题干

进入21世纪,国际上掀起了新一轮的火星探测热.在太阳系几大行星中,火星与地球最为相似.探测火星将有利于寻找地球之外适合人类居住的第二家园.回答下题:

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同类题2

    In a famous story, a young boy called Ali Baba says “Open Sesame” and a door to treasures is opened before him. Ma Yun drew inspiration from this and founded Alibaba.com.
    Over 14 years, Alibaba.com has become China's largest e-commerce (电子商务) website. E-commerce is the a____  of buying and selling goods and services and doing other business activities using a computer and the Internet. However, the founder chose to leave and to discover new areas of business. On May 28, Ma became chairman of Cainiao Network Technology Co., Ltd.The company will set up China Smart Logistics (物流) Network. Its goal is to deliver packages (运送包裹) to people anywhere in the country w____ 24 hours.
    The 48-year-old businessman, who is short and thin and often wears oversized suits, always had he courage to dream big and try new things.
Ma got the idea or starting a business career in 1995. He was then working for a US trading company as a translator, when he was introduced to the Internet. He s____  the word "beer" and saw that no data came up about Chinese products(产品).
    Ma had an idea: why not build a large Internet market to connect(连接)consumers and companies from all over the world and do business o____ ?That is how Alibaba began. His company grew quickly. But that doesn't mean e____  went well. Alibaba had a difficult time in 2000, when many Internet companies failed. Ma was successful because he m____ to attract investment(投资)in his company.
   But there is a deeper r____ for Ma's success: his attitude. "You deserve (值得) to live your dream," said. "Everyone thought I was daydreaming when I started. But the most important thing is that we believed in our dream from day one, to today and tomorrow Of course we made many mistakes, but we never gave up hope."

同类题5

小明的爸爸新买了一辆小汽车,如图所示,小明坐着这辆汽车匀速行驶144 km,用时2h,消耗汽油9kg,其发动机的功率为23kW.请运用所学的知识解答下列问题.(汽油的热值为4.6×107J/kg)

(1)汽车“发动机”通常都是以汽油或柴油为燃料的,汽油、柴油都属于____ (可再生/不可再生)能源;汽车“发动机”一般需要用水来作冷却剂,这是利用了水的____ 的属性;

(2)汽车在高度行驶过程中发生碰撞,车身停止运动,而乘员由于具有____ 会继续向前运动,此时弹性很强的安全带被拉伸而获得____ 能;安全带做得宽大的目的是____ 

(3)汽车在高度行驶过程中一旦发生碰撞,车身停止,而乘员则会继续向前与车身撞击,甚至能把挡风玻璃撞碎而飞出车外.在发生交通事故时,安全带能对人体起到缓冲的作用,防止出现二次伤害.在发生严重撞击时,方向盘等处的车载气囊会自动充气弹出,在人体接触到安全气囊时,安全气囊通过气囊表面的气孔开始排气,从而起到缓冲作用,减轻身体所受冲击力,大大减小伤害.

对于短文中提到的“缓冲”,文静同学提出了自己的猜想:安全带和安全气囊增加人与碰撞物间的接触时间,从而大大减小撞击力.物理兴趣小组的同学共同设计了如下实验方案:在两个相同的玻璃槽中堆放不同厚度的面粉,从相同的高度先后落下同一只鸡蛋.落在面粉厚度大的槽中,留下较深的坑,鸡蛋完好无损;落在面粉厚度较小槽中,鸡蛋破裂.实验中通过比较____ 来比较撞击时间的长短,根据实验可以验证文静同学的猜想是____ (正确/错误)的;请列举上述“缓冲”物理知识在生活中应用的一个实例:____