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如图甲所示,是小聪家的电热开水器,有加热档和保温档,铭牌部分参数如表所示,其简化电路图如图乙所示,其中R1和R2均为加热电阻,且阻值不随温度而变化。[c=4.2×103J/(kg•℃)]

额定电压

加热电阻

保温挡额定功率

  1. (1) 发热电阻R1的阻值是多少?
  2. (2) 电热开水器中质量为10kg、初温为15℃的水温度升高到95℃,水吸收的热量是多少?
  3. (3) 小聪关闭家里其他所有用电器,只让电热开水器以高温档工作,发现在30s内家中如图丙所示的电能表的转盘转了25转,此时电热开水器是正常工作吗?
生活处处是物理,留心观察皆学问。下列物态变化,说法正确的是

A . 水沸腾时如果继续加热,水因吸热温度会升高 B . 夏天,剥开冰棒纸,冰棒上冒的“白气”是水蒸气 C . 冬天,向手心“呵气”,口中呼出的水蒸气因液化放热而使手心变暖 D . 衣柜离的樟脑球变小是升华现象,需要放热
我能根据意思写词语。

①水势广大的样子,形容声势广阔壮大。

②颜色繁多,非常好看。

③高而险峻的山岭。

下列物态变化中,属于熔化现象的是(   )
A . 冬天,人嘴里呼出“白气” B . 夏天,人吃冰棒感觉凉爽 C . 用纸锅烧水,水沸腾但锅不会燃烧 D . 游泳的人刚从水中出来,感觉特别冷
不等式组 的解集是x<m+2,则m的取值范围应为
阅读下面短文,根据文章大意用所给单词的适当形式填空(未提供单词的,限填一词),使文章意思完整、正确。

Before paper was invented, people wrote or drew on materials such as bamboo, silk, animal skin and wooden blocks.Writing materials were really expensive and few people (learn) to read., few people wrote.This all changed, thanks to a man named Cai Lun.

We know paper had already existed(存在)in China, but the process for producing it was difficult and the paper was of low quality. Cai Lun began experimenting(试验)with many different materials and different methods  ( turn )those materials into paper. In the year 105, he made it from tree bark, bamboo, cloth rags and fishing nets.His paper was stronger and cheaper than any paper that had been made before.

With Cai Lun's papermaking method, Chinese culture grew more  (rapid) over the next several centuries. That's because ideas were much easier to share and more people learned to read. The use paper spread abroad, helping other cultures record and spread (they) ideas. Today, Cai Lun is considered national hero in  (Chinese). But the whole world should remember the (clever) Chinese papermaker in the world forever.

多媒体计算机能够采用以(    )方式与人交互信息。
A . 文字 B . 声音 C . 图像和动画 D . 以上选项都是
防止食品腐败可以采用不同的方法,下列适于较长时间保存食品的是(  )

①高温  ②低温  ③保持湿润  ④保持干燥  ⑤暴露在空气中  ⑥隔绝空气.

A . ①③⑤ B . ②④⑥ C . ①③⑥ D . ②④⑤
取两个相同的验电器甲和乙,使甲带正电,乙不带电。如图所示,可以看到甲的金属箔张开,乙的金属箔闭合,用带绝缘柄的金属棒把甲和乙连接起来会发现验电器金属箔的张角变化情况及电荷运动、电流方向说法正确的是(   )

A . 甲减小,乙增大,正电荷从甲到乙方向运动 B . 甲、乙都减小,负电荷从乙到甲方向运动 C . 甲、乙都不变,电流方向是从乙到甲 D . 甲减小,乙增大,电流方向是从甲到乙
现有镁条、铝粉、铜片、氧化铝、氧化铁、氯酸钾及其它常用的实验用品和仪器,根据现有药品,请你设计简单实验验证铝、铁金属单质的还原性强弱.依据你设计的实验方案,回答下列问题:

(1)实验原理:  ;(用化学方程式表示)

(2)实验中所需的化学仪器有 

(3)实验探究:取少量反应所得到的固体混合物,将其溶于足量稀H2SO4 , 滴加KSCN溶液无明显现象, (填“能”或“不能”)说明固体混合物中无Fe2O3 , 理由是:  (用离子方程式表示).

the door, please.

