1, scientific composition

Science has a peculiar charm, a magical power, it is everywhere, and it often exists in our lives.

One day, my mother wanted to use a drink bottle and let me wash it. I washed the bottle with warm water, poured out the water and tightened the lid. After a while, I suddenly found the bottle was flat! I was surprised and asked my mother why. My mother smiled and said to me, "Go and find the answer yourself." .

So I went to read a book, looked it up on the Internet, and finally found the answer. It turns out that hot water heats the air in the bottle, and the air expands, which causes the bottle to expand. When the temperature in the bottle drops, the air in the bottle contracts again. At this time, the air pressure in the bottle is lower than that outside the bottle, so the air pressure outside the bottle deflates the bottle. Haha, I see, so this is the principle that air expands with heat and contracts with cold.

There is science everywhere in life. As long as we pay more attention, we will find the footprint of science and let science serve us.

2. Hairball trimmer

Do you have any sweaters at home? I think you must promise. Every household has sweaters at present, but have you ever observed sweaters? If you look carefully, you will find that there are many small balls on the sweater, which are made up of the hairs on the sweater. This will not only hinder the appearance, but also make you feel very uncomfortable. If it is not handled properly, it will damage the whole sweater, which is even worse.

At this time, it's the hair ball trimmer's turn to play. I saw it running at full power, blowing hairballs. I saw that all the hairballs were gone and the sweater was clean. Just when I was surprised by this hairball trimmer, a cloud of doubt suddenly rose. How to trim the fluff trimmer?

While I was wondering, my father spoke and asked me to find the answer myself.

I took out the instructions, studied them carefully and began to dismantle the trimmer. I turned off the switch of the repairer first, then unscrewed and pulled out the outermost outer knife net, and then took out the main round knife. The blade body was extremely sharp, and then I saw the fan blades composed of four erected boards. When I turn on the switch, it will turn quickly. There is a huge gap at the bottom of the fan blade, and the hair ball falls from this gap and falls into the storage bin, where it is kept.

It turns out that this trimmer uses a motor to drive the blade to rotate, and the blade is connected with a round knife. As soon as the blade rotates at high speed, so does the circular knife. The outer knife net separates the clothes from the round knife to prevent direct contact with the clothes. There are many small holes in the outer cutter net. When the hair ball contacts the clothes, the hair ball extends into the outer knife net and is directly cut by the circular knife. The cut hair ball fell from the side of the round knife to the fan blade below.

In the case of high-speed rotation, the four boards erected on the blades "hit" the hair balls into the storage bin like playing badminton. During the experiment, I found a problem: as soon as I unscrewed the outer knife net, the maintainer stopped rotating.

Is there no electricity? Then why did you turn so fast just now? After many experiments, I found that there is a button next to the fan blade, just like the lamp on the refrigerator, there is a button. This button will be pressed after the outer cutter net is tightened. When pressed to the bottom, the protection function is turned off and the trimmer works normally.

It turns out that the hairball trimmer still has so much knowledge!

3. Small scientific papers

There are many scientific and technological things around us, such as rice cookers, computers, televisions and electric lights. Our science is really getting better and better, which is created by everyone's efforts.

Science brings us many benefits and makes our life more perfect! The efforts of scientists have not been in vain! The former yellow mud road → mud road → cement road → has evolved into today's asphalt road, which shows that our traffic has improved. The previous moonlight → fireflies → oil lamps → kerosene lamps → evolved into today's electric lights, indicating that our fire lamps have improved.

At the moment, there is something new. The details are as follows: Recently, we found that there would be a car running through the traffic lights on our road, so we installed a camera. Once the car runs a red light, it will be fined 200 yuan. That thing will film the scene! My uncle is an example because of the curiosity of my cousins. Now we can cross the road safely! How convenient!

We have cars on the road, ships on the sea, planes and rockets in the sky ... we have got rid of the "two-legged vehicle", which is a scientific progress. Science will bring us a perfect life!

4. Small scientific papers

One day, my mother came back from the mall and said mysteriously to me as soon as she entered the door, "Jojo, I want to show you something." "What is it?" I asked. "It's a cactus!" "What?" I was shocked. "What's so good about cactus!" "Don't look down upon this cactus. Don't we have a computer at home? It can not only prevent ultraviolet rays, but also purify the air! " "Really? Can I keep this cactus? " My eyes lit up and I begged my mother. She agreed and told me how to raise it.

I watered it every ten days according to my mother's method and watched it grow and produce many bright flowers. I forgot to water the exam. Until the end of the exam, I came home and sat at my computer desk, suddenly remembering that I hadn't watered it for 1 month. I took a closer look and found that it was not dead, but alive. I feel very strange: other flowers will wither as long as they are not watered for a few days, while cactus is fine and growing well without watering for so many days.

So, I turned on the computer to check the information. At first, cacti lived in the desert. It has fleshy stems and prickly leaves. The stem can store a lot of water, and the leaves can reduce the loss of water, so that the cactus can adapt to the harsh life and environment in the desert, so it grows well!

I also learned from the data that cactus not only has the necessary ultraviolet radiation protection potential, but also can purify the air to adapt to the harsh life and environment in the desert. Unlike most plants, cactus releases carbon dioxide during the day and absorbs carbon dioxide at night to release oxygen, so it is still natural oxygen.

Through this incident, I understand that life and science are actually closely linked. As long as you observe carefully, you will find more!

5. Small scientific papers

I want to know how flowers change color. There must be a mistake! But it's all in the newspaper. Could it be fake? Yes, try it. The truth will come out, won't it?

So my mother and I started to follow the instructions in the book. I found two cups, some white vinegar and a daffodil. The experiment began. I first poured half a glass of water into two cups, then put some caustic soda in one of the cups and put the flowers in it. But after a while, the flowers were "safe and sound", which made me more suspicious, so I poured all the caustic soda in. Great, the flowers have finally changed color.

Then I put the changed flowers in a cup with white vinegar, and sure enough, the flowers turned white again. I can't believe it's true. I looked up "100,000 Why" and learned that daffodils contain anthocyanins. If soaked in alkaline solution, the flower will change color, and the discolored flower will turn white if soaked in acidic solution again.