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Interesting little experiment

"Ding Rinrin", when the bell rang, the teacher came into the classroom with a big smile on her face. "Students, have you brought all the eggshells?" "I brought it!" We answered with one voice. "But what can eggshells do?" "Be a tumbler?" We whispered to each other. "Today, we are going to do a small experiment with these two and a half eggshells. Before you do it, please guess, I use this pencil to stab the eggshell vertically, and see which half of the eggshell breaks first? " "The next mouth is broken first!" Most boys pointed to half a shell and said. "Mouth up first!" My deskmate said flatly. Many girls are sitting and hesitating. "That's great! Let's do it and see whose answer is correct. "

The teacher turned to a classmate for help. He put his mouth against the teacher's hand and pointed a pencil at the eggshell. As soon as his hand was released, the pencil fell on the eggshell, which was not broken. The second time I dropped the pencil, but it fell into the teacher's hand, and then fell to the ground. pencil lead broke it. The teacher took out another pencil, this time she made it herself. The pencil was dropped only twice, and the eggshell with the bottle mouth up was broken. Then, the teacher picked up the pencil and poked the eggshell with his mouth down. "Once, twice, three times ..." We counted them together, but this half eggshell looks like wearing armor, and it won't break after being stabbed for more than a dozen times.

"Yes! I guessed right! " The deskmate danced with joy. "good! Next, I will let the students do it themselves to see if this is an accidental phenomenon. " "Yes, don't be too proud!" We don't believe it.

After doing this little experiment ourselves, we finally understand that the same two and a half eggshells are tied vertically with a pencil, because the downward eggshell is concentrated, so it is easier to be tied; However, the eggshell with its mouth facing down is scattered and not easy to be punctured. No wonder all the workers and uncles in our school construction site are wearing face-down safety helmets. It turned out to be the same thing!

Small experiments contain great truth. This course is really interesting!

An interesting experiment

From grade one to grade four, science has always been my favorite subject. I have done countless experiments in science class, but among these countless experiments, the only thing I remember vividly is the coin experiment I did not long ago. In science class that afternoon, the teacher announced to us: "Today, I will do a very interesting experiment with you!" " ""yes! "As soon as the voice fell, the students cheered." Is it an experiment of throwing coins into the water? "A classmate is a prophet." That's right! Who has coins around you? ""me! Me! I have! The students are scrambling to hand in their coins. The experiment began, and the teacher threw coins into a full cup. I squeezed in front, my eyes wide open, staring at the cup tightly, for fear of missing any tiny link. " One, two, three ... "Coins" jumped into the glass one by one, and the water surface was rising. The teacher suddenly stopped and asked, "Students, guess what will happen next?" "Water will overflow! "The students said in unison." No! We continue to look down! ""Who has a coin? "The teacher" searched "six coins from his classmates and carefully put them into the water one by one. After the last coin plopped into the water, it turned 360 degrees in the water like a trained diver before falling into the bottom of the cup. At this point, the students were surprised to find that the water surface actually exceeded the cup mouth, and it was half a centimeter! The students immediately surrounded the teacher and asked why, but the teacher bought a pass and asked us, "What do you think? "We are all monks-we are all at sea. After repeated inquiries from the students, the teacher finally opened his mouth and said mysteriously, "This is the tension of the water surface. It is this invisible force that supports the water surface beyond the mouth of the cup without overflowing. "So that's it! We finally understood the truth. This experiment taught us that we should not draw arbitrary conclusions about anything, but be brave in exploration and practice in order to solve the mystery. There are many secrets in nature, and I believe we can solve many mysteries as long as we keep exploring.

An interesting experiment

"Volcanic eruption", you must have seen it on TV, but have you seen it with your own eyes? I have seen a "volcanic eruption", but this is a simulation experiment of "volcanic eruption", and I have done this experiment myself. Wow, "Volcanic eruption" is really fun. You can also contribute.

I brought a glass, a bottle of vinegar and a bottle of detergent, a pack of baking soda and a newspaper according to the experimental requirements. Pour some baking soda into the glass first, then some detergent, and then put the newspaper under the glass.

