题海网,海量题库;找题库、找试卷、找答案就上题海网。

如图所示,平行板电容器与直流电源、理想二极管(正向电阻为零可以视为短路,反向电阻无穷大可以视为断路)连接,电源负极接地.初始电容器不带电,闭合开关S稳定后,一带电油滴位于电容器极板间的P点且处于静止状态。下列说法正确的是(    )

A . 减小极板间的正对面积,带电油滴会向下移动,且P点的电势会降低 B . 减小极板间的正对面积,带电油滴会向上移动,且P点的电势会降低 C . 将下极板上移,带电油滴向上运动 D . 断开开关S,带电油滴将向下运动
下列属于吸热反应是(   )
A . 金属钠与水的反应 B . 盐酸与氢氧化钠的反应 C . 铝与氧化铁的铝热反应 D . NH4Cl晶体与Ba(OH)2·8H2O晶体反应
The parrot can speak English. It _____ so interesting.
A . feels B . sounds C . smells D . looks
根据反应:2Ag++Cu═Cu2++2Ag,设计如图所示原电池,下列说法错误的是(   )

A . X可以是银或石墨 B . 电子从铜电极经外电路流向X电极 C . Y是硫酸铜溶液 D . X极上的电极反应式为Ag++e═Ag
卡德纳斯改革是墨西哥民族资产阶级领导的反帝反封建的改革。下列关于其改革的说法不正确的是(   )
A . 打击了寡头势力,在全国范围内分配土地 B . 鼓励私人兴办服务业和大型工业 C . 提出发展教育,提高人民文化水平 D . 巩固了墨西哥资产阶级革命的成果
阅读下面短文, 掌握其大意,然后从每题所给的 A、B、C、D 四个选项中选出最佳选项

A long time ago, there was a very big tree. A little boy loved to come and play around it 1 He loved the tree and the tree loved to play with him. Time went by. The little boy had grown up and he no longer (不在) played around the tree. One day, the boy came back and the tree was so2"Come and play with me!" the tree said." I don't have time  3. I have to work for my family. We need a house. Can you help me?" "Sorry, I don't have a house. 4you can cut off my branches (树枝) to build your house." So the boy cut all the branches of the tree and left 5

The tree was glad to see him happy, but the boy didn't come after that.

The tree was lonely and sad. One hot summer day, the boy came back and the tree was happy." Come and play6me!" the tree said." I am sad and getting old. I want to go sailing (航行) to  relax7. Can you give me a 8?"" Use my trunk (树干) to build the boat. You can sail and be happy." So the boy9the tree trunk to make a boat. He went sailing and did not show up for a long time.10, the boy came back after he left for so many years." Sorry, my boy, but I don't have anything for you. The only thing left is my dying roots." The tree said with tears." I don't need much now, just a 11to rest. I am tired after all these years."

The boy answered." Good! Old tree roots are the 12place to rest. Come here, please sit down with me and have a rest." The boy sat down and the tree was glad and smiled with tears.

This is a story of everyone. The tree is our 13

When we were young, we loved to play with Mom and Dad. When we 14, we leave them, and only come to them when we need something or when we are in trouble. No matter what, parents will always be there and give everything they have to make us happy. You may think that the boy isn't nice to the tree but that's 15all of us are doing to our parents.

(1)
A . any day B . some day C . one day D . every day
(2)
A . interested B . excited C . relaxed D . sad
(3)
A . to play B . to come C . to sleep D . to reply
(4)
A . So B . And C . But D . Or
(5)
A . happily B . quietly C . quickly D . finally
(6)
A . for B . on C . down D . with
(7)
A . myself B . yourself C . himself D . oneself
(8)
A . house B . steamboat C . boat D . ship
(9)
A . cut B . climbed C . killed D . picked
(10)
A . Luckily B . Finally C . Suddenly D . Happily
(11)
A . room B . place C . tree D . boat
(12)
A . worst B . first C . best D . last
(13)
A . friend B . child C . teacher D . parent
(14)
A . get up B . stand up C . give up D . grow up
(15)
A . how B . why C . what D . when
一本连环画的价钱是3.2元,一本故事书的价钱是2.7元.连环画比故事书贵元.
                 
  1. (1) 某同学连接了如图所示的电路,闭合开关后,两灯泡正常发光,把导线连接在L2两端,发现L1,L2

    图片_x0020_594588954

  2. (2) 如图,该同学将同一个小灯泡分别接在一节和两节干电池两端,发现接两节干电池的小灯泡发光(选填“较亮”、“较暗”),说明电路中电流的强弱与有关。
照样子写词语。
  1. (1) 眼巴巴(ABB):   
  2. (2) 兴致勃勃(ABCC):   
  3. (3) 东倒西歪(意思相反):   
  4. (4) 龙飞凤舞(动物名称):   
将点A(﹣2,3)通过以下哪种方式的平移,得到点A'(﹣5,7)(   )
A . 沿x轴向右平移3个单位长度,再沿y轴向上平移4个单位长度 B . 沿x轴向左平移3个单位长度,再沿y轴向下平移4个单位长度 C . 沿x轴向左平移4个单位长度,再沿y轴向上平移3个单位长度 D . 沿x轴向左平移3个单位长度,再沿y轴向上平移4个单位长度
How is it?              

A . It's sweet and nice. B . I don't like fish.
小丽站在舞蹈室内竖直放置的平面镜前2m处,则她在平面镜中的像距她m,当她向平面镜靠近的过程中,她在平面镜中像的大小(填“变大”、“变小”或“不变“)。
指出下列句子运用的修辞手法,并分析其作用
  1. (1) 我来了,雷电不喧嚷,风也不拥挤
  2. (2) 我的爱心像丝缕那样把天地织在一起
  3. (3) 君不见,柳条儿见了我笑弯了腰啊

        石狮子见了我笑出了泪啊

        小燕子见了我笑斜了翅膀啊

反应2KMnO4+16HCl=2MnCl2+2KCl+5Cl2↑+8H2O中,氧化剂是,还原剂是
下列人体必须的微量元素中,属于金属元素的是(  )

A . 碘  B . C . D .
计算x7÷x3的结果等于 

成语是中华民族智慧的结晶,以下成语所描述的变化中涉及化学变化的是 (    )
A . 百炼成钢    B . 聚沙成塔    C . 木已成舟    D . 滴水成冰
毕加索曾说:“我的没衣服画中都装有我的血,这就是我的画的含义”。下列属于他的代表作品是( )       
A . 《蒙娜丽莎》 B . 《最后的晚餐》 C . 《向日葵》 D . 《格尔尼卡》
1492年,他受西班牙王室的资助,率领由三艘不大的船组成的船队,从西班牙启程,开始向西航行横渡大西洋,经过两个月的航行,历经千辛万苦,他们到达了……

请回答:

  1. (1) 材料中的“他”是谁?

  2. (2) 他向西航行的目的是什么?为什么要选择向西航行?

  3. (3) 他始终认为自己到达了哪里?称当地居民为什么人?

  4. (4) 你认为我们应该学习航海家的什么精神?

已知椭圆C: )的离心率为 ,过右焦点且垂直于长轴的直线与椭圆C交于P,Q两点,且 .
  1. (1) 求椭圆C的方程;
  2. (2) A,B是椭圆C上的两个不同点,若直线 的斜率之积为 (以O为坐标原点),M是 的中点,连接 并延长交椭圆C于点N,求 的值.
教材章节知识点
年级分类
最近更新