题干

实验室里常用验电器来检验物体是否带电,其工作原理是____,用丝绸摩擦过的玻璃棒接触验电器上的金属球后,验电器的金属箔张开,说明验电器也带上了____(填“正”或“负”)电荷,这时验电器所带的电子总数与玻璃棒接触验电器前相比要____(填“增多”或“减少”或“不变”)。
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同种电荷相斥,正,减少

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    One fine afternoon I was walking along Fifth Avenue when I remembered that it was necessary to buy a pair of socks. I turned into the first sock shop that caught my eye, and a boy clerk who could not have been more than 17 years old came forward.

    “What can I do for you, sir?”

    “I wish to buy a pair of socks.”

    His eyes glowed. “Did you know that you had come into the best place in the world to buy socks?” I had not been aware of that.

    “Come with me,” said the boy happily. He began to haul (用力拖) down from the shelves box after box.

    “Hold on, boy, I am going to buy only one pair!”

    “I know that,” said he, “but I want you to see how beautiful these are. Aren't they wonderful?” There was on his face an expression of joy, as if he were showing to me the mysteries of his religion.

    “My friend,” said I, “if this is not just the enthusiasm (热情) that comes from novelty (新鲜), if you can keep up this day after day, in ten years you will own every sock in the United States.”

    In many shops the customer has to wait for someone to serve him. And when finally some clerk does notice you, you are made to feel as if you were disturbing him. He displays no interest either in you or in the goods he is paid to sell.

    Yet possibly that very clerk who is now so cold began his career with enthusiasm. As time goes by, the enthusiasm is gradually gone; his only pleasures were found outside of working hours. He became a mechanical (机械的), not inspired, salesman.

    I have observed such change in the lives of so many people in so many occupations that I have come to the conclusion that the fastest road to failure is to do things mechanically.