2016年职称英语卫生类概括大意模拟试题
本文本站小编为大家送上最新的卫生类概括大意模拟试题,希望能帮助大家提高理解能力!
Volts from the Sky
Lightning has caused awe and wonder since old times. Although Benjamin Franklin demonstrated lightning as enormous electrical discharge more than 200 years ago, many puzzles still surround this powerful phenomenon.
Lightning is generated when electrical charges separate in rain clouds, though processes are still not fully understood. Typically, positive charges build at the cloud top, while the bottom becomes negatively charged. In most instances of cloud-to-ground lightning, the negatively charged lower portion of the cloud repels negatively charged particles on the ground s surfaces, making it become positively charged. The positive charge on the ground gathers at elevated points.
A flow of electrons begins between the cloud and earth. When the voltage charge becomes large enough, it breaks through the insulating barrier of air, and electrons zigzag earthward. We see the discharge as lightning.
Lightning can occur within a cloud, between clouds, or between clouds and the ground. The first variety, intra-cloud lightning, is the most frequent but is often hidden from our view. Cloud-to-ground lightning, making up about 20 percent of lightning discharges, is what we usually see. Lightning comes in several forms, including sheet, ribbon, and ball. Intra-cloud lightning can illuminate a cloud so it looks like a white sheet, hence its name. When cloud-to-ground lightning occurs during strong winds, they can shift the lightning channel sideways, so it looks like a ribbon. The average lightning strike is more than 3 miles long and can travel at a tenth of the speed of light. Ball lightning, the rarest and most mysterious form, derives its name from the small luminous ball that appears near the impact point, moves horizontally, and lasts for several seconds.
Thunder is generated by the tremendous heat released in a lightning discharge. Temperatures near the discharge can reach as high as 50,000°F within thousandths of a second. This sudden heating acts as an explosion, generating shock waves we hear as thunder.
About 2,000 thunderstorms are occurring in the world at any time, generating about 100 lighting strikes every second, or 8 million daily. Within the United States, lightning strikes are estimated at 20 million a year, or about 22,000 per day. You have a 1-in-600,000 chance of bring struck by lightning during your lifetime. Lightning can strike twice or more in the same spot. The Empire State Building in New York is struck by lightning about two dozen times annually.
You can measure how far you are from a lightning strike by counting the seconds between viewing the flash and hearing the bang, and then dividing by five. This approximates the mileage.
练习:1-4题的要求是,从第一个方框的六个选项A、B、C、D、E、F中选出四个选项为注明的'段落各配一个合适的小标题。5-8题的要求是,从第二个方框的六个选项A、B、C、D、E、F中选出四个选项完成每个句子。
1. Paragraphs 2 and 3
2. Paragraph 4
3. Paragraph 5
4. Paragraph 6
A Cloud-to-ground lightning occurring in the U.S.
B Types of lightning
C Cause of lightning
D Differences between thunder and thunderstorm
E Frequencies of thunderstorms occurring in the world and the U.S.
F Shock waves as thunder
5. In most cases of cloud-to-ground lightning, the ground s surface …
6. One form of lightning that … is ball lightning …
7. Cloud lightning looks like a ribbon when its lighting channel …
8. Although not fully understanding processes of lightning, man …
A occurs most infrequently.
B is shifted sideways by strong winds.
C is often hidden from our view.
D is equipped with a good knowledge of various forms of lightning .
E is estimated at 20 millions a year.
F is positively charged.
KEYS: C B F E F A B D
-
职称英语试题《综合C》词汇选项练习
Atruegreatmanwillneithertrampleonaworm,norsneaktoanemperpor.以下是小编为大家搜索整理的职称英语试题《综合C》词汇选项练习,希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生考试网!1.Formulatedin1823,theMonroeDoctrineassertedthattheAmeric...
-
2017职称英语考试通过技巧
由于外语学习的特殊性,英文基础较差者,应该现在就开始准备复习;有人认为距考试还有七八个月太早,考前2个月准备也不迟,这是种错误的想法。外语考试不是数理化或者本专业的业务考试,临阵磨枪,应付一下就能万事大吉,毕竟职称英语要求考生能认知5000-6000个单词,单纯从词...
-
职称英语真题卫生类A阅读理解
职称英语考试中,阅读理解能把握得怎么样,直接决定能不能及格。它是整个考试备考过程中最重要的一个环节。以下是小编整理的职称英语真题卫生类A阅读理解,供大家备考。职称英语真题卫生类A阅读理解1阅读理解ANewStrategytoOvercomeBreastCancer.Post-menopausal(绝...
-
2017年职称英语补全短文模拟题
多做题、多练习,才能知道自己的不足。以下是小编为大家搜索整理的2017年职称英语补全短文模拟题,希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生考试网!Likefinefood,goodwritingissomethingweapproachwithpleasureandenjoyfromthefirsttastetothel...