Life is full of science, and now everyone in society is inseparable from science, have you ever discovered the science around you? The car can not run without oil, with a ram's horn hammer nails more labor-saving, candles thrown in the water will float up, myopic people wear myopic glasses can see clearly, when burning firewood with a fan fan fire will be more vigorous, fire extinguishing can use carbon dioxide. There is never a lack of magical phenomena in life, all that is missing is a pair of eyes that are good at discovery.
There are many jugglers on the street, some put their hands into the hot room oil pot, the people who watch are terrified, some people hang in the air with a stick, making people wonder, and some magicians play you around with three cards, it seems that seeing is not necessarily true.
Today we will talk about these things, the three cards are based on the magic skill, although I know, but here will not be detailed, let's talk about the science of this. Magicians distract you with words and movements. This is also the main reason why magic can succeed, you carefully observe those famous magicians, his aura must attract you.
Let's talk about how to reach into a hot frying pan. First pour vinegar into the pan, and then add some oil to the vinegar, we all know that the density of oil is greater than vinegar, so the oil will float on the surface. When the ignition begins, a large part of the smell of vinegar is covered with oil. The boiling point of the oil is above 200 ° C, and the boiling point of the vinegar is only 60 ° C, so when the vinegar boils, the oil has not yet boiled, and the "oil pot" at this time looks like it is churning in fact only 60 ° C Of course, the hand will not be hot, do you understand this?
Ancient heroes or gods who fool people often use a particularly powerful skill, showing words on white paper. It is clearly a blank piece of paper that is baked on the fire and the words on it appear. The gods deceived people by saying that this must be the will of god. Do you know how to do it? If not, I will teach you to make this invisible ink, and if you travel back to ancient times, you will not be fooled, but you can also fool others in turn. First we take the appropriate sugar and mix with water, and when the sugar is completely melted in the water, what we need is ready. After writing and drying on a white paper with sugar water, when its water traces disappear, the words are invisible, and if you want to make it appear, you only need to bake it by the fire. Interested students, you can go to the experiment to try it out.
Next, I will talk about the principle, after the sugar water is dried, the water traces, handwriting, and images disappear. At this time, roast it with fire, the water in the sugar water evaporates, after the loss of water, the sugar is dehydrated and remains light brown, and the word naturally appears, how to know the principle? Use your brain to think about what other liquids can be used as invisible ink in addition to sugar water? In fact, we have a similar effect in chemistry, we can write on paper with colorless phenolphthalein solution, then the paper is colorless, if we are in soapy water (any liquid with a ph value greater than 7, of course, the larger the effect, the more obvious. ) and the words in red appear on the paper.
In both the chemistry and physics classes, an experiment was mentioned, that is, the famous fruit battery experiment, the teacher inserted several fruits with two different pieces of metal, connected the wires, and finally connected to the poles of the small electric lamp, and the magic happened. The small electric light actually came on! The teachers actually "generated electricity out of thin air", and the students are very familiar with this experiment, but have you ever thought about the principle?
In fact, the principle of this experiment is really very simple, fruit battery is a kind of battery that uses chemicals in fruit to react with metal sheets to generate electrical energy. The premise of the experiment is to have acidic substances, as well as two kinds of metal sheets with a large difference in activity, (so in fact, we can actually use carbonated drinks instead of fruits, and students can try.) Because the electrochemical activity of the two metal sheets is not the same, the more active side of the metal sheet can replace the hydrogen ions of the acidic substance, because a positive charge is generated, but it needs to be stable, so in the case of the composition of the primary battery, the free electrons maintain the stability of the system from the loop, so in this case, if the length of the loop changes, it will cause a change in the loop, and it will also cause a change in voltage. As soon as the voltage changes, there is electricity, so it is not that electricity is generated for no reason, but that the charge is transferred.
Therefore, there is never a shortage of scientific phenomena in life, and what is missing is only a pair of eyes that are good at discovery. We not only have to see, but also to do, experiment is an important part of scientific proof, but also an indispensable step of science, the conclusion is based on a large number of experimental data, it can be said that the experiment is the cornerstone of the scientific building. I am a very fond of experimenting, and I hope that my classmates will be as curious in life as I am. For me, the result of an experiment was like a skydiving, the body fell at a very high speed, and the heart was still in the clouds, and I really couldn't tell what it felt like...
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