上海市闸北区2015学年度第二学期高三物理学期中练习卷
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2014-2015学年度第二学期模块测试高二物理第I卷共48分一.选择题:(本题共12小题,每小题4分,在每小题给出的四个选项中,第 1 ~ 8题只有一项符合题目要求,第9 ~ 12题有多项符合题目要求,全部选对的得4 分,选对但不全的得2分,有选错的得0 分。
答案涂在答题纸上相应的位置。
)1.如图所示,闭合圆导线线圈放置在匀强磁场中,线圈平面与磁场平行,其中ac、bd分别是平行、垂直于磁场方向的两条直径.试分析线圈做如下运动时,能产生感应电流的是()A.使线圈在纸面内平动B.使线圈平面沿垂直纸面方向向纸外平动C.使线圈以ac为轴转动D.使线圈以bd为轴转动2.如图所示,A、B是相同的白炽灯,L是自感系数很大、电阻可忽略的自感线圈。
下面说法正确的是A.闭合开关S时,B灯比A灯先亮,最后一样亮B.闭合开关S时,A灯比B灯先亮,最后一样亮C.闭合开关S稳定后断开开关S时,流过A灯中的电流方向与原来相同D.闭合开关S稳定后断开开关S时,A灯与B灯更亮一下后慢慢熄灭3.矩形线圈abcd在匀强磁场中绕垂直于磁场的轴匀速转动,线圈所围面积的磁通量Φ随时间t变化的规律如图所示,下面的说法正确的是A.t1时刻线圈中感应电动势最大B.t2时刻导线ad的速度方向跟磁感线垂直C.t2时刻线圈平面与中性面重合D.t4时刻线圈中感应电流方向改变4.如图所示的理想变压器,各表均为理想交流电表,R 1,R 2,R 3均为定值电阻,初级线圈加上电压有效值恒定的交变电流,当开关K 闭合时,下列说法正确的是( )A .A 1示数不变,A 2示数变大B .V 1示数变小,V 2示数变小C .V 1示数不变,V 2示数不变D .R 2消耗功率变小5. 一矩形线圈abcd 位于一随时间变化的匀强磁场内,磁场方向垂直线圈所在的平面向里(如图甲所示),磁感应强度B 随时间t变化的规律如图乙所示.以I 表示线圈中的感应电流(图甲中线圈上箭头方向为电流的正方向),则下列选项中能正确表示线圈中电流I 随时间t 变化规律的是6.如图所示,直角三角形导线框abc 以大小为v 的速度匀速通过有清晰边界的匀强磁场区域(匀强磁场区域的宽度大于导线框bc 边的长度),则此过程中导线框中感应电流随时间变化的规律为(规定逆时针方向的电流为正)7.如图所示,图甲和图乙分别表示正弦脉冲波和方波的交变电流与时间的变化关系.若使这两种电流分别通过两个完全相同的电阻,则经过1 min 后,两电阻消耗的电功之比W 甲∶W 乙为( )A .1∶2B .1∶2C .1∶3D .1∶68.现将电池组、滑动变阻器、带铁芯的线圈A、线圈B、电流计及电键按如图1所示连接.下列说法中正确的是A.电键闭合后,线圈A插入或拔出线圈B时都会引起电流计指针偏转B.线圈A插入线圈B中后,电键闭合后电流计指针偏转一角度后静止不动C.电键闭合后,使滑动变阻器的滑片P匀速滑动的过程,电流计指针无偏转D.电键闭合后,只有滑动变阻器的滑片P加速滑动,电流计指针才能偏转9.如图所示,金属铜球从距底端高h的绝缘光滑曲面无初速滚下,又沿曲面的另一侧上升,整个装置处在磁场中,则A.若磁场是匀强磁场,铜球滚上的最大高度小于hB.若磁场是匀强磁场,铜球滚上的最大高度等于hC.若是从左到右逐渐增强的非匀强磁场,铜球滚上的最大高度小于h。
2015年上海市高中毕业统一学业考试物理试卷本试卷共7页,满分150分,考试时间120分钟,全卷包括六大题,第一、第二大题为单项选择题目,第三大题为多项选择题目,第四大题为填空题目,第五大题为实验题,第六大题为计算题。
一、单项选择题目(共16分,每小题2分,每小题只有一个正确选项)1.X射线A.不是电磁波 B.具有反射和折射的特性C.只能在介质中传播 D.不能发生干涉和衍射2.如图,P为桥墩,A为靠近桥墩浮出水面的叶片,波源S连续振动,形成水波,此时叶片A静止不动。
为使水波能带动叶片振动,可用的方法是A.提高波源频率 B.降低波源频率C.增加波源距桥墩的距离 D.减小波源距桥墩的距离3.如图,鸟沿虚线斜向上加速飞行,空气对其作用力可能是A.1F B.2F C.3F D.4F4.一定质量的理想气体在升温过程中A.分子平均势能减小 B.每个分子速率都增大C.分子平均动能增大 C.分子间作用力先增大后减小5.铀核可以发生衰变和裂变,铀核的A.衰变和裂变都能自发发生 B.衰变和裂变都不能自发发生C.衰变能自发发生而裂变不能自发发生 D.衰变不能自发发生而裂变能自发发生6.23290Th经过一系列α衰变和β衰变后变成20882Pb,则20882Pb比23290Th少A.16个中子,8个质子 B.8个中子,16个质子C.24个中子,8个质子 D.8个中子,24个质子7.在α粒子散射实验中,电子对α粒子运动的影响可以忽略,这是因为与α粒子相比,电子A.电量太小 B.速度太小 C.体积太小 D.质量太小8.两个正、负点电荷周围电场线分布如图所示,P、Q为电场中两点,则A.正电荷由P静止释放能运动到QB.正电荷在P的加速度小于在Q的加速度C.负电荷在P的电势能高于在Q的电势能D.负电荷从P移动到Q,其间必有一点电势能为零二、单项选择题目(共24分,每小题3分,每小题只有一个正确选项)9.如图,长为h的水银柱将上端封闭的玻璃管内气体分割成两部分,A处管内外水银面相平。
专题十一、光的本性与原子核一、单项选择题(每小题2分)。
6.用如图所示装置做光电效应实验,下述正确的是C (A)光电效应现象是由爱因斯坦首先发现的 (B)实验现象揭示了光具有波动性(C)实验中,光电子从锌板逸出,验电器带正电 (D)实验中,若用可见光照射锌板,也能发生光电效应 8.某放射性元素经过11.4天有78的原子核发生了衰变,该元素的半衰期是A (A) 3.8天 (B) 5.7天 (C) 7.6天 (D) 11.4天1、下列说法符合历史事实的是 ( B ) A .贝可勒尔通过对天然放射现象的研究,发现了原子中存在原子核B .汤姆孙通过阴极射线在电场中偏转的实验,发现了阴极射线是由带负电的粒子组成的C .查德威克发现中子促使原子的核式结构模型的建立D .相对论的创立表明经典力学已不再适用2、关于中子,下列说法正确的是 ( B ) A .科学家用α粒子轰击氮核,通过人工转变发现了中子 B .中子能从石蜡中打出质子,γ光子不能从石蜡中打出质子 C .中子电离作用最大,贯穿本领也最大D .中子的衰变方程:2351951381920385403U n Sr Xe n +→++3.如图,用一定频率的单色光照射光电管时,电流表指针会发生偏转,则 (C ) A .电源右端应为正极B .流过电流表G 的电流大小取决于照射光的频率C .流过电流表G 的电流方向是a 流向bD .普朗克解释了光电效应并提出光子能量E =h ν1.天然放射性元素衰变时放出的β射线是( )A(A )电子流(B )光子流(C )中子流(D )质子流2.关于物理学史,下列说法中符合史实的是( )B(A )爱因斯坦为解释光的干涉现象提出了光子说 (B )麦克斯韦提出了光的电磁说(C )汤姆生发现了电子,并首先提出原子的核式结构模型(D )贝克勒尔在研究天然放射性的过程中发现了放射性元素钋(Po )和镭(Ra ) 4.关于超声波、微波和光波,下列说法中正确的是( )B(A )它们都是电磁波(B )超声波最容易产生衍射现象(C)微波的波长最短(D)只有光波可以发生干涉现象5.关于光电效应,下列说法中正确的是()D(A)发生光电效应时,入射光越强,光子的能量就越大(B)不同金属产生光电效应的入射光的最低频率是相同的(C)金属内的每个电子可以吸收一个或一个以上的光子,当它积累的动能足够大时,就能发生光电效应(D)如果入射光子的能量小于金属表面的电子克服原子核的引力而逸出时所需做的最小功,便不能发生光电效应1、关于α、β、γ三种射线,下列说法正确的是D(A)α射线是原子核自发放射出的氦核,它的穿透能力最强.(B)β射线是原子核外电子电离形成的电子流,它具有中等的穿透能力.(C)γ射线一般伴随着α或β射线产生,它的穿透能力最弱.(D)γ射线是电磁波,它的电离能力最弱.2、下列说法中正确的是 C(A)玛丽·居里首先提出原子的核式结构学说.(B)卢瑟福在 粒子散射实验中发现了电子.(C)查德威克在原子核人工转变的实验中发现了中子.(D)麦克斯韦为解释光电效应的实验规律提出了光子说.3、随着时代的发展,能源危机逐渐形成,现在科学家正在努力寻找新能源,而核能是现今比较普遍利用的新能源之一,核电站利用核能发电是人类利用核能的重要手段.据你判断,现已建成的核电站的能量来自于 C(A)天然放射性元素衰变放出的能量.(B)人工放射性同位素放出的的能量.(C)重核裂变放出的能量.(D)化学反应放出的能量.4、用一束紫外线照射某金属时能产生光电效应,能使该金属发射出的光电子的最大初动能增大的措施是B(A)改用红外线照射.(B)改用X射线照射.(C)改用强度更大的原紫外线照射.(D)延长原紫外线的照射时间.1、1. 如图,是一种小型验钞器,能显示纸币上的防伪标志。
上海市闸北区2007—2008学年度第二学期高三年级教学质量检测物理试卷(2008.4)(满分150分,考试时间120分钟)1.答卷前,考生务必将姓名、准考证号、校验码等填写清楚。
2.本试卷共8页,满分150分。
考试时间120分钟。
考生应用钢笔或圆珠笔将答案直接写在试卷上。
3.第20、21、22、23、24题要求写出必要的文字说明、方程式和重要的演算步骤。
只写出最后答案,而未写出主要演算过程的,不能得分。
有关物理量的数值计算问题,答案中必须明确写出数值和单位。
一、(20分)填空题。
本大题共5小题,每小题4分。
答案写在题中横线上的空白处或指定位置,不要求写出演算过程。
1.如图所示,质量为M 的气缸用质量为m 的活塞在缸内密封一定质量的理想气体,活塞跟缸壁间的摩擦不计,大气压为p 0,活塞的横截面积为S ,整个装置倒立在水平地面上。
当封闭气体温度为T 开时,活塞恰好跟地面接触,但没有受到地面对它的支持力.这时封闭气体的压强为__________。
当温度升高到某一值时,发现气缸恰好跟地面接触,但没有受到地面对它的支持力,这时封闭气体的温度为______________。
2.据报道,前不久科研人员使用输出功率为108W 的超高强度激光,在10-6s 的极短时间里,照射由重氢和碳制成的中空燃料球,把它加热到数百万摄氏度,进而引发了核聚变。
若所用激光的每个光子的能量为5eV ,那么该激光的频率是_________Hz ,在这10-6s 内发出的激光光子数为__________个。
(取h=6.6×10-34J s ,答案保留两位有效数字)3.如图所示,AB 是一根粗细均匀的均质杆,用轻绳AO 、BO挂于O 点,OAB能绕O 点在竖直平面转动。
AO <BO ,在A 点挂一重物P ,使AB 保持水平,C 为O 点正下方的杆上一点,已知AC 、BC 部分的质量分别为m1、m 2,重物P 的质量为m 3,则:m 1+m 3 m 2,轻绳AO 、BO 的拉力T AO T BO (填>、=或<)4. 如图所示,a 、b 、c 为匀强电场中的等势面,ab 的距离是bc 的一半,U b =0V,一负电荷以18焦的动能进入电场,到c 时,速度为零。
上海市2014-2015学年高三第二次六校联考物理试卷2015.3本试卷共10页,满分l50分,考试时间l20分钟。
全卷包括六大题,第一、二大题为单项选择题,第三大题为多项选择题,第四大题为填空题,第五大题为实验题,第六大题为计算题。
考生注意:1、答卷前,务必用钢笔或圆珠笔在答题纸正面清楚地填写姓名、准考证号,并将核对后的条形码贴在指定位置上,在答题纸反面清楚地填写姓名。
2、第一、第二大题的作答必须用2B铅笔涂在答题卡上相应区域内与试卷题号对应的位置,需要更改时,必须将原选项用橡皮擦去,重新选择。
第三、第四、第五和第六大题的作答必须用黑色的钢笔或圆珠笔写在答题纸上与试卷题号对应的位置(作图可用铅笔)。
3、第30、31、32、33题要求写出必要的文字说明、方程式和重要的演算步骤。
只写出最后答案,而未写出主要演算过程的,不能得分。
有关物理量的数值计算问题,答案中必须明确写出数值和单位。
一.单项选择题(每小题2分,共16分。
)1.人类对光的本性的认识经历了曲折的过程。
下列关于光的本性的陈述不符合...科学规律或历史事实的是()A.牛顿的“微粒说”与爱因斯坦的“光子说”本质上是一样的B.光的双缝干涉实验显示了光具有波动性C.麦克斯韦预言了光是一种电磁波D.光具有波粒二象性2.关于原子和原子核,下列说法中正确的是()A.汤姆孙发现了电子使人们认识到电子是组成物质的最小微粒B.原子核集中了原子的几乎全部正电荷和全部质量C.卢瑟福通过原子核的人工转变发现了质子D.β粒子是从原子核内发出的,说明原子核内有电子存在3. 在力学理论建立的过程中,有许多伟大的科学家做出了贡献。
