評論
打印
The Invisible Hand
無形的力量
A: What's going on?
A:發生什么事了？
B: Check out the setup, Yaoyao.
B:瑤瑤，看一下都有些什么設備吧！
A: A stove, an empty aluminum soda can, kitchen tongs, and a saucepan. Are you experimenting with a new recipe?
A:火爐，鋁制的的易拉罐，餐鉗和平底鍋。你是在做一個新的食譜嗎？
B:No, I'm experimenting with air pressure.
B:不是的，我是在做一個關于氣壓的實驗。
A:How?
A:怎么做？
B:First, I will put about a tablespoon of water in the soda can, and a little cold water in the saucepan. Now, I will heat the water in the soda can on the stove until it boils.
B:我先在易拉罐里加入約一湯匙的水，在平底鍋里加少許冷水。接著，將易拉罐放在火爐上加熱至其沸騰。
A: There steam coming out of the can.
A:這樣水蒸汽就從罐子里冒出來了。
B: Good! Now watch, i will pick up the can with a kitchen tongs like this and put it face down in the cold water in the pan. Ready?
B:對了！現在，我要用餐鉗像這樣將易拉罐夾起來，并將其正面放在有冷水的平底鍋里。準備好了嗎？
A:Ready!
A:準備好了！
B:Here goes!
B:看看會發生什么吧！
A: Wow, the can collapse like with being crushed down by an invisible hand.
A:哇噢，易拉罐碎了！就像被一只無形的手給壓碎的！
B: When the water in the can boiled, the water vapor pushed all the air out of the can. And when I flipped the can and put it in the pan, the cold water cooled the vapor, making it condense.
B:因為在（易拉罐里的）水沸騰時，罐子里的所有空氣都被水蒸汽排出。所以當我將罐子翻轉過來放在平底鍋里時，（鍋里的）冷水將水蒸汽冷卻、凝結。
A:Which left the can empty inside, allowing the pressure of the air outside the can to crush it.
A：這就使得易拉罐內部變空，從而讓外面的氣壓將其粉碎。
B: Exactly. Normal air pressure is about 15 pounds per square inch. Since the can was about three inches high and two inches wide, the air pressure on it was 15 pounds per six inches, or ninety pounds of air pressure used to crush the can.
B：非常正確！正常的氣壓大約是每平方英寸15磅。由于易拉罐大約是3英寸高、2英寸寬，它周圍的氣壓就是6平方英寸15磅，即每平方英寸90磅，從而將易拉罐粉碎。
A: Very interesting!
A:太有意思了！
