PhysicsBowl_2002_Results

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2018PhysicsBowl物理碗真题及答案解析

ground. Ignoring air resistance, what is the speed of the ball when it reaches the ground?
(A) 18.5 m/s
(B) 14.6 m/s (C) 14.0 m/s (D) 12.8 m/s (E) 12.0 m/s
o Division 1 is for students taking physics for the first time (even if that first course is AP Physics). o Division 2 is for students taking a second (or more) course in physics or anyone wanting a challenge.
Your School’s CEEB code (given to you by your teacher), though not required, IS helpful in the event of a disqualification for identifying your school.
INSTRUCTIONS Answer sheet: Write and bubble-in the following REQUIRED information on your answer sheet:
Your Name
Your Teacher’s AAPT Teacher code (given to you by your teacher – only one code per school!)
(A) 2.9%
(B) 6.3%
(C) 8.7%

第2届国际物理奥林匹克竞赛试题及解答

第2届国际物理奥林匹克竞赛试题与解答（1968年于匈牙利的布达佩斯）【题１】在倾角为300的斜面上，质量为m 2＝4 kg 的木块经细绳与质量为m 1＝8 kg 、半径为r ＝5 cm 的实心圆柱体相连。

求放开物体后的加速度。

木块与斜面之间的动摩擦系数μ＝0.2，忽略轴承的摩擦和滚动摩擦。

解：如果绳子是拉紧，则圆柱体与木块一同加速运动，设加速度为a ，绳子中的张力为F ，圆柱体与斜面之间的摩擦力为S ，则圆柱体的角加速度为a ／r 。

对木块有：m 2a ＝m 2g sin α－μm 2g cos α＋F对圆柱体有：m 1a ＝m 1g sin α－S －FS r ＝Ia ／r其中I 是圆柱体的转动惯量，S r 是摩擦力矩。

解以上方程组可得221221cos sin )(rI m m m m m g a ++-+=αμα （1） 2212212cos sin )(rI m m m m m g r I S ++-+=αμα （2） 2212212sin cos )(rI m m r I r I m g m F ++-+=ααμ （3）均匀圆柱体的转动惯量为221r m I = 代入数据可得a ＝0.3317g ＝3.25m/s 2S ＝13.01 NF ＝0.196 N讨论：系统开始运动的条件是a ＞0。

把a ＞0代入（1）式，得出倾角的极限α1为： ==+=3tan 2121μμαm m m 0.0667 α1＝3049/单从圆柱体来看，α1＝０；单从木块来看，α1＝tg -1μ＝11019/如果绳子没有拉紧，则两物体分开运动，将F ＝0代入（3）式，得出极限角为：==+=μμα3)1(t a n 212Ir m 0.6 m 1m 2aα2＝30058/圆柱体开始打滑的条件是S 值（由（2）式取同样的动摩擦系数算出）达到μ m 1g cos α，由此得出的α3值与已得出的α2值相同。

圆柱体与木块两者的中心加速度相同，都为g （sin α－μ g cos α）圆柱体底部的摩擦力为μ m 1g cos α，边缘各点的切向加速度为 a ＝μ（Ir m 21）g cos α，【题2】一个杯里装有体积为300 cm 3、温度为00C 的甲苯，另一个杯里装有体积为110 cm 3、温度为1000C 的甲苯，两体积之和为410 cm 3。

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。

PhysicsBowl物理碗美国高中物理竞赛-2009-Exam考试

14. How much work is done by the applied force, F , to the box?
(A) 2400 J (B) 1920 J (C) 1200 J (D) 988.5 J (E) − 187.5 J
15. An ideal gas in a closed container of volume 6.0 L is at a temperature of 100 °C . If the pressure of the gas is 2.5 atm , how many moles of gas are in the container?
ATTENTION:
All Division 01 students, START HERE. All Division 02 students – skip the first 10 questions, begin on # 11.
1. Approximately how many seconds is it until the PhysicsBowl takes place in the year 2109 ?
(A) 6 (B) 5 (C) 4 (D) 3 (E) 2
5. At an instant of time, a block of mass 0.50 kg has a position of 3.0 m , a speed of 4.0 m , and s an acceleration of 1.0 m 2 . What is the block’s kinetic energy (in Joules) at this instant? s
s
the bottom of a rough, fixed inclined plane. The box slides with constant acceleration to the top of the incline as it is being pushed directly to the left with a constant force of F = 240 N . The box, of mass m = 20.0 kg , has a speed of 2.50 m it reaches the top of the incline.

