It is urgent to give a lecture on popular science knowledge!

Why is a bottle full of water not easy to break?

There are two identical glass bottles, one is empty, the other is full of water, and at the same time it falls to the ground from the same height. Which bottle breaks easily? Generally speaking, heavy bottles break easily. But when the bottle is filled with water, the water in the bottle has another function, which can reduce the deformation of the bottle and make it difficult to break. Most of the broken glass bottles are caused by deformation. When the empty bottle falls to the ground, the pressure is constantly exerted on the bottle, and the bottle is deformed from the outside to the inside and finally breaks. The bottle is full of water. Because water is incompressible, the deformation is reduced and the bottle is not easy to break. The bottle is filled with water, and then the cap is tightened, so it is more difficult to break.

Have we inhaled the soda?

We suck soda through a straw, always thinking that it is our mouth that sucks soda up. Actually, it's not. It only sucks the air in the straw. As for soda, it is the atmosphere that presses it into the mouth. It turns out that after the air in the straw is sucked away, the soda in the tube is reduced by the air pressure, while the soda in the bottle (outside the straw) is at atmospheric pressure. These two pressures are not equal. If the atmospheric pressure is higher, soda will be pressed into your mouth. If the soda bottle is covered with a cork and a glass tube is inserted in the cork, you can suck soda from the glass tube once or twice at most, and you will never get soda from the bottle again. The reason is also very simple, because the atmosphere outside the bottle can't enter the soda bottle, and the atmosphere can't press the soda into the mouth. Can I still drink soda without unplugging the cork? Although it can't be sucked up, can it be blown up? Blowing air into the glass tube is one way. Blowing increases the gas in the bottle and increases the gas pressure in the bottle. When the pressure of the gas in the bottle increases, the soda will be squeezed out of the glass tube. At this time, as long as the mouth does not leave the glass tube, soda can be drunk. The more you blow into the bottle, the more the pressure increases, and you can drink soda smoothly. After drinking some soda, the volume of gas in the bottle becomes larger and the pressure decreases, so you can't drink soda. Blow again, and you can continue to drink soda.

Famous saying:

1. Only by obeying nature can we conquer nature.

-Darwin

2. Nature is a kind mother and a cruel butcher.

Hugo

People often treat the surrounding environment as a free commodity and spoil it at will without knowing how to cherish it.

Gan Harman

What the earth gives to all people is the essence of material, but what it finally gets from people is the garbage of these materials.

whitman

We should obey nature instead of forcing it.

-Escuman

Because of our invasion of nature, we have destroyed the beauty of natural landscape, natural dynamics and natural beauty.

Norman cousins

7. If you want to live a safe life, there are five essentials: first, purify the air; Second, we must clarify drinking water; Third, we should recycle ditches; Fourth, clean the house; Fifth, there should be plenty of sunshine.

-Nightingale