题干

如图所示是小阳在沈阳科技宫看到的静电游戏“怒发冲冠”,这是因为人接触静电球时,人体是____(选填“导体”或“绝缘体”),电荷通过人体传到头发上,由于头发____而使头发竖起来.

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导体,带同种电荷互相排斥

同类题1

完形填空。

    It was the end of the week at the village school. The bell had rung, and the children had run out into the bright sunshine, wild with laughter and fun. All were happy but poor Davy. He came out last and very1. He was in trouble, and the bright, golden sunlight did not make him2. He walked across the yard, and sat down on a stone behind the old maple. A little bird on the highest branch sang just to make him3. But Davy did not notice it. He was thinking of the4words that had been said about his ragged clothes. The5stole out of his eyes, and ran down his cheeks. Poor little Davy had no6, and his mother had to work hard to keep him at school all by herself. He did not wish to trouble his mother; so he 7among the trees , and at last threw himself on the green moss under them. Just then his beloved teacher Mrs. Smith came8. She saw who it was, smith stopped to ask what was the9 . Davy did not speak, but the tears began to start. Mrs. Smith waited patiently10Davy told her all his  trouble. When he ended, she said11, “Davy. I have a plan which I think will help you.” “Oh , what is it ?” He said, sitting up with a look of 12while a tear fell upon a blue violet. “Well, how would you like to be a little flower13? And earn money?” “That would be jolly. But where shall I get my flowers?” he asked. “14, my boy, the answer to the question is just right in there15.” said Mrs. Smith. “Here are lively blue violets, down by the brook are white ones, and among the rocks are ferns and mosses. 16them all to my house, and I will help you17them.” Davy nodded and went home happily. Day after day. Davy hunted the woods for the18flowers, and the most beautiful ferns and mosses. After his teacher had helped him with new clothes. But for the19, and sold them. He soon carted enough money to buy new clothes. But for the20of his teacher, he couldn't have solved his problem. Now he could see the bright sunshine and hear the bird's singing.

同类题2

阅读下文,完成后面小题。

为爱挺直

郭华悦

    ①父亲早早去世,为了生计,母亲在家乡摆了个水果摊,每天天没亮就要起来张罗。到了七点左右,一切准备妥当了,于是用三轮的脚踏车,载着顺路的他和一车水果,在晨曦中一路奋进。

    ②母亲的背驼得很严重。到了冬天,在这个北方的小城里,北风裹着雪花,一路肆虐。每当这个时候,母亲总是用力地挺直了背。躲在母亲背后的他,恍然发现母亲的驼背直了不少。

    ③到了学校,他欢呼着跳下车,把这个惊喜发现告诉了母亲。他还沾沾自喜地叮嘱母亲,说不定蹬脚踏车有助于纠正驼背呢。母亲笑了笑,不以为意。可是懵懂的他却天真地认为,如果母亲能直起背来,自己就不会被同学叫做“小罗锅”了。

    ④母亲蹬脚踏车挺直的脊背,让他看到了希望。可是日复一日,他失望地发现,母亲蹬脚踏车时,脊背是直的,可一下车,却又成了驼背。于是,同学们的嘲笑始终伴随着他。

    ⑤后来,他考上了大学,毕业后,留在了城市里。没过了几年,他娶了个漂亮的妻子,也增添了一个可爱的小生命。母亲一直想过来看看孙女,可是他碍于面子,始终说自己忙,不断推脱。

    ⑥直到有一天,他骑着自行车,送四岁的女儿去幼儿园。那天的北风格外地大,刮在脸上竟有些生疼。女儿惊叫了几声,他于是下意识地挺直脊背,挡住迎风而来的寒风。风像刀子一样,在身上刮过,他却始终牵挂着后座上的女儿。

    ⑦那一刻,他突然想起了老家的母亲。他也终于明白,那些风雨交加的早上,母亲奋力地挺直了一直被他嫌弃的驼背,为后座的他挡住了刺骨的风雪。母亲的背,因为爱而挺直。可他不知道的是,每次把他送到学校,回到水果摊后,母亲的背总会疼上大半天。这样的戏,在他年少时光中,日复一日的上演。

    ⑧他的心里,突然涌进了阵阵酸楚。母亲的背是驼的,爱却很直。每个子女的身前,都有一堵挡风遮雨的挺直脊背,那是一堵爱的厚墙。