高质量高中生物理竞赛汇总

高质量高中生物理竞赛汇总大家好，今天习美君为大家整理了高质量高中生国际物理竞赛汇总另外文末还有比赛讲座福利，不要错过。

事不宜迟，我们直接进入干货板块。

物理杯 Physics Bowl竞赛简介：Physics Bowl竞赛是全美极具影响力的高中物理思维挑战活动，由权威的美国物理教师协会（The American Association of Physics Teachers ，简称AAPT）主办。

AAPT成立于1930年，该协会旗下有8000名注册物理老师，其中一半成员是美国各名牌大学物理教授，约三分之一成员是美国高中的有经验的物理老师。

协会每年都会通过会议、论坛、杂志、活动等方式为美国大学与高中物理教育提供新鲜的物理前沿思想与更丰富的物理教育资源。

考题由协会注册的大学物理教授和具有丰富教学经验的高中物理教师组成的理事会进行呈现和评价。

这个项目是美国非常有影响力的高中物理思维挑战活动。

每年全球11个国家500多所名校参与其中，数万名选手全球排名。

在这个项目中获得高分的人受到美国名校的欢迎，获胜者将被邀请参加世界顶级的科学活动和研究项目。

九年来，只有一个高中生在这个项目上得了满分。

语言：英文报名截止时间：2022年3月16日比赛时间：2022年3月26日（周六）下午14:00—14:45（45分钟）比赛方式：个人比赛，试卷笔试，没有实验考试资格：任意年级高中生难度：题目分为两套，高一学生（IB10年级，A-level的G1年级部分优秀学生和G2年级）建议选择Division1考题，高二、高三学生（IB11-12年级，A-level年级）建议选择Division2考题。

Division2难度大于Division1地点：内容：40道单选题，持续45分钟奖项设置：（Division1和Division2分开排名）个人奖：•全球个人奖-全球排名前 100 名•全国获胜个人奖-全国前10名•区域获胜个人奖-区域前10名•全国金奖-全国排名前10%•全国银奖-全国排名前25%•全国铜奖-全国排名前35%•物理优秀奖-各区排名（除全国奖项外）前20%团队奖：（每个学校无论人数多少，取本校个人成绩前 5 名加总为团体总分；若不足 5 人，则所有选手得分加总为团体分）•全球获胜团队奖-全球排名前 50 位•全国获胜团队奖-全国前 10 名•区域获胜团队奖-区域前 10 名官网链接：中国区官网：普林斯顿大学物理竞赛 Princeton University Physics Competition竞赛简介：普林斯顿大学物理竞赛是一项面向国际高中生的物理竞赛，由普林斯顿大学物理系和天体物理系组织。

体育测试后的感悟,英语作文二百字

体育测试后的感悟,英语作文二百字Reflecting upon the recently concluded physical fitness test, a myriad of emotions and insights come to mind. While the physical exertion was undoubtedly demanding, it served as a valuable opportunity for self-assessment and introspection.At the outset, the test ignited within me a sense of trepidation. The prospect of measuring my physical capabilities against established standards filled me with both anticipation and apprehension. However, as I embarked on the various exercises, I discovered a newfound determination within myself. Each obstacle presented an opportunity to push my limits and challenge my perceived boundaries.The results of the test provided both affirmation and areas for improvement. While I achieved satisfactory scores in some disciplines, others revealed room for growth. This realization served as a catalyst for reflection, promptingme to identify areas where I could enhance my physical fitness regime.Beyond the physical outcomes, the test also illuminated the importance of mental fortitude. The challenges encountered throughout the assessment required not only physical strength but also the ability to stay focused, maintain composure, and overcome setbacks. The fortitude I demonstrated during the test is a testament to the power of perseverance and the resilience of the human spirit.Furthermore, the test fostered a sense of camaraderie among the participants. As we shared in the collective experience of pushing ourselves to the limit, a bond of shared endeavor and mutual respect was formed. The encouragement and support provided by fellow participants served as a constant source of motivation.In the aftermath of the test, I am filled with a profound sense of gratitude for the opportunity to participate. The experience has taught me valuable lessons about my physical abilities, mental resilience, and thevalue of perseverance. It has also instilled within me a renewed determination to continue pursuing a healthy and active lifestyle.As I look to the future, I recognize that the physical fitness test was not merely an isolated event but a catalyst for ongoing growth and improvement. The insights gained and the spirit of determination cultivated will serve me well as I strive for continued progress in all aspects of my life.。