The experiment is about to begin. I poured some vinegar into the cup, and a miracle soon appeared. There was only some baking soda and detergent in the bottle just now. They are quiet. How did it turn into a bubble in a few seconds? Moreover, it was just a little bubble, but now it has been soaring. Only after more than ten seconds, it poured out from the glass mouth, overflowed the bottle mouth and flowed into the newspaper. At this time, I was excited and surprised, staring at the floating foam, for fear of missing any details. After about 18 minutes, the bubbles gradually disappeared. Ha, this experiment is so fun, so interesting!

Why is this? I quickly grabbed the book and read it. I didn't mention a word in it. Alas! I have no choice but to find a way by myself. Didn't Mr. Liu say in class that baking soda and vinegar will react chemically and produce many bubbles, just like soda water, shaking it will also produce some bubbles. So what role does detergent play? I've racked my brains but I can't figure it out.

In order to find out the mystery, I repeated the experiment and found that the reason why the bubble soared was because the detergent played a catalytic role. This is similar to the formation principle of pumice. This little experiment is really interesting.

Doing small scientific experiments made me understand the scientific truth while playing, and also exercised my ability to use my hands and brains. It is really the best of both worlds.

An interesting experiment

I like drawing since I was a child, and I can draw a lot of things at the age of five. Once, I painted a summer scenery, and I liked it very much. Very good, especially the frog on the lotus leaf is cut out with colored cardboard. I showed this photo to my father. After reading it, my father said, "I have only seen green frogs, not pink or yellow frogs!" " "I am very sad, pouting, tears in my eyes, I am going to collapse. Dad smiled and said, "Don't cry, don't cry. Dad will give you a magic trick to make the frog take off his yellow clothes. " "Is that okay?" I looked at my father incredulously.

Dad asked me to find a plate, paint, brush and hair dryer. Everything is ready. Dad also instructed me to carefully pick up the paper frog and put it on the plate. At this time, my father took out a bottle of liquid from behind, which looked no different from boiled water. I asked doubtfully, "What's the use? Just like water. " Dad smiled: "silly daughter, this is 84 disinfectant, not the boiled water you drank." But also harmful to human skin, so be careful when using it. ""oh. " I nodded, puzzled. Dad poured what he called 84 disinfectant into the plate. A miracle happened, and the pink frog turned white in an instant. I was dumbfounded, and the frog took off his clothes that were difficult to take off. It's amazing! I picked up the paper frog with my eyebrow clip and dried it with a hair dryer. "Although the frog has changed its appearance, isn't it green yet? ""Why don't you paint it green? "So I painted the frog green with a brush." Wow, the frog is more beautiful. Dad, how did you change? Teach me quickly! " "In fact, 84 disinfectant has changed. The color of the frog is acidic, while the 84 disinfectant is alkaline, so the color of the frog is gone. "

Oh, science is so wonderful and profound.

Remember an interesting little experiment?

I am a little boy who loves to explore new things. I heard that after cutting an earthworm into two parts, it will not only die, but also become two live earthworms! To prove this, I did an interesting little experiment.

The students said that earthworms could be seen everywhere after the rain. One day after taking a bath, I really found an earthworm beside the flower bed without any effort.

When I got home on Friday, I took out my art knife, put the earthworm on a piece of paper and thought confidently: I will definitely complete the experiment successfully.

The experiment began. I carefully cut the earthworm in half. Take a closer look, huh? How can earthworms be as still as dead? I was extremely depressed: did my experiment fail? Just when I was depressed, I suddenly remembered what my mother had said to me: "Don't give up when you encounter difficulties, my mother believes you can do it!" " "So, I cheer up and continue to do experiments. I took "100,000 Why Biology Articles" and began to look up some information about earthworms. I rummaged around and found the answer. Oh! It turns out that after the earthworm is cut off, the muscles next to the wound will tighten immediately, just like the door that was still open will close immediately. It's amazing! Earthworms are actually very regenerative, so that's it! After two or three days, the divided earthworm can become two complete earthworms! Seeing this, I seem to see the dawn of victory and have confidence again!

Two days later, when I went to see my earthworms again, I really found two small earthworms crawling around in the box! I told my mother about it, and she smiled and said, "Haha, our son will learn to do experiments by himself!" " "

This is a little experiment I have done before. Isn't it interesting?

I feel heavy because I failed to beat Weng.