关于科学家和他们的贡献,下列说法正确的是()A.第谷通过对天体运动的长期观察,发现了行星运动三定律B.亚里士多德认为力的真正效应总是改变物体的速度,而不仅仅是使之运动C.牛顿最早指出力不是维持物体运动的原因D.卡文迪什第一次在实验室里测出了引力常量4.如图所示,水平地面上堆放着原木,关于原木P在支撑点M、N处受力的方向,下列说法正确的是()A.M处受到的支持力竖直向上B. N处受到的支持力竖直向上C. M处受到的摩擦力沿MN方向D.N处受到的摩擦力沿水平方向5.已知声波在钢轨中传播的速度远大于在空气中传播的速度,则当声音由钢轨传到空气中时()A.频率变小,波长变长B.频率变大,波长变短C.频率不变,波长变长D.频率不变,波长变短6.对于曲线运动,下列说法中正确的是()A.速度方向和加速度方向不可能一致B.合外力一定与速度方向垂直C.合外力一定发生变化D.物体受到的摩擦力方向一定和速度方向平行7.游泳运动员以相对于水流恒定的速率垂直河岸过河,当水速突然增大时,则过河()A.路程增加、时间增加B.路程增加、时间不变C.路程增加、时间缩短D.路程、时间都不变8.下列选项中的各圆环大小相同,所带电荷量已在图中标出,且电荷均匀分布,各圆环间彼此绝缘。
2014、11市二中学2014学年第一学期高三物理期中考试试卷(时间120分钟,满分150分)一.单项选择题(共16分,每小题2分,每小题只有一个正确选项。
) 1、物体在做以下各种运动的过程中,运动状态保持不变的是(A).匀速直线运动 ( B).自由落体运动 ( C.)平抛运动 ( D).匀速圆周运动 2、在下述各力中,属于根据力的性质命名的是( )(A )回复力 (B )摩擦力 (C )向心力 (D )支持力 3表征物体作简谐运动快慢程度的物理量是[ ](A)回复力 (B)振幅 ( C)频率 ( D)位移4、从同一水平直线上的两位置分别沿同方向抛出两小球A 和B ,其运动轨迹如图,不计空气阻力。
要使两球在空中相遇,则必须( ) (A )先抛出A 球 (B )先抛出B 球 (C )同时抛出两球 (D )使两球质量相等5、如图力F 垂直作用在倾角为α的斜面体上,斜面体没被推动,则斜面体受到地面的静摩擦力大小为( )(A )0 (B )F cos α (C )F sin α (D )F tan α6、设地球半径为R ,一卫星在地面受到地球的万有引力为F ,则该卫星在离地面高度为2R 的圆形轨道上绕地球运行时受到地球的万有引力大小为((A )F /9 (B )F /4 (C )F /3 (D )F /27、如图一根均匀直杆OA 可绕O 轴在纸面内转动,开始A 端有竖直向上的力F 使OA 杆与竖直方向成α角(α<90°),现将力F 的方向沿逆时针方向缓慢转过90°,转动过程中,杆保持静止,则力F 和F 的力矩M 的变化情况是( )(A )都减小 (B )F 先减小后增大,M 不变(C )F 不变,M 先减小后增大 (D )F 和M 都先减小后增大8、如图所示,水平地面上有一个坑,其竖直截面为半圆,O 为圆心,AB 为沿水平方向的直径。
若在A 点以初速度v 1沿AB 方向平抛一小球,小球将击中坑壁上的最低点D 点;若A 点小球抛出的同时,在C 点以初速度v 2沿BA 方向平抛另一相同质量的小球并也能击中D 点。
上海市闸北区2015届高三下学期期中练习英语试题2015.4I. Listening Comprehension(30分)Section ADirections: In Section A, you will hear ten short conversations between two speakers. At the end of each conversation, a question will be asked about what was said. The conversation and the question will be spoken only once. After you hear a conversation and the question about it, read the four possible answers on your paper, and decide which one is the best answer to the question you have heard.1.A. She should watch on her weight.B. She can sometimes eat at will.C. She is already overweight.D. She should avoid sweet food.2. A. At the Emergency Room.B. At the grocery store.C. At the dentist’s.D. At a decade-old toast shop.3. A. 20. B. 30. C. 35. D. 45.4. A. On the phone. B. By text. C. Online. D. Face to face.5. A. Furniture shop assistant. B. House agent.C. Insurance agent.D. Carpenter.6. A. Tickets bought online are cheaper.B. It’s hard to buy the tickets at the box office.C. Free pamphlets provide discounts for the Ballet.D. The Ballet show could be watched online.7. A. There are all together three sections for the exam.B. She failed to finish the exam within time.C. She was poor at multiple choices.D. She performed well in the physics exam.8. A. It is too expensive a trip.B. It’s a pity he can’t take his family with him on the trip.C. The trip takes too much time.D. He doesn’t enjoy going to New Zealand for a trip.9. A. Stay up late for exams.B. Don’t pay too much attention to exams.C. Study hard throughout the term.D. Give up on the math test.10. A. Relaxed B. Calm. C. Excited. D. Nervous.Section BDirections: In section B, you will hear two short passages, and you will be asked three questions on each of the passages. The passages will be read twice, but the questions will be spoken only once. When you hear a question, read the four possible answers on your paper and decide which one would be the best answer to the question you have heard.Questions 11 through 13 are based on the following passage.11. A. Relationship problems.B. Low working productivity.C. Poor income.D. Depression.12. A. 6%. B. 10%. C. 15%. D. 26%.13. A. The poor treatment received from National Health Service.B. Patients’ inability to go to bed with a teddy bear.C. The bad quality of the mattress patients use.D. The tension they suffer from in lives.Questions 14 through 16 are based on the following passage.14. A. Because they were in need of clothes and food.B. Because they wanted to find honey.C. Because they wanted to take revenge.D. Because they intended to occupy the village.15. A. Because they migrated from Africa.B. Because they are a rare group surviving on the Andamans.C. Because they store precious honey.D. Because their DNA is valuable for scientific study.16. A. They want to learn local language.B. They come to see the outside world.C. They are chasing away outsiders.D. They need drinks and cigarettes.Section CDirections: In section C, you will hear two longer conversations. The conversations will be read twice. After you hear each conversation, you are required to fill in the numbered blanks with the information you hear.Blanks 17 through 20 are based on the following conversation:Blanks 21 through 24 are based on the following conversation:II. Grammar and VocabularySection ADirections: Read the following two passages. Fill in the blanks to make the passage coherent. For the blanks with a given word, fill in each blank with the proper form of the given word. For the other blanks, fill in each blank with one proper word. Make sure that your answers are grammatically correct.(A)Being skinny is not beautiful but being healthy is. Most young people, unfortunately, (25)______(convince) that being thin, and therefore being stylish is a major way of maintaining self-worth. To make the matter worse, they might take this so far that they are likely to end up (26)______ eating disorders.Eating disorders are psychological illnesses defined by abnormal eating habits, (27)______ may involve either insufficient or too much food intake to the damage of an individual's physical and mental health. Bulimia nervosa(暴食症) and anorexia nervosa(食欲匮乏)are the(28)______(common) forms of eating disorders.(29)______ diagnosed with anorexia nervosa are well under a healthy bodyweight. But patients with bulimia nervosa may have a body weight that falls within the range from normal tooverweight. (30)_____ primarily thought of as affecting females, eating disorders influence males as well.The precise cause of eating disorders is not entirely understood, but (31)______ is agreed that the disease is linked to other medical conditions and situations. Besides, cultural idealization of thinness and youthfulness also contributes to (32)______(reduce) weight forcefully. The problem has affected a large population worldwide.