Remember what kind of little experiment, remember an interesting little experiment

It's better to write the problem in detail...

Once, I was casually reading a magazine when a strange illustration caught my eye, and when I looked closely, it turned out to be a small experiment "making my own little rainbow", and I was very curious, so I decided to try it immediately.

I quickly gathered water-soluble pigments, beakers, and other materials and started making them. After selecting the paint and squeezing it on the canvas as described in the magazine, I picked up the pen and was about to dip it in the water, when I realized that I was so anxious that I only took the cup and left it unfilled. "Oops, I was so sloppy that I forgot to fill the water!

I blamed myself and hurriedly took the water cup to the sanitary water. After picking up the water, I quickly picked up a small piece of paper and poked each color of paint, and I breathed a sigh of relief: "Ahhhh

Fortunately, the color hasn't dried yet, otherwise all the work would have been wasted. "I diluted the pigment well with water, and then slowly poured the red pigment into the beaker, which took up exactly one-seventh of the beaker. Then I poured half a spoonful of salt into the orange pigment to melt it completely, and then I put the purple pigment into a beaker, and the orange pigment miraculously floated on top of the red pigment'Above, I am very happy.

Melt one spoonful, one and a half spoonfuls, two spoonfuls, two and a half spoonfuls, and three spoonfuls of salt into yellow, green, cyan, blue, and purple respectively. However, there was a pigment that could not be mixed with the salt, so I started adding water. I finally poured all the paint into it.

The layers were so beautiful that I was excited: "What a fun little experiment!" ”

However, the more salt is added to the upper layer, why is that? I still don't understand.

Class Four (1) Zha Huiwen.

In the nature class, the teacher smiled and said to us: "Today we are going to do a small experiment to ——— the tension of water, and everyone should be optimistic about the process of the experiment!" The whole class was curious, their eyes wide open, and they waited for the teacher's experiment to begin.

The experiment began, and the teacher first filled the cup with a full glass of water, and placed the cup on the table, with more than two dozen coins on the side of the cup. The teacher said, "Look at the water at the mouth of the cup."

The water is flat! The students shouted in unison. Next, the teacher picks up a coin and slowly slides it into the water along the rim of the cup.

Everyone looked at the water very nervously, but the water did not overflow. What's going on? We all want to give it a try.

The teacher chose some classmates, and I was also chosen. The teacher gave each of us a coin and asked us to draw the coins into the water one by one, and the amazing thing was that so many coins went into the water, and the water did not overflow at all. Finally it was my turn, and I was afraid that the water would overflow, so I carefully put the coin into the water.

The coin fell to the bottom of the cup like a well-trained diver, and the water still did not overflow, and we were surprised to find that the water surface had protruded beyond the mouth of the cup.

The teacher told us, "The reason the water doesn't overflow is because the water has tension." The tension of water is an invisible force that supports the surface of the water beyond the rim of the cup. "After listening to the teacher's words, it dawned on us.

During today's class, the teacher asked us a strange question: why didn't a little boy lie on the sea and read a book? As soon as the teacher's words fell, the students began to talk about it.

Some classmates said that he was lying on the swimming ring; Some say that he is lying on the Dead Sea. The teacher just smiled and didn't say anything. Because there is no scientific basis for these reasons.

Out of nowhere, the teacher conjured up a clear plastic cup, a raw egg, a spoon, and a small bag of salt. The teacher first asked a student to fill a cup with half a glass of water, and then gently put the egg in it, and the egg sank in an instant. I stared intently at the cup.

Then, the teacher took a small spoon and added salt to the cup one by one. We understood that the teacher was going to add a certain amount of salt to the cup to make the eggs float. However, four or five spoonfuls of salt were added.

The egg just twisted a few times with great reluctance, and then sank to the bottom of the cup and went to sleep. The classmates were anxious and shouted, "Teacher, add salt quickly."

The teacher added a few more spoonfuls of salt, but the eggs were still lying lazily at the bottom of the glass. At this time, we realized that the salt added was also like eggs, sinking to the bottom of the cup! So, the teacher took out the eggs and stirred them vigorously with chopsticks for a while, and the water became cloudy and the salt was gone.

When the teacher put the egg in again, it no longer slept as before, but stood up. It seems that success is not far off!

The teacher added a few more spoonfuls of salt to the cup, and after about half a minute, the egg floated, albeit in a state suspended in the water. The teacher took the chopsticks and stirred them in the water a few more times, and the eggs danced gracefully in the water, which was so beautiful!

Then, the teacher added the last few spoonfuls of salt to the cup, and ah, the egg finally poked its head out of the water, and the students let out an exclamation of "wow". Then press the egg down with chopsticks, and it dances like a ballet dancer in the water and rises out of the water. I think:

The fact that a little boy can lie on the surface of the sea and read a book must be because the sea water contains a lot of salt.

Finally, the teacher told us the answer to the question we asked in the lesson: the sea where the little boy was lying down and reading was the "Dead Sea". The salt content of seawater is more than 30%, and people will not sink if they lie down.

Today's experiment has taught me another common sense of natural science.

What experiments have you done?

A lot of the little experiments are interesting.

There are a lot of science experiments in the third grade of elementary school. For example: Looking at colorful light with a prism can be written like this:

1: Today, the science teacher taught us to do an interesting experiment--- what or something, 2: how to do the experiment:

3: This experiment allows us to see the colorful sunshine. I never thought I could create a rainbow on my own, it's so much fun to be real...

This is ready to be written.

Remember a fun little experiment.

But what can eggshells do? "Do you want to be a tumbler?" "We whispered. "Today, we're going to do a little experiment with these two half-eggshells. Before you do that, please guess that I use this pencil to hang towards the eggshell.

Stab straight down, and see which half of the eggshell breaks first? "The mouth will be broken first!" Most of the boys pointed to the half of the eggshell and said. "The mouth is up first! My tablemate said categorically. A lot of girls are sitting, hesitating.

Indecided. "That's good! Let's do it and see who has the right answer. ”

The teacher called a classmate to help, and he pointed a pencil at the eggshell of the teacher's hand, and as soon as he put his hand, the pencil fell.

On the eggshell, the eggshell is not broken. The second time the pencil fell, but it fell to the teacher's hand, and then fell to the ground, and the lead of the pencil broke. The teacher took out another pencil, and this time she went out herself, and the pencil fell just twice, and the eggshell broke with her mouth facing up. Then, the teacher took a pencil and stabbed it at the eggshell that was pointing downward. "One, two, three......"We counted them together, but the half of the eggshell was pierced a dozen times in a row, as if it were wearing armor.

The next is not broken.

yeah！I guessed it! The table danced happily. "Good! Next, I ask the students to do it themselves to see if this is an accident. "Yes, don't get complacent too soon! "We're not convinced.

After doing this little experiment ourselves, we finally realized that the same two halves of the eggshell can be pierced vertically with a pencil, because the force on the eggshell facing down is more concentrated, so it is easier to be punctured; The mouth-facing eggshell is dispersed by force, so it is not easy to be punctured. It's no wonder that the uncles of the workers at the construction site of our school wear hard hats with their mouths downward, it turns out that it is the same truth!

A small experiment contains a big truth, and this lesson is really interesting!