realized.
Through this experiment, I benefited a lot and learned the mysteries of nature.
During the summer vacation, my father took me swimming in the Olympic Sports Center. When I came to the swimming pool, I took off my underwear and went swimming. I swim happily. Suddenly I felt a little pain in my ear, but I felt that it was nothing serious, so I endured it and swam down for a while. Oh, no, my ear hurts again and I don't want to surface. So I asked my father, "Dad, why do I feel my ears hurt when I swim?" Dad told me, "Maybe you dive a little deep. The pressure of the water is too great for your ears, so it hurts."
So I became curious about the pressure of water and wanted to know what determines the pressure. When I got home, I flipped through "100,000 Why", and there were too few things written on it to understand. I looked up the information on the Internet and learned that the pressure of water is determined by its depth. The deeper the water, the greater the pressure, and the shallower the water, the less the pressure.
To this end, I did an experiment. The materials are: 1 rectangular vertical carton filled with milk, 1 rolled tape, 1 nail, 1 flat plate.
I put away the milk carton and poked three holes in both sides with nails. The positions of the three holes are bottom, middle and upper respectively. Then seal the three holes with adhesive tape, fill the carton with water, put the flat plate under the perforated side and tear off the adhesive tape. Do you know what happened? Is there a difference between three-hole water spraying? Of course not. The water from the bottom is sprayed farthest, followed by the water in the middle, and the water from the top is sprayed closest. This proves that the pressure of water varies with the depth of water. The deeper the water, the greater the pressure, and the shallower the water, the less the pressure. Therefore, the depth of my swimming pool is different, and the pressure felt by my ears is different.
In order to know what other factors are related to stress, I did another small experiment: I inserted a straw into the mouth of a small paper box and plugged it tightly. Then I use a straw to add water to the carton. When the water reached the suction pipe, the bottom of the small carton cracked. After many experiments, the results are the same. It turns out that water pressure is also related to weight. Because the bottom of the carton bears the maximum weight of water, the water pressure is the greatest, so the bottom of the carton cracks.
Pressure is everywhere, including water pressure and atmospheric pressure, which are closely related to our lives. The pressure is far away and close at hand!
Students, have you ever heard that a full glass of water can hold 100 paper clips? Let me tell you something!
On Saturday, I did a small experiment at home. The material is: 100 paper clips and a glass of water. I want to try how many paper clips can be put in a glass of water. I picked up a paper clip and threw it into the water, two, three, four … one by one. The newspaper said that you can put a hundred paper clips in the water, which is incredible! I don't believe it. Can you believe it? One hundred paper clips were all thrown into the water, but the water didn't move at all. What's going on here? It turns out that the paper clip is very light, floating on the water, and its strength in the water is too small. Even if you put 1000, it's okay.
Do you understand this knowledge? Science is also very particular, and there is more knowledge, waiting for you to explore together!
Students, today I will introduce a good friend to you. It is under our skin, it is under the beautiful fur of animals, it is in the big rows, small rows and ribs I eat, and it is also in our domestic garbage. This is our common bone. Let's explore the mystery of bones today!
The night before, I brought three chicken legs, one for me, one for my father and one for my mother. Then I gave my grandmother some meat. When we finished eating meat, I got three chicken bones. I washed them and put them in a bag and a schoolbag.
The next day finally came, and I sat in our position. Our group includes Zhang Shuming, Chen Xinting, Chen Jiamin and me. Science teacher Lin began to talk about precautions, including: be careful when using a knife, don't cut your hand ... After the teacher finished the precautions, we began to cut bones.
First of all, Shu Ming picked up the bone and looked at it and said, "The color of this bone is still gray, and it feels very slippery." So she picked up a knife and began to cut. She slid hard on the bone, but the bone still didn't move. I saw her blushing face, like a volcano about to erupt. I really can't stand it! I grabbed the knife and pressed my two fingers against the bone and began to slide, but there was no difference between sliding and not sliding, so we called the science teacher, who scared us to run around with a fruit knife. The teacher slipped on the bone only three times and the bone broke.
