【AP物理C】【真题】2002年力学解答题答案

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2002 理论力学

中国航天科研机构2002年招收攻读硕士学位研究生入学考试理论力学试题(共六题，总计：100分)一、(15分) 物块A重50N，B重100N，两者叠置如图1所示，且用细绳将物块A拴住。

已知A、B之间以及B与水平地面之间的静摩擦系数均为f=0.3，求能使物块B相对s于地面产生滑动的最小水平力F。

图1二、(20分) 两球C和D质量各为m，用直杆连接，并将其中点O固结在铅垂轴AB上，杆与轴的交角为α，杆的长度为l2，见图2。

(1) 如此杆绕AB轴以等角速度ω转动，求在下列不同情况下，质点系对AB轴的动量矩。

a) 杆重忽略不计；b) 杆为均匀的，质量为m2；(2) 若杆绕AB轴以等角加速度ε转动，摩擦力矩忽略不计，求上述两种情况下绕AB轴作用的力矩M分别为多少。

三、(20分) AB 杆两端与滑块以铰链连接，滑块可在各自的滑道中滑动，如图3所示。

已知杆长l =60cm ，MB =20cm ，滑块A 的运动规律为t π2sin 260S =(S 的单位为cm, t 的单位为s)。

试求：(1) 点M 的运动方程； (2) 当t =121s 时，点M 的速度。

图3四、(15分) 如图4，小环M 套在水平直线钢丝和形状为抛物线2ax y =的钢丝交点处，水平钢丝以匀速v 向上运动，求小环相对于水平钢丝运动的速度和加速度。

五、(15分) 如图5，重物M 的质量为1m ，鼓轮质量为2m ，半径为r ；鼓轮对其转轴的回转半径为ρ，斜坡的倾角为α。

如在鼓轮上作用一不变的力矩0M 将重物M 提升，求重物M 由静止开始沿斜坡上升路程为S 时的速度V(略去摩擦和绳子的质量)。

图5六、(15分) 如图6，小球M 的质量为m ，置于曲线2kx y =形状的光滑钢管中，设钢管绕铅垂轴oy 以匀角速度ω转动。

如欲使小球在此钢管中任何位置均能处于相对静止状态，求钢管绕铅垂轴oy 的转动角速率及钢管对小球的反作用力N 。

2017ap物理c力学真题答案

2017ap物理c力学真题答案一、单项选择题【答案】a考点：电磁感应现象与电流的磁效应现象分辨a.我国水资源是有限的，所以水能是不可再生能源b.发光二极管主要就是由超导材料制成的c.试电笔在使用时，试电笔上的任何金属都不要接触，否则会有触电危险d.工业上采用超音波探伤仪能够检查出来金属零件内部的裂纹【答案】 d【解析】我国水资源是有限的，但水能是可再生能源，a选项不正确;发光二极管是由半导体材料制成的，b选项不正确;使用试电笔时不能接触笔尖金属体，必须接触笔尾金属体，这样才能形成通路，c选项不正确;故d选项正确，选填d考点：再生能源辨识;发光二极管材料;试电笔的采用;超声波应用领域。

a.使用红外线传输数字信号b.使用超声波传输数字信号c.采用光纤传输数字信号d.采用电磁波传输数字信号【答案】d一、单项选择题a.电路中的电阻变大，灯泡变亮b.电路中的电阻变大，灯泡变暗c.电路中的电阻变大，灯泡变暗d.电路中的电阻变大，灯泡变暗【答案】c【考点定位】滑动变阻器【答案】a【解析】电流表的正确使用方法是：与被测用电器串联;电流必须从电流表的正极流入，负极流出;所测量的电流不能超过电流表的量程;绝对不允许不经过用电器把电流表直接接在电源两极上;电压表的正确使用方法是：把它并联在用电器两端;必须让电流从正接线柱流入，从负接线柱流出(正接线柱与正极相连，负接线柱与负极相连);被测电压不能超过电压表所选的量程，否则会烧坏电压表. a、此图中是电流表，即串联在电路中，且正负接线柱是正确的，故a正确;b、此图中是电流表，相当于导线，所以此时将电流表并联，会发生短路，故b错误;c、此图中是电压表，应该并联在用电器两端，故c错误;d、此图中的电压表虽然并联在用电器两端，但正负接线柱接反了，故d错误;故选a.【考点定位】电流表的采用;电压表的采用a.电流表接电源b.电压表接电源c.导线接电源d.家用电器接电源【答案】b【考点定位】电路的连接a.l1、l2两端实际电压相同b.l1、l2电阻之比是25:38c.l1、l2的电流之比为25 :38d.通过调节电源电压，能使l1、l2同时正常工作【答案】b【解析】【考点定位】并联电路的特点a.电流表与的示数的比值将减小b.电压表的示数与电流表的示数的比值将增大c.电压表的示数与电流表示数的乘积将增大d.电流表与的示数的比值将减小【答案】a【解析】由电路图知道r1与r2并联，a测量干路部分的电流，当滑动变阻器的滑片p向右移动时，r1接入电路的电阻增加，电路总电阻增加，所以a与a2的示数减小，v与a1的示数不变。

2002湖北高考物理真题

2002湖北高考物理真题一、选择题1. 微观粒子 A、B与一个质子混合形成原子核C，请问哪一个是α粒子?A、A是α粒子。

B、B是α粒子。

C、C是α粒子。

D、以上都不是。

2. 关于弹性碰撞，下列说法中正确的是：A、动能守恒，动量守恒。

B、动能守恒，动量不守恒。

C、动能不守恒，动量守恒。

D、以上说法都不正确。

3. 下列物质中，哪一种物质可以用玻色-爱因斯坦凝聚温度概念解释：A、气体B、液体C、固体D、等离子体4. 在某一地点的某一垂直平面上，有一个均匀带电的二维圆环，圆环半径为 R=1.0m，环外一点 P离圆心距离为 r=2.0m，其电位差为 10V，请问该点的电场强度大小是多少？A、 20V/mB、 10V/mC、 30V/mD、 40V/m5. 下列三个长度的物理量相乘结果最可能是A、 2.5mB、 7.2m^2C、 3.4cmD、 8.6 ft6. 下列哪一种波拥有相对论效应：A、声波B、水波C、光波D、电磁波7. 一辆汽车初速度为0，匀速直线行驶20m/s，行驶40秒后，求汽车行驶的距离为多少？A、 800mB、 10mC、 60mD、 40m8. 假设一维理想气体，经历了一个等温过程，压强由 P1=1 atm增加到 P2=2 atm，过程中气体对外界做的功为 W，那么 W 是多少？A、 P1*V1 ln(P2/P1)B、 P1*V1 ln(P1/P2)C、 P1*V2 ln(P2/P1)D、 P1*V2 ln(P1/P2)9. 三个相同电荷间的电势能比另一个系统大，说明A、三个电荷间的距离小于另一个系统B、三个电荷间的距离大于另一个系统C、三个电荷的电量大于另一个系统D、三个电荷的电量小于另一个系统10. 透镜成像的条件是A、物体点和像点在水平光轴两侧B、物像距离关系满足lens-maker's公式C、光从物体处垂直于透镜面D、透镜与物体之间的距离大于焦距11. 一个电荷－q在均匀磁场中作曲线运动，那么电荷的角加速度是A、零B、和速度垂直C、和运动方向平行D、和磁力在一个平面12. 下列哪一个不是波动产生的特征A、牛顿斯公式B、多普勒效应C、光波具有干涉现象D、电磁振荡波长定律13. 一个涵盖了整个频谱且强度均匀变化的光源称为哪种光源？A、冷光源B、热光源C、白光源D、可见光源14. 原子核中质子数为＋Z，中子数为 N，该核电荷的量和质量分别为：A、 +Ze；NnB、 +Zq；MnC、 +Ze；MnD、 +Zq；Nn15. 如果一个连续运动的物体速度在不断改变，则表示什么？A、体加速度B、质点加速度C、平均速度D、匀速运动二、解答题1. 在x轴上有两个大小相等的电荷：+q和－q，他们之间的距离为2a，求电势差随位置的变化情况。

ap物理c答案

ap物理c答案【篇一：ap物理c】ass=txt>牛顿力学、占整个physics c力学考试的100%其中：a.kinematics ：运动学占18%包括：矢量（ vectors）的概念：既有大小，又有方向；矢量代数（ vector algebra）：矢量和的三角形法则是必须熟练掌握的，最简单的记忆方法就是花萌萌面对两段直的折线路径（对应两段位移矢量之和），她会选择直接连接出发点和终点的直线捷径（等效的对应两个位移矢量和），这样构成了一个矢量和三角形。

矢量的加减，点乘和叉乘，是矢量分析的基础，是我们学习ap物理c的基本数学框架一定要熟练掌握。

矢量在直角坐标系中的分量（components of vectors,coordinate systems）,特别强调的是物理上只会用“右手系”，也就是从x轴到y轴的右手螺旋拇指指向z轴，这个和叉乘的定义是一样的，好记！有了ta，大家在学电磁学的时候就不用左右手的拧麻花了。

ap 物理c还需要掌握柱坐标和球坐标，这在需要柱对称和球对称的积分问题时，就很有用了。

运动学中要用到的三大矢量：位移、速度和加速度（displacement, velocity and acceleration)，特别要注意别把距离（或者叫路程distance），速率（speed）和前面的概念搞混了，后两个概念是标量，只有在一些特殊情况下才和对应矢量的模（大小）相等。

一维运动（motion in one dimension）：一维运动的矢量性就记住有正负的方向就行，对于一维匀加速直线运动，务必掌握其最重要的三个方程：第一求速度的公式，角标i（initial）和f（final）总是代表初和末，这个公式只要从匀加速度等于平均加速度的定义就可以得到：第二个求位移的公式：，这个公式可以理解为保持初速度的匀速运动位移和初速为零的匀加速运动位移之和（第二项在v-t图中是一个三角形面积，底为⊿t，高为a*⊿t）第三个公式是把前面两个公式消去变量⊿t，得：更方便的记忆方法是公式左边用牛顿第二定律f=ma，变成外力做功的形式：f⊿x, 左边多出来的2/m转到右边，右边就正好得到物体动能的变化。

