题干

木块与小车向右做匀速直线运动,遇到一障碍物时,小车停下,木块从车上的a点滑至b点(如图甲),是因为木块具有____ ;木块能停在b点,说明木块在滑动过程中受到向____ (填“左”或“右”)的摩擦力作用.为测量摩擦力的大小,小明在障碍物上固定了弹簧测力计拉住木块,用手拉着小车向左运动(如图乙).则木块受到的摩擦力方向向____ (填“左”或“右”),大小是____ N.

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惯性 ,左 ,左 ,2.6 

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    There are many different voices on charity donations recently. Chen TianQiao, one of the Chinese billionaires, gave away $115 million to the California Institute of Technology (Caltech) to help promote brain research. Chen has been interested in the brain research, believing it can advance the industries of artificial intelligence and virtual reality. However, this huge donation has caused heated discussion among Chinese scholars and internet users.

    Many criticized him for giving money to a foreign university rather than domestic institutes for brain research, which are developing fast and are catching up with the US in just a few years. RaoYi, a biologist at Peking University, even said the donation was a typical mistake.

    Others, however, support his choice. They believe Caltech is a more reasonable choice compared with Chinese research Institutes. Caltech has a long history and has taken a leading position in biology, and therefore it produces more efficient results. What's more, the results of the research will benefit not only the Americans, but also the rest of the world.

    A similar controversial(有争议的)case started two years ago when Pan ShiYi, chairman of SOHO China, donated $15 million to Harvard University to help disadvantaged Chinese Students.

    Many believe that China is still far behind in management and use of donated money, and that as a result, Chinese donators are looking abroad. In comparison, Western countries like the US, which have a long history of donating money, have well-developed systems that use money efficiently. They can also provide full access for donors who want to track the use of the money. To get more donations, Chinese universities should be braver and more honest. They need self-reflection rather than envy.