题干

小芳同学在探究“决定导体电阻大小的因素”时,做出了如下猜想:

猜想①:在温度不变时,导体的电阻与导体的材料有关;

猜想②:在温度不变时,导体的电阻与导体的长度有关;

猜想③:在温度不变时,导体的电阻与导体的横被面积有关.

供她选择的导体如下表所示:

序号

材料

长度(m)

横截面积(mm2

A

镍铬合金

0.8

0.5

B

锰铜

0.8

1

C

锰铜

0.8

0.5

D

锰铜

1.2

0.5

她画出了实验电路图,并按要求正确地连接了电路.请完成下列填空(只填序号):

上一题 下一题 0.0难度 选择题 更新时间:2019-04-27 12:46:09

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同类题3

阅读短文,根据短文内容完成表格内容。

Steve Jobs was famous for starting Apple Computers. In a speech to graduating students at Stanford University, Jobs told students about some of life-changing experiences. Jobs believed these experiences helped him achieve success.

Job's biological mother was a college student. As a young mother, she felt unable to bring Jobs up so she put him up for adoption. Job's adopted parents were simple working-class people. When Jobs was 17, his parents used their saving to send him to college.

After six months of college, Jobs decided it was not for him. Around that time, he had read a quotation that went something like,“If you live each day as if it was your last, someday you’ll most certainly be right.”The quotation made him think about his life and his future. He started to question if he should stay in college. Was he doing what he really wanted to do? Eventually, he decided he had to change something; he decided to drop out of college.

Jobs was lucky because he knew what he loved to do. He started Apple Computers in his parents’ garage with a friend when he was 20.  In just ten years, Apple grew into a $2 billion company. However in 1985, Jobs was fired from the company.

Jobs was shocked. He lost everything at once. He quickly realized that he still loved what he did, and over the next five years, he started two highly successful companies. next and Pixar. Jobs also met his future wife, Laurence. Jobs was happily married with a family, working for Apple again and living every day as if it were his last.

             

Paragraph 1

Steve Jobs was famous for starting Apple Company. He believed that ____ helped him achieve success.

Paragraph 2

Jobs’adopted parents were simple working-class people. They ____  that they could only use their savings for Jobs’ college education.

Paragraph 3

A quotation made Jobs think about his life and his future. After six months of college, Jobs didn't think ____  and he decided to leave college.

Paragraph 4-5

After ____  of firing from Apple, quickly Jobs realized he still loved what he did and started two highly successful companies.

Conclusion    

According to Jobs’ story, if we want to achieve success, we should make a right decision, do what we love, never give up and ____ 

同类题4

阅读下面的文章,完成小题。

时光不旧,只是落满尘灰

朱成玉

       ①那时我20岁,却在经历人生的秋天,满目落红,遍地枯草,大有“晚景凄凉”的味道。在我自己看来,当时的窘境甚至不如隔壁的那个孤寡老人。

       ②他没有退休金,每日里靠捡拾垃圾艰难度日。喝酒算是他一天中唯一的一点乐趣吧。只有在喝点小酒的时候,那院子里才有了点儿活人的气息。那样的时候,我甚至能听到他哼着一些古老而神秘的曲调。

       ③他的院子里堆着的都是捡来的没来得及去卖的破烂,就是这廉价的破烂,竟然也遭遇了盗贼。那盗贼就是我。

       ④高考落榜后,父母让我去工厂做学徒工,我不去,关起门来坚持写作,梦想有一天可以写出名堂来。苍白无力的青春,空洞的辞藻,自然无法让我写出多么出彩的文章来。消极的我开始变得颓废,抽烟、酗酒、打架,“无恶不作”。邻家隔几天就上门来和父母讨说法,父母气急败坏,不再给我零花钱,任凭我“自生自灭”。我要写稿投稿,没钱买稿纸和邮票,只好打了他的主意,因为我注意到,他那些垃圾里,有一些本子,是可以拿来用的。

       ⑤他并没有太严厉地呵斥,只是对我说:“你不好好读书,来这破烂堆里翻个啥?破烂就是破烂,还能翻出什么稀罕玩意来?”说完他就往那对破烂里一躺,和那堆破烂融为一体,好像要告诉我,那破烂是他的,也就他把那破烂当有用的东西吧。“嘿嘿,我也是个破烂。你来翻翻,看我口袋里有没有点儿值钱的东西。”

       ⑥我的脸羞臊得通红,只好和他坦白,说自己看中了他捡来的那些本子。

       ⑦“不过话说回来,破烂也分两种,一种是完全没有用的,一种是还有一点利用价值的,比如我捡的这种,还是可以换回一点钱的。”那天他喝了酒,心情不错,没有和我发火。借着酒劲儿,还对我进行了一番教诲,“人啊,不管多糟糕,哪怕你狼狈得像个垃圾一样,只要用心,你也会是那可以回收利用的垃圾。相反,你若自暴自弃,沉沦堕落,那么你就是把自己扔进了不可回收的垃圾箱。”

       ⑧听着这话,一点不像一个捡破烂的老人说的,反倒像我的语文老师在课堂上给我讲的。

       ⑨为了“惩罚”我,他说,“去给我把窗玻璃给擦了吧,很久没擦了,都看不到外面的东西了。”

       ⑩我只好乖乖地就去擦玻璃。玻璃擦干净了,晦暗的屋子一下子亮堂了起来。他心情很好,招呼我喝一口。我捏着鼻子喝了一口,辣得不行,直吐舌头,他倒是乐得前仰后合。

       ⑪最后,他在自己的垃圾里仔细挑拣,把那些我能用到的本子都给了我。

       ⑫“该惩罚也惩罚了,不过你既然帮我把玻璃擦得那么干净,也得奖励奖励,这些就奖励给你吧。”

       ⑬我流着泪接过那一摞本子,脏兮兮、皱巴巴已近迟暮的本子,我却坚信自己,可以在那上面写出干干净净,青春靓丽的文字来。

       ⑭一度以为,自己荒废了光阴,不可救药。但这个可敬的老人让我知道,时光还没有被我用旧,只是蒙上了一层灰垢而已。只要用心去擦一擦,那隐匿起来的时光随时都可以亮洁如新。

(选自《当代青年》)