(B)A new report said middle class workers could still be working (33)______ ______ they are at the age of 70, to help out their grown up children.Middle class workers (34)______(age) 50 and above are being forced to delay their retirement, with many blaming their children, a report revealed yesterday.To many middle class workers, (35)______ bothered them from work couldn't compare with the possibility that they might postpone their retirement date by around five years.It is not just the rising cost of living that is causing the delay. Many pointed to the fact that they are constantly having to provide for their grown-up children at an age (36)______ they assumed they should be financially independent.Actually, one in five middle class workers (37)______ keep working in order to support their children. Many workers struggled all along to the retirement date, only (38)______(realize) that they had to switch to a part-time working pattern, also called semi-retirement. Rarely (39)______ people hear of the concept of semi-retirement in the past but now semi-retirement has become the routine among wealthier people in their 50s and 60s, regarded as (40)______ sign of the country’s on-going worsening economy.Section BDirections: Complete the following passage by using the words in the box. Each word can be used only once. Note that there is one word more than you need.A drop in the sun's radiation can cause cold winters in parts of North America and Europe, scientists say, a finding that could improve long-range forecasts and help countries ___41___ for storms.Scientists have known for a long time that the sun has an 11-year cycle during which radiation from the sun reaches a(n) ___42___ then falls. But detecting a clear link of the cycle to the weather has proved much ___43___ ."Our research notices a link between solar activities and regional winter climate," lead author Sarah Ineson of the UK Met Office told the reporters in an email.Her team focused on the data from the recent minimum solar radiation period during 2008-10, which was a(n) ___44___ calm period for the sun but at the same time, ___45___ winters in the U.S and Europe were recorded which brought troubles to many businesses and made people’s lives difficult.The researchers found that a reduction in radiation from the sun can affect wind patterns , ___46___cold winters."While radiation levels won't tell us what the day-to-day weather will be, they provide the exciting ___47___of improved prediction for winter conditions for months and even years ahead. These predictions play an important role in long-term weather planning," Ineson said.Ineson's team used the data in a complex computer to ___48___ long-term weather patterns. It successfully reproduced what scientists had observed happening in the upper atmosphere during changes in solar radiation. More study was needed, though. The key ___49___ in the experiment lay in the satellite data used, because it spans(跨度) only a few years. "So there are still questions concerning whether the current research results are accurate and whether they can be ___50___ to other solar cycles," she said.III. Reading ComprehensionSection ADirections: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context.Recently, Pew Research Center announced that over a quarter of Americans have shared a selfie online. Unsurprisingly, the practice of photographing oneself and sharing that image via social media has ___51___ among all age groups. Evidence of its mainstream nature is seen in other aspects of our culture too. Last year, "selfie" was not only added to the Oxford English Dictionary, but also named Word of the Year.Yet, despite the huge number of people practicing it, ___52___ is also surrounding selfie. An assumption that sharing selfies is embarrassing runs throughout the journalistic and scholarly coverage on the topic. Negative words like "self-centered" and "___53___" have inevitably become a part of any conversation about selfies among scholars.But, over a quarter of all Americans are relying on it. Why? The usual reasons given by scholars—self-center and fame-seeking—seem too ___54___ to explain such a crowd acting. There is always more to a social cultural practice than what ___55___.Simply put, physical and digital technology make it possible. The idea that technology ___56___ the social world and our lives has been recognized by people. To some extent, world is shaped by technological revolutions. The selfie is not a(n) ___57___ form of expression. Artists have created self-portraits for centuries, from cave to oil paintings, to early photography and modern art. People are ___58___ their feelings and thoughts through certain media. What's original about today's selfie is its public popularity. Technological advancement ___59___ the self-portrait used to be restricted to the art world and gave it to the masses. Those digital front-facing cameras, social media platforms, and wireless communications conveniently available make selfie a job ___60___ any time anywhere.Besides, We are not ___61___ beings living by ourselves. We are social beings who live in social communities, and as such, our lives are fundamentally formed by social relations with other people. As photos meant to be ___62___, selfies are not individual acts; they are social gestures.Selfies, as well as our presence on social media generally, are a part of “identity work"--the work that we do on a daily