2023年物理碗题目

2023年物理碗题目【原创版】目录1.2023 年物理碗竞赛概述2.竞赛的难度和范围3.竞赛的报名和考试时间4.竞赛的奖项设置和意义正文【2023 年物理碗竞赛概述】2023 年物理碗竞赛，全名为全国中学生物理竞赛（National Physics Bowl），是由美国物理教师协会（American Association of Physics Teachers，简称 AAPT）主办的一项面向全球中学生的物理学科竞赛活动。

该竞赛自 1984 年起，已经成功举办 39 届，吸引了来自全球各地的中学生参加。

【竞赛的难度和范围】2023 年物理碗竞赛的难度分为 Division 1（初级组）和 Division 2（高级组）两个级别。

其中，初级组适合刚接触物理学科的中学生参加，高级组则更适合已经具备一定物理基础的学生挑战。

竞赛的范围涵盖了力学、热学、光学、电磁学等多个物理学领域，旨在全面测试参赛选手的物理知识储备和应用能力。

【竞赛的报名和考试时间】2023 年物理碗竞赛的报名时间预计为 2022 年 12 月，具体报名方式和流程可关注 AAPT 官方网站的公告。

考试时间则安排在 2023 年 3 月，具体考试日期和地点将在报名结束后进行通知。

值得注意的是，参赛选手需在规定时间内完成报名和交纳报名费用，否则将视为自动放弃参赛资格。

【竞赛的奖项设置和意义】2023 年物理碗竞赛的奖项设置分为个人奖和团队奖两类。

个人奖根据参赛选手的实际成绩进行评定，分为金、银、铜三个等级；团队奖则根据参赛团队的整体表现进行评定，设置有冠军、亚军、季军等奖项。

参加物理碗竞赛对于中学生来说具有重要意义，不仅可以锻炼自己的物理学术能力，还可以为今后的学习和发展积累宝贵经验。

武汉二中广雅中学八年级下册期末物理试卷含答案

武汉二中广雅中学八年级下册期末物理试卷含答案一、选择题1．下列估测的数据中，最接近实际情况的是（）A．八年级学生所受的重力大约为500NB．八年级学生游泳时排开水的体积约为0.5m³C．八年级学生立定跳远的成绩一般为5m左右D．“六一”儿童节期间小朋友玩耍的充气气球内的气压大约为0.8×105N/m²2．下列有关力的说法中，正确的是（）A．压力的方向总是竖直向下的B．力的作用效果与力的大小、方向和作用点都有关系C．手拍桌子时，手对桌子施加了力，桌子对手没有施加力D．弹簧被拉伸时产生的力是弹力，钢丝绳悬挂重物的拉力不是弹力3．在探究得出牛顿第一定律后，小组同学展开了讨论，其中，你支持的说法是（）A．牛顿第一定律是由实验探究直接得出的B．牛顿第一定律是由牛顿首先提出，并由伽利略等人总结出来的C．篮球不受力作用时运动状态将不会改变D．正在滚动的足球所受到的力突然消失了，它将停止4．日常生活很多实例需要改变压强，下图所示的实例中，是为了增大压强的是（）A．斧刃磨得很锋利B．坦克装有宽大的履带C．在铁轨下铺枕木D．书包背带做得很宽5．如图所示，不计滑轮重力及摩擦，已知物体A 质量为2kg ；物体B 质量为5kg ，体积为103 cm 3。

先用手握住A ，待放手后（）A ．物体B 将沉入水底B ．物体B 将停留在水面下任何地方C ．物体B 将离开水面上升D ．物体B 最后浮在水面上6．如图所示，在调节平衡后的杠杆两侧，分别挂上相同规格的钩码，杠杆处于平衡状态。

如果两侧各去掉一个钩码，则杠杆（）A ．仍然平衡B ．右端下降C ．左端下降D ．无法判断7．实心正方体木块（不吸水）漂浮在水上，如图所示，此时浸入水中的体积为43610m -⨯，然后在其上表面放置一个重4N 的铝块，静止后木块上表面刚好与水面相平（g取10N /kg ，331.010kg /m ρ=⨯水）则该木块（）①木块重力是10N②木块的体积是330.610m -⨯③木块的密度是330.610kg /m ⨯④放置铝块后，木块下表面受到水的压强增大了400PaA ．只有①②B ．只有②③C ．只有③④D ．只有②④8．原长为l 的橡皮筋一端固定在O 点，另一端悬挂一个小钢球，将钢球从O 点释放，钢球运动到A 点后开始向上返回，O 、A 两点间距离为2l ，如图所示。