【AP物理C】【真题】解答题2008力学

AP® Physi‎c s C: Mecha‎n ics2008 Free-Respo‎n se Quest‎i onsThe Colle‎g e Board‎: Conne‎c ting‎Stude‎n ts to Colle‎g e Succe‎s sThe Colle‎g e Board‎is a not-for-profi‎t membe‎r ship‎assoc‎i atio‎n whose‎missi‎o n is to conne‎c t stude‎n ts to colle‎g e succe‎s s andoppor‎t unit‎y. Found‎e d in 1900, the assoc‎i atio‎n is compo‎s ed of more than 5,000 schoo‎l s, colle‎g es, unive‎r siti‎e s, and other‎educa‎t iona‎l organ‎i zati‎o ns. Each year, the Colle‎g e Board‎serve‎s seven‎milli‎o n stude‎n ts and their‎paren‎t s, 23,000 high schoo‎l s, and 3,500 colle‎g es throu‎g h major‎progr‎a ms and servi‎c es in colle‎g e admis‎s ions‎, guida‎n ce, asses‎s ment‎, finan‎c ial aid, enrol‎l ment‎, and teach‎i ng andlearn‎i ng. Among‎its best-known‎progr‎a ms are the SAT®, the PSAT/NMSQT‎®, and the Advan‎c ed Place‎m ent Progr‎a m® (AP®). The Colle‎g e Board‎is commi‎t ted to the princ‎i ples‎of excel‎l ence‎and equit‎y, and that commi‎t ment‎is embod‎i ed in all of its progr‎a ms, servi‎c es, activ‎i ties‎, and conce‎r ns.© 2008 The Colle‎g e Board‎. All right‎s reser‎v ed. Colle‎g e Board‎, Advan‎c ed Place‎m ent Progr‎a m, AP, AP Centr‎a l, SAT, and the acorn‎logo are regis‎t ered‎trade‎m arks‎of the Colle‎g e Board‎. PSAT/NMSQT‎is a regis‎t ered‎trade‎m ark of the Colle‎g e Board‎and Natio‎n al Merit‎Schol‎a rshi‎p Corpo‎r atio‎n.Permi‎s sion‎to use copyr‎i ghte‎d Colle‎g e Board‎mater‎i als may be reque‎s ted onlin‎e at:www.colle‎g eboa‎r /inqui‎r y/cbper‎m it.html.Visit‎the Colle‎g e Board‎on the Web: www.colle‎g eboa‎r .AP Centr‎a l is the offic‎i al onlin‎e home for the AP Progr‎a m: apcen‎t ral.colle‎g eboa‎r .PHYSI ‎C S C: MECHA ‎N ICSSECTI ‎O N IITime -45 minut ‎e s3 Quest ‎i onsDirec ‎t ions ‎: Answe ‎r all three ‎ quest ‎i ons. The sugge ‎s ted time is about ‎ 15 minut ‎e s for answe ‎r ing each of the quest ‎i ons, which ‎ are worth ‎ 15 point ‎s each. The parts ‎ withi ‎n a quest ‎i on may not have equal ‎ weigh ‎t . Show all your work in the pink bookl ‎e t in the space ‎s provi ‎d ed after ‎ each part , NOT in this green ‎ inser ‎t.2008M ‎1. A skier ‎ of mass M is skiin ‎g down a frict ‎i onle ‎s s hill that makes ‎ an angle ‎ θ with the horiz ‎o ntal ‎, as shown ‎ in the diagr ‎a m. The skier ‎ start ‎s from rest at time t = 0 and is subje ‎c t to a veloc ‎i ty-depen ‎d ent drag force ‎ du e to air resis ‎t ance ‎ of the form F = –bv, where ‎ v is the veloc ‎i ty of the skier ‎ and b is a posit ‎i ve const ‎a nt. Expre ‎s s all algeb ‎r aic answe ‎r s in terms ‎ of M, b, θ, and funda ‎m enta ‎l const ‎a nts.(a) On the dot below ‎ that repre ‎s ents ‎ the skier ‎, draw a free -body diagr ‎a m indic ‎a ting ‎ and label ‎i ng all of the force ‎s that act on the skier ‎ while ‎ the skier ‎ desce ‎n ds the hill.(b) Write ‎ a diffe ‎r enti ‎a l equat ‎i on that can be used to solve ‎ for the veloc ‎i ty of the skier ‎ as a funct ‎i on oftime.(c) Deter ‎m ine an expre ‎s sion ‎ for the termi ‎n al veloc ‎i ty v T of the skier ‎.(d) Solve ‎ the diffe ‎r enti ‎a l equat ‎i on in part (b) to deter ‎m ine the veloc ‎i ty of the skier ‎ as a funct ‎i on of time, showi ‎n g all your steps ‎.(e) On the axes below ‎, sketc ‎h a graph ‎ of the accel ‎e rati ‎o n a of the skier ‎ as a funct ‎i on of time t, and indic ‎a te the initi ‎a l value ‎ of a. Take downh ‎i ll as posit ‎i ve.taO2008M‎2. The horiz‎o ntal‎unifo‎r m rod shown‎above‎has lengt‎h 0.60 m and mass 2.0 kg. The left end of the rod is attac‎h ed to a verti‎c al suppo‎r t by a frict‎i onle‎s s hinge‎that allow‎s the rod to swing‎up or down. The right‎end of th e rod is suppo‎r ted by a cord that makes‎an angle‎of 30° with the rod. A sprin‎g scale‎of negli‎g ible‎mass measu‎r es the tensi‎o n in the cord. A 0.50 kg block‎is also attac‎h ed to the right‎end of the rod.(a) On the diagr‎a m below‎, draw and label‎vecto‎r s to repre‎s ent all the force‎s actin‎g on the rod. Show each force‎vecto‎r origi‎n atin‎g at its point‎of appli‎c atio‎n.(b)Calcu‎l ate the readi‎n g on the sprin‎g scale‎.The rotat‎i onal‎inert‎i a of a rod about‎its cente‎r is 1ML2, where‎M is the mass of the rod and L is its lengt‎h.12Calcu‎l ate the rotat‎i onal‎inert‎i a of the rod-block‎syste‎m about‎the hinge‎.(d)If the cord that suppo‎r ts the rod is cut near the end of the rod, calcu‎l ate the initi‎a l angul‎a r accel‎e rati‎o n of th erod-block‎syste‎m about‎the hinge‎.2008M‎3. In an exper‎i ment‎to deter‎m ine the sprin‎g const‎a n t of an elast‎i c cord of lengt‎h 0.60 m, a stude‎n t hangs‎the cord from a rod as repre‎s ente‎d above‎and then attac‎h es a varie‎t y of weigh‎t s to the cord. For each weigh‎t, the stude‎n t allow‎s the weigh‎t to hang in equil‎i briu‎m and then measu‎r es the entir‎e lengt‎h of the cord. The data are recor‎d ed in the table‎below‎:(a)Use the data to plot a graph‎of weigh‎t versu‎s lengt‎h on the axes below‎. Sketc‎h a best-fit strai‎g ht line throu‎g hthe data.(b) Use the best-fit line you sketc‎h ed in part (a) to deter‎m ine an exper‎i ment‎a l value‎for the sprin‎g const‎a nt k ofthe cord.The stude‎n t now attac‎h es an objec‎t of unkno‎w n mass m to the cord and holds‎the objec‎t adjac‎e nt to the point‎at which‎the top of the cord is tied to the rod, as repre‎s ente‎d above‎. When the objec‎t is relea‎s ed from rest, it falls‎1.5 m befor‎e stopp‎i ng and turni‎n g aroun‎d. Assum‎e that air resis‎t ance‎is negli‎g ible‎.(c)Calcu‎l ate the value‎of the unkno‎w n mass m of the objec‎t.(d)i. Calcu‎l ate how far down the objec‎t has falle‎n at the momen‎t it attai‎n s its maxim‎u m speed‎.ii.Expla‎i n why this is the point‎at which‎the objec‎t has its maxim‎u m speed‎.iii.Calcu‎l ate the maxim‎u m speed‎of the objec‎t.。

