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    精英家教网 > 初中英语 > 题目详情
    Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren’t very smooth (光滑的) rub together to make heat energy. The faster you rub two things together, the more friction you can make. Let’s discover friction!

    WHAT YOU’LL NEED:
    ★Soap                ★Water           ★Your hands
    WHAT TO DO:
    ★Make sure your hands are dry.
    ★Rub your hands together until you feel the heat of your hands.
    ★Now, use soap and water to get your hands very slippery (滑的).
    ★Try to make friction happen while your hands are slippery.
    ★Please write down what has happened.
    LET’S TALK!
    Friction is an energy that happens when two things rub together. When friction happens, it makes heat! When your hands are slippery, they won’t make very much friction and your hands won’t get so hot.
    DID YOU KNOW?
    ★Friction happens when you stop your fast running bike.
    ★Ancient people made fires by rubbing two pieces of wood together. Friction happened though they didn’t know it. ___  __?         Friction is everywhere. Have you ever noticed situations where friction is happening? If not, ask your parents to take you out in a car. If it is not hot, touch the tires (轮胎) of the car before and after a short drive to see how much warmer they get from friction.
    小题1:You’d better make your hands ______ to get heat when you rub them.
    A. slippery                 B. dry                  C. wet    
    小题2:The word “friction” in the first paragraph means “______”.
    A. 摩擦                     B. 震动                 C. 膨胀 
    小题3:We can know from the passage that it’s a ______ experiment.
    A. physics                  B. chemistry                C. biology
    小题4:The topic of the last column (栏目) is ______
    A. THINK IT OVER!           B. WHAT HAPPENED?       C. WORK WITH PARENTS.
    小题5:The main idea of the passage is ______.
    A. how to discover friction     B. how to rub your hands       C. how to make fires by rubbing   

    小题1:B
    小题2:A
    小题3:A
    小题4:C
    小题5:A

    试题分析：本文是介绍摩擦是怎么产生的，摩擦产生的条件，摩擦产生了什么能量，以及日常生活中一些跟摩擦有关系的现象。
    小题1:细节理解题。slippery滑的，dry干燥的，wet湿的，根据原文Make sure your hands are dry.Rub your hands together until you feel the heat of your hands.要先确定你的手是干燥的，然后把两个手放在一起摩擦直到你感觉到手热。故选B。
    小题2:词义猜测题。根据原文Friction happens when two things that aren’t very smooth rub together to make heat energy.当两个不光滑的东西搓在一起产生热量，就是摩擦。故选A。
    小题3:细节理解题。通过阅读可以知道摩擦是一种物理反应。故选A。
    小题4:细节理解题。根据原文If not, ask your parents to take you out in a car.可知主题是跟父母一起共事，故选C。
    小题5:细节理解题。根据原文Let’s discover friction!可知文章的主题是如何产生摩擦。故选A。
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