㈠ (2004东城区二模)如图所示,水平放置的两个平行金属板MN、PQ间存在匀强电场和匀强磁场.MN板带正电,P
电荷所受的洛伦兹力Ff=qvB,当电荷的速度为零时,洛伦兹力为零,故电荷在I点和K点只专受到电场力的作用,属故在这两点的加速度大小相等.方向相同,①是正确的,②是错误的.
由于J点是曲线上离MN板最远的点,说明电荷在J点具有与MN平行的速度,带电粒子在J点受到两个力的作用,即电场力和洛伦兹力;轨迹能够向上偏折,则说明洛伦兹力大于电场力,故③正确.④是错误的,综上所述,选项A正确的.
故选A
㈡ (2011东城区二模)如图所示电路图,把端点A、B接在电压U不变的电源两端,只闭合开关S1,电压表的示数为
把端点A、B接在电压U不变的电源两端,只闭合开关S1,等效电路图如图所示;
把端点A、D接同一电源两端,只闭合开关S1,等效电路图如图2所示;
把端点B、C接同一电源两端,只闭合开关S2,等效电路图如图3所示;
由图1可得:U1=I1R2=6V-------①
∵U1=6V,U1:U3=4:3,
∴U3=4.5V,
由图2可得,I3R2=4.5V-------②
由①②两式可得:
I1 |
I3 |
4 |
3 |
U2 |
R2 |
(30V)2 |
3Ω |
R2R3 |
R2+R3 |
3Ω×12Ω |
3Ω+12Ω |
㈢ (2014东城区二模)如图,四棱锥E-ABCD中,平面EAD⊥平面ABCD,DC∥AB,BC⊥CD,EA⊥ED,且AB=4,BC=CD=
㈣ 翻译中考英语阅读文章:北京市东城区2012中考英语二模C 篇阅读
Different colours can affect us in many different ways; that’s according to Verity Allen.
不同的颜色能以不同的方式影响我们,这话是维里蒂.艾伦说的。
In a new programme “Colour me Healthy”, Verity looks at the ways that colours can influence how hard we work and the choices we make. They can even change our emotions and even influence how healthy we are.
在新节目“为我健康增色”中,维里蒂观察色彩影响我们的方式方法,颜色影响我们工作的努力程度和我们做出的决定。它们甚至能改变我们的情绪,甚至能影响我们的健康程度。
“Have you ever noticed how people always use the same colours for the same things?” says Verity. “Our toothpaste is always white or blue or maybe red. It’s never green. Why not? For some reason we think that blue and white is clean, while we think of green procts(产品)as being a bit unpleasant.
“你是否曾注意过,人们总是同一种东西用同一款颜色,人们是怎样做的呢?”维里蒂说,“我们的牙刷总是白色或蓝色,又或许是红色。但绝不是绿色。为何不是?因为某些原因,我们觉得蓝色和白色是干净的,而我们认为绿颜色的产品有些不让人愉快。
It’s the same for businesses. We respect a company which writes its name in blue or black, but we don’t respect one that uses pink or orange. People who design设计new procts can use these ideas to influence what we buy.”
对企业来说,也是如此。我们尊敬以蓝色或黑色书写其名的公司,却不尊敬将名字写成粉色或橘色的公司。新产品的设计者可根据这些理念来影响我们所购买的东西。
During the programme, Verity studies eight different colours, two colours in each part.
在节目中,维里蒂研究八种不同的颜色,每两种分为一组。
She meets people who work in the colour instry, from people who design food packages, to people who name the colours of lipsticks.
她拜访那些在色彩领域工作的人,从食品包装设计师,到唇膏色彩命名者。
Some of the people she meets clearly have very little scientific knowledge to prove their ideas, such as the American “Colour Doctor” who believes that serious diseases can be treated successfully by the use of coloured lights.
她见过的人中,有些明显不具备科学的知识来证明他们的观点,比如说一位美国色彩医生,这位医生相信严重的疾病能用彩色灯成功治愈。
However, she also interviews real scientists who are studying the effects of green and red lights on mice, with some surprising results.
但是,她也采访那些真正的科学家,他们正在研究红绿灯对老鼠的影响,并取得了一些出人意料的成果。
Overall, it’s an interesting show, and anyone who watches it will probably find out something new.
总之,这是一个有意思的节目,任何一位看节目的人或许都能在其中发现新的东西。
But because Verity goes out of her way to be polite to everyone she meets on the programme, it’s up to you to make your own decisions about how much you should believe.
然而出于维里蒂对每一位节目受访者的礼貌,(受访者的话)其可信度有多少,就取决于你自己了。
(最后一句话的言外之意:维里蒂只作采访不作评论,观众自己看自己判断真假。)
㈤ (2014东城区二模)如图所示,放在水平地面上的杠杆AC能以B点为支点在竖直平面内转动,AC=0.8m,BC=0.6m
(1)当垫块D对物体H的支持力为时,物体E的质量最大.以杠杆为研究对象,受力分析如图1甲所示;以动滑轮和物体E为研究对象,受力分析如答图1乙所示;以物体H为研究对象,受力分析如答图1丙所示.
