It has been half a century since the Apollo moon landing. Even today, some people still question the authenticity of the moon landing. They call it a masterpiece made in a ground studio and a science fiction blockbuster filmed in a different way. There are endless doubts. Unexpectedly, in recent days, a blogger made shocking remarks on Twitter. He claimed that the space teaching project carried out in China’s space station was completed on the ground. Isn’t this questioning our space station? Is the project fake? If it is only foreign netizens who question it, there is no problem. The key is that it spreads to the country and some domestic netizens are also led astray and start to question it, and the problem becomes bigger.
What happened is this. During the Shenzhou 13 mission, three astronauts conducted a space teaching project on the space station. As you can see from the picture, a water cup rested quietly on the table, along with it What is left standing is the water in the cup. This is where the doubt comes from. The foreign blogger believes that in previous space station projects, the water in the space station was in the shape of a ball and floated in the space station. It is very interesting. Why does the water in this cup sit quietly in the cup? , and the cup doesn’t float?
In fact, this question does not constitute a question at all, and there is no need to reply to this question. However, the official explanation has also been given. The main purpose is to relieve the doubts of these domestic netizens who have been led astray. Have you ever thought about whether the cup might have been fixed on the table in advance for better experimentation? Is it possible that the reason why the water did not fly out of the cup is because of the physics knowledge we learned in the second grade of junior high school?
The surface tension effect of water is explained in this physics textbook for the second grade of junior high school. In other words, we should have understood this physics knowledge by the second grade of junior high school, and the picture at that time was that a bug can walk on the water. , this is the surface tension effect. The surface layer of water produces tension acting on any boundary along the surface due to the uneven gravitational force of the molecules. Since the distance between water molecules in the surface layer is larger than that inside the liquid, the interaction between the molecules appears as gravitational force. As a result, the surface layer Liquids have a tendency to shrink automatically, which is a force that causes the surface area of the liquid to shrink.
In the space teaching experimental project, the experimenter covered the mouth of the cup with a film in advance, used a syringe needle to inject water into the cup through the film, and then removed the film, which presented the scene during the experiment.
's explanation for this question is very simple, but the questioner did not search for relevant reasons in advance, but directly posted his remarks online and begged other netizens for explanations. Isn't this ridiculous?