basis to ___63___ that we are seen by others as we wish to be seen. In fact, the crafting and display of identity has long been understood as a social process. The selfies we take and show are to present a ___64___ image of us so as to become a part of our identity formation and ___65___.51. A. flowered B. returned C. imposed D. functioned52. A. negotiation B. criticism C. regret D. punishment53. A. self-contained B. self-evident C. self-absorbed D. self-financed54. A. necessary B. smart C. certain D. shallow55. A. meets the eye B. takes the lead C. raises the alarm D. makes the point56. A. operates B. produces C. structures D. ruins57. A. advanced B. new C. intelligent D. available58. A. offering B. revising C. inspiring D. conveying59. A. liberated B. tagged C. honoured D. maintained60. A. at length B. with ease C. at large D. with regards61. A. isolated B. courageous C. traditional D. civilized62. A. saved B. shared C. updated D. deleted63. A. claim B. suppose C. ensure D. signal64. A. fashionable B. skillful C. mysterious D. particular65. A. summary B. evaluation C. monitoring D. exhibitionSection BDirections: Read the following three passages. Each passage is followed by several questions or unfinished statements. For each of them there are four choices marked A, B, C and D. Choose the one that fits best according to the information given in the passage you have just read.(A)Jack looked up and saw in the distance red and green navigation lights coming towards them and knew it must be a naval patrol(巡逻) boat because of its speed. As the humming of the boat’s powerful engines drew closer, Jack bent down.Jack then let out a frightened cry as the brilliant beam of a searchlight broke the darkness and swept the fishing boat from head to tail. By its reflected light, Jack could clearly see the similar looks on the faces of other bent ones.Jack knew that if the patrol boat came close enough, its men would surely see the people hidden in the fishing boat. To collect himself, he leaned his head a little so that he could see Derek standing in the head of the boat, holding the tiller(舵柄). Derek managed to wave back at the patrol boat as if he had not a care in the world. How imperturbable he was!Someone on board the patrol boat switched on a loud speaker and a voice, made harsh and thin by its horn, demanded,” Where are you bound?”Derek shrugged and shouted back, “Tell me where the fish run and I’ll tell you where I am bound.”The noise of idling engines drowned his voice.“Say again!” barked the speaker.“Anywhere where there’s fish!”Derek shouted back. There was a pause. The boats drifted closer to each other.“Why aren’t you showing navigation lights?”Jack watched as Derek pretended to look puzzled and leant out over the side as if to see what they said were true. “They must have blown out,” he apologized with a shrug. “I’ll light them again as soon as you stop rocking me about like this.”Aboard the patrol boat, the captain was wondering if it would be worthwhile searching this old fishing boat for stowaways as how many breathing souls could such a shabby boat hide? The radio suddenly cackled. Abruptly, without another word being exchanged, the light went out and the patrol boat started its engines, speeding off into the dark, leaving the fishing boat floating about in the water.66. Jack let out a scared cry because he ______.A. saw something in the seaB. was afraid of being discoveredC. was blinded by the bright lightsD. was scared by the faces of companions.67. The patrol boat captain did not search the fishing boat as he ______.A. didn’t find it worthwhileB. looked down upon the shabby old fishing boatC. trusted Derek very much.D. was called to another place via the radio68. The underlined word “imperturbable” in the passage is closest in meaning to ______.A. anxiousB. nervousC. calmD. sociable69. Which of the following statements is TRUE according to the passage?A. Derek didn’t realize that Jack and others hid in the fishing boat.B. The captain was suspicious of what Derek told him.C. The patrol boat approached the fishing boat to inspect illegal goods.D. Derek succeeded in covering up for the Jack and others on the boat.(B)70. The two places of interest that enjoy high temperatures are ______.A. Tucson and NewfoundlandB. Grenada and GrimseyC. Newfoudnland and CuencaD. Tucson and Cuenca71. The creature(s) mentioned in the booklet that is not afraid of cold weather is ______.A. uropygialis birdsB. whales and seabirdsC. puffin birds.D. hunting dog72. Cuenca’s major tourist attraction is ______.A. the hanging rocky face of an art museumB. a naturally formed castleC. the famous bakery in the summer timeD. a wooden pedestrian swinging bridge73. Which of the following statements is TRUE according to the booklets?A. There are no people living in Grimsay due to the extreme whether.B. Grenada would especially appeal to the cooking fans.C. The most impressive focus of attraction in Southern Belize is the Blue Hole.D. People’s safety in Tucson can’t be guaranteed by the local government.