㈥ 东城二模2010英语答案
第一部分:听力理解(共三节,30分)
第一节(共5小题;每小题1.5分,满分7.5分)
1—5 BAC AA
第二节(10小题,每小题1.5分,满分15分)
6—10 CBBAC 11—15 CCABA
第三节(共5小题,每小题1.5分,满分7.5分)
第小题1.5分。如出现拼写错误不计分;出现大小写、单复数错误扣0.5分。
16.12 17.choice 18.shoes 19.12:15 20.food/snacks
第二部分:知识运用(共两节,45分)
第一节:单项填空(共15小题;每小题1分,满分15分)
21—25 CBDAA 26—30 BDCCB 31—35 BCABB
第二节:完形填空(共20小题;每小题1.5分,满分30分)
36—40 BDCDB 41—45 ABCAC 46—50 ABADC 51—55 ADBBA
第三部分:阅读理解(共两节,40分)
第一节(共15小题;每小题2分,满分30分)
56—60 DABAC 61—65 ACADD 66—70 CDABC
第二节(共5小题;每小题2分,满分10分)
71—75 GFEAB
第四部分:书面表达(共两节,35分)
第一节 情景作文(20分)
一、评分原则:
1.本题总分为20分,按5个档次给分。
2.评分时,先根据文章的内容和语言质量初步确定其档次,然后以该档冽的要求衡量,确
定或调整档次,最后给分。
3.评分时应考虑:内容要点、上下文的连贯、词汇和句式的多样性及语言的准确性。
4.拼写、标点或书写影响内容表达时,应视其影响程度予以考虑。英、美拼写及词汇用法
均可接受。
5.词数少于60,从总分中减去1分。
二、各档次的给分范围和要求:
第一档 完全完成了试题规定的任务。
●覆盖了所有内容要点;
●运用了多样的句式和丰富的词汇;
● 语言或用词方面有个别错误,但为尽可能表达丰富的内容所致;体现了较强的语言运用能力;
●有效地使用了语句间的连接成分,所写内容连贯、结构紧凑。
完全达到了预期的写作目的。
18分一20分
第二档 完全完成了试题规定的任务。
●覆盖了所有内容要点;
●运用的词汇和句式能满足任务要求;
●语言和用词方面基本准确,少许错误主要为尽可能表达丰富的内容所致;
●使用了简单的语句间连接成分,所写内容连贯。
达到了预期的写作目的。
15分一17分
第三档 基本完成了试题规定的任务。
●覆盖了内容要点;
●运用的词汇和句式基本满足任务要求;
●语言和用词方面有一些错误,但不影响理解。
基本达到了预期的写作目的。
12分一14分
第四档 未恰当完成试题规定的任务。
●漏掉或未描述清楚主要内容;
●所用句式和词汇有限;
●语法或用词方面的错误影响了对所写内容的理解。
未能清楚地传达信息。
6分一11分
第五档 未恰当完成试题规定的任务。
●明显遗漏主要内容;
●句式单调、词汇贫乏;
●语法和用词方面错误较多,严重影响了对所写内容的理解。
未能传达任何信息;所写内容与要求无关。
1分一5分
0分 未能传达任何信息;所写内容与要求无关。
三、One possible version:
Dear Tim,
I’ve received your email, asking me about my plan for the summer vacation. Now let me tell you something exciting.
I’ve applied to be a volunteer for the World Expo 2010 Shanghai and I’ll start working as soon as I have finished the entrance examination.
The exposition is a grand intermational gathering, which is expected to attract 70 million visitors from both home and abroad. And what makes it unique is that it is being held in a developing country for the first time. Can you imagine how proud I feed to be able to do my bit for this special occasion?
Speaking of the volunteer work, I’ll mainly help out in Beijing Pavilion, where I will show the visitors around and introce the magnificent buildings to them, such as the Forbidden City, the Bird’s Nest and so on. It’ll be a good chance to help the visitors to get to know about the culture of Beijing. Apart form my work as a volunteer, I will certainly pay a visit to different pavilions., I won’t miss seeing the great inventions and achievements on display and I can experience different cultures as well as exchange ideas with people around the world. Sounds fantastic, doesn’t it?
I hope you can come and see it for yourself.
㈦ 2011年东城区二模英语答案出来了吗
-20ABCBA BABAB ABCBC BCBCA
21-35BABDA ACBCB CACAC
36-55BDCAC BCADD BBCAD AADAB
56-75DBCAD BABAA CBCAC BBDDC
情景作文
One possible version:
The following is a survey about how young children go to school in the cities of Beijing,Tokyo and Seoul.From the survey we can see that about 75% of the Beijing children reach their schools within 20 minutes while in Tokoy and Seoul about 90% can manage this .As far as transpont is concerned ,all the children in Tokoy and Seoul go to school on foot while Beijing children take private cars,taixs and buses as well as walk.58.1% of the Beijing children are taken to and met at school by their parents while only about 3% of the Tokoy and Seoul children need help of this kind.They prefer to walk with friends.It seems children in Beijing are more dependent on their parents.
开放作文
One possible version:
@ means”at”,which is a sign used right in front of a certain address.This sign is used for e-mail.So I think it stands for the ”virtual world”in this picture,which is like a supermarket,huge and rich,where people are supposed to ask for and get anying they need.So logically,the fish stand for customers or people.On the one hand ,the ”fish” need the t for food, on the other hand,they are cheated by the”fishermen”behind the t.That's how I understand it.Does it make sense?
㈧ (2014东城区二模)如图,在△ABC中,AB=AC,AE是角平分线,BM平分∠ABC交AE于点M,经过B、M两点的⊙O交
(1)AE与⊙抄O相切.
理由如下:
连接OM,则OM=OB,
∴∠OMB=∠OBM.
∵BM平分∠ABC,
∴∠OBM=∠EBM.
∴∠OMB=∠EBM.
∴OM∥BC.
∴∠AMO=∠AEB.
在△ABC中,AB=AC,AE是角平分线,
∴AE⊥BC.
∴∠AEB=90°.
∴∠AMO=90°.
∴OM⊥AE.
∴AE与⊙O相切;
(2)在△ABC中,AB=AC,AE是角平分线,
∴BE=
1 |
2 |
1 |
3 |
1 |
3 |
BE |
cos∠ABC |
OM |
BE |
AO |
AB |
r |
2 |
6?r |
6 |
3 |
2 |
3 |
2 |