题干

如图1所示,为某卫生间的地漏结构示意图,它利用了____原理.如图2 所示,是一台手摇式发电机,它利用了____原理.

上一题 下一题 0.0难度 选择题 更新时间:2019-10-26 09:47:06

答案(点此获取答案解析)

连通器,电磁感应

同类题2

                                                                                                                父  亲
         1989年发生在美国洛杉矶一带的大地震,在不到4分钟的时间里,使30万人受到伤害。
         在混乱的废墟中,一个年轻的父亲安顿好受伤的妻子,便冲向他7岁的儿子上学的学校。他眼前,那个昔日充满孩子们欢笑的漂亮的三层教室楼已经变成了一片废墟。他顿时感到眼前一片漆黑,大喊:“阿曼达,我的儿子!”跪在地上大哭了一阵后,他猛地想起自己常对儿子说的一句话:“不论发生什么,我总会跟你在一起!”他坚定地站起身,向那片废墟走去。他知道儿子的教室在一层左后角处,他疾步走到那里,开始动手。
        在他清理挖掘时,不断有孩子的父母急匆匆地赶来,哭喊过后,他们绝望地离开了。有些人上来拉住这位父亲说:“太晚了,他们已经死了。”这位父亲双眼直直地看着这些好心人,问道:“谁愿意来帮助我?”没人给他肯定的回答,他便埋头挖着。救火队长挡住他:“太危险了,随时可能起火爆炸,请你离开。”这位父亲问:“你是不是来帮助我?”警察走过来:“你很难过,难以控制自己,可这样不但不利于你自己,对他人也有危险,马上回家去吧。”“你是不是来帮助我?”人们都摇头叹息着走开了,都认为这位父亲因失去孩子而精神失常了。
         这位父亲心中只有一个念头:“儿子在等着我。”他挖了8个小时、12个小时、24个小时、36个小时,没人再来阻挡他。他满脸灰尘,双眼布满血丝,浑身上下破烂不堪,到处是血迹。
         到第38个小时,他突然听到底下传出孩子的声音:“爸爸,是你吗?”是儿子的声音!父亲大喊:”阿曼达,我的儿子!”“爸爸,真的是你吗?”“是我,是爸爸,我的儿子。”“我告诉同学们不要害怕,说只要我爸爸活着就一定来救我,也就能救出大家。因为你说过不论发生什么,你总会和我在一起!”“你现在怎么样?有几个孩子活着?”“我们这里有14个同学,都活着,我们都在教室的墙角,房顶塌下来架了个大三角形,我们没被砸着。”父亲大声向四周呼喊:“这里有14个孩子,都活着!快来人!”过路的几个人赶紧上前帮忙。50分钟后,一个安全的小出口开辟了出来。父亲声音颤抖地说:“出来吧!阿曼达。”“不,爸爸。先让别的同学出去吧!我知道你会跟我在一起,我不怕。不论发生什么,我知道你总会跟我在一起。”这对了不起的父子在经历了巨大的磨难后,无比幸福地紧紧地拥抱在一起。

同类题3

      Jeans have become one piece of clothing worn by the most people in the world. Everybody wears them, from the farmer to the lawyer and from models to housewives. But why have jeans become so popular?You'll get many answers. For some people they look cool, for others jeans are just comfortable. 
      Jeans were first stronger trousers made for farm workers in the states of the American west. In the eastern part of the US jeans were hardly worn at all. They were connected with farm people and the workers. So the rich wouldn't like to wear them. 
    It was James Dean and Marlon Brando that made them popular in movies and everyone started to wear them. They were a symbol of the rebellion of young people during the 1950s and 1960s. So these new trousers were not allowed in American schools and sometimes in theatres and cinemas. As time went on,jeans became more acceptable. American people in Europe and Japan often wore them when they were not on duty to show that they were Americans. The trousers showed the world a happier way of life, something that people needed, especially after what they had gone through in World War II. 
     Jeans had other advantages as well. They didn't need to be washed as often as other trousers and women didn't need to iron them. This became more important as more and more women started working and had less time for housework. 
    Today jeans are an important part of our lives. They are always washed a few times before they are sold to give them a faded look.