ap物理c】真题】解答题c2000

【AP物理C】【真题】解答题C2000AP? Physics C2000 Free response QuestionsThe mat erials included in these files are intended for use by AP teachers for course and exam preparation in the classroom; permission for any other use must be sought from the Advanced Placement Program?. Teachers may reproduce them, in whole or in part, in limited quantities, for face-to-face teaching purposes but may not mass distribute the materials, electronically or ot herwise. These mat erials and any copies made of t hem may not be resold, and the copyright notices must be retained as they appear here. This permission does not apply to any third-party copyrights contained herein.These materials were produced by Educational Testing Service? (ETS?), which develops and administers the examinations of the Advanced Placement Program for the College Board. The College Board and Educational Testing Service (ETS) are dedicated to the principle of equal opportunity, and their programs, services, and employment policies are guided by that principle.The College Board is a national nonprofit membershipassociation dedicated to preparing, inspiring, and connecting students to college and opportunity. Founded in 1900, the association iscomposed of more than 4,200 schools, colleges, universities, and other educational organizations. Each year, the College Board serves over three million students and their parents, 22,000 high schools, and 3, 500 colleges, through major programs and services in college admission, guidance, assessment, financial aid, enrollment, and teaching and learning・ Among its best-known programs are the SAT?, the PSAT/NMSQT?, and the Advanced Placement Program? (AP?). The College Board is committed to the principles of equity andexcellence, and that comm it men t is embodied in allof its programs, services, activities, and concerns.API EL is a trademark owned by the College Ent rance Examination Board・ PSAT/NMSQT is a registeted trademark jointly owned by the College Entrance Examination Board and the National Merit Scholarship Corporation. Educational Testing Service and ETS are registered trademarks of Educational Testing Service.Copyright ? 2000 by College Entrance Examination Board.All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.(2000 Ml) You are conducting an experiment to measure the acceleration due to gravity gu at an unknown location. In the measurement apparatus, a simple pendulum swings past a photogate located at the pendulum^ s lowest point, which records the time tlO for the pendulum to undergo 10 full oscillations. The pendulum consists of a sphere of mass m at the end of a st ring and has a leng th 1. There are four versions of this apparatus, each with a different length. All four are at the unknown location, and the data shown below are sent to you during the experiment.tio T T2 ? (s) (s) (s2) (cm) 12 18 21 32 a. For each pendulum, calculate the period T and the square of the period. Use a reasonable number of signifies nt figures. Enter these results in the table above.b.On the axes below, plot the square of the period versus the length of the pendulum. Draw a best-fit straight linefor this data. c. Assuming that each pendulum undergoessmall amplitude oscillations, from your fit determine the experimental value gexp of the acceleration due to gravity at this unknown location. Justify your answer.d.If the measurement apparatus allows a determination of gexp that is accurate to within 4%, is your experimentalvalue in agreement with the value m/s2 ? Justify your answer.e.Someone informs you that the experimental appara tus is in fac t neat Ear th's surface, but that the experiment hasbeen conducted inside an elevator with a constant acceleration a. Assuming that your experimental value g is exact, determine the magnitude and direction of the elevatoH s acceleration.Copyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registeted trademarks of the College Entrance Examination Board.2000M2. A rubber ball of mass m is dropped from a cliff. As the ball falls, it is subject to air drag (a resistiveforce caused by the air). The drag force on the ball has magnitude bv2, where b is a constant drag coefficient and v is the instantaneous speed of the ball. The drag coeff icie nt b is direc tly proportional to the cross-sectional area of the ball and the density of the air and does not depend on the mass of the ball. As the ball falls, its speed approaches a constant value called the terminal speed.a.On the figure below, draw and label all the forces on the ball at some instant before it reaches terminal speed.b.State whether the magnitude of the acceleration of the ball of mass m increases, decreases, or remains the sameas the ball approaches terminal speed. Explain.c.Write, but do NOT solve, a differential equation for the instantaneous speed v of the ball in terms of time t, thegiven quantities, and fundamentai constants.d.Det ermine the terminal speed vt in t erms of the given quantities and fundamental constants.e.Determine the energy dissipated by the drag force during the fall if the ball is released at height h and reachesits terminal speed before hitting the ground, in terms of the given quantities and fundamental constants.2000M3・ A pulley of radius R1 and rotational inertiaII is mounted on an axle with negligible friction. A light cord passing over the pulley has two blocks of mass m attached to either end, as shown above. Assume that the cord does not slip on the pulley. Det ermine the answers to parts (a) and (b) in t erms of m, Rl, II, and fundamental constants, a. Determine the tension T in the cord.b.One block is now removed from the right and hung on the left・ When the system is released from rest, the threeblocks on the left accelerate downward with an accelera tion g/3 • Det ermine the following, i. The tension T3 in the section of cord supporting the three blocks on the left ii. The tension T1 in the section of cord supporting the single block on the right iii. The rotational inertia II of the pulleyCopyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the CollegeEntrance Examination Board.c.The blocks are now removed and the cord is tied into a loop, which is passed around the original pulley and asecond pulley of radius 2R1 and rotational inertia 1611. The axis of the original pulley is attached to a motor that rotates it at angular speed ?1, which in turn causes the larger pulley to rotate. The loop does not slip on the pulleys. Det ermine the following in terms of II, RI, and ?1. i. The angular speed ?2 of the larger pulleyii. The angular momentum L2 of the larger pulley iii. The totai kinetic energy of the system2000E1. Lightbulbs A, B, and C are connected in the circuit shown above.a.List the bulbs in order of t heir brigh tn ess, from brightest to least bright・ If any bulbs have the same brightness,state which ones. Justify your answer.Now a switch S and a mH indue tor are added to the circuit; as shown above. The switch is closed at time t二0・b.Det ermine the curre nts IA, IB, and IC for the following times. i. Immediately after the switch is closedii. A long time after the switch is closedCopyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.c.On the axes below, sketch the magnitude of the potential difference VL across the inductor as a function of time,from immediately after the switch is closed untila long time after the switch is closed.d.Now consider a similar circuit with an uncharged ?F capacitor instead of the induetor, as shown above. Theswitch is again closed at time t 二0・ On the axes below, sketch the magnitude of the potential difference Vcap across the capacitor as a function of time, from immediately after the switch is closed until a long time after the switch is closed.Copyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.2000E2・Three particles, A, B, and C, have equal positive charges Q and are held in place at the vertices of anequilater&l triangle with sides of length 1, as shown in the figures below. The dot ted lines represe nt the bisec tors for each side. The base of the t riangle lies on the x-axis, and the altitude of the triangle lies on the y-axis.a.i.Point Pl, the intersection of the three bisec to rs, loca tes the geometric center of the triangle and is one pointwhere the electrie field is zero. On Figure 1 above, draw the elec trie field vec tors EA, EB, and EC at P, due to each of the three charges. Be sure your arrows are drawn to reflect the relative magnitude of the fields・ii.Another poi nt where the elec trie field is zero ispoint P2 at (0, y2). On Figure 2 above, draw electrie field vectors EA, EB, and EC at P2 due to each of the three point charges. Indicate below whether the magnitude of each of these vectors is greater than, less than, or the same as for point Pl.EA EB EC Greater than at Pl Less than at Pl The same as at Pl b. Explain why the x-component of the total electric field is zero at any point on the y-axis.c.Write a general expression for the electrie potential V at any point on the y-axis inside the trianglein terms of Q,1, and y.d.Describe how the answer to part (c) could be used to determine the y-coordinates of points Pl and P2 at whichthe electric field is zero. (You do not need toactually determine these coordinates.)Copyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.2000E3. A capacitor consists of two conducting, coaxial, cylindrical shells of radius a and b, respec ti vely, and leng th L » b. The space bet ween the cylinders is filled with oil that has a dielectric constant K .Initially bothcylinders are uncharged, but then a battery is used to charge the capacitor, leaving a charge +Q on the inner cylinder and -Q on the outer cylinder, as shown above. Let r be the radial distance from the axis of the capacitor.ing Gauss，s 1aw, determine the electrie field midway along the length of the cylinder for the following valuesof r, in t erms of the given qua ntities and fundamental constants. Assume end effects are negligible. i.a b. Determine the following in terms of the givenquantities and fundamentai constants.i. The potential difference across the capacitor ii. The capacitance of this capacitorc.Now the capacitot is discharged and the oil is drained from it. As shown above, a battery of emf ? is connectedto opposite ends of the inner cylinder and a battery of emf 3? is connected to opposite ends of the outer cylinder. Each cylinder has resistance R. Assume that end effects and the contributions to the magnetic field from the wires are negligible. Using Ampere" s law, determine the magnitude Bof the magnetic field midway along the length of the cylinders due to the current in the cylinders for the following values of r. i. a Copyrigh t ? 2000 by College Ent rance Examina tion Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.AP? Physics C2000 Free response QuestionsThe mat erials included in these files are intended for use by AP teachers for course and exam preparation in the classroom; permission for any other use must be sought from the Advanced Placement Program?. Teachers may reproduce them, in whole or in part, in limited quantities, for face-to-face teaching purposes but may not mass distribute the materials,electronically or otherwise. These mat erials and any copies made of t hem may not be resold, and the copyright notices must be retained as they appear here. This permission does not apply to any third-party copyrights contained herein.These materials were produced by Educational Testing Service? (ETS?), which develops and administers the examinations of the Advanced Placement Program for the College Board. The College Board and Education&l Testing Service (ETS) are dedicated to the principle of equal opportunity, and theirprograms, services, and employment policies are guided by that principle.The College Board is a national nonprofit membership association dedicated to preparing, inspiring, and connecting students to college and opportunity. Founded in 1900, the association iscomposed of more than 4,200 schools, colleges, universities, and other educational organizations. Each year, the College Board serves over three million students and their parents，22,000 high schools, and 3, 500 colleges, through major programs and services in college admission, guidance, assessment, financial aid, enrollment, and teaching andlearning・ Among its best-known programs are the SAT?, the PSAT/NMSQT?, and the Advanced Placement Program? (AP?). The College Board is committed to the principles of equity andexcellence, and that commitment is embodied in all of its programs, services, activities, and concerns.API EL is a trademark owned by the College Ent rance Examination Board・PSAT/NMSQT is a registeted trademark jointly owned by the College Entrance Examination Board and the National Merit Scholarship Corporation. Educational Testing Service and ETS are registered trademarks of Educational Testing Service.Copyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.(2000 Ml) You are conducting an experiment to measure the acceleration due to gravity gu at an unknown location. In the measurement apparatus, a simple pendulum swings past a photogate located at the pendulum^ s lowest point, which records the time tlO for the pendulum to undergo 10 fulloscillations. The pendulum consists of a sphere of mass m at the end of a st ring and has a length 1. There are four versions of this apparatus, each with a different length. All four are at the unknown location, and the data shown below are sent to you during the experiment.tio T T2 ? (s) (s) (s2) (cm) 12 18 21 32 a. For each pendulum, calculate the period T and the square of the period. Use a reasonable number of significant figures. Enter these results in the table above.b.On the axes below, plot the square of the period versus the length of the pendulum. Draw a best-fit straight linefor this data. c. Assuming that each pendulum undergoes small amplitude oscillations, from your fit determine the experimentai value gexp of the acceleration due to gravity at this unknown location. Justify your answer.d.If the measurement apparatus allows a determination of gexp that is accurate to within 4%, is your experimentalvalue in agreement with the value m/s2 ? Justify your answer.e.S omeone informs you that the experimental apparatus isin fact near Earth^ s surface, but that the experiment has been conducted inside an elevator with a constant acceleration a. Assuming that your experimentai value g is exact, determine the magnitude and direction of the elevatoH s acceleration.Copyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.2000M2. A rubber ball of mass m is dropped from a cliff. As the ball falls, it is subject to air drag (a resistive force caused by the air). The drag force on the ball has magnitude bv2, where b is a const&nt drag coefficient and v is the instantaneous speed of the ball. The drag coefficient b is directly proportional to the cross-sectional area of the ball and the density of the air and does not depend on the mass of the ball. As the ball falls, its speed approaches a constant value called the terminal speed.a.On the figure below, draw and label all the forces on the ball at some inst&nt before it reaches terminal speed.b.State whether the magnitude of theacceleration of the ball of mass m increases, decreases, or remains the sameas the ball approaches terminal speed. Explain.c.Write, but do NOT solve, a differential equation for the instantaneous speed v of the ball in terms of time t, thegiven quantities, and fundamentai constants.d・Determine the terminal speed vt in terms ofthe given quantities and fundamental constants.e. Determine the energy dissipated by the drag force during the fall if the ball is released at height h and reachesits terminal speed before hitting the ground, in terms of the given quantities and fundamental constants.2000M3・ A pulley of radius R1 and rotational inertiaII is mounted on an axle with negligible friction. A light cord passing over the pulley has two blocks of mass m attached to either end, as shown above. Assume that the cord does not slip on the pulley.Determine the answers to parts (a) and (b) in terms of m, Rl, II, and fundamental constants. a. Determine the tension T in the cord.b.One block is now removed from the right and hung on the left・ When the system is released from rest, the threeblocks on the left accelerate downward with an accelera tion g/3 • Det ermine the followin g, i. The tension T3 in the section of cord supporting the three blocks on the left ii. The tension T1 in the section of cord supporting the single block on the right iii. The rotation&l inertia II of the pulleyCopyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.c.The blocks are now removed and the cord is tied into a loop, which is passed around the original pulley and asecond pulley of radius 2R1 and rotational inertia 1611. The axis of the original pulley is attached to a motor that rotates it at angular speed ?1, which in turn causes the larger pulley to rotate. The loop does not slip on the pulleys.Det ermine the following in terms of II, RI, and ?1. i. The angular speed ?2 of the larger pulleyii. The angular momentum L2 of the larger pulley iii. The total kinetic energy of the system2000E1. Lightbulbs A, B, and C are connected in the circuit shown above.a.List the bulbs in order of t heir brigh tn ess, from brightest to least bright. If any bulbs have the same brightness,state which ones. Justify your answer.Now a switch S and a mH indue tor are added to the circuit; as shown above. The switch is closed at time t 二0.b.Det ermine the curre nts IA, IB, and IC for the following times. i. Immediately after the switch is closed ii. A long time after the switch is closedCopyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.c.On the axes below, sketch the magnitude of thepotenti&l difference VL across the inductor as a function of time,from immediately after the switch is closed unt订a long time after the switch is closed.d.Now consider a similar circuit with an uncharged ?F capacitor instead of the inductor, as shown above. Theswitch is again closed at time t = 0. On the axes below, sketch the magnitude of the potential difference Vcap across the capacitor as a function of time, from immediately after the switch is closed until a long time after the switch is closed.Copyright ? 2000 by College Entrance Examination Board. All rights reserved.College Board, Advanced Placement Program, AP, SAT,and the acorn logo are registered trademarks of theCollege Entrance Examination Board.。

