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    worse 由与环境有关可知.应是worse.形容词bad的比较级.意为“更糟糕 ,“the +比较级--.the +比较级-- 是固定结构.译为“越--.就越-- . 【查看更多】

     

    题目列表(包括答案和解析)

    如图所示，甲是探究“动能的大小与什么因素有关”的实验装置,实验中让同一钢球从斜面上不同的高度由静止滚下，碰到同一木块上．乙是探究“阻力对物体运动的影响”的实验装置，实验中让同一小车从斜面上相同的高度由静止滑下，在粗糙程度不同的水平面上运动．请回答下列问题：

    　　（1）甲实验的目的是探究钢球动能的大小与             的关系；实验时，它是通过观察            ，从而判断钢球动能的大小。
    　　（2）进行乙实验时，每一次都让同一小车从斜面上相同的高度由静止滑下，其目的是使小车在水平面运动的起始             相同；通过观察小车在粗糙程度不同的水平面上运动            来判断小车在不同的水平面受到            的大小．从而可以推理：如果运动的物体不受力，它将                。

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    阅读理解

    　　下面是一篇关于人口与环境的短文，你能从中受到什么启发呢?请阅读文章。然后回答问题。

    　　Pollution and Population

    　　The earth is our home．We must take good care of it．This means to keep the land，air and water clean．But pollution is a serious problem．To pollute

    means to make things dirty．Pollution appears in many forms．We can see it，smell it and drink it．pollution is beginning to do harm to our life．

    　　Man has been polluting the earth from the time he first made his fire，washing his clothes in the river and throwing his rubbish on the ground．Long，long ago，the problem was not so serious because there were not so many people．There are more and more people in the world．From last century，man had polluted the world more and more and the environment was getting worse and worse．

    　　Talking about pollution，we once only meant air pollution．It is true that air pollution is still the most dangerous Now，but it is only one kind of pollution.For example，by using poison，we have polluted the land and killed the animals．By putting dirty water into rivers and lakes，we have polluted Our drinking water and killed the fish and so on．

    　　The more people there are，the more rubbish there will be．If we want to stop pollution，we should keep the population from growing too fast．

    (1)

    What can we do to take care of the earth?

    (2)

    Is pollution harmful to our life?

    (3)

    When has man been polluting the earth?

    (4)

    Do you think if there are too many people in the world?

    (5)

    What will we do to protect the environment?

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    阅读理解

    　　Zhang Li lies in bed sadly．The 24-year-old young man lost his right leg because of a blood disease．The doctor said that his 10 years of smoking had caused the disease．“I began to smoke when I was in Junior 3．It made me feel like a man and I thought it looked cool．Now I know I was really wrong．” said Zhang．

    　　It is a mistake many teenagers make．It is said that about 40 million of the country’s young people between 13 and 18 have tried smoking．Nearly 68 percent of teenager smokers smoked their first one before the age of 13．Those who live in big cities started even earlier．Many teenagers see people smoking in the movies．But in real life, stars like Jackie Chan think smoking is a bad thing．In fact, smoking is one of the top killers in China．Each year one million people die from smoking-related(与吸烟有关的)diseases．Smoking causes illnesses like lung cancer and heart disease．

    　　Doctors say that the younger a person starts smoking, the worse it will be．If a person starts smoking as a teenager, he or she may live twenty-two years less than non-smokers．

    (1)

    What kind of disease did smoking cause for Zhang Li?

    [　　]

    A．

    Lung cancer．

    B．

    Blood disease．

    C．

    Heart disease．

    (2)

    From the passage, we know Zhang Li started to smoke when he was ________ years old．

    [　　]

    A．

    13

    B．

    14

    C．

    18

    (3)

    The city’s young people ________．

    [　　]

    A．

    knew that smoking was a bad thing

    B．

    tried smoking when they were in Junior 3

    C．

    started smoking earlier than those in the country

    (4)

    Which of the following is NOT TRUE according to the passage?

    [　　]

    A．

    Zhang Li had a disease and lost his left leg．

    B．

    Smoking may cause many kinds of diseases．

    C．

    Smoking may make you have a shorter life．

    (5)

    What does the underlined word “non-smokers ” mean in English?

    [　　]

    A．

    People who like smoking．

    B．

    People who smoke．

    C．

    People who don’t smoke．

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    在物理学中，磁场的强弱用磁感应强度（用字母B表示，国际单位是特斯拉，符号是T）来表示，磁感线越密的地方，磁场越强，磁感应强度B越大.

    （1）在图20中，甲为某磁极附近磁感线的方向和分布的示意图，由图可知，该磁极为 ▲ 极，若在l处放置一个小磁针，当小磁针静止时，其指向应是图乙中的  ▲   .
    （2）磁敏电阻阻值的大小随磁场的强弱变化而变，图丁是某磁敏电阻R的阻值随磁感应强度B变化的图象，据图线可知，磁敏电阻的阻值随磁感应强度B的增大而▲ ．图线没有过坐标原点，说明  ▲  .
    （3）王强设计了一个可以测量该磁敏电阻R的电路如图丙所示，（其中磁敏电阻所处的磁场未画出）．将该磁敏电阻R放置在磁场中的位置某处，测出电阻后，利用R—B特性曲线可以读出相应的磁感应强度.
    ①在图甲磁场中1处，测得的数据如图20表中所示，则该磁敏电阻的测量值为 ▲ Ω. 
    ②根据该磁敏电阻的R-B特性曲线可知，1处的磁感应强度为   ▲    T.
    ③在实验过程中，仅将磁敏电阻从1处移至2处，其它条件不变，那么电流表的示数
    ▲   （填“增大”、“减小”或“不变”）.
    ④依据上述方法获得的磁感应强度B的测量值与该点实际值存在不小的误差，为尽可能准确反映空间某点磁场的强弱，你认为在选择磁敏电阻时应注意什么问题？

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    Zhang Li lies in bed sadly. The 24-year-old young man lost his right leg because of a blood disease. The doctor said that his 10 years of smoking had caused the disease. “I began to smoke when I was in Junior 3. It made me feel like a man and I thought it looked cool. Now I know I was really wrong.” said Zhang.

    It is a mistake many teenagers make. It is said that about 40 million of the country’s young people between 13 and 18 have tried smoking. Nearly 68 percent of teenager smokers smoked their first one before the age of 13. Those who live in big cities started even earlier. Many teenagers see people smoking in the movies. But in real life, stars like Jackie Chan think smoking is a bad thing. In fact, smoking is one of the top killers in China. Each year one million people die from smoking-related(与吸烟有关的)diseases. Smoking causes illnesses like lung cancer and heart disease.

    Doctors say that the younger a person starts smoking, the worse it will be. If a person starts smoking as a teenager, he or she may live twenty-two years less than non-smokers.

    1.What kind of disease did smoking cause for Zhang Li?

    A. Lung cancer. B. Blood disease.   C. Heart disease.

    2.From the passage, we know Zhang Li started to smoke when he was      years old.

    A. 13   B. 14   C. 18

    3.The city’s young people .

    A. knew that smoking was a bad thing

    B. tried smoking when they were in Junior 3

    C. started smoking earlier than those in the country

    4.Which of the following is NOT TRUE according to the passage?

    A. Zhang Li had a disease and lost his left leg.

    B. Smoking may cause many kinds of diseases.

    C. Smoking may make you have a shorter life.

    5.What does the underlined word “non-smokers ” mean in English?

    A. People who like smoking.

    B. People who smoke.

    C. People who don’t smoke.

     

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