题型:阅读理解 题类:常考题 难易度:普通
黑龙江大庆实验中学2016-2017学年高一上学期英语期中考试试卷
You know that balloons must be kept away from sharp objects. They also needed to be kept away from flames. A fire can weaken the rubber and cause it to break. However, in this experiment you will find out how you can hold a balloon directly in a flame without breaking the balloon.
Materials needed:
● two round balloons not inflated(充气的)
● several matches
● water
Inflate one of the balloons and tie it. Place 1/4 cup of water in the other balloon, and then inflate it and tie it. Light a match and hold it under the first balloon. Allow the flame to touch the balloon. What happens? The balloon breaks, perhaps even before the flame touches it. Light another match. Hold it directly under the water in the second balloon. Allow the flame to touch the balloon. What happens to this balloon? It doesn't break.
Why does the balloon with no water break in the flame? The flame heats the rubber of both balloons. The rubber of the balloon without water becomes so hot that it becomes too weak to resist the pressure of the air inside the balloon. However, when the balloon with water in it is placed in the flame, the water takes in most of the heat from the flame. Then, the rubber of the balloon doesn't become very hot, it doesn't weaken, and the balloon doesn't break.
Water is a particularly good absorber(吸收者) of heat. It takes a lot of heat to change the temperature of water. On the other hand, when water cools, it gives off a great deal of heat. That's why areas near oceans or other large bodies of water don't get as cold in winter as areas at the same latitude(纬度) further inland.
Looking to have a rest after the working days?Check out to see if the following events are in your area!
Northside Festival Description: The music festival consists of artists, such as Sidney Gish and Orion Sun, free cake for everyone! If you're looking for a fresh festival with unique artists, look no further! Time: Saturday, June 9~10, from 12 pm to 6 pm Location: Baby's All Right, Brooklyn Tickets:$ 50 per person with no discount |
Solely Women Description: The William Ris Gallery is showing an exhibit all about what females meet in front of life! Check out the exhibit before it's closed after this weekend! Time: June 8~10, from 12 pm to 5 pm Location: William Ris Gallery at Jamesport Tickets: Free |
Broadway Commons Carnival Description: It's the season of carnival rides and food on a stick-yes, the carnival is still in town. With free admissions and lights to light up the sky, who wouldn't want to send their day off at Dreamland? Time: May 31~June 17, from 5 pm to 11 pm Location: Broadway Mall Tickets: Free carnival parking, admission and Victoria Circus shows |
Long Island's Festival Description: With exciting events ranging from beach concerts to parades, it's a large and impressive entertainment we can't wait for! You can also start your day with your family to have fun on the Long Beach boardwalk. Time: June 8~10, from 10 am to 11 pm Location: Long Beach Tickets:$ 80 per adult for the concert,a20% discount for children under18 |
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