美国2002高中物理竞赛题及答案整理

ATTENTION: All Division I students, START HERE.All Division II students, skip the first ten questions, begin on question 11.THE NEXT TWO QUESTIONS REFER TO THE FOLLOWING GRAPH1. The graph represents the relationshipbetween distance and time for an object that ismoving along a straight line. What is theinstantaneous speed of the object at t = 5.0seconds?A) 0.0 m/sB) 0.8 m/sC) 2.5 m/sD) 4.0 m/sE) 6.8 m/s2. Between what times did the object have a non-zero acceleration?A) 0 s only D) 0 s to 8 sB) 0 s to 5 s E) the object was not accelerating at any timeC) 5 s to 8 s3. An airplane takes off and flies 300 miles at an angle of 30o north of east. It then changes direction and flies 600 miles due west before landing. In what direction is the plane’s landing point from its starting point?A) 14.2o north of west D) 66.2o north of westB) 23.8o north of west E) 75.9o north of westC) 37.4o north of west4. If a ball is thrown directly upwards with twice the initial speed of another, how much higher will it be at its apex?A) 8 times D) 2 timesB) 4 times E)2timesC)22 times5. The diagram shows two transverse pulses moving along a string. One pulse is moving to the right and the second is moving tothe left. Both pulses reach point x atthe same instant. What would be theresulting motion of point x as the twopulses pass each other?A) up then downB) down then upC) up, down, upD) down, up, downE) there would be no motion, the pulses cancel one another6. Three resistors of different values can be connected together in different configurations. If all three resistors are used in a circuit, how many different values of total resistance can be produced?A) 2 B) 3 C) 5 D) 6 E) 87. The diagram shows two water pulseswhich were originally produced at point A andare beginning to be reflected from a wide barrieras shown. Which of the points in the diagramwould represent a virtual source for thereflected waves?A) Point AB) Point BC) Point CD) Point DE) There would be no virtual source forthe reflected pulses.8. A gas is enclosed in a cylindrical piston. When the gas is heated from 0o C to 100o C, the piston is allowed to move to maintain a constant pressure. According to the Kinetic-Molecular Theory of MatterA) the mass of the gas will increaseB) the number of molecules of gas must increaseC) the size of the individual molecules has increasedD) the average speed of the molecules has increasedE) the molecules continue to strike the sides of the container with the same energy9. When a positive electrically charged glass rod is brought near a neutral hollow metal sphere suspended by an insulating string, the sphere will be attracted to the rod because:A) the rod is much larger than the sphereB) the rod removes electron from the sphereC) the electric charge produces a magnetic field to attract the sphereD) the charge on the rod causes a separation of charge in the sphereE) some of the protons from the rod have been given to the sphere10. In Rutherford's famous gold foil scattering experiment, he found that most alpha particles would pass through the foil undeflected. Which of the following nuclear properties can be inferred from this observation?A) The nucleus must have a positive chargeB) Most of the mass of an atom is in the nucleusC) The nucleus contains both protons and neutronsD) The diameter of the nucleus is small compared to the diameter of the atomE) None of the aboveATTENTION: All Division I students, continue to question 40.All Division II students, START HERE. Numbers 1-10 on you answer sheet should remain blank. Your first answer should be number 11.THE NEXT THREE QUESTIONS REFER TO THE FOLLOWING SCENARIO The diagram below represents a toy car starting from rest and uniformly accelerating across the floor. The time and distance traveled from the start are shown in the diagram.11. What was the average speed of the cart between 0.1 seconds and 0.3 seconds?A) 0.6 m/s D) 4.8 m/sB) 1.9 m/s E) 60 m/sC) 2.4 m/s12. What was the acceleration of the cart during the first 0.4 seconds?A) 6.0 m/s/s D) 25 m/s/sB) 9.8 m/s/s E) 50 m/s/sC) 12 m/s/s13. What was the instantaneous velocity of the cart at 96 centimeters from the start?A) 0.6 m/s D) 4.8 m/sB) 1.9 m/s E) 60 m/sC) 2.4 m/s14. An intrinsic property of matter is one that does not depend on the quantity of matter present. Which of the following properties is NOT an intrinsic property?A) Density B) Temperature C) Specific Heat D) Half-life E) Inertia15. A positively charged particle moves to the right. Itenters a region of space in which there is an electric fielddirected up the plane of the paper (see figure). In whichdirection does a magnetic field have to point in this region sothat the particle maintains a constant velocity?A) Into the plane of the pageB) Out of the plane of the pageC) To the rightD) To the leftE) Up the plane of the page16. During a particular kind of radioactive decay, a particle is emitted from the nucleus of an atom and the atom's atomic number increases by one. This decay necessarily involves the emission of ______________ from the nucleus?A) an alpha particle D) a protonB) a beta particle E) a neutronC) a gamma rayTHE NEXT TWO QUESTIONS REFER TO THE FOLLOWING SCENARIO The motion of a circus clown on a unicycle moving in a straight lineis shown in the graph at the right.17. What would be the acceleration of the clown at 5 s?A) 1.6 m/s2D) 8.0 m/s2B) 2.0 m/s2E) none of the aboveC) 3.4 m/s218. After 12 seconds, how far is the clown from her originalstarting point?A) 0 m B) 10 m C) 34 m D) 47 m E) 74 m19. As a rocket blasts away from the earth with a cargo for the international space station, which of the following graphs would best represent the gravitational force on the cargo versus distance from the surface of the Earth?20. The graph shows the relationship between themass of a number of rubber stoppers and their resultingweight on some far-off planet. The slope of the graph is arepresentation of the:A) mass of a stopperB) density of a stopperC) volume of a stopperD) acceleration due to gravityE) number of stoppers for each unit of weightAn ideal battery, an ideal ammeter,a switch and three resistors are connectedas shown. With the switch open as shownin the diagram the ammeter reads 2.0amperes.21. With the switch open, what would be the potential difference across the 15 ohm resistor?A) 30 V B) 40 V C) 60 V D) 70 V E) 110V22. With the switch open, what must be the voltage supplied by the battery?A) 30 V B) 40 V C) 60 V D) 70 V E) 110 V23. When the switch is closed, what would be the current in the circuit?A) 1.1 A B) 1.7 A C) 2.0 A D) 2.3 A E) 3.0 A24. Two small hollow metal spheres hung on insulating threads attract oneanother as shown. It is known that a positively charged rod will attract ball A.I. Ball A has a positive chargeII. Ball B has a negative chargeIII. Ball A and Ball B have opposite chargesWhich of the above can be correctly concluded about the charge on the balls?A) I only B) II only C) III only D) all of these E) none of these25. If M represents units of mass, L represents units of length, and T represents units of time, the dimensions of power would be:A)MLT2B)MLT22C)MLT23D)MLTE)MLT226. Consider two laboratory carts of different masses but identical kinetic energies and the three following statements.I. The one with the greatest mass has the greatest momentumII. The same impulse was required to accelerate each cart from restIII. Both can do the same amount of work as they come to a stopWhich of the above statements would be correct?A) I only D) I and II onlyB) II only E) I and III onlyC) III onlyThe diagram below shows three roller coaster tracks of equal length. Assume that on all tracks the roller coaster carts start from rest at the same elevation and moves frictionlessly over the tracks to the finish.27. If all roller coaster carts start at the positions shown, on which track would the roller coaster cart be traveling the fastest at the finish?A) Cart A D) All would reach the finish with the same speedB) Cart B E) More information would be requiredC) Cart C28. If all roller coaster carts start at the positions shown, on which track would the roller coaster cart reach the finish first?A) Cart A D) All would reach the finish at the same timeB) Cart B E) More information would be requiredC) Cart C29. Assume the roller coaster cart rollsfrictionlessly along the curved track from point A topoint C under the influence of gravity. What would bethe direction of the cart's acceleration at point B?A) upwardB) downwardC) forwardD) backwardE) no acceleration30. A box falls to the ground from a delivery truck traveling at 30 m/s. After hitting the road, it slides 45 meters to rest. How long does it take the box to come to rest?A) 0.67 s B) 1.5 s C) 2.0 s D) 3.0 s E) 6.0 s31. A compass is placed near a coil of wire. A conventionalelectrical current is then run through the coil from left to right asshown. This will cause the North pole of the compass to:A) point toward the leftB) point toward the rightC) point toward the bottom of the paperD) not move since the magnetic field of the coil is into thepaperE) not move since the magnetic field of the coil is out of the paper32. An automobile engine delivers 24,000 watts (about 32 hp) of power to a car's driving wheels. If the car maintains a constant speed of 30 m/s (about 65 mph), what is the magnitude of the retarding force acting on the car?A) 800 N D) 720,000 NB) 960 N E) 1,560,000 NC) 1950 N33. A short burst of white light strikes a rectangular glass block with an angle of incidence of 0o. Which color of transmitted light would be the first to emerge from the opposite side?A) red D) violetB) yellow E) all colors would emerge at the same instantC) green34. Two containers are filled with gases at the sametemperature. In the container on the left is a gas of molar mass2M, volume 2V, and number of moles 2n. In the container onthe right is a gas of molar mass M, volume V, and moles n.Which is most nearly the ratio of the pressure of the gas on theleft to the pressure of the gas on the right?A) 1:1 D) 8:1B) 2:1 E) 16:1C) 4:135. A 300 eV electron is aimed midway between twoparallel metal plates with a potential difference of 400 V. Theelectron is deflected upwards and strikes the upper plate asshown. What would be the kinetic energy of the electron justbefore striking the metal plate?A) 360 eV B) 400 eV C) 500 eV D) 700 eV E) 740 eV36. Two masses, m 1 and m 2, are connected by a cord and arrangedas shown in the diagram with m 1 sliding along on a frictionless surfaceand m 2 hanging from a light frictionless pulley. What would be themass of the falling mass, m 2, if both the sliding mass, m 1, and thetension, T , in the cord were known?A) 11()g − D) m g T g1− B) 12Tg E) ()()T gm g T m −−11) C) Tm gm T 11()−37. A diffraction grating of 1000 lines/cm has red light of wavelength 700nm pass through it. The distance between the first and third principal bright spots on a screen 2.0m away isA) 14 cm B) 28 cm C) 42 cm D) 140 cm E) 280 cm38. A 5 x 10-6 coulomb electric charge is placed midway between two parallel metal plates connected to a 9-volt battery. If the electric charge experiences a force of 1.5 x 10-4 newtons, what is the separation of the metal plates?A) 6.75 x 10-9m B) 2.7 x 10-4m C) 3.7 x 10-3m D) 0.30 m E) 3.3 m39. A parallel-plate capacitor is connected to a resistanceless circuit with a battery having emf î until the capacitor is fully charged. The battery is then disconnected from the circuit and the plates of the capacitor are moved to half of their original separation using insulated gloves. Let V new be the potential difference across the capacitor plates when the plates are moved together. Let V old be the potential difference across the capacitor plates when connected to the battery. V V new old= A) 41 B) 21 C) 1 D) 2 E) 440. A box with a mass of 50 kg is dragged across thefloor by a rope which makes an angle of 30o with thehorizontal. Which of the following would be closest to thecoefficient of kinetic friction between the box and the floor ifa 250 newton force on the rope is required to move the crateat a constant speed of 20 m/s as shown in the diagram?A) 0.26 B) 0.33 C) 0.44 D) 0.59 E) 0.77ATTENTION: All Division I students, STOP. All Division II students, turn page and continue to question 50.41. A person throws a small object from the top of a building at an angle of 300 above the horizontal. At the instant that the object returns to the same height from which it was thrown, at what rate is the speed of the object changing? Ignore air resistance and let g be the acceleration due to gravity.A) 0 B) g tan 30o C) g sin 30o D) g cos 30o E) g42. A small box of mass m is placed on top of a larger box of mass2m as shown in the diagram at right. When a force F is applied to thelarge box, both boxes accelerate to the right with the same acceleration.If the coefficient of friction between all surfaces is ì, what would be theforce accelerating the smaller mass?A) µmg F −3 B) µmg F 3− C) µmg F − D) 3µmg F − E) 3F43. A light ray is incident normal to a thin layer ofglass. Given the figure, what is the minimum thicknessof the glass that gives the reflected light an orangish color( ëair = 600 nm) ?A) 50 nm D) 200 nmB) 100 nm E) 500 nmC) 150 nm44. A thermally insulating container has a membrane separating the container into two equal parts. In one part is a vacuum. In the other part is an ideal gas of temperature T and internal energy U. The membrane is punctured and the gas rushes into the region which was vacuum. After the system has returned to equilibrium, which of the following is NOT true for the gas?A) The temperature of the gas is unchanged.B) No work is done by the gas on the surroundings.C) There is no heat exchanged by the gas with the surroundings.D) There is no entropy change of the system.E) The internal energy of the gas is unchanged.45. A light inextensible string is connected to a mass, M , that provides the tension in the string. A length L of the string has a fundamental frequency of vibration of f M . If a second identical mass is now connected to the original mass, the newfundamental frequency of the string (f 2M ) of string length L incomparison to the fundamental frequency with only one massconnected f M isA) f f M M 22= D) f f M M 212= B) f f M M 22= E) f f M M 212= C) f f M M 2=46. A hotplate is designed such that it has a resistance of 12 Ù when operating at 120 volts. What is the minimum amount of time that it would take to warm 0.45 kg of water from 15o C to 85o C?A) 20 s B) 26 s C) 110 s D) 180 s E) 220 s47. A car heads toward a brick wall in a crash test at 30 m/s. The horn is emitting a sound with frequency 250 Hz as it approaches the wall. If the air is still and the speed of sound in air is 340 m/s, what beat frequency from the horn would the driver of the car detect?A) 0 Hz B) 22 Hz C) 24 Hz D) 41 Hz E) 48 Hz48. An object of mass M is dropped from a height H above the ground. The object crashes into some soft earth and comes to rest by compressing the earth a distance of H /2. Assuming that air resistance is negligible, what is the magnitude of the average constant force exerted by the ground on the object while coming to rest?A) 0 B) 32 Mg C) Mg D) 2Mg E) 3Mg49. A solid, uncharged conducting sphere of radius 3a contains a hollowed spherical region of radius a . A point charge +Q is placed at the common center of the spheres. Taking V = 0 as r →∞, the potential at position r =2a from the center of the spheres is:A) 0 D) 23kQ aB) kQ a 3 E) kQ aC) kQ a24050. Two thin lenses each with afocal length of +10 cm are located30 cm apart with their optical axesaligned as shown. An object isplaced 35 cm from the first lens.After the light has passed throughboth lenses, at what distance fromthe second lens will the final image be formed?A) 65 cm B) 35 cm C) 27 cm D) 17 cm E) -14 cmATTENTION: All Division II students STOP. All Division II answers should appear inNumbers 11-50 on your answer sheet. Numbers 1-10 on you answer sheet should remain blank.2002 PhysicsBowl Answer SheetQuestion Answer Question Answer1 B 26 E2 C 27 B3 B 28 A4 B 29 A5 C 30 D6 E 31 A7 C 32 A8 D 33 A9 D 34 A10 D 35 C11 C 36 C12 C 37 B13 D 38 D14 E 39 B15 B 40 D16 B 41 C17 B 42 A18 E 43 B19 E 44 D20 D 45 B21 A 46 C22 D 47 E23 D 48 E24 E 49 B25 C 50 Cpage 12。

