小朋友,你们相信针会浮在水面上吗?
Children, do you believe the needle will float on the water?
星期六的上午,我和妈妈做了针浮在水面上的试验。首先妈妈找来了一根针、一个夹子和半盆清水。我用夹子夹着针扔了下去,针很快沉下去了。后来我反复试验,最后我用夹子夹着针小心的把它放到水面上,随后慢慢地移出了夹子,针就浮在水面上了。“妈妈,我成功了,针浮在水面上了。”我冲妈妈高兴地大喊。
On Saturday morning, my mother and I did the experiment of needle floating on the water. First, my mother found a needle, a clip and half a basin of water. I threw the needle in a clip and it sank quickly. Later, I tried again and again. At last, I carefully put it on the water surface with a clip. Then I slowly removed the clip and the pin floated on the water surface. "Mom, I made it. The needle is on the water." I shouted to my mother happily.
为什么针会浮在水面上呢?我查了查资料,原来是因为水的表面有一定的张力,针的重量比张力小,所以针能浮在水面上,如果用手将针扔下去的话,张力被破坏了,针就沉在了盆底。
Why does the needle float on the water? I checked the data. It turns out that there is a certain tension on the surface of the water. The weight of the needle is smaller than the tension, so the needle can float on the water surface. If you throw the needle down by hand, the tension will be damaged and the needle will sink on the bottom of the basin.
看着浮在水面摇摇摆摆的针,我心里真高兴!
I am so happy to see the needle floating on the water!
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