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    B Every object has weight. But the center of its weight is not always in the middle of the object. If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity is high. But if the bottom is heavier, it won’t fall easily. Then we say that its center of gravity is low. Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above the line of its bottom (AB). Now look at the second picture. There are some heavy things in the bottom of this box. It will not fall, because its center of gravity is above its bottom. 34. Box will not fall. A. B. C. D. 35. The main idea of the passage is . A. why things fall over B. a low center of gravity C. a high center of gravity D. that everything has weight 【查看更多】

     

    题目列表(包括答案和解析)

    Every object has weight. But the center of its weight is not always in the middle of the object. If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity is high. But if the bottom is heavier, it won’t fall easily. Then we say that its center of gravity is low.
    Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above the line of its bottom (AB).
    Now look at the second picture. There is some heavy iron in the bottom of this box. It will not fall, because its center of gravity is above its bottom.

    【小题1】If the bottom of an object is ______ its top, it will fall over easily.

    A．lighter thanB．heavier thanC．no heavier than　　D．as heavy as
    【小题2】Please point out which box will not fall.

    【小题3】The main idea of the passage is _________.
    A．why things fall over　　　　B．a low center of gravity
    C．a high center of gravity　　D．that everything has weight

    查看答案和解析>>

    Every object has weight. But the center of its weight is not always in the middle of the object. If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity is high. But if the bottom is heavier, it won’t fall easily. Then we say that its center of gravity is low.

    Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above the line of its bottom (AB).

    Now look at the second picture. There is some heavy iron in the bottom of this box. It will not fall, because its center of gravity is above its bottom.

    1.If the bottom of an object is ______ its top, it will fall over easily.

    A. lighter than　　 B. heavier than　　 C. no heavier than　　  D. as heavy as

    2.Please point out which box will not fall.

    3.The main idea of the passage is _________.

    A. why things fall over　　　　         B. a low center of gravity

    C. a high center of gravity　　             D. that everything has weight

     

    查看答案和解析>>

    Every object has weight. But the center of its weight is not always in the middle of the object. If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity is high. But if the bottom is heavier, it won’t fall easily. Then we say that its center of gravity is low.
    Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above the line of its bottom (AB).
    Now look at the second picture. There is some heavy iron in the bottom of this box. It will not fall, because its center of gravity is above its bottom.

    小题1:If the bottom of an object is ______ its top, it will fall over easily.
    A．lighter thanB．heavier thanC．no heavier than　　D．as heavy as
    小题2:Please point out which box will not fall.

    小题3:The main idea of the passage is _________.
    A．why things fall over　　　　B．a low center of gravity
    C．a high center of gravity　　D．that everything has weight

    查看答案和解析>>

    阅读理解
         Every object has weight. But the center of its weight is not always in the middle of the object. If the
    top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity(重力)
    is high. But if the bottom is heavier, it won't fall easily. Then we say that its center of gravity is low.
         Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above
    the line of its bottom (AB).
         Now look at the second picture. There are some heavy things in the bottom of this box. It will not fall,
    because its center of gravity is above its bottom.
    1. Box _____________will not fall..

    2. The main idea of the passage is _________.
    A. why things fall over  
    B. a low center of gravity
    C. a high center of gravity
    D. that everything has weight

    查看答案和解析>>

    阅读理解

    　　Every object has weight. But the center of its weight is not always in the middle of the object, If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity（引力）is high. But if the bottom is heavier, it won't fall easily. Then we say that its center of gravity is low.

    　　Look at the first picture, lifts empty box must fall over, bemuse its center of gravity (C) is not above the line of its bottom (AB).

    　　Now look at the second picture. There is some heavy iron at the bottom of this box. It will not fall, because its center of gravity is above its bottom.

    (1) Please point out which box will not fall?

    (2) From the passage, we can infer that the Leaning Tower of Pisa does not fall is because_______.

    [　　]

    A．the top of the tower is heavier than its bottom

    B．the bottom of the tower is not heavier than its top

    C．its center of the gravity is still above the line of its bottom

    D．its center of the gravity is not above the line of its bottom

    (3) If an object has a low center of gravity, _______.

    [　　]

    A．it won't fall

    B．it won't fall easily

    C．it is certain to fall over

    D．its top must be heavier

    (4) Which of the following is TRUE according to the passage?

    [　　]

    A．The center of the weight is always in the middle of the object

    B．The center of the weight is always on the object

    C．The center of gravity is not always in the middle of the object

    D．The center of the gravity is always high

    (5) The passage is mainly about _______.

    [　　]

    A．why things fall over

    B．a low center of gravity

    C．a high center of gravity

    D．that everything has weight

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