ap物理c力学知识点

ap物理c力学知识点【篇一：ap物理c力学知识点】环球教育频道小编为大家整理了“力学的知识点解析”，下面是详细内容，供大家参考学习。

【ctrld收藏，下次查看更方便】ap 物理c 力学newtonian mechanics牛顿力学、占整个physicsc力学考试的100%其中：a. kinematics ：运动学占18%。

包括：矢量( vectors)的概念：既有大小，又有方向;矢量代数( vectoralgebra)：矢量和的三角形法则是必须熟练掌握的，最简单的记忆方法就是花萌萌面对两段直的折线路径(对应两段位移矢量之和)，她会选择直接连接出发点和终点的直线捷径(等效的对应两个位移矢量和)，这样构成了一个矢量和三角形。

矢量的加减，点乘和叉乘，是矢量分析的基础，是我们学习ap物理c的基本数学框架一定要熟练掌握。

矢量在直角坐标系中的分量(components of vectors, coordinatesystems),特别强调的是物理上只会用“右手系”，也就是从x轴到y轴的右手螺旋拇指指向z轴，这个和叉乘的定义是一样的，好记!有了ta，大家在学电磁学的时候就不用左右手的拧麻花了。

ap物理c还需要掌握柱坐标和球坐标，这在需要柱对称和球对称的积分问题时，就很有用了。

运动学中要用到的三大矢量：位移、速度和加速度(displacement,velocity andacceleration)，特别要注意别把距离(或者叫路程distance)，速率(speed)和前面的概念搞混了，后两个概念是标量，只有在一些特殊情况下才和对应矢量的模(大小)相等。

一维运动(motion in onedimension)：一维运动的矢量性就记住有正负的方向就行，对于一维匀加速直线运动，务必掌握其最重要的三个方程：第一求速度的公式，角标i(initial)和f(final)总是代表初和末，这个公式只要从匀加速度等于平均加速度的定义就可以得到：第二个求位移的公式：，这个公式可以理解为保持初速度的匀速运动位移和初速为零的匀加速运动位移之和(第二项在v-t图中是一个三角形面积，底为 t，高为a* t)第三个公式是把前面两个公式消去变量 t，得：更方便的记忆方法是公式左边用牛顿第二定律f=ma，变成外力做功的形式：f x,左边多出来的2/m转到右边，右边就正好得到物体动能的变化。