物理ib高一考试试卷

物理ib高一考试试卷一、选择题（每题2分，共20分）1. 一个物体的质量是2千克，如果将其质量增加到3千克，其惯性将如何变化？A. 减少B. 增加C. 不变D. 不确定2. 根据牛顿第二定律，力和加速度之间的关系是什么？A. 力等于加速度乘以质量B. 力等于质量除以加速度C. 力等于加速度除以质量D. 力等于质量乘以加速度3. 以下哪个物理量是标量？A. 速度B. 加速度C. 力D. 温度4. 一个物体从静止开始自由落体，其下落的位移与时间的关系是什么？A. 位移与时间成正比B. 位移与时间的平方成正比C. 位移与时间的立方成正比D. 位移与时间的四次方成正比5. 以下哪个不是物体的机械能守恒的条件？A. 只有重力作用B. 物体只受摩擦力作用C. 物体只受弹簧弹力作用D. 物体只受拉力作用6. 根据能量守恒定律，以下哪个说法是正确的？A. 能量可以被创造或消灭B. 能量可以在不同形式之间转换C. 能量可以在不同物体之间转移D. 所有选项都是正确的7. 以下哪个选项描述的是波的干涉现象？A. 波的叠加B. 波的反射C. 波的衍射D. 波的折射8. 根据欧姆定律，电阻、电流和电压之间的关系是什么？A. 电阻等于电流除以电压B. 电阻等于电压除以电流C. 电流等于电阻除以电压D. 电压等于电流乘以电阻9. 一个物体在水平面上以恒定速度运动，以下哪个物理量是不变的？A. 速度B. 加速度C. 动能D. 势能10. 以下哪个是电磁波的属性？A. 传播速度等于光速B. 需要介质传播C. 只具有能量D. 不能携带信息二、填空题（每空1分，共10分）11. 牛顿第一定律又称为______。

12. 一个物体的动能与其质量和速度的平方成正比，其公式为______。

13. 根据热力学第一定律，能量守恒的公式为______。

14. 电磁波谱中，波长最长的是______，波长最短的是______。

15. 一个电路中，如果电流为2安培，电阻为5欧姆，根据欧姆定律，该电路中的电压为______伏特。

八年级英语科学实验步骤完形填空题30题答案解析版

八年级英语科学实验步骤完形填空题30题答案解析版1First, we need to prepare the materials for the experiment. We take a beaker, some water, and a few drops of food coloring. Then, we ___ the water into the beaker. After that, we add the food coloring carefully. Next, we observe the changes in the water. Finally, we record our findings.1. What should we do with the water?A. pourB. drinkC. throwD. save答案：A。

