What is the experimental principle of smog waterfall?

　　The experimental principle of smoke waterfall is that the upward movement of smoke is actually driven by hot air, because the space in the straight tube is relatively narrow and there is less hot air.

　　Introduction of experimental process

　　1. Experimental materials of smog waterfall: plastic bottles, paper and candles.

　　2. Drill a small hole in the upper part of the beverage bottle for later use.

　　3. Wrap the paper into a paper tube and insert it into the small hole.

　　4. Light the paper tube exposed outside the bottle and set it aside.

　　5, experimental phenomenon, smoke from the paper tube in the bottle, forming a waterfall.

　　6. Experimental principle When smoke enters the bottle, the temperature in the bottle rises and the air pressure in the bottle is lower than the outside air pressure, so the smoke presses down to form a waterfall.

　　7. So at this time, there are no completely burned smoke particles, which are denser than air, so they will fall and form a smoke waterfall.

　　summary

　　1. Smoke pours down like a waterfall from one end near the mouth of the cup. After extinguishing the flame, it is found that there is a yellow substance on the wall of the cup.

　　2. Experimental principle: The density of smoke after gathering is higher than that of air, and the temperature of the sinking paper mouth is higher, which makes the temperature in the cup rise.

　　3. The pressure in the cup is less than the external pressure, so the smoke falls downward, and the yellow substance on the cup wall is a carbonaceous substance that is not completely formed by combustion.