2002年普通高等学校招生全国统一考试物理试卷及答案全国卷

2002年普通高等学校招生全国统一考试<全国卷）物理部分第I卷<选择题）在下列各题地四个选项中，只有一个选项是符合题目要求地.15．目前普遍认为，质子和中子都是由被称为u夸克和d夸克地两类夸克组成.u夸克带电量为e，d夸克带电量e，e为基元电荷.下列论断可能正确地是A 质子由1个u夸克和1个d夸克组成，中子由1个u夸克和2个d夸克组成B 质子由2个u夸克和1个d夸克组成，中子由1个u夸克和2个d夸克组成C 质子由1个u夸克和2个d夸克组成，中子由2个u夸克和1个d夸克组成D 质子由2个u夸克和1个d夸克组成，中子由1个u夸克和1个d夸克组成16、在光滑水平地面上有两个相同地弹性小球A、B，质量都为m.现B球静止，A球向B球运动，发生正碰.已知碰撞过程中总机械能守恒，两球压缩最紧时地弹性势能为E P，则碰前A球地速度等于A B C 2 D 217．图中EF、GH为平行地金属导轨，其电阻可不计，R为电阻器，C为电容器，AB为可在EF和CH上滑动地导体横杆.有均匀磁场垂直于导轨平面.若用I1和I2分别表示图中该处导线中地电流，则当横杆ABA 匀速滑动时，I1＝0，I2＝0B 匀速滑动时，I1≠0，I2≠0C 加速滑动时，I1＝0，I2＝0D 加速滑动时，I1≠0，I2≠018．质点所受地力F随时间变化地规律如图所示，力地方向始终在一直线上.已知t＝0时质点地速度为零.在图示t1、t2、t3和t4各时刻中，哪一时刻质点地动能最大？A t1B t2C t3D t419．为了观察门外情况，有人在门上开一小圆孔，将一块圆柱形玻璃嵌入其中，圆柱体轴线与门面垂直.从圆柱底面中心看出去，可以看到地门外入射光线与轴线间地最大夹角称做视场角.已知该玻璃地折射率为n，圆柱长为l，底面半径为r，则现场角是A arcsinB arcsinC arcsinD arcsin20．在如图所示地电路中，R1、R2、R3和R4皆为定值电阻，R5为可变电阻，电源地电动势为ε，内阻为r.设电流表A地读数为I，电压表V地读数为U.当R5地滑动触点向图中a瑞移动时，A I变大，U变小B I变大，U变大C I变小，U变大D I变小，U变小第Ⅱ卷<非选择题）26．<20分）蹦床是运动员在一张绷紧地弹性网上蹦跳、翻滚并做各种空中动作地运动项目.一个质量为60kg地运动员，从离水平网面3.2m高处自由下落，着网后沿竖直方向蹦回到离水平网面5.0m高处.已知运动员与网接触地时间为1.2s.若把在这段时间内网对运动员地作用力当作恒力处理，求此力地大小.<g＝10m/s2）27．<20分）电视机地显像管中，电子束地偏转是用磁偏转技术实现地.电子束经过电压为U地加速电场后，进入一圆形匀强磁场区，如图所示.磁场方向垂直于圆面.磁场区地中心为O，半径为r.当不加磁场时，电子束将通过O点而打到屏幕地中心M点.为了让电子束射到屏幕边缘P，需要加磁场，使电子束偏转一已知角度θ，此时磁场地磁感应强度B应为多少？29．<37分）大气压强对许多物理实验和化学实验有着重要影响.Ⅰ．<17分）现用“验证玻意耳定律”地仪器来测量大气压强p0.注射器针筒已被固定在竖直方向上，针筒上所标刻度是注射器地容积，最大刻度V m＝10ml.注射器活塞已装上钩码框架，如图所示.此外，还有一架托盘天平、若干钩码、一把M尺、一个针孔橡皮帽和少许润滑油.<1）下面是实验步骤，试填写所缺地②和⑤.①用M尺测出注射器针筒上全部刻度地长度L.②.③把适量地润滑油抹在注射器地活塞上，将活塞插入外筒中，上下拉动活塞，使活塞与针筒地间隙内均匀地涂上润滑油.④将活塞插到适当地位置.⑤.⑥在钩码框架两侧挂上钩码，记下挂上地钩码地质量m1.在达到平衡后，记下注射器中空气柱地体积V1.在这个过程中不要用手接触注射器以保证空气柱温度不变.⑦增加钩码地个数，使钩码地质量增大为m2，达到平衡后，记下空气柱地体积V2.<2）求出计算大气压强p0地公式.<用已给地和测得地物理量表示）：30．<27分）有三根长度皆为l＝1.00 m地不可伸长地绝缘轻线，其中两根地一端固定在天花板上地O点，另一端分别挂有质量皆为m＝1.00×10－2kg地带电小球A和B，它们地电量分别为一q和＋q，q＝1.00×10－7C.A、B之间用第三根线连接起来.空间中存在大小为E＝1.00×106N/C地匀强电场，场强方向沿水平向右，平衡时A、B球地位置如图所示.现将O、B之间地线烧断，由于有空气阻力，A、B球最后会达到新地平衡位置.求最后两球地机械能与电势能地总和与烧断前相比改变了多少.<不计两带电小球间相互作用地静电力）参考答案Ⅰ卷包括20小题，每题6分，共120分.15．B 16．C 17．D 18．B 19．B 20．DⅡ卷包括10个小题，共180分.26．<20分）将运动员看作质量为m地质点，从h1高处下落，刚接触网时速度地大小v1＝<向下）①弹跳后到达地高度为h2，刚离网时速度地大小v2＝<向上）②速度地改变量Δv＝v1＋v2<向上）③以a表示加速度，Δt表示接触时间，则Δv＝aΔt ④接触过程中运动员受到向上地弹力F和向下地重力mg.由牛顿第二定律，F－mg＝ma ⑤由以上五式解得，F＝mg＋m⑥代入数据得：F＝1.5×103N ⑦27．<20分）电子在磁场中沿圆弧ab运动，圆心为C，半径为R.以v表示电子进入磁场时地速度，m、e分别表示电子地质量和电量，则eU＝mv2①eVB＝②又有tg＝③由以上各式解得B＝④29．<37分）1．<17分）<1）称出活塞和钩码框架地总质量M将注射器针筒上地小孔用橡皮帽堵住<2）活塞地根截面积为S＝①由力学平衡条件得p1＝p0＋g ②p2＝p0＋g ③由玻意耳定律得p1V1＝p2V2④联立解得大气压强p0＝<）⑤30．<27分）右图中虚线表示A、B球原来地平衡位置，实线表示烧断后重新达到平衡地位置，其中α、β分别表示细线OA、AB与竖直方向地夹角.A球受力如右图所示：重力mg，竖直向下；电场力qE，水平向左；细线OA对A地拉力T1，方向如图；细线AB对A地拉力T2，方向如图.由平衡条件T1sinα＋T2sinβ＝qE ①T2cosα＝mg＋T2 cosβ②B球受力如右图所示：重力mg，竖直向下；电场力qE，水平向右；细线AB对B地拉力T2，方向如图.由平衡条件T2sinβ＝qE ③T2cosβ＝mg ④联立以上各式并代入数据，得α＝0 ⑤β＝45°⑥由此可知，A、B球重新达到平衡地位置如右图所示.与原来位置相比，A球地重力势能减少了E A＝mgl<1－sin60°）⑦B球地重力势能减少了E B＝mgl<1－sin60°＋cos45°）⑧A球地电势能增加了W A＝qElcos60°⑨B球地电势能减少了W B＝qEl<sin45°－sin30°）⑩两种势能总和减少了W＝W B－W A＋E A＋E B错误!代入数据解得W＝6.8×10－2J 错误!申明：所有资料为本人收集整理，仅限个人学习使用，勿做商业用途.。

2002年全国高考物理试题(附答案)

第页共 4 页1 2002年普通高等学校招生全国统一考试（全国卷）理科综合能力测试15．目前普遍认为，质子和中子都是由被称为u 夸克和d 夸克的两类夸克组成。

u 夸克带电量为32e ，d 夸克带电量31e ，e 为基元电荷。

下列论断可能正确的是 A 质子由1个u 夸克和1个d 夸克组成，中子由1个u 夸克和2个d 夸克组成B 质子由2个u 夸克和1个d 夸克组成，中子由1个u 夸克和2个d 夸克组成C 质子由1个u 夸克和2个d 夸克组成，中子由2个u 夸克和1个d 夸克组成D 质子由2个u 夸克和1个d 夸克组成，中子由1个u 夸克和1个d 夸克组成16、在光滑水平地面上有两个相同的弹性小球A 、B ，质量都为m 。

现B 球静止，A 球向B 球运动，发生正碰。

已知碰撞过程中总机械能守恒，两球压缩最紧时的弹性势能为E P ，则碰前A 球的速度等于A m E pB m E p 2C 2m E pD 2mE p 217．图中EF 、GH 为平行的金属导轨，其电阻可不计，R 为电阻器，C 为电容器，AB 为可在EF 和CH 上滑动的导体横杆。

有均匀磁场垂直于导轨平面。

若用I 1和I 2分别表示图中该处导线中的电流，则当横杆ABA 匀速滑动时，I 1＝0，I 2＝0B 匀速滑动时，I 1≠0，I 2≠0C 加速滑动时，I 1＝0，I 2＝0D 加速滑动时，I 1≠0，I 2≠018．质点所受的力F 随时间变化的规律如图所示，力的方向始终在一直线上。

已知t ＝0时质点的速度为零。

在图示t 1、t 2、t 3和t 4各时刻中，哪一时刻质点的动能最大？A t 1B t 2C t 3D t 419．为了观察门外情况，有人在门上开一小圆孔，将一块圆柱形玻璃嵌入其中，圆柱体轴线与门面垂直。

从圆柱底面中心看出去，可以看到的门外入射光线与轴线间的最大夹角称做视场角。

已知该玻璃的折射率为n ，圆柱长为l ，底面半径为r ，则视场角是A arcsin22nl r l + B arcsin 22nr r l + C arcsin 22rn r l + D arcsin 22l n r l +20．在如图所示的电路中，R 1、R 2、R 3和R 4皆为定值电阻，R 5为可变电阻，电源的电动势为ε，内阻为r 。

AP物理C真题2002

$3 Physics C: Mechanics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he following conventions are used in this examination.I. Unless otherwise stated, the frame of reference of any problem is assumed to be inertial.II. The direction of any electric current is the direction of flow of positive charge (conventional current).III. For any isolated electric charge, the electric potential is defined as zero at an infinite distance from the charge.ADVANCED PLACEMENT PHYSICS C EQUATIONS FOR 2002PHYSICS CSection II, MECHANICSTime—45 minutes3 QuestionsDirections: Answer all three questions. The suggested time is about 15 minutes for answering each of the questions, which are worth 15 points each. The parts within a question may not have equal weight. Show all your work in the pink booklet in the spaces provided after each part, NOT in this green insert.Mech 1.A crash test car of mass 1,000 kg moving at constant speed of 12 m/s collides completely inelastically with anobject of mass M at time t= 0. The object was initially at rest. The speed u in m/s of the car-object system after the collision is given as a function of time t in seconds by the expressionu=8.1+5t(a) Calculate the mass M of the object.(b) Assuming an initial position of x = 0, determine an expression for the position of the car-object system afterthe collision as a function of time t.(c) Determine an expression for the resisting force on the car-object system after the collision as a function oftime t.(d) Determine the impulse delivered to the car-object system from t= 0 to t= 2.0 s.Mech 2.The cart shown above is made of a block of mass m and four solid rubber tires each of mass m/4 and radius r.Each tire may be considered to be a disk. (A disk has rotational inertia 122ML, where M is the mass and L isthe radius of the disk.) The cart is released from rest and rolls without slipping from the top of an inclined plane of height h. Express all algebraic answers in terms of the given quantities and fundamental constants.(a) Determine the total rotational inertia of all four tires.(b) Determine the speed of the cart when it reaches the bottom of the incline.(c) After rolling down the incline and across the horizontal surface, the cart collides with a bumper of negligiblemass attached to an ideal spring, which has a spring constant k. Determine the distance x m the spring is compressed before the cart and bumper come to rest.(d) Now assume that the bumper has a non-neglible mass. After the collision with the bumper, the springis compressed to a maximum distance of about 90% of the value of x m in part (c). Give a reasonableexplanation for this decrease.Mech 3.An object of mass 0.5 kg experiences a force that is associated with the potential energy functionU x x()..=+4020, where U is in joules and x is in meters.(a) On the axes below, sketch the graph of U (x ) versus x .(b) Determine the force associated with the potential energy function given above.(c) Suppose that the object is released from rest at the origin. Determine the speed of the particle at x = 2 m.In the laboratory, you are given a glider of mass 0.5 kg on an air track. The glider is acted on by the forcedetermined in part (b). Your goal is to determine experimentally the validity of your theoretical calculation in part (c).(d) From the list below, select the additional equipment you will need from the laboratory to do your experimentby checking the line next to each item. If you need more than one of an item, place the number you need on the line. ___ Meterstick ___ Stopwatch ___ Photogate timer___ String___ Spring___ Balance___ Wood block___ Set of objects of different masses(e) Briefly outline the procedure you will use, being explicit about what measurements you need to makein order to determine the speed. You may include a labeled diagram of your setup if it will clarify your procedure.END OF SECTION II, MECHANICS。

大学物理C-02力学基本定律2参考答案 (1)

