Question

Study carefully both the figure and the passage and answer the following questions:

　　If a plane is standing on the ground, the air pressure on all its different parts is the same． This air pressure is increased or reduced when the plane moves．

　　There are four forces which act on a plane as it flies through the air． The weight of the plane, because of the earth’s gravitation, a drawing force towards its centre, always pulls the plane downward． Drag prevents and delays the forward movement of the plane ． Drag is caused by the opposite force the airframe or the body of the plane offers as it moves through the air and by the whirling or turning movements of air which form near edges of the lifting surfaces of the plane． Weight and drag are successfully defeated by thrust, a forceful forward movement, and lift, an upward air pressure on the wings of the plane． Thrust is provided or supplied by the engines which drive the plane forward． As the plane moves forward, the air flowing over the wings produces lift to raise the plane off the ground , and keep it in the air．

　　The upper surface of a plane wing is made a rounded line like thisÉ at the leading edge while the under surface is almost flat to give the highest lift/drag ratio(such as 2:1 or 3:2．) ． A rounded nose smoothly rounded top and a sharp tail is known as aerofoil （翼型）shape or the shape of the wings , the fin or tail plane of a plane． This particular shape makes air flow faster and farther over the wing than under it． Pressure above the wing is reduced and the wing is given lift． The amount of lift increases with the speed of the plane．

1． When the plane is standing on the ground the pressure on its upper surface is　　　　 that of its under surface．

A． the same as B． different from C． larger than D． smaller than

2． When the plane moves , the air pressure on its body is 　　　　 ．

A． the same　　 B． changing C． unchanging D． neither A nor B nor C

3． When the plane is flying, the four forces are acting on it in 　　　　 ．

A． the same direction　　　　B． two different directions

C． three different directions D． four different directions

4． The backward force acting on the flying plane is 　　　　 ．

A． the earth's gravitation B． drag C． lift D． thrust

5． In the picture, A, B, C, D stand for　　　　 ．

A． the earth's gravitation, drag, lift, thrust

B． drag, lift, thrust, the earth's gravitation

C． lift, thrust, the earth’s gravitation, drag

D． thrust, the earth’s gravitation, drag, lift

6． Drag is the opposite force of 　　　　　　 ．

A． lift B． weight C． thrust D． whirling movements

7．　　 seems the most important of the four forces in making the plane take off and fly through the air．

A． lift B． weight C． thrust　　D． the earth’s gravitation

8． Part M in the picture is called the　　 edge of the plane wing．

A． leading B． rounded C． sharp　　D． upper

9． Aerofoil shape includes part　　　　 and part　　　　 in the picture．

A． M , N B． N , S C． S , D D． D , M

10． Which of the following statements is TRUE?

A． The faster the plane flies the easier it rises．

B． The higher Force D is the faster the plane goes up．

C． The stronger Force C is the faster the plane flies．

D． The sharp leading edge of the wing increases the air flow over it．

Answer 1

答案：A;B;D;B;D;C;C;A;B;A
解析：

此篇较难，因为生疏词汇较多，必须克服重重干扰，才能完成此题所有10个小题；其中不乏难题，如：第10小题，其问题10．Which of the following statements is TRUE?与其正确选项A． The faster the plane flies the easier it rises． 之和是最后一段The amount of lift increases with the speed of the plane．的改写与归纳。但是能不能改写或者归纳出正确选项，要依靠平时的大量实践，考场一分钟，平时三年功。

提示：

话题：阅读“物理话题”技巧。重点：细节捕捉、审读图片。