(C)Trade has a pretty bad name in some quarters. Trade robs poor people of a proper living, and keeps them trapped in poverty. There is a widely held popular view that trade is unfair.Though many claim that a freer trade would change the current indecent reputation of world market, the cure-all free trade is the dream of most textbook economists. In fact, "Free trade" has been used successfully by powerful countries to land their mass-produced goods on fresh overseas dumping grounds and squeeze out local household businesses and craftsmanship.At home the story is different. Large firms have little appetite for free trade and competition in their own backyard. They prefer to enjoy the advantages and protections for which they have carefully earned. Free thus fierce competition has little appeal for those who understand that they will make more profit if they can corner the market, whether at home or abroad.By contrast, making trade fairer is about addressing both outcomes and processes of trade. Fairness is not just moral request. It affects behaviour. Actually the concept of fairness increases steadily as societies achieve greater market uprightness: Businessmen from upright societies are willing to punish those who do not play fair, even if this is costly to themselves.Fairer trade rather than freer trade could partly mend mal-administering of resources in certain areas. Though thought of as evil economic policies in the west world, carefully planned special preferences and protectionism could be used intelligently to help to block the economic robbery of the rich class in African countries, and to improve the lives of the bottom billion.Fairness is also important in the control of trade. The current International trade negotiations have resulted in rules favouring the powerful. The rules are made in negotiations in which the countries in control call the shots, and do not always do so in good faith. Industrialized countries were often found to have obtained definite and far-reaching commitments from developing countries, in exchange for vague promises, such as to liberalise agriculture, which they have not kept. On the other hand, the essence of the fair trade lies in the promise that every party benefit from the business, rich or poor, powerful or weak.Making trade fairer is important to avoid a further public hate against trade. It is also important so as better to balance trade goals with other important national goals such as environmental and social protection. Finally, the so-called free trade system needs to be made fairer so that it does not block competition, and crush innovation and business spirit. It needs to offer a more level playing field to commercial newcomers and competitors in rich and poor countries alike.74. Free trade is a conc ept at rich countries’ service to ______.A. open up new markets abroadB. define trade in the economic textbooksC. dump pollutants in poor countriesD. learn the skills from local household businesses.75. The key mechanism of fair trade is ______.A. punishing the rich countries when they cheat the poor countriesB. making sure that rich countries provide more chances for poor countriesC. promoting special preferences and protectionism in poor areasD. guaranteeing the common interests of all the dealers76. The underlined word “mal-administering” in the passage is closest in meaning to ______.A. macro-managementB. overall collectionC. uneven distributionD. negative mining77. Which of the following statements is TRUE according to the passage?A. Large firms earn huge profits from free trade on domestic markets.B. Honest dealers would sacrifice their own interest to discipline the dishonest.C. Special preferences and protectionism are occasionally adopted in western countries.D. A fairer trade helps to ease competition between the rich and the poor.Section CDirections: Read the passage carefully. Then answer the questions or complete the statements in the fewest possible words.Few would argue that there has not been significant technological progress in the field of self-driving cars in recent years. Aside from the technology question, the legislative issue gives the world a worse headache. The content of the trouble centres on the question of who is to blame in a crash. The legal field tends to have the owners take responsibility for the messes their cold lifeless machine makes, for which case an explosion of lawsuits are well expected.Today, many of the car manufacturers and their suppliers are researching self-driving technology, but it is unclear why they would want to roll it out quickly. A consumer in America, for example, uses his or her car for approximately one hour per day. There is, therefore, a large amount of "free capacity" in the personal vehicle use market. Imagine a world where you can be driven to work, and where your car can then turn around and drive home so that your partner or anybody else can use it during the day. This shared use pattern could certainly stop the need to own a second car. Taken to its logical conclusion, it could even be the biggest reason to eliminate the need to own a car at all. The effects on car sales volumes could be destructive.The possible violation of privacy is also a big issue on the map. We all know that consumer data is big business. A self-driving car would easily log where you visited, the time of the day you went, and much more. Though your purchase preferences might escape secret peeping, the leakage of your whereabouts seems inevitable as it’s hard to do what you are alw ays doing to your smartphone toward the sole tool of transportation. Power off the big steel fellow and you are stuck on the road. The now excitedly expecting public are sure to be annoyed soon.Much discussed, the poor application of the technology outweighs the previous factors. In car industry, new vehicle features take a long time to get to broad market mass. Features are typically launched first on high-end vehicles, and then trickle down once there is sufficient space in the market to generate the scale affordable for the volume vehicles. With a car model's life cycle being between five and seven years, it is hard to see self-driving technology being fitted as standards of the mass-market brands.We still have a long way off from a world of completely self-driving cars.(Note: Answer the questions or complete the statements in NO MORE THAN EIGHT WORDS.)78. The likelihood to take the car owners as the guilty party in traffic accidents will give rise to ______.79. What feature of the self-driving car would mainly affect car sales?80. How can we prevent our personal data from being monitored by the self-driving car?81. The most serious problem facing the self-driving car is _______.II卷(共47分)I. Translation(22分)Directions: Translate the following sentences into English, using the words given in the brackets.1.语言运用需要足够的词汇量为基础。