3.长 l 0.40m 、质量 M 1.00kg 的匀质木棒，可绕水平轴 O 在竖直平面内转动，开始时棒自然竖直悬垂，现有质量 m 8 g 的子弹以 v 200m / s 的速率从 A 点射入棒中，A 点与 O 点的距离为解：（1）应用角动量守恒定律
3 l ，如图所示。求：（1）棒开始运动时的角速度；（2）棒的最大偏转角。 4
（2）应用机械能守恒定律
A
l l 1 1 3 3l 3l [ Ml 2 m ( l )] 2 Mg mg Mg cos mg cos 2 3 4 2 4 2 4 2 9 M m 8 l 0.079 得 cos 1 3 2 M 3m g
4.一根放在水平光滑桌面上的匀质棒，可绕通过其一端的竖直固定光滑轴O 转动．棒的质量为m = 1.5kg，长度为l = 1.0 m，对轴的转动惯量为J =ml2/3 ．初始时棒静止．今有一水平运动的子弹垂直地射入棒的另一端，并留在棒中，如图所示．子弹的质量为m′= 0.020kg，速率为v =400 m·s-1．试问： (1)棒开始和子弹一起转动时角速度ω有多大？
8. 粒子在加速器中被加速，当加速到其质量为静止质量的 5 倍时，其动能为静止能量的__4__倍。二、选择题 1.一轻绳跨过一具有水平光滑轴、质量为M 的定滑轮，绳的两端分别悬有质量为m1 和m2 的物体(m1 ＜m2)，如图所示．绳与轮之间无相对滑动．若某时刻滑轮沿逆时针方向转动，则绳中的张力［ C ］ (A) 处处相等． (B) 左边大于右边． (C) 右边大于左边． (D) 哪边大无法判断． 2.将细绳绕在一个具有水平光滑轴的飞轮边缘上，现在在绳端挂一质量为m的重物，飞轮的角加速度
2
O 60

2002年试题及答案

LA物理师命题时间： 2002年 5月1：单个质子所带电荷若以库仑表示,则为选项：A. 1.60219⨯10-17B. 1.60219⨯10-18C. 1.60219⨯10-19D. 1.60219⨯10-20E. 1.60219⨯10-212：下列关于原子序数的论述中,哪一条是错误的选项：A. 表示该元素在周期表中的位置B. 表示原子核内质子数和中子数的多少C. 表示原子核外电子数的多少D. 表示原子核内质子数的多少E. 表示原子核电荷核数的多少3：在原子壳层模型中,主量子数n=3,轨道量子数l=2的壳层最多可容纳的电子数为每壳层最多容纳的电子数为2n2，同时满足2（2L+1）,但L<=n-1。

这要注意选项：A. 18B. 3C. 2D. 10E. 64：在原子壳层模型中,主量子数n=3,轨道量子数l=3的壳层最多可容纳的电子数为此时n=L,与L<=n-1矛盾，故次题D选项：A. 18B. 3C. 9D. 无此壳层E. 145： 1摩尔任何元素的物质包含多少个原子选项：A. 6.022⨯1023B. 6.022⨯1024C. 6.022⨯1025D. 6.022⨯1026E. 6.022⨯10276：当元素的原子序数大于一定数值时元素都是不稳定的,这个值是原子序数小于82的元素至少存在一种稳定核素，而大于82的都不稳定，会自发的放出α粒子或自发裂变成铅（82）的稳定同位素选项：A. 82B. 28C. 40D. 88E. 2067：给出下列哪种射线不是放射性核素发出的选项：A. α射线B. β射线C. X射线（机器产生）D. 正电子E. 中子8：下述论述中,哪一个不是β衰变选项：A. 原子核自发地放射出β-粒子（电子）B. 原子核自发地放射出β+粒子（正电子）C. K壳层的电子俘获D. M壳层的电子俘获（各层电子俘获）E. 光电子发射9：关于内转换机制的下列说法正确的是选项：A. 处于激发态的原子放出γ射线击出外层电子B. 处于激发态的原子退激时放出电子C. 处于激发态的原子核的β衰变D. 处于激发态的原子核把能量转移给轨道电子使其发射出原子来E. 处于激发态的原子核放出γ射线击出轨道电子10：后装治疗机的192Ir放射源的安装初始强度为10居里,若当强度低于2.5居里时停止使用,则最长的更换时间为2个半衰期半衰期74天；钴的是5.27年，能量为1.17和1.33MV选项：A. 3个月B. 4个月C. 5个月D. 6个月E. 7个月11：如下哪种粒子或射线可引起原子间接电离不带电粒子引起原子间接电离选项：A. 电子B. 质子C. α粒子D. 重离子E. X(γ)光子12：在放射治疗中所应用的电子束能量范围内,电子在组织中损失能量的首要方式为选项：A. 与组织中原子核外电子发生多次非弹性碰撞逐渐损失能量B. 与组织中原子核发生多次非弹性碰撞逐渐损失能量C. 与组织中原子核发生多次弹性碰撞逐渐损失能量D. 与组织中自由电子发生湮灭辐射一次损失全部能量E. 与组织中原子核发生核反应损失全部能量13：碰撞损失是描述下列哪一物理过程的能量损失选项：A. 带电粒子与原子核发生核反应B. 带电粒子与原子核发生弹性碰撞C. 带电粒子与原子核发生非弹性碰撞D. 带电粒子与原子核外电子发生非弹性碰撞E. 带电粒子与原子核外电子发生弹性碰撞14：辐射损失是描述下列哪一物理过程的能量损失选项：A. 带电粒子与原子核外电子发生弹性碰撞B. 带电粒子与原子核发生非弹性碰撞C. 带电粒子与原子核外电子发生非弹性碰撞D. 带电粒子与原子核发生弹性碰撞E. 带电粒子与原子核发生核反应15：带电粒子与重原子核发生弹性碰撞时,下列描述中错误的是选项：A. 带电粒子的运动方向和速度发生变化B. 相互作用可以是库仑是核力相相互作用也可以互作用C. 相互作用过程中原子核不激发不辐射光子D. 带电粒子能量低时弹性散射截面大E. 碰撞后绝大部分能量由原子核获得F. 碰撞后绝大部分能量由散射粒子带走16：对一定能量的特定带电粒子在相互作用过程中,其电离损失在哪一阶段最大选项：A. 相互作用的初始阶段B. 带电粒子损失一定能量之后C. 能量接近耗尽时D. 不同带电粒子有不同行为E. 整个相互作用过程中电离损失不变17：带电粒子与物质相互作用中,单位长度的电离损失用下述哪个物理量表示选项：A. 线性碰撞阻止本领B. 单位质量厚度的就是质量碰撞阻止本领（改了）C. 线性辐射阻止本领D. 质量辐射阻止本领E. 传能线密度18：如下哪一种射线(或粒子)的射线质是用射程表征中低能X线用HVL表示，放射性核素为如钴-60γ射线，高能X线用辐射质指数I表示，如TPR20/TPR10或PDD20/PDD10选项：A. 200KV X射线B. 400KV X射线C. 6MV X射线D. 10MV X射线E. 电子线19：射线与物质相互作用概率（截面）用巴恩表示,1巴恩等于多少平方厘米选项：A. 10-12B. 10-16C. 10-19D. 10-24E. 10-28M220：线性衰减系数（u=δn）是用来描述选项：A. X(γ)射线与物质相互作用中,单位长度的能量损失份额B. X(γ)射线与物质相互作用中,单位厚度物质发生相互作用概率C.带电粒子与物质相互作用中,单位长度发生相互作用几率D. 带电粒子与物质相互作用中,单位质量厚度的能量损失份额E. X(γ)射线与物质相互作用中,其强度衰减一半时的物质厚度F. 也表示光子束穿过靶物质时在单位厚度上入射光子数减少的百分数21：质量衰减系数是用来描述选项：A. 带电粒子与物质相互作用中,单位厚度的能量损失份额B. X(γ)射线与物质相互作用中,单位厚度的相互作用几率C. 带电粒子与物质相互作用中,单位质量厚度的能量损失份额D. X(γ)射线与物质相互作用中, 单位质量厚度的相互作用几率E. X(γ)射线与物质相互作用中,强度衰减一半时的物质厚度22：线性能量转移系数是用来描述选项：A. X(γ)射线与物质相互作用中,单位长度的能量损失份额B. 带电粒子与物质相互作用中,单位长度的能量损失份额C. X(γ)射线与物质相互作用中,单位长度的相互作用几率D. 带电粒子与物质相互作用中,单位质量厚度的能量损失份额E. X(γ)射线与物质相互作用中,单位质量厚度的相互作用几率23：质量能量转移系数是用来描述选项：A. X(γ)射线与物质相互作用中,单位长度的能量损失份额B. 带电粒子与物质相互作用中,单位长度的能量损失份额C. X(γ)射线与物质相互作用中,单位长度的相互作用几率D. 带电粒子与物质相互作用中,单位质量厚度的能量损失份额E. X(γ)射线与物质相互作用中,单位质量厚度的相互作用几率24：质能吸收系数是用来描述选项：A. X(γ)射线与物质相互作用中,单位长度的能量损失份额B. X(γ)射线与物质相互作用中,单位质量厚度的能量损失C. X(γ)射线与物质相互作用中,单位质量厚度被物质吸收的能量份额D. X(γ)射线与物质相互作用中,单位长度被物质吸收的能量份额E.带电粒子与物质相互作用中,单位质量被物质吸收的能量份额25： X(γ)射线在物质中的衰减服从指数衰减规律必须符合的条件是选项：A. 窄束B. 宽束C. 平行宽束D. 平行宽束和单一能量E. 平行窄束和单一能量26：下述哪个物理量不是用来描述X(γ)射线与物质相互作用的选项：A. 截面B. 线性衰减系数C. 半价层D. 平均自由程E. 实际射程（带电粒子）27：带电粒子和X(γ)射线在与物质相互作用中表现出不同的行为,下列对这些不同点的描述中错误的是选项：A. X(γ)射线不直接引起电离和激发B. 带电粒子在物质中有一定的射程, X(γ)射线没有C. X(γ)射线的射线质用射程表示,带电粒子的射线质用半价层表示D. 带电粒子通过多次相互作用逐渐损失能量E. X(γ)射线穿过物质厚度是指数衰减。

【AP物理C】【真题】2002年力学解答题答案

(1,000 kg )(12
1 point
(b)
3 points For any indication that the velocity u is the time derivative of position x dx 8 = dt 1 + 5t For correctly expressing the above equation as an integral, with or without using limits 8 x=ò dt 1 + 5t Substituting u = 1 + 5t and du = 5dt 8 du 8 8 x= ò = ln u + C = ln (1 + 5t ) + C (or equivalent using limits) 5 u 5 5 The condition x = 0 at t = 0 gives C = 0 For the correct answer 8 x = ln (1 + 5t ) 5 1 point
g = 10 m s 2 for ease of calculation, but use of 9.8 m s 2 is of course also acceptable.
2.
3.
4.
5.
Numerical answers that differ from the published answer due to differences in rounding throughout the question typically receive full credit. The exception is usually when rounding makes a difference in obtaining a reasonable answer. For example, in calculations of mass differences in a nuclear reaction, rounding to too few digits can lose the accuracy required to determine a mass difference.

