The surprising experiment I am about to describe proves that air is all around you and that it proves down upon you. Air pressure is a wonderful force. When you swim underwater, you can feel water push down your body. The air all around you does the same. However, your body is so used to it that you do not notice this. The pressure is caused by a layer of air called the atmosphere. This layer surrounds the Earth, extending to about five kilometers above the Earth’s surface.
The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now foe the experiment!
What you need
?A hard-boiled egg without the shell
?A bottle with a neck slightly smaller than the egg
?A piece of paper
?A match
Metheod
1) Check that the paper will sit firmly on the neck of the bottle.
2) Tear the paper into strips and put the strips into the bottle.
3) Light the paper by dropping a burning match into the bottle.
4) Quickly sit the egg on the neck of the bottle.
Result
A.stonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.
Why it happened
A.s the paper burns, it needs oxygen and uses up the oxygen (air) in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! The proves that air is all around and that it is pressing down on it.
60. Why is there the need to take care when you are doing the experiment?
A. The bottle could break.
B. You need to light the paper with a match.
C. The egg needs to be shelled.
D. The egg has to be perfectly placed on the neck of the bottle.
[单选题]I am [regretful]about what has happened.A.sorryB.disappointedC.shamefulD.di
[问答题]I am writing this letter to complain about the service in your hotel .
[问答题]I am writing this letter to complain about the service in your hotel.
[单选题]I am [optimistic]about the next round of talk in the Middle East.A.joyfulB.
[主观题]A.fter the experiment, we willtalk about our observation. (对画线部分提问)_____will you____ after the experiment?
[单选题]I prefer chicken to fish because I am worried about accidentallyswallowing
[单选题]The scientistswanted to keep people _____about the breakthrough in their ex
[单选题]B.I am a writer. I spend a great deal of my time thinking about the power of language—the way it can evoke(唤起) an emotion, a visual image, a complex idea, or a simple truth. Language is the tool of my trade. And I use them all—all the Englishes I gre
[单选题]In Henry's experiment,the galvanometer indicated a voltage when______.A. the coil was connected to a batteryB. the coil was disconnected to a batteryC. neither A nor BD. both A and B
[单选题]22.I am in _________ .A. Grade OneB. eightC. my friendD. Class One