Students, have you heard the story of Columbus laying eggs vertically? Columbus broke the egg and stood up. In fact, you can stand up without falling, but it takes about five minutes, which is really too much trouble. Because when the center of gravity is directly above the triangle, the egg can stand upright. When the center of gravity is not above the triangle, the egg falls. The so-called center of gravity refers to the point where the resultant force of gravity acts on all parts of the object. From this we can think of an object, which can not only stand up, but also cannot be pushed down. Needless to say, if you are smart, you will definitely think this is a tumbler. Interesting tumbler, no matter how hard you push, you won't fall down. Even if you put it sideways, it will stand in front of you. Why doesn't the tumbler fall?

Oh! On the one hand, because the top is light and the bottom is heavy, there is a heavy iron block, so the center of gravity is very low; On the other hand, the lower part of the tumbler is made into a smooth sphere. When it leans to one side, its center of gravity rises and it is in an unstable state. Under the action of gravity, it moves to a stable and balanced position. Due to the inertia of the sky, it will swing back and forth several times and finally stay in its original position.

Ah! It turns out that science is everywhere around us. In order to benefit mankind, we must do more scientific experiments, learn more scientific knowledge and study hard.

Why don't soybeans germinate

Last week, I did a novel experiment-incubating bean sprouts.

Grandma gave me some soybean seeds, but I don't think they are enough. I had to take them out of the plastic bag tied tightly by my mother. My mother said the beans in the bag can't hatch bean sprouts. I don't believe it, so I have to do the experiment. So I separated the two kinds of soybeans and hatched them.

According to the introduction in the book and the teacher's guidance, I put these two kinds of soaked soybeans between two layers of wet straw and drench them with water every morning, noon and evening. I think, how can the same bean sprouts not grow in the same way?

The next day, I gently opened the straw on the bean sprouts. The soybean seeds in my grandmother's house have expanded to twice the original size, and many beans have short and thick buds on their waists. But the soybeans planted by my mother only grow fat and don't sprout. What's going on here?

On the fourth day, grandma's bean sprouts grew much taller, but mom's soybeans changed color, from light yellow to dark yellow, and some of them became light black. It seems that I am really going to be "unlucky" by my mother.

On the fifth and sixth day, time passed day by day, and the bean sprouts hatched with grandma's soybeans grew taller and taller, longer and more tender, with jade pillars and golden tops, very beautiful! But mom's soybeans are rotten. Only then did I believe what my mother said was true, but why? I have to ask my mother for advice. My mother smiled and said, "Although the beans are dry, they still need to breathe. Your grandmother's beans are hanging under the eaves, and the air is fresh. Of course, breathing is not a problem. The soybean in that plastic bag is dead because the mouth of the bag is tightly tied, there is no ventilation and it can't breathe. " "Oh, so that's it!" I said thoughtfully.

Unexpectedly, dried soybeans will suffocate. Life is full of science!

"I'm so happy today. I finished my homework in half an hour. Great!

"I said to myself. What do you do with the rest of your time?

I should go and see the little goldfish my mother bought. I walked quickly to the front of the flat fish tank, and the fish seemed to welcome me and swim to me. Among them, the lion-headed goldfish has a big head and a red and white tail, which seems to show off its beauty. It suddenly occurred to me: Why should fish control their balance in water?

I observed that the fish kept swinging while swimming. Can fins and tails work? In order to verify my guess, I made a bold experiment. I prepared small scissors, fishing nets and gauze first. Then I fished out a grass carp to feed the tortoise with a fishing net. The fish seems to be aware of the danger-struggling desperately. I silently said to the little fish, "Don't be afraid, little fish, just give it once for the success of the experiment!" "

"I stuck the double-sided tape on my thumb and forefinger and stuck the small fish. I picked up the scissors carefully and cut off the fins of the small fish. After cutting, I gently put the bald fish into the fish tank. At first, the little fish struggled for a while and then sank to the bottom of the water. After a long time, it didn't swim again. It seems that my guess is correct.

I was still a little worried, so I looked it up in the encyclopedia. It really said: Fins make fish balance. The fish's tail controls the direction. Through this experiment, I feel how interesting it is to acquire knowledge through observation and experiment!