闸北区2015学年度第二学期期中练习卷八年级物理试卷(2016.4)(满分100分,考试时间60分钟)考生注意:1.本试卷含五个大题。
2.答题时,考生务必按答题要求在答题纸规定的位置上作答,在草稿纸、本试卷上答题一律无效。
一、选择题(共16分)下列各题均只有一个正确选项,请将正确选项的代号用2B铅笔填涂在答题纸的相应位置上,更改答案时,用橡皮擦去,重新填涂。
1.短跑运动员奔跑时的速度最接近A.1千米/时 B.1米/秒 C.10千米/时 D. 10米/秒2.用手拿着两个鸡蛋,所用的力最接近A.1牛 B.10牛 C.100牛 D. 1000牛3.在各种不同色光中,叫做三原色光的是A.红、黄、蓝 B.红、绿、蓝 C.红、橙、蓝 D.红、白、蓝4.跳远或跳高运动员都是先跑一段距离才起跳,这是为了A.增大惯性 B.减小惯性 C.克服惯性 D.利用惯性5.用凸透镜观察书本上的一行小字,可以看到正立放大的像,如果透镜与书本的距离为8厘米,则该凸透镜的焦距可能为A. 10厘米 B.8厘米 C.6厘米 D.3厘米6.如图l所示,拉力F经过滑轮B使物体沿水平方向做匀速直线运动,如果物体与水平面间的滑动摩擦力大小为30牛,不计绳与滑轮间的摩擦,则拉力F的大小为A. 60牛 B.30牛 C.15牛 D. 10牛7.汽车在平直的公路上作匀速直线运动,关于汽车的力中属于平衡力的是A.汽车受到的重力与汽车对地面的压力B.汽车受到的摩擦阻力与汽车受到空气的阻力C.汽车受到向前的动力与汽车受到向后的阻力D.汽车受到的重力与汽车受到向后的阻力8.生活中利用杠杆原理的工具极为常见,观察图2所示,属于费力杠杆的是二、填空题(共34分)请将结果填入答题纸的相应位置。
9.物理学中,把一个物体相对于另一个物体的位置变化叫做 (1) ,简称运动,宇宙中的一切物体都在 (2) 。
10.汽车在马路上作匀速直线运动,以路旁的树木为参照物,汽车是 (3) 的,若以车上坐着的乘客为参照物,汽车是(4)的。
b c专题八、电场和磁场(B 卷)一、单项选择题(每小题 2 分)。
1、关于元电荷,下述正确的是 D(A)点电荷就是元电荷(B)元电荷就是正电子(C)元电荷是带电量为 1C 的电荷(D)自然界中已知的最小电荷量2、下列选项中,会导致静电危害的是 B(A)建筑物屋顶安放避雷针(B)印染厂车间保持空气干燥 (C)赛车轮胎采用导电橡胶制成 (D)高档的地毯中夹一些不锈钢丝3、下列哪些物理量与检验电荷无关(D)(A )电场强度 电势 电功(B )电场力 电势差 电势能 (C )电场力 电势能 电功 (D )电势差 电场强度 电势二、单项选择题(每小题 3 分)4、如图甲,Q 1、Q 2 为两个固定着的点电荷,a 、b 是它们连线的延长线上的两点。
现有一点电荷,只在电场力作用下,以一定的初速度沿直线从a 点开始经 b 点向远处运动,其 υ-t 图像如图乙,电子经过 a 、b 两点的速度分别为 υa 、υb ,则 C(A)(A) Q 1 一定带正电(B) Q 1 的电量一定小于 Q 2 的电量 (C) b 点的电场强度一定为 0(D)电子的电势能先增大后减小Q 1 Q 2甲a bυbυaυ乙 t5、如图,两个带电小球 A 、B ,都用长 L 的绝缘丝线悬挂在 O 点,小球 A 恰好在 O 点正下方,且靠着光滑绝缘竖直墙。
静止时,A 、B 相距为 d 。
为使 AB 间距离减为保持平衡状态,可采用的方法是 AOd 2时,仍(A)将 B 的质量增加到原来的 8 倍(B)将 A 、B 的质量都增加到原来的 4 倍(C)将 A 、B 的电荷量都减小到原来的一半(D)将 A 、B 的电荷量都增加到原来的 2 倍LALd B6、如图,某示波管内的聚焦电场,上下对称分布的实线和a虚线分别表示电场线和等势线,一电子分别在 a 、 、 三点,所受的电场力为 F 、F 和 F ,所具有的电势能为 E ,E ,bab c a bE ,则他们的大小关系是 DcA . F a > F c , E a < E cB . F a > F b ,c2E > EabC . F b < F c , E b < E cD . F b > F c ,E b > E c7、如图所示,虚线 AB 和 CD 分别为椭圆的长轴和短轴,相交 于 O 点,两个等量异号点电荷分别位于椭圆的两个焦点 M 、N C上。
2015届高三毕业班物理第二次质量检测(相互作用A卷)考生注意:1. 本试卷分第I卷(选择题)和第II卷(非选择题)两部分,共1OO分.考试时间90分钟.,2. 请将各题答案填在试卷后面的答题纸上.第I卷(选择题共42分)选择题(共14小题.在每小题给出的四个选项中,有的小题只有一个选项正确,有的小题有多个选项正确;全部选对的得3分,选对但不全的得2分,有选错或不答的得0分)1、一根轻绳的上端悬挂在天花板上,下端挂一灯泡,则:A.灯泡受的重力和灯泡对绳的拉力是一对平衡力B.灯泡受的重力和绳对灯泡的拉力是一对作用力和反作用力C.灯泡对绳的拉力和绳对灯泡的拉力是一对作用力和反作用力D.绳对天花板的拉力和天花板对绳的拉力是一对平衡力2、图中AO、BO、CO是完全相同的三条绳子,将一根均匀的钢梁吊起。
当钢梁足够重时,结果AO先断,则()A. α=120°B.α< 120°C. α> 120°D.不能确定3、在粗糙水平地面上放着一个截面为半圆的柱状物体A,A与竖直墙之间放一光滑半圆球B,整个装置处于平衡状态。
已知A、B两物体的质量分别为M和m,则下列说法正确的是A.A物体对地面的压力大小为MgB.A物体对地面的压力大小为(M+m)gC.B物体对A物体的压力小于mgD.A物体对地面的摩擦力可能大于mg4、一根大弹簧内套一根小弹簧,大弹簧比小弹簧长0.20 m,它们的下端固定在地面上,而上端自由,如图甲所示。
当加力压缩此组合弹簧时,测得力和弹簧压缩距离之间的关系如图乙所示,则两弹簧的劲度系数分别是(设大弹簧劲度系数为k1,小弹簧劲度系数为k2)()A. k1=l00 N/m, k2=200 N/mB. k l=200 N/m, k2=100 N/mC. k1=100 N/m, k2=300 N/mD .k 1=300 N/m ,k=200 N/m5、如图所示,质量为m 的物体置于倾角为θ的固定斜面上.物体与斜面之间的动摩擦因数为μ,先用平行于斜面的推力F 1作用于物体上使其能沿斜面匀速上滑,若改用水平推力F 2作用于物体上,也能使物体沿斜面匀速上滑,则两次的推力之比F 1F 2为( )A .cos θ+μsin θB .cos θ-μsin θC .1+μtan θD .1-μtan θ6、如图所示,物体A 、B 用细绳与弹簧连接后跨过滑轮.A 静止在倾角为45°的粗糙斜面上,B 悬挂着.已知质量m A =3m B ,不计滑轮摩擦,现将斜面倾角由45°减小到30°,那么下列说法中正确的是 ( ).A .弹簧的弹力将减小B .物体A 对斜面的压力将减少C .物体A 受到的静摩擦力将减小D .弹簧的弹力及A 受到的静摩擦力都不变7、如图所示,F 1、F 2为有一定夹角的两个力,L 为过O 点的一条直线,当L 取什么方向时,F 1、F 2在L 上分力之和为最大( )(A )F 1、F 2合力的方向, (B )F 1、F 2中较大力的方向, (C )F 1、F 2中较小力的方向, (D )以上说法都不正确。
某某市闸北区2015学年度第二学期高三物理学科期中练习卷〔2016.4〕本试卷共8页,总分为150分,考试时间120分钟。
全卷包括六大题,第一、二大题为单项选择题,第三大题为多项选择题,第四大题为填空题,第五大题为实验题,第六大题为计算题。
考生注意:1、答卷前,务必用钢笔或圆珠笔在答题纸正面清楚地填写姓名、某某号。
2、第一、第二和第三大题的作答必须用2B铅笔涂在答题纸上相应区域内与试卷题号对应的位置,需要更改时,必须将原选项用橡皮擦去,重新选择。
第四、第五和第六大题的作答必须用黑色的钢笔或圆珠笔写在答题纸上与试卷题号对应的位置〔作图可用铅笔〕。
3、第30、31、32、33题要求写出必要的文字说明、方程式和重要的演算步骤。
只写出最后答案,而未写出主要演算过程的,不能得分。
有关物理量的数值计算问题,答案中必须明确写出数值和单位。
一.单项选择题〔共16分,每一小题2分,每一小题只有一个正确选项。
〕1.在杨氏双缝干预实验中,如下说法正确的答案是 ( )〔A〕用红光作为光源,屏上将呈现红黑相间的条纹〔B〕用白光作为光源,屏上将呈现黑白相间的条纹〔C〕用紫光作为光源,中央明条纹宽度是两边条纹宽度的2倍〔D〕在实验装置不变的情况下,红光条纹间距小于蓝光的条纹间距2.符合发现和完善万有引力定律历史事实的是( )〔A〕哥白尼提出三大行星定律〔B〕卡文迪什提出“地心说〞〔C〕牛顿承受了胡克等科学家关于“吸引力与两中心距离的平方成反比〞的猜测〔D〕开普勒根据大量实验数据得出了比例系数G的大小3.科学实验在物理学开展中起到了非常重要的作用,如下说法正确的答案是〔〕〔A〕卢瑟福通过 粒子散射实验证实了在原子核内部存在质子〔B〕查德威克仔细地研究了γ射线,从中发现了中子〔C〕汤姆孙通过一系列关于阴极射线的实验,发现了电子〔D 〕贝克勒尔通过对天然放射现象的研究,发现了原子中存在原子核4.如下与α粒子相关的说法中正确的答案是 ( )〔A 〕天然放射现象中产生的α射线速度与光速相当,穿透能力很强〔B 〕23892U 〔铀238〕核放出一个α粒子后就变为23490Th 〔钍234〕〔C 〕高速α粒子轰击氮核可从氮核中打出中子,核反响方程为4141612780He+N O+n〔D 〕丹麦物理学家玻尔用α粒子轰击氮核,第一次实现了人工转变5.如下关于光电效应的说法中正确的答案是 〔 〕〔A 〕普朗克提出了“光子说〞这一科学假说〔B 〕发生光电效应时,从金属外表逸出的光电子速度大小均相等〔C 〕用一束紫外线照射锌板,和锌板相连的验电器指针发生偏转,说明锌板带负电〔D 〕发生光电效应时,单位时间里照射到金属外表的光子数越多,单位时间内逸出的光电子数越多6.某质点的振动图像如图,如下说法正确的答案是〔 〕〔A 〕质点的振动周期为2s〔B 〕2s 末质点的速度为零〔C 〕0~1s 内质点做匀减速运动 〔D 〕在1.5s 和2.5s 末,质点的速度一样,加速度不同7.一定质量的理想气体,在经历如图从a 到b 状态变化过程中〔 〕〔A 〕气体的内能变小〔B 〕气体分子的平均距离增大〔C 〕每一个气体分子的动能都在增大〔D 〕气体分子对单位面积上容器器壁的撞击力增大8.碘131的半衰期约为8天,假设某药物含有质量为m 的碘131,经过16天,该药物中碘131的含量大约还有 〔 〕〔A 〕m /4〔B 〕3m /4〔C 〕m /2〔D 〕m /16二.单项选择题〔共24分,每一小题3分,每一小题只有一个正确选项。
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闸北区2015学年度第二学期期中练习卷高三年级生命科学2016.4考生注意:1.试卷满分150分,考试时间120分钟。
2.本试卷分为第Ⅰ卷和第Ⅱ卷两部分.全卷共13页。
3.选择题的作答必须用2B铅笔涂在答题纸相应的区域,综合题作答必须用钢笔或圆珠笔将答案填写在答题纸与试.........,写在试卷上一律不给分。
...........卷题号对应的位置上一、选择题(共60分,每小题2分。
