题干

如图所示是某规格的小灯泡L和定值电阻R的U﹣I图象。

(1)图中表示小灯泡U﹣I图象的是      (填序号);

(2)若它们串联、并联时总电阻的值分别为R和R,请在对应的图上坐标区域内画出它们的U﹣I图象(R、R的U﹣I图象分别用③和④表示);

(3)当它们分别以串联和并联两种方式接在同一稳压电源(已知电源电压不高于10V)两端时,从电源流出的电流变化了0.45A,求该稳压电源的电压及并联电路消耗的总功率。

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答案(点此获取答案解析)

(1)②

(2)如下图

(3)该稳压电源的电压5V;并联电路消耗的总功率3W

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       ②某心理学专家小组以实际从事创造性工作的人与不从事此类工作的人为对象进行了调查研究,并得出如下结论:“富于创造力的人,认为自己具有创造力;缺乏创造力的人,不认为自己具有创造力。”
       ③认为“我不具备创造力”的人当中,有的觉得创造力仅仅是贝多芬、爱因斯坦以及莎士比亚他们的,从而进行自我压制。不言而喻,在创造的宇宙里,贝多芬、爱因斯坦、莎士比亚是光辉灿烂的明星。然而在大多数情况下,即便是他们,也并非轻而易举就能获得如此非凡的灵感。相反,这种非凡的灵感,往往产生于这样的过程:关注极其普通,甚至一闪念的想法,并对它反复推敲,逐渐充实。
       ④由此看来,区分一个人是否拥有创造力,主要根据之一是,拥有创造力的人留意自己细小的想法。即使他们不知道将来会产生怎样的结果,但他们很清楚,小的创意会打开大的突破口,并坚信自己一定能使之变为现实。
       ⑤任何人都拥有创造力,首先要坚信这一点。关键是要经常保持好奇心,不断积累知识;不满足于一个答案,而去探求新思路,去运用所获得的知识;一旦产生小的灵感,相信它的价值,并锲而不舍地把它发展下去。如果能做到这些,你一定会成为一个富有创造性的人。

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    Street art is a very popular form of art that is spreading quickly all over the world. You can find it on building, sidewalks, street sings and trash cans from Tokyo to Paris, and from Moscow to Cape Town. Street art has become a global culture and even art museums and galleries are collecting the works of street artists. Even advertising companies also use street art in their ads due to its popularity.

    Street art started out very secretly because it's illegal to paint on public and private property without permission. People often have different opinions about street art. Some people think it is a crime with others think it's a new form of culture.

    Art experts claim that the movement began in New York in the 1960s. Young adults sprayed words and images on walls and trains. This colorful and energetic style of writing became known as graffiti(涂鸦). Graffiti art showed that young people wanted to rebel against society. They didn't want to accept rules, and they travelled around cities to create paintings that everyone could see. In many cases, they had trouble with the police and the local government.

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    Street artists do their work for some reasons. Some of them do not like the artists who make so much money in galleries and museums. They choose street art because it is closer to common people. Some artists try to express their political opinion in their works. They often want to protest against big firms and corporations. Others like to do things that are forbidden and hope they don't get caught.

    In today's world, the Internet has a big influence on street art. Artists can show their pictures to people all over the world. Many city residents, however, say that seeing a picture on the Internet is never as good as seeing it alive. The street art movement lives with the energy and life of a big city. There it will continue to change and grow.