—OK.

I can swim and I can____ play football.
A . too B . to C . also D . and
看拼音,写词语。

gāo bǐng

zhà  yóu

fēn  fù

ài  mù

xián  qì

guì  huā

jīng  qiǎo

bái  hè

某同学欲配制质量分数为6.0%的食盐水80克,在用托盘天平称量食盐时,他将食盐和砝码的位置颠倒了(1克以下用游码),那么他实际所配制溶液的质量分数为(     )
A . 等于4.0% B . 大于4.0%,小于6.0% C . 等于6.0% D . 大于6.0%
Wait a minute. I ________ you an interesting story.
A . will tell B . tell C . told D . have told
在学习《坚持宪法至上》这一单元后,同学们对宪法产生了更为深刻的认识。为了更好地理解所学内容,同学们准备组织一次探讨活动,请你也参与其中。

(认知宪法)

1954年9月20日,中华人民共和国第一届全国人民代表大会第一次会议通过了《中华人民共和国宪法》。宪法进一步确认了我国的国体和政体,为人民当家作主提供了可靠的制度保障和宪法依据;宪法不仅组织国家机构,授予国家机构相应职权,而且严格规范职权的行使,切实维护人民的根本利益。

(宪法监督)

十九大报告明确提出要“加强宪法实施和监督,推进合宪性审查工作,维护宪法权威。”

  1. (1) 宪法规定的我国的国体和政体分别是什么?
  2. (2) 划线部分说明我国宪法的核心价值追求是什么?
  3. (3) 宪法规定,行使监督宪法实施职权的是哪一机关?
  4. (4) 除了推进合宪性审查工作外,我国宪法监督的内容还包括什么?
  5. (5) (生活践行)在日常生活中,我们践行宪法应当如何做?
名著阅读。
  1. (1) 下列有关《傅雷家书》内容的表述 ,不正确的一项是(   )  
    A . 在与傅聪讨论诗词艺术时,傅雷认为白居易对音乐与情绪的关系领悟得很深。 B . 傅雷希望傅聪能通过多写书信来训练文笔,尤其是训练其思想、理智、才智。 C . 傅雷认为一般艺术家偏于理智、冷静,就因为他们停留在感性认识的阶段上。 D . 傅雷在人格修养方面提醒傅聪要先批评自己,指点别人不要有“好为人师”之感。
  2. (2) 《傅雷家书》之所以‘著名’,不仅因为其文字,更因傅雷的拳拳爱子之心。请结合家书具体内容,谈谈作者的爱子之心。
阅读下面材料,在空白处填入适当的内容(1个单词)或括号内单词的正确形式。

    A recently survey showsthe students of our school like to do in their spare time. Much to my(surprising), more than half of the students like doing sports, only eight percent students prefer(read). It seems even worse that about 36 percent students would like(surf) the Internet. There are also a few studentsthink that playing musical instruments is wonderful according to the chart.

    In my opinion  teenagers should do more(exercise) and reading because it is our duty to study better for our future. We know that surfing the Internet can give us information that we need, but many students can't controland spend too much time surfing the Internet. So we can say it will do harmthem if the students are crazy about it. The best way to solve the problem is to make students form their own good hobbies.in this way can the students enjoy their study and life.

Mother (wash) clothes when I (get) home from school yesterday afternoon.
补写出下列名篇名句中的空缺部分。
  1. (1) 王安石的《游褒禅山记》中与“天生一个仙人洞,无限风光在险峰”意思相近的两句是“。”
  2. (2) 曹操在《短歌行》中,借写姑娘思念情人来表达渴慕贤才之意的句子是“。”
  3. (3) 早在千年之前,屈原就在《离骚》中以“”教导我们“道不同,不相为谋”。
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