The principle of expansion when heated and contraction when cooled is used, which means that an object will expand when heated and contract when cooled. In this way, there is a gap between the bottle cap and the bottle body, which is easier to open.

safety tip: this operation has great safety risks, so please use it with caution. At the moment of thermal expansion, the bottle cap may suddenly fly out. At this time, if you hit someone, you will be easily injured, so the bottle mouth should not be pointed at people. Extended information

As the weather gets warmer, people who like to drink beer will be happy. But what if I can't find the bottle opener at the moment? Use chopsticks, a lighter to pry, bite with your teeth, or put the mouth of a beer bottle on the table and pat it open with your palm?

in the video, a foreign man named Keith Laidlaw folds a piece of A4 white paper in half five times in the kitchen to form a simple hard strip-a white paper bottle opener.

Then, after he folded the hard strip in half with his right hand, he used the folded angular part to be close to the sawtooth below the beer bottle cap, and his left hand gripped the neck of the beer bottle tightly, and the second joint of his left thumb pressed against the hard strip. When his right hand was forced to tilt, the beer cap was easily opened. The whole bottle opening process only takes about 21 seconds.

The reporter asked Zhou Jianlin, a volunteer who lives at No.18, New Village of Nanping Tongyuanju, to verify.

The reporter noticed that the edges and corners of A4 paper were hard after being folded in half for five times. After being used to pry the bottle cap several times, the edges and corners are worn out, but the bottle cap does not move; The second time, Zhou Jianlin folded A4 paper in half for 1 times, which showed signs of loosening when he pried it, but it was still unsuccessful. For the third time, he pried the six-folded strip back and forth around the bottle cap, and the bottle cap was finally opened after 5 minutes.

34-year-old Su Can has been engaged in catering for more than ten years, and he knows the common methods of opening beer bottles like the back of his hand. He once saw a man holding a beer bottle in his left hand, holding the bottle cap with five fingers in his right hand, and he could forcefully open the beer cap with his bare hands with a tug. The trick is that the strength of the fingers should be very strong, which ordinary people can't do.

two years ago, he saw a Guangdong guest shaking the beer bottle vigorously, grabbing the bottle neck with his left hand, hanging the wine in the air, and slapping the bottom of the bottle with his right hand, and the bottle cap was immediately opened. The guest explained that after shaking it gently, the carbon dioxide gas in the bottle will gather at the mouth of the bottle and pat the bottom hard. The wine in the bottle will bear the carbon dioxide and push the cap out with air pressure, but it will take countless exercises and ordinary people should use it with caution.

Always be careful when opening beer bottles like this

Yang Ke, a graduate student from the School of Physics of Southwest University, said that most methods of opening beer bottles use the lever principle, and the key is to find a suitable fulcrum and use moderate force. For example, using chopsticks or cardboard to open the lid is the same principle. "The closer the fulcrum is to the bottle cap, the easier it is to open the beer bottle. In addition, the lever itself should be hard enough."

Dr. Wang from the emergency department of Chongqing Armed Police Corps Hospital reminded that the safest and most effective way to open beer bottle caps is to use bottle openers, and other common bottle opening methods have certain risks.

For example, you may become a victim of cracked teeth if you often bite open the bottle cap with your teeth. Use the narrow edge at the bottom of the lighter to hold the sawtooth of the bottle cap, hold the bottle mouth with the other hand, and pry the bottle cap with your finger as a fulcrum. If you use excessive force, you may break the lighter and scratch your hand. The hazards such as opening the bottle cap with chopsticks and tapping the bottle cap against the edge of the table are similar.

In addition, each hand holds a bottle of beer. When the bottle mouth is opposite, the serrations of the two bottle caps are engaged with each other, and the two hands are forced upward and downward respectively to pry the bottle caps open. If any hand does not hold the bottle firmly or the strength is not enough, the beer bottle is easy to slide and break, and the fragments are in danger of scratching people. (Reporter Ruta's photo report)

Reference: People's Daily Online-Can a piece of white paper pry open the bottle cap of beer? This is really there!