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  • General

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  • 项目:矢量

    Vector Project
    ::矢量项目

    In 2015, about 140.43 billion gallons of gasoline were consumed in the United States, a daily average of about 384.74 million gallons (or about 9.16 million barrels per day). (Source: U.S. Energy Information Administration,  )
    ::2015年,美国消费了约140.43亿加仑汽油,每天平均约384.74亿加仑(即每天约916万桶)。 (资料来源:美国能源信息管理局,......)

    1. Crude oil is sold in barrels of 42 gallons each. How many barrels are used each year?
      ::原油每桶销售42加仑,每年使用多少桶?
    2. If one barrel of oil begins rolling down a hill at a 10° angle, and the only force acting on it is gravity with a force of 500 N, what is the work done by the force of gravity after the barrel has rolled 150 meters?
      ::如果一桶石油开始从10度角向山上滚下, 而上面的唯一力量是500N的重力, 那么在桶子滚动150米后, 重力做了什么?
    3. How much force will a man use if he is dragging a barrel at constant speed at a 25° angle with the ground? 
      ::一个人要用多少武力 才能以固定的速度 以25度的角度拖着桶子 和地面一起走下去?
    4. A warehouse is storing 150 barrels of the crude oil, with each weighing about 300 pounds, when an earthquake occurs. The barrels tip over against the wall at an angle of 49°. What is the magnitude of the horizontal force against the wall? If the wall was built to withstand 30,000 lbs of force, what is the container angle that will cause the wall to collapse?
      ::当地震发生时,一个仓库储存着150桶原油,每桶重约300磅。桶倒在墙上,角度为49度。 水平力量对墙的强度是多少?如果建造墙是为了承受3万磅的强力,那么导致墙倒塌的集装箱角度是什么?