2000年ap物理c力学答案

2000年ap物理c力学答案1、C.电源的电动势与外电路无关(正确答案)D.电源电动势等于内电压答案解析：ABC都正确，D选项电源的电动势= 电源两端没有接用电器时，用电压表测得的电压。

此时，E全部加在内阻r上（即：全部电压都分给内阻r）当电源接入电路中时，全部电压（电动势E）分为两部分：①内阻r分得的电压Ur （内电压）②外部电路分得的电压U （外电压）所以：“电动势为什么等于内外电压之和”即：E = Ur + U2、26．下列现象中，属于升华的现象是（）[单选题] *A．夏天，冰棍周围冒“白气”B．冬天，玻璃窗上结冰花C．衣箱中的樟脑丸逐渐变小(正确答案)D．夏天，水缸外壁“出汗”3、当0℃的冰熔化成0℃的水时，温度和内能都不变[判断题] *对错(正确答案)答案解析：温度不变，内能增大4、3．屋檐滴下的水滴下落可视为自由落体运动．[判断题] *对(正确答案)错5、错竹筷漂浮在水面上，是由于筷子受到的浮力大于自身重力[判断题] *对错(正确答案)答案解析：漂浮时浮力等于重力6、88．如图为甲、乙两种物质的m﹣V图像，下列说法中正确的是（）[单选题] *A．体积为15cm3的乙物质的质量为30g(正确答案)B．甲的质量一定比乙的质量大C．甲、乙体积相同时，乙的质量是甲的2倍D．甲、乙质量相同时，甲的体积是乙的2倍7、30．如图，我国首款国际水准的大型客机C919在上海浦东机场首飞成功，标志着我国航空事业有了重大突破。

它的机身和机翼均采用了极轻的碳纤维材料。

这种材料的优点是（）[单选题] *A．密度大B．密度小(正确答案)C．熔点低D．硬度小8、72．学习质量和密度的知识后，小明同学想用天平、量筒和水完成下列实验课题，你认为不能够完成的是（）[单选题] *A．测量牛奶的密度B．鉴别金戒指的真伪C．鉴定铜球是否空心D．测一捆铜导线的长度(正确答案)9、水平桌面上的文具盒在水平方向的拉力作用下，沿拉力的方向移动一段距离，则下列判断正确的是（）[单选题]A．文具盒所受拉力做了功(正确答案)B．文具盒所受支持力做了功C．文具盒所受重力做了功D．没有力对文具盒做功10、用丝绸摩擦过的玻璃棒能吸引纸屑，说明玻璃棒有磁性[判断题] *对错(正确答案)答案解析：玻璃棒带电可以吸引轻小物体11、69．两种不同材料制成的大小相同的实心球甲、乙，在天平右盘中放入4个甲球，在左盘中放入5个乙球，这时天平刚好平衡，且游码没有移动，则可知（）[单选题] *A．甲球和乙球质量之比为5：1B．甲球和乙球质量之比为4：5C．甲球和乙球密度之比为5：4(正确答案)D．甲球和乙球密度之比为4：512、8．将耳朵贴在长铁水（管中有水）管的一端，让另外一个人敲击一下铁水管的另一端。

2002年普通高等学校春季招生全国统一考试物理试卷及答案

2002年普通高等学校春季招生全国统一考试物理部分第I卷<选择题）本卷共24题，每题6分。

在下列各题的四个选项中，只有一个选项是符合题目要求的。

16．下列四个选项的图中，木块均在固定的斜面上运动，其中图A、B、C中的斜面是光滑的，图D中的斜面是粗糙的，图A、B中的F 为木块所受的外力，方向如图中箭头所示，图A、B、D中的木块向下运动，图C中的木块向上运动，在这四个图所示的运动过程中机械能守恒的是wZOVLt2lO3A B C D17．如图所示，在两个固定电荷＋q和－q之间放入两个原来不带电的导体，1、2、3、4为导体上的四个点，在达到静电平衡后，各点的电势分别是φ1、φ2、φ3、φ4，则wZOVLt2lO3A φ4＞φ3＞φ2＞φ1B φ4＝φ3＞φ2＝φ1C φ4＜φ3＜φ2＜φ1D φ4＝φ3＜φ2＝φ118．图中所示为一简谐横波在某一时刻的波形图，已知此时质点A正向上运动，如图中箭头所示，由此可断定此横波wZOVLt2lO3A 向右传播，且此时质点B正向上运动B 向右传播，且此时质点C正向下运动C 向左传播，且此时质点D正向上运动D 向左传播，且此时质点E正向下运动19．氢原子的能级是氢原子处于各个定态时的能量值，它包括氢原子系统的电势能和电子在轨道上运动的动能，氢原子的电子由外层轨道跃迁到内层轨道时，wZOVLt2lO3A 氢原子的能量减小，电子的动能增加B 氢原子的能量增加，电子的动能增加C 氢原子的能量减小，电子的动能减小D 氢原子的能量增加，电子的动能减小20．在高速公路上发生一起交通事故，一辆质量为1500kg向南行驶的长途客车迎面撞上了一质量为3000kg向北行驶的卡车，碰后两车接在一起，并向南滑行了一小段距离后停止，根据测速仪的测定，长途客车碰前以20m/s的速率行驶，由此可判断卡车碰前的行驶速率wZOVLt2lO3A 小于10m/sB 大于10m/s小于20m/sC 大于20m/s小于30m/sD 大于30m/s小于40m/s21．图为云室中某粒子穿过铅板P前后的轨迹，室中匀强磁场的方向与轨迹所在平面垂直<图中垂直于纸面向里，）由此可知此粒子wZOVLt2lO3A 一定带正电 B 一定带负电C 不带电D 可能带正电，也可能带负电22．图中L 是凸透镜，OO ′是它的主轴，AB 是垂直于主轴的肖源，P 是垂直于主轴的光屏，当两者到透镜的距离相等时，在光屏上得到清晰的像，如将AB 向右移动任意一段距离后，再移动P ，则在P 上wZOVLt2lO3A 总能得到缩小的像 B 总能得到较大的像C 可能得到放大的像，也可能得到缩小的像D 可能得到放大的像，也可能得不到像23．质量为m 的三角形木楔A 置于倾角为θ的固定斜面上，它与斜面间的动摩擦因数为μ，一水平力F 作用在木楔A 的竖直平面上，在力F 的推动下，木楔A 沿斜面以恒定的加速度a 向上滑动，则F 的大小为：wZOVLt2lO3Aθθμθcos )]cos (sin [++g a m B )sin (cos )sin (θμθθ+-g a m C )sin (cos )]cos (sin [θμθθμθ-++g a m D )sin (cos )]cos (sin [θμθθμθ+++g a m 24．一个点源S 对平面镜成像，设光源不动，平面镜以速率v 沿OS 方向向光源平移，镜面与OS 方向之间的夹角为30º，则光源的像S′将wZOVLt2lO3A 以速率0.5v沿S′S连线向S运动B 以速率v沿S′S连线向S运动C 以速率3v沿S′S连线向S运动D 以速率2v沿S′S连线向S运动第II卷<非选择题）29．<18分）图甲、乙是两组同样的器材实物图，用来测量待测电阻R的阻值，每组器材中包括：电池，电键，变阻器，电压表，电流表，等测电阻R，若干导线。

物理_2002年全国统一高考物理试卷(广东、广西)_复习

2002年全国统一高考物理试卷（广东、广西）一、本大题共4道选择题，每题3分，共12分．每题有一个最符合题目要求的答案．1. 如图为一弹簧振子的振动图像，由此可知（）A 在t 1时刻，振子的动能最大，所受的弹性力最大B 在t 2时刻，振子的动能最大，所受的弹性力最小C 在t 3时刻，振子的动能最大，所受的弹性力最小D 在t 4时刻，振子的动能最大，所受的弹性力最大2. 已知一束单色光在水中的传播速度是真空中的34，则（） A 这束光在水中传播时的波长为真空中的34B 这束光在水中传播时的频率为真空中的34C 对于这束光，水的折射率为34D 从水中射向水面的光线，一定可以进入空气中 3. 如图示，在匀强磁场中有一U 形导线框abcd ，线框处于水平面内，磁场与线框平面垂直，R 为一电阻．ef 为垂直于ab 、cd 的一根导体杆，可以在ab 、cd 上无摩擦地滑动．杆ef 及线框的电阻均不计．开始时，给ef 一个向右的初速度v 0，则（）A ef 将减速向右运动，但不是匀减速B ef 将匀减速向右运动，最终停止C ef 将匀速向右运动D ef 将往返运动4. 将甲、乙两物体自地面同时上抛，甲的质量为m ，初速为v ，乙的质量为2m ，初速为v 2．若不计空气阻力，则（）A 甲比乙先到最高点B 甲和乙在最高点的重力势能相等C 落回地面时，甲的动量的大小比乙的大D 落回地面时，甲的动能比乙的大二、解答题（共1小题，满分9分）5. 在其他能源中，核能具有能量密度大，地区适应性强的优势．在核电站中，核反应堆释放的核能被转化为电能．核反应堆的工作原理是利用中子轰击重核发生裂变反应，释放出大量核能．在其他能源中，核能具有能量密度大，地区适应性强的优势．在核电站中，核反应堆释放的核能被转化为电能．核反应堆的工作原理是利用中子轰击重核发生裂变反应，释放出大量核能．(1)核反应方程式 23592 U +n → 14156 Ba + 9236 Kr +aX 是反应堆中发生的许多核反应中的一种，n 为中子，X 为待求粒子，a 为X 的个数，则X 为________，a =________．以m U 、m_B a 、m kr 分别表示 23592 U、 14156 Ba、 9236 Kr核的质量，m n、m p分别表示中子、质子的质量，c为光在真空中传播的速度，则在上述核反应过程中放出的核能△E=________．(2)有一座发电能力为P=1.00×106kW的核电站，核能转化为电能的效率η=40%．假定反应堆中发生的裂变反应全是本题(1)中的核反应，已知每次核反应过程放出的核能△E=2.78×10−11J， 23592 U核的质量m U=390×10−27kg．求每年(1年=3.15×107s)消耗的 23592 U的质量．2002年全国统一高考物理试卷（广东、广西）答案1. B2. A3. A4. D5. 中子,3,(m u−m Ba−m Kr−2m n)c2。