每小题只有一个正确选项)1.下列关于细胞中元素和化合物的叙述,不正确...的是A.糖类、脂肪、磷脂是由C、H、O三种元素组成的B.如果一种生物的核酸只由四种核苷酸组成,则该生物一定不是细胞生物C.mRNA、tRNA、rRNA都参与蛋白质的合成D.组成纤维素、淀粉和糖原的单体都是葡萄糖2.下列生物或结构的化学成分最相似的是A.烟草花叶病毒和染色体 B.噬菌体和染色体C.核糖体和染色体 D.噬菌体和中心体3.下列有关细胞器的说法正确的是A.核糖体是噬菌体、细菌、酵母菌唯一共有的细胞器B.线粒体是有氧呼吸的主要场所,在其中生成的产物有丙酮酸、二氧化碳和水C.洋葱鳞茎外表皮细胞中,具有双层膜的细胞器能利用光能合成糖类D.在机体免疫反应中,浆细胞内高尔基体活动会加强4.下列对生物体内ATP的叙述中,正确的是A.ATP中的能量可以来源于光能、化学能B.在有氧呼吸产生ATP的过程中,一定伴随着氧气的消耗C.ATP中的“A"与构成DNA、RNA中的碱基“A”是同一种物质D.人在短跑等剧烈运动时,骨骼肌细胞中每个葡萄糖分子生成ATP的量与安静时相等5.下列有关实验问题的叙述,不.正确..的是A.物镜测微尺每小格长度为10微米,可用来直接测量细胞的大小B.引流法操作是在盖玻片的一侧滴加试剂,在另一侧用吸水纸吸,并重复几次C .脊蛙反射实验需要自身对照D .用龙胆紫染色可以区分颤藻和水绵细胞6.下列哪项不.是玉米、蓝藻和变形虫细胞共有的 A .进行转录和翻译 B .进行细胞有丝分裂C .含有核糖体D .选择性地吸收和排出物质7.下列关于生物进化和生物多样性的描述正确的是A .变异在长期自然选择的作用下积累定能产生新的生物类型B .不同区域内,其生物物种数越多,辛普森指数也一定越高C .任何基因频率的改变,不论其变化大小如何,都属于进化的范畴D .抗药性强的害虫所产生的后代都具有很强的抗药性8.图1表示为小肠绒毛上皮细胞对不同物质的转运(转运的方向由箭头表明,符号的数量代表每种物质的浓度)。
一、填空题:(60分)本大题共有10题,要求在答题纸相应题序的空格内直接填写结果,每个空格填对得6分,否则一律得零分。
1。
设幂函数()f x 的图象经过点()8,4,则函数()f x 的奇偶性为____________. 【答案】偶函数考点:幂函数的定义、函数的奇偶性. 2.设复数122,12zi z i =+=+,在复平面的对应的向量分别为,OA OB ,则向量AB 对应的复数所对应的点的坐标为____________.【答案】(1,1)- 【解析】试题分析:∵复数122,12zi z i =+=+,∴(2,1)OA =,(1,2)OB =,∴(1,1)AB OB OA =-=-, ∴向量AB 对应的复数所对应的点的坐标为(1,1)-. 考点:向量的减法。
3。
已知定义域为R 的函数()y f x =的图象关于点()1,0-对称,()y g x =是()y f x =的反函数,若120x x +=,则()()12g x g x +=___________.【答案】—2 【解析】试题分析:∵函数()y f x =的图象关于点()1,0-对称,()y g x =是()y f x =的反函数,∴()y g x =关于点(0,1)-对称,∵120x x+=,∴21x x =-,∴()()()()12112g x g x g x g x +=+-=-。
考点:反函数、函数的对称性。
4。
一个篮球运动员投篮一次得3分的概率为a ,得2分的概率为b ,不得分的概率为c ,其中,,(0,1)a b c ∈.已知投篮一次得分的期望是2,则ab 的最大值是____________. 【答案】16【解析】试题分析:由题意可得: X 0 2 3 P c b a∵投篮一次得分的期望是2,∴232b a +=,∴211321(23)()6626a b ab b a +=⨯≤=,当且仅当23b a =时取“="。
考点:期望、均值定理.5。
高中数学学习材料马鸣风萧萧*整理制作闸北区2015学年度第二学期高三数学(理、文合卷)期中练习卷考生注意:1. 本次测试有试题纸和答题纸,解答必须在答题纸上,写在试题纸上的解答无效.2. 答卷前,考生务必在答题纸上将姓名、学校、考试号,以及试卷类型等填写清楚,并在规定区域内贴上条形码.3. 本试卷共有18道试题,满分150分.考试时间120分钟.一、填空题(60分)本大题共有10题,要求在答题纸相应题序的空格内直接填写结果,每个空格填对得6分,否则一律得零分.1.设函数()(01x xf x a a a a -=+>≠且),且(1)3f =,则(0)(1)(2)f f f ++的值是 .2.已知集合{||2|}A x x a =-<,2{|230}B x x x =--<,若B A ⊆,则实数a 的取值范围是 .3.如果复数z 满足||1z =且2z a bi =+,其中,a b R ∈,则a b +的最大值是 . 4.(理 )在直角坐标系xoy 中,已知三点(,1),(2,),(3,4)A a B b C ,若向量OA ,OB 在向量OC 方向上的投影相同,则34a b -的值是 .(文)已知x 、y 满足5003x y x y x -+≥⎧⎪+≥⎨⎪≤⎩,若使得z ax y =+取最大值的点(,)x y 有无数个,则a的值等于 .5.(理)某科技创新大赛设有一、二、三等奖(参与活动的都有奖)且相应奖项获奖的概率是以a 为首项,2为公比的等比数列,相应的奖金分别是以7000元、5600元、4200元,则参加此次大赛获得奖金的期望是 元.(文))在直角坐标系xoy 中,已知三点(,1),(2,),(3,4)A a B b C ,若向量OA ,OB 在向量OC 方向上的投影相同,则34a b -的值是 .6.已知1F 、2F 是椭圆2222:1(0)x y C a b a b+=>>的两个焦点,P 为椭圆上一点,且12PF PF ⊥,若12PF F ∆的面积为9,则b = .7.ABC ∆中,,,a b c 分别是,,A B C ∠∠∠的对边且222ac c b a +=-,若ABC ∆最大边长是7且sin 2sin C A =,则ABC ∆最小边的边长为 .8.(理)在极坐标系中,曲线sin 2ρθ=+与sin 2ρθ=的公共点到极点的距离为_________.(文)设等差数列{}n a 的公差为d ,若1234567,,,,,,a a a a a a a 的方差为1,则d = .9.(理)如右图,A 、B 是直线l 上的两点,且2AB =,两个半径相等的动圆分别与l 相切于A 、B 两点,C 是这两个圆的公共点,则圆弧AC ,圆弧CB 与线段AB 围成图形面积S 的取值范围是 .(文)已知函数2cos ,||1()21,||1xx f x x x π⎧≤⎪=⎨⎪->⎩,则关于x 的方程2()3()20f x f x -+=的实根的个数是 个.10.(理)设函数2()1f x x =-,对任意⎪⎭⎫⎢⎣⎡+∞∈,23x ,24()(1)4()x f m f x f x f m m ⎛⎫-≤-+⎪⎝⎭恒成立,则实数m 的取值范围是 . (文)设函数1()f x x x=-,对任意[1,)x ∈+∞,()()0f mx mf x +<恒成立,则实数m 的取值范围是 .二、选择题(15分)本大题共有3题,每题都给出四个结论,其中有且只有一个结论是正确的,必须把答题纸上相应题序内的正确结论代号涂黑,选对得5分,否则一律得零分. 11.(理)已知a 与b 均为单位向量,其夹角为θ,则命题:P ||1a b ->是命题5:[,)26Q ππθ∈的( )A .充分非必要条件B .必要非充分条件C .充分且必要条件D .非充分且非必要条件(文)若一个长方体共顶点的三个面的对角线长分别是,,a b c ,则长方体的对角线长是( )CBAlD 1 .A 1CEABCD B 1A .222a b c ++ B .2222a b c ++ C .ab bc ac ++ D .3(2)2b bc ac ++12.(理)已知,,,S A B C 是球O 表面上的点,SA ⊥平面ABC ,AB BC ⊥,1SA AB == 2BC =,则球O 的表面积等于( )A .π4B .π3C .π2D .π(文)已知a 与b 均为单位向量,其夹角为θ,则命题:P ||1a b ->是命题5:[,)26Q ππθ∈的( )A .充分非必要条件B .必要非充分条件C .充分且必要条件D .非充分且非必要条件13.已知数列{}n a 的前n 项和为n S ,对任意正整数n ,13n n a S +=,则下列关于{}n a 的论断中正确的是( )A .一定是等差数列B .一定是等比数列C .可能是等差数列,但不会是等比数列D .可能是等比数列,但不会是等差数列三、解答题(本题满分75分)本大题共有5题,解答下列各题必须在答题纸的规定区域(对应的题号)内写出必要的步骤.14.(理)(本题满分12分,第(1)小题5分,第(2)小题7分)在长方体1111ABCD A B C D -中,2AB =,1AD =,11AA =,点E 在棱AB 上移动. (1)探求AE 多长时,直线1D E 与平面11AA D D成45角;(2)点E 移动为棱AB 中点时,求点E 到平面11A DC 的距离.14.(文)(本题满分12分,第(1)小题5分,第(2)小题7分)如图几何体是由一个棱长为2的正方体1111ABCD A B C D -与一个侧棱长为2的正四棱锥1111P A B C D -组合而成. (1)求该几何体的主视图的面积;(2)若点E 是棱BC 的中点,求异面直线AE 与1PA 所成角的大小(结果用反三角函数表示).15.(本题满分14分,第(1)小题6分,第(2)小题8分)某公司生产的某批产品的销售量P 万件(生产量与销售量相等)与促销费用x 万元满足42+=x P (其中a x ≤≤0,a 为正常数).已知生产该批产品还需投入成本)1(6PP +万元(不含促销费用),产品的销售价格定为)204(P+元/件.(1)将该产品的利润y 万元表示为促销费用x 万元的函数; (2)当促销费用投入多少万元时,该公司的利润最大? 16.(本题满分15分,第(1)小题7分,第(2)小题8分)已知函数()sin()f x x ωϕ=+(0,0)ωϕπ><<的周期为π,图象的一个对称中心为π,04⎛⎫⎪⎝⎭.将函数()f x 图象上所有点的横坐标伸长到原来的2倍(纵坐标不变),再将所得到的图象向右平移2π个单位长度后得到函数()g x 的图象. (1)求函数()f x 与()g x 的解析式;A 1B 1C 1D 1ECBAPD .(2)(理)求证:存在0(,)64x ππ∈,使得0()f x ,0()g x ,00()()f x g x ⋅能按照某种顺序....成等差数列.(文)定义:当函数取得最值时,函数图像上对应的点称为函数的最值点,如果函数()3sinxy F x kπ==的图像上至少有一个最大值点和一个最小值点在圆222(0)x y k k +=>的内部或圆周上,求k 的取值范围.17.(本题满分16分,第(1)小题8分,第(2)小题8分)若动点M 到定点(0,1)A 与定直线:3l y =的距离之和为4. (1)求点M 的轨迹方程,并在答题卡所示位置画出方程的曲线草图;(2)(理)记(1)得到的轨迹为曲线C ,问曲线C 上关于点(0,)()B t t R ∈对称的不同点有几对?请说明理由.(文)记(1)得到的轨迹为曲线C ,若曲线C 上恰有三对不同的点关于点(0,)()B t t R ∈对称,求t 的取值范围.18.(本题满分18分,第(1)小题4分,第(2)小题6分,第(2)小题8分)已知数列{}n a ,n S 为其前n 项的和,满足(1)2n n n S +=. (1)求数列{}n a 的通项公式; (2)设数列1{}na 的前n 项和为n T ,数列{}n T 的前n 项和为n R ,求证:当2,*n n N ≥∈时1(1)n n R n T -=-;(3)(理)已知当*n N ∈,且6n ≥时有1(1)()32n mm n -<+,其中1,2,,m n =,求满足34(2)(3)n a n n n n n a ++++=+的所有n 的值.(文)若函数1()(1)31qx f x p =-⋅+的定义域为R ,并且lim ()0(*)n n f a n N →∞=∈,求证1p q +>.高三数学(理文合卷)期中练习卷参考答案一、填空题1、122、3a ≥3、24、(理)2;(文)1-5、(理)5000;(文)26、37、18、(理)13+;(文)12±9、(理)(0,2]2π-;(文)5 10、(理)32m ≤-或32m ≥;(文)1m <-二、11、B 12、(理)A ;(文)B 13、C三、14、(理)(本题满分12分,第(1)小题5分,第(2)小题7分) 解:(1)法一:长方体1111ABCD A B C D -中,因为点E 在棱AB 上移动,所以EA ⊥平面11AA D D ,从而1ED A ∠为直线1D E 与平面11AA D D 所成的平面角,1Rt ED A ∆中,145ED A ∠=12AE AD ⇒==. ……………………………5分法二:以D 为坐标原点,射线1,,DA DC DD 依次为,,x y z 轴轴,建立空间直角坐标系,则点1(0,0,1)D ,平面11AA D D 的法向量为(0,2,0)DC =,设(1,,0)E y ,得1(1,,1)D E y =-,由11sin4D E DC D E DCπ⋅=,得2y =,故2AE =(2)以D 为坐标原点,射线1,,DA DC DD 依次为,,x y z 轴,建立空间直角坐标系,则点(1,1,0)E ,1(1,0,1)A , 1(0,2,1)C ,从而1(1,0,1)DA =,1(0,2,1)DC =,(1,1,0)DE = …………3分 设平面11DA C 的法向量为(,,)n x y z =,由1100n DA n DC ⎧⋅=⎪⎨⋅=⎪⎩020x z y z +=⎧⇒⎨+=⎩ 令1(1,,1)2n =--,所以点E 到平面11A DC 的距离为n DE d n⋅=1=. …………4分14、(文)(本题满分12分,第(1)小题5分,第(2)小题7分)解:(1)画出其主视图(如下图),可知其面积S 为三角形与正方形面积之和. 在正四棱锥1111P A B C D -中,棱锥的高2h =,1224242S =⋅⋅+=+. ……………………………5分(2)取11B C 中点1E ,联结11A E ,11A E AE则11PA E ∠为异面直线AE 与1PA 所成角. 在11PA E ∆中,1115,2A E PA ==, 又在正四棱锥1111P A B C D -中,斜高为13PE =, 由余弦定理可得 114533cos 510225PA E +-∠==⋅⋅ ……………………6分所以113arccos 510PA E ∠=,异面直线AE 与1PA 所成的角为3arccos 510.………1分15、(本题满分14分,第(1)小题6分,第(2)小题8分) 解:(1)由题意知, )1(6)204(pp x p p y +--+= 将42+=x P 代入化简得: x x y 2322419-+-= (0x a ≤≤). ……………6分 (2)10)2(216322)2216(2322=+⨯+-≤+++-=x x x x y , 上式当且仅当2216+=+x x ,即2=x 时,取等号。