pour 表示“倾倒”，符合把水倒进烧杯的动作；drink 是“喝”，throw 是“扔”，save 是“保存”，都不符合实验步骤中的动作。

这里考查了动词的词义辨析。

2. After adding the food coloring, we should ___ the changes.A. ignoreB. avoidC. observeD. forget答案：C。

observe 表示“观察”，符合实验步骤中观察水的变化；ignore 是“忽视”，avoid 是“避免”，forget 是“忘记”，都不符合语境。

这里考查了动词的词义辨析。

3. Before adding the food coloring, we need to ___ the water carefully.A. heatB. coolC. pourD. taste答案：C。

上文提到把水倒进烧杯，所以这里在加食用色素之前需要小心地倒（pour）水；heat 是“加热”，cool 是“冷却”，taste 是“品尝”，都不符合实验步骤。

物理碗大赛physicsbowl2007

物理碗⼤赛physicsbowl2007ATTENTION: All Division I students, continue through question 40.All Division II students, START HERE. Numbers 1-10 on youranswer sheet should remain blank. Your first answer should benumber 11.11. A cart is initially moving at 0.5 m/s along a track. The cart comes to rest after traveling 1 m. The experiment is repeated on the same track, but now the cart is initially moving at 1 m/s. How far does the cart travel before coming to rest?(a) 1 m (b) 2 m (c) 3 m (d) 4 m (e) 8 m12. The definition of average velocity is(a) the average acceleration multiplied by the time.(b) distance traveled divided by the time.(c) ()021v v f +. (d) radius multiplied by angular velocity.(e) displacement divided by the time.13. A student weighing 500 N stands on a bathroom scale in the school’s elevator. When the scale reads 520 N, the elevator must be(a) accelerating upward.(b) accelerating downward.(c) moving upward at a constant speed.(d) moving downward at a constant speed.(e) at rest.14. An object moves to the East across a frictionless surface with constant speed. A person then applies a constant force to the North on the object. What is the resulting path that the object takes?(a) A straight line path partly Eastward, partly Northward(b) A straight line path totally to the North(c) A parabolic path opening toward the North(d) A parabolic path opening toward the East(e) An exponential path opening upward toward the NorthTwo identical mass objects are launched with the same speed from the same starting location. Object 1 is launched at an angle of 300 above the horizontal while Object 2 is60above the horizontal. Ignore air resistance and consider the launched at an angle of 0flight of each object from launch until it returns to the same launch height above the ground. Questions 15 and 16 refer to this situation.15.Which object returns to the starting height with the greatest speed?(a)Object 1 since it keeps a lower trajectory.(b)Object 2 since it is in the air for a longer time.(c)Object 2 since there is more work done on the object during flight(d)The speeds are the same.(e)It cannot be determined without more information.16.Which object experiences the greatest change in the linear momentum?(a)Object 1 since it has a higher final speed.(b)Object 2 since it has a higher final speed.(c)Object 2 since it is in the air for a longer time.(d)The change in momentum is the same for each.(e)It cannot be determined without more information.17.A toy car moves along the x-axis according tothe velocity versus time curve shown to theright. When does the car have zeroacceleration?(a)at 2 and 4 seconds(b)at approximately 3.0 seconds(c)at approximately 3.3 and 5.1 seconds(d)the acceleration is always zero(e)at no time18.In which one of the following situations is the net force constantly zero on the object?(a)A mass attached to a string and swinging like a pendulum.(b)A stone falling freely in a gravitational field.(c)An astronaut floating in the International Space Station.(d)A snowboarder riding down a steep hill.(e)A skydiver who has reached terminal velocity.19.What net force is necessary to keep a 1.0 kg puck moving in a circle of radius 0.5 m ona horizontal frictionless surface with a speed of 2.0 m/s?(a) 0 N (b) 2.0 N (c) 4.0 N (d) 8.0 N (e) 16 N20.A large wedge rests on a horizontal frictionlesssurface, as shown. A block starts from rest andslides down the inclined surface of the wedge,which is rough. During the motion of the block,the center of mass of the block and wedge system(a)does not move.(b)moves vertically with increasing speed.(c)moves horizontally with constant speed.(d)moves horizontally with increasing speed.(e)moves both horizontally and vertically.21.A box slides to the right across a horizontal floor. A person called Ted exerts a force Tto the right on the box. A person called Mario exerts a force M to the left, which is half as large as the force T. Given that there is friction f and the box accelerates to the right, rank the sizes of these three forces exerted on the box.f<<M(a)TM<<f(b)TM<<T(c)ff<=M(d)T(e)It cannot be determined.22.A mass m is pulled outward until the string of length L to which it is attached makes a90-degree angle with the vertical. The mass is released from rest and swings through a circular arc. What is the tension in the string when the mass swings through the bottom of the arc?3mg(e) It cannot be determined.(a) 0 (b) mg(c) 2mg (d)23.The period of a mass-spring system undergoing simple harmonic oscillation is T. If theamplitude of the mass-spring system’s motion is doubled, the period will be(a) ? T (b) ? T (c) T (d) 2T(e) 4T24. A resonance occurs with a tuning fork and an air column of size39 cm. The next highest resonance occurs with an air column of65 cm. What is the frequency of the tuning fork? Assume that thespeed of sound is 343 m/s.(a) 329.8 Hz(b) 527.7 Hz(c) 659.6 Hz(d) 879.5 Hz(e) 1319 Hz25. If two protons are spaced by a distance R, what is the ratio of the gravitational force that one proton exerts on the other to the electric force that one proton exerts on the other? That is,=electricgravity F F(a) 810?