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I like insects and go outside to observe them whenever I have time. Today, I finished all my homework. Just when I was thinking about going outside to observe the insects, the dark night began to arrival, and God began to "cry"!

I looked at the sky and sighed, thinking: the weather was fine just now. It rained neither early nor late, and it began to rain just before I went out. When I was worried, my mother asked me to drink wolfberry tea. As soon as I saw Lycium barbarum tea, I became interested in it immediately. Because I saw a lot of Lycium barbarum floating on the top of the cup and a few Lycium barbarum at the bottom of the cup, I felt particularly strange. Why do some Chinese wolfberry float on the water and some Chinese wolfberry sink under the teacup? I thought about it carefully: maybe Lycium barbarum is like a ball, and there is air in it that can float on the water.

I started doing small experiments. First, I took out two pieces of Lycium barbarum floating on the water, put one of them in the water and flattened it with a pair of chopsticks. As I expected, Lycium barbarum really bubbled in the water. Then I took off my chopsticks to see if the Lycium barbarum would sink. I saw the Lycium barbarum sink slowly. Then I put a wolfberry on the bottom of the teacup with chopsticks and took off the chopsticks. The wolfberry slowly floated up and finally floated to the water. Well, I finally figured it out. It turns out that my guess is right. Because the air in the first medlar came out, it sank. And there was air in the second medlar, so it floated up.

Through this little experiment, I learned a truth. Lycium barbarum is like a ball. With air in it, it can float on the water, but without air, it will sink.

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I wonder if putting too much water or too little water can make mung beans turn into mung beans quickly? The other day, I did an experiment to test it. I first took two plastic boxes, paper towels and water, and two mung bean seeds. I put paper towels in two boxes first, then 50 drops of water in one box and 80 drops of water in the other box. Then I put two mung bean seeds in two boxes and wrote down the numbers. The one with more water is 1, and the one with less water is No.2. Finally, I put the box on the balcony facing south. Do all this well, my heart is full of sweetness, and I will know the result soon. I also guess that the group with more water will germinate faster. I stood quietly on the balcony, waiting patiently for this moment. I waited for about 2 hours and found that the seeds in box 1 were much bigger, while the seeds in box 2 hardly changed. I waited for about 3 hours and found that the seed skin of 1 box was broken, while the seeds of 2 boxes only rose a lot. I am secretly happy and continue to wait for the moment when the seeds sprout. About three hours later, I looked again and found that 1 had a foot sticking out, while No.2 only had a broken skin. I think: it will take some time to know the result! I waited for two hours. I saw the seeds germinate in the watery box. I let the seeds germinate faster. I cried happily: "I guessed right, I succeeded!" " "ah! This mung bean germination experiment has benefited me a lot!

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One day, the teacher asked us to guess whether ants were afraid of mothballs. I guess ants are afraid of mothballs; Some students speculate that ants are not afraid of mothballs, but no one can tell the mystery. So, everyone ran to the playground with curiosity and started the experiment.

We saw little ants crawling on the ground in a hurry, looking for food. Maybe ants are hungry! Taking this opportunity, we quickly stopped an ant and gently scratched it with mothballs on the way forward. Everyone shouted, "Go, go!" "Although I followed the call, I didn't think so in my heart, but I thought so: I will definitely not rush, and the ants will either detour or turn around and go again. I stared at the little ant nervously. At this moment, the ants bypassed the "obstacle" and moved on. " Ah, ah, I guessed right! "I'm a little happy at this moment. Seeing that the ant was about to disappear, we hurried forward and drew the second line of defense and the third line of defense, but it all bypassed this' trap' smoothly, and we couldn't help but' wow'.

We didn't believe it, so we drew a circle around the ant, and it was thicker than before. Then I thought: Hee hee, you naughty boy, look where you are going. I saw ants in the circle like headless flies. After a while, it seems to have a "trick" and turn around in the circle, as if to say: "I don't believe I can't pass the customs, I must succeed!" Sure enough, it rushed over and looked back at us, as if to say, "demo, you still want to set me up, you are still a little tender!" " "That's it. Let's row a few. Let's make some. We are happy with the results of our experiment, and I am also a little curious.

