Before going outside in the morning, many of us check a window thermometerfor th

Before going outside in the morning, many of us checka window thermometer(温度计)for the temperature. This helps us decidewhat to wear.    1.    We wantour food to be a certain coldness in the refrigerator. We want it a certainhotness in the oven. If we don’t feel well, we use a thermometer to see if wehave a fever. We keep our rooms a certain warmth in the winter and a certaincoolness in the summer.

Not all the thermometers use the same system tomeasure temperature. We use a system called the Fahrenheit scale. But mostother countries use the Centigrade scale.

Both systems use the freezing and boiling points ofwater as their guide.    2.   

The most common kind of thermometer is made withmercury(水银)inside a clear glass tube. As mercury (orany other liquid) becomes hot, it expands. As it gets colder, it contracts.That is why on hot days the mercury line is high in the glass tube.    3.  

First. Take a clear glass juice bottle that has a cap;fill the bottle with coloured water. Tap a hole in the center of the cap usinga hammer and thick nail. Put the cap on the jar. Then stick a plastic straw(吸管) through the nail hole.

   4.   

Finally. Place a white card on the outside of thebottle and behind the straw. Now you can see the water level easily.

   5.   

As the temperature goes down, the water will contract,and the level in the straw will come down. Perhaps you will want to keep arecord of the water level in the straw each morning for a week.

A．Thermometersmeasure temperature, by using materials that change in the same way when theyare heated or cooled.

B．We use anddepend on thermometers to measure the temperature of many other things in ourdaily lives.

C．Take wax (youmay use an old candle if you have one) and melt some of it right where the strawis struck into the cap to seal (把……粘住) themtogether.

D．The waterwill rise in the straw. As the temperature of the air goes up, the water willexpand and rise even higher.

E．They label these indifferent ways. On the Fahrenheit scale water freezes at 32 degrees and boilsat 212 degrees. On the Celsius scale water freezes at 0 degrees and boils at100 degrees.

F．Now that you know thisrule you can make a thermometer of your own that will work.

G．People use thermometerswhich are made by themselves when travelling around the world.

试题答案

【答案】

1.B

2.E

3.F

4.C

5.D 

【解析】

试题