After the bone was cut, I couldn't wait to pick up the magnifying glass and put it on the bone. "Wow" is like this in the bones! I saw a white film of three or four millimeters. Why didn't I cut the bone just now? There is a hard white periosteum. Once again, we observed that it has a color like coffee milkshake mixed with brown and white, like bee pupa, with small holes, such as triangle, hexagon and circle. And the deepest layer, of course, is the bone marrow! I tasted it once or twice, and it tasted good. It's so empty inside, why are the bones so light? It turns out it's hollow inside! I am so surprised. I finally know the secret of bones. I'm so happy.
Comments on the third season of Open Science Class 9 As soon as the class started this afternoon, the teacher smiled and said to us, "Today we are going to do an experiment." Students are like monks in Zhang Er-they are all at a loss and don't know what medicine the teacher is selling. There is a big question mark on each of us. Then, we stared at a pair of curious eyes and began to watch the teacher do magic.
First, the teacher carefully picked up an egg from the lecture table. It's white and fat, so cute. Then the teacher took a bottle with half a bottle of water and put it on the table. Then, the teacher put the egg into the water again. The egg sank to the bottom. When it hits the bottom of the bottle, it makes a "dong" sound, like a diver. Then the egg shook a few times and stopped moving. Then the teacher asked, "Who can make the eggs float?" The teacher asked Tian Yue to answer. Tian Yue said, "Put the egg gently on the water, and it won't sink." The teacher did as she said. The teacher first took the eggs out of the water and put them on the water. Unfortunately, as soon as the teacher released his hand, he sank to the bottom of the water. We shouted "Ah" and were disappointed. This method is useless, and other students raise their hands again. I'm in a hurry, but I don't remember how to make eggs float from the water. The teacher asked Li Runze to answer it again. Li Runze in our class just likes to think. He stood up unhurriedly and said, "Just add some salt to the bottle." Those students who once held hands collapsed on the table like deflated balls.
At this time, the teacher took out her secret weapon-salt. She scooped up a spoonful of salt and poured it into water. Like an atomic bomb, salt fell to the bottom of the bottle and immediately a "white smoke" rose. The egg seems to be infected by its power and shakes a few times. At first, we thought it would float, but it didn't move as if it were drunk. It turned out that it fell asleep again. Teacher Wang added another spoonful of salt to the room, the same as last time, but a little floating. The teacher added a third spoon and a fourth spoon to it. The teacher took another pen to stir the salt, and the egg turned, like a propeller of an airplane, like a ballerina wearing red dancing shoes, and like a tornado, and kept spinning. Gradually, the water became clear and the egg showed its "little bald head". Like an island that has been sleeping for tens of thousands of years, it finally floated up. The students were in high spirits, cheering and clapping. Then, the teacher pressed the egg into the water with his forefinger. As soon as the teacher let go, the egg jumped out of the water like a spring, a pole vault and an inflatable ball. As soon as the "bald" egg touches the water, it seems a little uncomfortable. It sinks into the water first and then floats to the surface.
Why does salt float in water? Because the water is added with salt, the buoyancy increases and the eggs can float.
It suddenly dawned on me that science is everywhere. As long as you explore and discover with your eyes, you can find it.
Comment on the open science course in the third quarter 10 This semester, we added the science course. Mother said, "Science is hard to come by." Dad said: "science is very difficult, you have to work hard!" " "What they said makes me nervous. Is science really that difficult?
Rinrin Bell, the students cheered "Science class!" I'm both looking forward to and nervous. The science teacher came with a happy smile on her face. The teacher said, "My name is Wang. From now on, everyone will call me Miss Wang." He went on to say, "Our first class is to plant red mung beans." The teacher told us that each of us gave out seven red mung bean seeds. The teacher said: "soak the red mung bean seeds for 3-5 hours first, then put them in the soil and water them when the soil is dry." When I got home, I did what the teacher taught me. On the third day, I really grew red beans and mung bean sprouts. I am very happy.
In the second science class, Teacher Wang took us to observe what was on the big tree. I saw birds playing happily in the trees and thin branches dancing in the wind. How beautiful!
Now I love science class, because science class is very interesting. It taught me a lot. ?