2015学年度第二学期高二年级期中考试卷物理合格考试(考试时间:60分钟满分:100分)一、单项选择题(每小题2分,共14分)1.如图,一个小球用两根轻绳挂于天花板上,球静止,绳1倾斜,绳2恰竖直。
则小球所受的作用力个数()2 A.一定是两个B.一定是三个1 C.不可能是二个D.可能是两个,也可能是三个2.下列叙述中符合物理学史实的有()A.汤姆生通过对伦琴射线的的研究,发现了电子,提出了原子的核式结构学说。
B.贝克勒尔发现了天然放射现象,从而认识到原子是可分的。
C.卢瑟福在原子核人工转变的实验中发现了原子核中存在质子和中子。
D.居里夫妇发现了两种放射性很强的元素钋和镭3.如图所示,用一根细绳和一根轻直杆组成三角支架,绳的一端绕在手指上,杆的一端顶在掌心,当A处挂上重物时,绳与杆对手指和手掌均有作用,对这两个作用力的方向判断完全正确的是右图中的( )A. B. C. D.4.如图所示,下列情况下线圈中不能产生感应电流的是()A.I增加a bIB.线圈向右平动- 1 -D.线圈以ab边为轴转动5.下列关于太阳系的说法正确的是()A.太阳系处在银河系的中心B.太阳系中只存在太阳和它的八大行星C.大阳系是由太阳和若干行星以及它们的卫星和慧星组成D.太阳系的能量来源于太阳内部重核裂变所释放的核能6.关于物体的运动,下面说法中不可能的是()A.加速度在减小,速度在增加B.加速度的方向始终变而速度不变C.加速度和速度大小都在变化,加速度最大时速度最小,速度最大时加速度最小D.加速度的方向不变而速度方向变化7.核反应堆是人工控制链式反应速度、并获得核能的装置。
它是由以下几个主要部件构成:(1)铀棒;(2)控制棒;(3)减速剂;(4)冷却剂。
关于控制棒的主要作用,下面说法正确的是()A.使快中子减速,维持链式反应的进行B.吸收中子,控制链式反应的速度C.冷却降温,控制核反应堆的温度不要持续升高D.控制铀的体积不要超过临界体积二、单项选择题(每小题3分,共24分)8.潮汐现象主要是由于月球对地球的不同部分施加不同的万有引力而产生的。
上海市闸北区2015学年度第二学期高三物理学科期中练习卷(2016.4)本试卷共8页,满分150分,考试时间120分钟。
全卷包括六大题,第一、二大题为单项选择题,第三大题为多项选择题,第四大题为填空题,第五大题为实验题,第六大题为计算题。
考生注意:1、答卷前,务必用钢笔或圆珠笔在答题纸正面清楚地填写姓名、准考证号。
2、第一、第二和第三大题的作答必须用2B 铅笔涂在答题纸上相应区域内与试卷题号对应的位置,需要更改时,必须将原选项用橡皮擦去,重新选择。
第四、第五和第六大题的作答必须用黑色的钢笔或圆珠笔写在答题纸上与试卷题号对应的位置(作图可用铅笔)。
3、第30、31、32、33题要求写出必要的文字说明、方程式和重要的演算步骤。
只写出最后答案,而未写出主要演算过程的,不能得分。
有关物理量的数值计算问题,答案中必须明确写出数值和单位。
一.单项选择题(共16分,每小题2分,每小题只有一个正确选项。
) 1.在杨氏双缝干涉实验中,下列说法正确的是( ) (A )用红光作为光源,屏上将呈现红黑相间的条纹 (B )用白光作为光源,屏上将呈现黑白相间的条纹(C )用紫光作为光源,中央明条纹宽度是两边条纹宽度的2倍 (D )在实验装置不变的情况下,红光条纹间距小于蓝光的条纹间距 2.符合发现和完善万有引力定律历史事实的是( ) (A )哥白尼提出三大行星定律 (B )卡文迪什提出“地心说”(C )牛顿接受了胡克等科学家关于“吸引力与两中心距离的平方成反比”的猜想 (D )开普勒根据大量实验数据得出了比例系数G 的大小3.科学实验在物理学发展中起到了非常重要的作用,下列说法正确的是() (A )卢瑟福通过α粒子散射实验证实了在原子核内部存在质子 (B )查德威克仔细地研究了γ射线,从中发现了中子 (C )汤姆孙通过一系列关于阴极射线的实验,发现了电子(D )贝克勒尔通过对天然放射现象的研究,发现了原子中存在原子核 4.下列与α粒子相关的说法中正确的是( )(A )天然放射现象中产生的α射线速度与光速相当,穿透能力很强(B )23892U (铀238)核放出一个α粒子后就变为23490Th (钍234)(C )高速α粒子轰击氮核可从氮核中打出中子,核反应方程为4141612780He+N O+n →(D )丹麦物理学家玻尔用α粒子轰击氮核,第一次实现了人工转变5.下列关于光电效应的说法中正确的是() (A )普朗克提出了“光子说”这一科学假说(B )发生光电效应时,从金属表面逸出的光电子速度大小均相等(C )用一束紫外线照射锌板,和锌板相连的验电器指针发生偏转,说明锌板带负电 (D )发生光电效应时,单位时间里照射到金属表面的光子数越多,单位时间内逸出的光电子数越多6.某质点的振动图像如图,下列说法正确的是() (A )质点的振动周期为2s (B )2s 末质点的速度为零 (C )0~1s 内质点做匀减速运动(D )在1.5s 和2.5s 末,质点的速度相同,加速度不同7.一定质量的理想气体,在经历如图从a 到b 状态变化过程中( ) (A )气体的内能变小 (B )气体分子的平均距离增大 (C )每一个气体分子的动能都在增大(D )气体分子对单位面积上容器器壁的撞击力增大8.碘131的半衰期约为8天,若某药物含有质量为m 的碘131,经过16天,该药物中碘131的含量大约还有() (A )m /4(B )3m /4(C )m /2(D )m /16二.单项选择题(共24分,每小题3分,每小题只有一个正确选项。
)9.探究波的形成过程中,某同学用手抓住绳子一端上下振动,形成了向右传播的波。
此波可看成简谐波,波的传播速度为v ,周期为T 。
下列说法正确的是() (A )简谐波的传播速度与振动的振幅有关 (B )绳中质点振动的速度等于波的传播速度(C )绳中相距为vT2的两个质点的振动位移总是相同(D )离手距离分别为x 1、x 2(x 2>x 1)的两个质点,开始振动的时间差为x 2-x 1v10.汽车发动机的额定功率为P 1,它在水平路面上行驶时受到的阻力f 大小恒定,汽车由静止开始作直线运动,最大车速为v 。
汽车发动机的输出功率随时间变化的图像如图。
下列说法正确的是() (A )开始时汽车牵引力恒定,t 1时刻牵引力与阻力大小相等 (B )开始时汽车牵引力逐渐增大,t 1时刻牵引力与阻力大小相等 (C )开始汽车做匀加速运动,t 1时刻速度达到v ,然后做匀速直线运动(D )开始汽车做匀加速直线运动,t 1时刻后做加速度逐渐减小的直线运动,速度达到v 后做匀速直线运动11.如图为两列沿绳传播的简谐横波(虚线表示甲波,实线表示乙波)在某时刻的波形图,M 为绳上x = 0.2m 处的质点,下列说法中正确的是()(A )M 点是振动加强点(B )图示时刻质点M 的速度为零 (C )甲波传播速度v 1大于乙波传播速度v 2(D )由图示时刻开始,再经1/4周期,M 将位于波峰12.如图,物体C 放在水平面上,物体B 放在C 上,小球A 和B 之间通过跨过定滑轮的细线相连。
若B 上的线竖直、两滑轮间的线水平,且不计滑轮的质量、滑轮轴上的摩擦、滑轮与线间的摩擦。
把A 拉到某位置(低于滑轮)由静止释放使A 在竖直平面内摆动,在A 摆动的过程中B 、C 始终不动。
下列说法中正确的是 ( ) (A )地面对C 的摩擦力有时不为零 (B )C 对B 的摩擦力有时有可能为零(C )C 对地面的压力有时可以等于B 、C 重力之和 (D )C 对B 的作用力有时竖直向上,有时竖直向下13.A 、B 两物体各自在不同纬度的甲、乙两处受到一个竖直向上的外力作用做变加速直线运动。
如图是物体A 、B 所受的外力F 与加速度a 的关系图线。
若物体A 、B 的质量分别为m A 、m B ,甲、乙两处的重力加速度分别为g A 、g B ,两个物体受到的重力分别为G A 、G B ,则()(A )m A >m B ,G A >G B (B )m A <m B ,G A <G B (C )m A >m B ,g A <g B (D )m A <m B ,g A >g B 14.如图,质量为m 的物块(可视作质点)置于粗糙水平面上的M 点,水平面的右端与固定的斜面平滑连接,物块与水平面及斜面之间的动摩擦因数相同。
开始时物块挤压弹簧使弹簧处于压缩状态,物块与弹簧未连接(弹簧自然伸长时不到M′点)。
现从M 点由静止释放物块,物块运动到N 点时恰好静止。
若在物块从M 点运动到N 点的过程中,物块与接触面之间由于摩擦所产生的热量为Q ,物块、弹簧与地球组成系统的机械能为E ,物块通过的路程为s 。
不计转折处的能量损失,下列图像正确的是( )(A ) (B ) (C ) (D )15.静电力常量k 用国际单位制的基本单位表示,正确的是 ( ) (A )N·m 2·C -2(B )kg·m 3·C -2·s -2(C )kg·A -2·m 3·s -2(D )kg·A -2·m 3·s -4 16.如图,长为L 、倾角为θ(θ<450)的光滑绝缘斜面处于电场中,一带电量为+q 、质量为m 的小球,以初速度v 0由斜面底端的A 点开始沿斜面上滑,到达斜面顶端的速度仍为v 0。
重力加速度为g 。
则( ) (A )小球在B 点的电势大于A 点的电势 (B )A 、B两点的电势差为qm gL(C )若电场是匀强电场,则该电场的场强最小值为tan mg qθ(D )若电场是带正电的点电荷产生的电场,则该点电荷不能放在C 点三.多项选择题(共16分,每小题4分。
每小题有二个或三个正确选项。
全选对的,得4分,选对但不全的,得2分;有选错或不答的,得0分。
)17.“套圈圈”是小孩和大人都喜爱的一种游戏。
小孩站立以速度v 1水平抛出圈圈并套取前方一物体,大人以速度v 2水平抛出圈圈并套取前方同一物体,则( ) (A )大人站在小孩同样的位置,且v 1>v 2 (B )大人站在小孩同样的位置,且v 1<v 2 (C )大人退后并下蹲至与小孩等高,且v 1>v 2 (D )大人退后并下蹲至与小孩等高,且v 1<v 218.图中K 、L 、M 为静电场中的三个相距很近的等势面。
一带电粒子射入此静电场中后,仅受电场力作用,沿a→b→c→d→e 轨迹运动。
下列说法中正确的是( ) (A )粒子在cd 段做加速运动 (B )粒子在c 点时电势能最大 (C )粒子在a 点与e 点的速率相等(D )K 、L 、M 三点的电势满足φK <φL <φM19.某跳伞队员从静止的直升机上跳下,先做自由落体运动,在t 1时刻,速度达到v 1时打开降落伞,做减速运动,在t 2时刻以速度v 2着地。
他的速度—时间图像如图。
下列说法正确的是( )(A )在t 1~t 2时间内,其平均速度v >v 1+v 22(B )降落伞打开后降落伞和跳伞队员所受的阻力越来越小K L M abc d e(C )若第一个跳伞队员跳下后,经过时间t 1,第二个跳伞队员跳下,则他们在空中的距离越来越大(D )若第一个跳伞队员跳下后,经过时间t 1,第二个跳伞队员跳下,则他们在空中的距离先增大后减小 20.如图甲,两条足够长的光滑平行金属导轨竖直放置,导轨间距为L 。
两导轨的上端接有电阻,阻值为R 。
虚线OO′下方存在垂直于导轨平面向里的匀强磁场,磁感应强度为B 。
现将质量为m 、电阻不计的金属杆ab ,从OO′上方某处由静止释放,金属杆在下落的过程中与导轨保持良好接触,且始终保持水平,不计导轨的电阻。
已知金属杆下落高度h 的过程中加速度a 与下落高度h 的关系图像如图乙,重力加速度为g 。
则( ) (A )金属杆下落h 的过程中,通过电阻R 的电荷量为BLh R(B )金属杆在磁场中的最大速度为22mgRB L(C )金属杆进入磁场时下落时间为22()m g a R gB L + (D )金属杆下落h 的过程中,回路中产生的热量为322442m g R mgh B L- 四、填空题(共20分,每题4分。
)本大题中第22题为分叉题,分A 、B 两类,考生可任选一类答题。
若两类试题均做,一律按A 类题计分。
21.用光的____________难以解释一束光射到两种介质分界面处会同时发生反射和折射(选填“微粒说”或“波动说”)。
目前认为光具有_______________。
22A 、22B 选做一题═══════════════════════════════════════════════════════ 22A .如图,两块相同平板P 1、P 2面上,质量均为m 。