Where is the center of gravity of the tumbler?

This low center of gravity can improve stability and is not easy to fall or turn over.

The center of gravity of a "regular shape" object is its geometric center. The outside of the tumbler looks like an egg, but in order to improve its stability, the designer put heavy things on the bottom inside, such as cement, rice grains, sand and gravel.

Tumbler principle

Objects that are light on the top and heavy on the bottom are relatively stable, that is, the lower the center of gravity, the more stable it is. When the tumbler is in equilibrium in an upright state, the distance between the center of gravity and the contact point is the smallest, that is, the center of gravity is the lowest. After deviating from the equilibrium position, the center of gravity always rises. So the balance of this state is a stable balance. Therefore, no matter how the tumbler swings, it will not fall. Another example is the experiment of "rolling on a cone" that we saw in the Science and Technology Museum. Because of the shape of the cone and the shape of the tracks on both sides, its center of gravity is falling, but it seems to be rising, which does not conform to the facts in life. But this is just an illusion. Seeing its essence clearly, the center of gravity is lowered, so the lower the center of gravity, the more stable it is. In order to increase the stability of objects in life, we often increase the weight below, such as fan base, microphone bracket, bus stop sign and so on.

Using this feature, we can do many interesting experiments and explain some phenomena. If you can become a beetle, open a capsule and put a small ball in it, you can turn your head back and forth. We often put a box on the table a little, but it won't fall. This is because the box is close to one end of the table, which is the "center of gravity", so the box hangs but will not fall. Acrobats who walk a tightrope also hold the balance bar to lower their center of gravity and achieve balance.

Self-made method of tumbler: choose the packing box of spherical plastic Chinese medicine pills, which can be opened from the middle, just two hemispheres. Put a proper amount of plasticine or wet plasticine in one hemisphere to become the bottom of the tumbler, and stick a conical hat outside the other hemisphere to become the top of the tumbler. After the two hemispheres are buckled, draw a face and it is ready.

Because of its anti-rotation and anti-falling characteristics, the tumbler has been given the pronoun of being good at self-protection. There is a story: There was a great official in the Qing Dynasty, and there were many party member. Once, a self-proclaimed protege came to visit him and brought a big lacquer box. When he opened it, there were hundreds of glasses of different sizes. The protege said: "The soil in my hometown is easy to make this thing, and the skill is quite exquisite. It is specially designed to relieve boredom for adults. " The official accepted it, laughing to himself that the pupil was a bit silly. After the protected person left, the family came to see things and found that there was a note with the name on the back of each tumbler, and the biggest one was the name of the official. There is a piece of paper in the box, which reads: "A sharp head can drill, an empty stomach can bear it, a dignified crown, a dirty face and heart, it looks easy to fall, but it can't stand up." This sentence vividly depicts the image of a tumbler, which is stinging. The official was furious and let his men look closely, only to find that there was no such a protege.

There are many "tumbler" officials in ancient and modern times. There was a Feng Deyi in the Tang Dynasty who was very fond of him before his death. After committing a crime, his life story flourished with the Tang Dynasty. He is good at running the officialdom, playing tricks all day and becoming a "tumbler" who keeps his position and keeps his pet.