题干

为了研究合力和分力的大小,甲乙两个同学做了如下实验,甲同学用拇指把栓校园卫士牌的轻质细绳用两手拉直,乙同学用一个手指轻轻一推,如图所示.关于这个实验,以下说法错误的是(   )

A:甲同学对细绳的拉力的合力与乙同学对细绳的推力大小相等

B:根据力的合成与分解原理可知,乙同学只要轻轻用力沿着同绳垂直的方向推细绳,细绳就会发生弯曲

C:根据功能原理可知,乙同学要想推动细绳,必须用较大的力对细绳做功,甲同学的手才能彼此靠近使细绳弯曲

D:根据实践经验可知,合力可以小于分力

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答案(点此获取答案解析)

C

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阅读理解

    Why do you go to the library? For books, yes--but you like books because they tell stories. You hope to get lost in a story or be transported into someone else's life. At one type of library, you can do just that--even though there's not a single book.

    At a Human Library, instead of books, you can “borrow” people. Individuals volunteer as human “books” and participants in the event can “read” the book--meaning they would have a one-on-one conversation with the volunteer and share in a dialogue about that individual's experience. “Books” are volunteers from all walks of life who have experienced discrimination (歧视) based on race, religion, class, gender identity, age, lifestyle choices, disability and other aspects of their life

    For a certain amount of time, you can ask them questions and listen to their stories, which are as fascinating and as attractive as any you can find in a book. Many of the stories have to do with some kind of stereotype. You can speak with a refugee (难民), a soldier suffering from PTSD, a homeless person or a woman living with HIV. The Human Library encourages people to challenge their own long-held beliefs-to truly get to know, and learn from someone they might otherwise make a quick judgment about.

    According to its website, the Human Library is “a place where difficult questions are expected, appreciated and answered.” It provides the opportunity for the community to share and understand the experiences of others in their community.

    The Human Library Organization came to be in Copenhagen, Denmark in 2000. Ronni Abergel, his brother Dany, and some colleagues hosted a four-day event during a major Northern European festival, hoping to raise awareness about violence among youth. After the success of this event, Abergel founded the Human Library Organization, which has been growing ever since.

    Though there are a few permanent human libraries, most aren't places at all, but events. Though many do take place at physical libraries, you don't need a library card—anyone can come and be part of the experience. There have been human library events all over the globe, in universities and in pubs, from Chicago to Tunis to Edinburgh to San Antonio.

    The stories these "books" tell range from fascinating to heartbreaking and everything in between. And that's the very point of the organization--to prove that no person can be summed up in just one word. It seeks to show people that you truly can't judge a book by its cover---or by its title or label.