What's going on here? I came to the computer with this question. I looked it up. Oh! It turns out that ants know their way by smell, and mothballs will affect their judgment, so they will take a detour. How did you rush out later? Because mothballs are trapped in it for a long time, the smell will fade, and ants will rush out of the defense line. Seeing this, I thought: I finally uncovered the secret.

Through this experiment, I not only learned another knowledge, but also understood a truth: no matter what I do, I must practice it by myself, so that I can better remember it and get a correct understanding.

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On a sunny morning, the teacher came into the classroom with a smile and said, "Today, I want everyone to relax. Let's play interesting games! " "After listening to the teacher, the students seem to have nails on the bench and can't sit still any longer.

We played "Cat and Mouse". The teacher selected several students as "cats" and several students as "mice", and then explained the rules of the game: "cats" are not allowed to enter the "mouse hole". The teacher asked me to be the "master" of the family, and the rest of the students formed a big circle. The teacher asked us to treat weeds as "mice" and want to eat our own "food".

When the game officially started, the owner said to the cat, "I'll sell the vegetables first, and you stay here to look after the house." Don't let the mouse steal something to eat. " The cat nodded, and after the owner left, the cat began to implement its action plan: pretending to sleep, confusing the "mouse", trying to lure the mouse out of the hole and then eating it.

After a while, the mouse finally lost his temper, fidgeting and trying to steal something. It first shows its small head and looks around to see if there are any targets and prey. Suddenly, the mouse was pleasantly surprised to find a pile of delicious food in front of a cat sleeping late. He couldn't believe his eyes, and his mouth was watering. He walked carefully to the food, thinking: What good luck today! The food has been found and the cat is sleeping. God help me! I saw him boldly approach the food with great pride. Just as he was secretly pleased to get the food with his own hands, the cat suddenly opened its eyes and caught the mouse at once. The mouse struggled desperately in the cat's hand and cried sadly, "grandpa cat, please forgive me this time!" " I will definitely repay you. "But the cat is the natural enemy of the mouse, and it has no sympathy for it at all. Finally, the mouse became a plate of Chinese food, and the cat enjoyed a good meal. The students are holding hands and jumping around, very happy.

"Ding zero zero, Ding zero zero ..." A hurried bell rang and the students reluctantly returned to the classroom.

Ah! The game of "cat and mouse" is really interesting. I really want to play this game every day. How colorful our campus life is. ...

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Interesting experiment

In the book "Ideological and Moral Cultivation", there is an interesting experiment-"Eggs touch the earth". Seeing this topic, I suddenly became interested and wanted to do this experiment.

This experiment is like this: take a raw egg and wrap it with any material. Then throw it from the third floor and make it unbreakable. I was ready with great interest, but I didn't expect the first hurdle to beat me-the way of packaging. What kind of packaging should I use? I racked my brains and referred to other students' methods, and finally decided on a method: to spell a triangular frame with eggs in it. I think the tripod has many corners, which can make the corners touch the ground, thus reducing the vibration and keeping the eggs from breaking. To be on the safe side, I wrapped the eggs with two handkerchiefs and a sponge. Then make a triangular frame with a wooden stick and put the wrapped eggs in it. Then fix the frame firmly. I was still worried, so I took a big plastic bag as a parachute, put it on the rope and tied it to the frame. I read it again and again with joy, but I didn't think it was very good. I wrapped some napkins on three corners of the ground and it was over.

In the evening, my classmates and I excitedly took packaged eggs and prepared to do experiments. He was standing downstairs, and I climbed up the aisle between the third and fourth floors. When I went upstairs, I carefully closed the downstairs window to avoid hanging a "parachute" on the window. Everything is ready. I shouted to the downstairs, "Are you ready?" He said yes. I opened the plastic bag and threw it down. Then, I ran downstairs and heard him shouting happily in the corridor: "Like a parachute!" " "

I went downstairs to see if the egg was broken. The big end of the egg was broken, but I was still very happy. On my way home, I met Mr. Jiang, the math teacher. The teacher asked us the results of the experiment with great interest. Let's ask Mr. Jiang quickly. Teacher Jiang said with a smile, "The triangle angle is not enough. Moreover, the three corners that touch the ground should be extended, which can reduce the vibration. "

I got a lot of knowledge from this little experiment. Doing experiments is both interesting and informative. In the future, we must observe more and explore more, and be a person with a conscience in life!