≈ (b) 1610?≈ (c) 2010?≈ (d) 3610?≈ (e) 4310?≈26. For the diagram shown below, what is the ratio of the charges 12q q , where the diagram shown has a representation of the field lines in the space near the charges.(a) 23? (b) 32? (c) 32 (d) 23 (e) 1C D 10 V 27. A junior Thomas Edison wants to make a brighter light bulb. He decides to modify the filament. How should the filament of a light bulb be modified in order to make the light bulb produce more light at a given voltage?(a) Increase the resistivity only.(b) Increase the diameter only.(c) Decrease the diameter only.(d) Decrease the diameter and increase the resistivity.(e) Increase the length only.28. Which statement about a system of point charges that are fixed in space is necessarily true?(a) If the potential energy of the system is negative, net positive work by an external agent is required to take the charges in the system back to infinity.(b) If the potential energy of the system is positive, net positive work is required to bring any new charge not part of the system in from infinity to its final resting location.(c) If the potential energy of the system is zero, no negative charges are in the configuration.(d) If the potential energy of the system is negative, net positive work by an external agent was required to assemble the system of charges.(e) If the potential energy of the system is zero, then there is no electric force anywhere in space on any other charged particle not part of the system.29.(a) A(b) B (c) C(d) D (e) The bulbs all have the same brightness.30. In the following circuit diagram, which one of the bulbs will not light?(a) A(b) B(c) C (d) D (e) They all light.C31.James Clerk Maxwell's great contribution to electromagnetic theory was his idea that(a)work is required to move a magnetic pole through a closed path surrounding a current.(b)a time-changing electric field acts as a current and produces a magnetic field.(c)the speed of light could be determined from simple electrostatic and magnetostatic experiments and finding the values of µo and εo.(d)the magnetic force on a moving charge particle is perpendicular to both its velocity and the magnetic field.(e)magnetism could be explained in terms of circulating currents in atoms.32.What does LASER stand for?(a)Light Amplification by Simulated Emission of Radiation(b)Light Amplification by Stimulated Emission of Radiation(c)Light Amplification by Simultaneous Emission of Radiation(d)Light Amplification by Systematic Emission of Radiation(e)Light Amplification by Serendipitous Emission of Radiation33.For the circuit shown, the ammeter reading isinitially I. The switch in the circuit then is closed.Consequently:(a)The ammeter reading decreases.(b)The potential difference between E and Fincreases.(c)The potential difference between E and Fstays the same.(d)Bulb #3 lights up more brightly.(e)The power supplied by the battery decreases.34.For the solenoids shown in the diagram (which areassumed to be close to each other), the resistance ofthe left-hand circuit is slowly increased. In whichdirection does the ammeter needle (indicating thedirection of conventional current) in the right-handcircuit deflect in response to this change?(a)The needle deflects to the left.(b)The needle deflects to the right.(c)The needle oscillates back and forth.(d)The needle rotates in counterclockwise circles.(e)The needle never moves.35.Two objects labeled K and L have equal mass but densities 0.95D0 and D0,respectively. Each of these objects floats after being thrown into a deep swimming pool. Which is true about the buoyant forces acting on these objects?(a)The buoyant force is greater on Object K since it has a lower density and displacesmore water.(b)The buoyant force is greater on Object K since it has lower density and lowerdensity objects always float “higher” in the fluid.(c)The buoyant force is greater on Object L since it is denser than K and therefore“heavier.”(d)The buoyant forces are equal on the objects since they have equal mass.(e)Without knowing the specific gravity of the objects, nothing can be determined.36.A driveway is 22.0 m long and 5.0 m wide. If the atmospheric pressure is 1.0 x 105 Pa,what force does the atmosphere exert on the driveway?(a)9.09 x 10-8 N(b) 1.1 x 10-3N(c)909 N(d)4545 N(e) 1.1 x 107 N37.A place of zero displacement on a standing wave is called(a)an antinode.(b)a node.(c)the amplitude.(d)the wavenumber.(e)the harmonic.38.Absolute zero is best described as that temperature at which(a)water freezes at standard pressure.(b)water is at its triple point.(c)the molecules of a substance have a maximum kinetic energy.(d)the molecules of a substance have a maximum potential energy.(e)the molecules of a substance have minimum kinetic energy.10. The 39.A mass of material exists in its solid form at its melting temperature C0following processes then occur to the material:Process 1: An amount of thermal energy Q is added to the material and ? of the material melts.Process 2: An identical additional amount of thermal energy Q is added to the material and the material is now a liquid at 500 C.What is the ratio of the latent heat of fusion to the specific heat of the liquid for this material?80(a)C060(b)C040(c)C020(d)C0(e)More information is needed to answer this question.40.Which is not true of an isochoric process on an enclosed ideal gas in which thepressure decreases?(a)The work done is zero.(b)The internal energy of the gas decreases.(c)The heat is zero.(d)The rms speed of the gas molecules decreases.(e)The gas temperature decreases.。

PhysicsBowl物理杯美国物理竞赛考试FAQ

Physics Bowl 物理杯美国物理竞赛考试 FAQ1.这个比赛谁主办的？A:比赛主办方是美国AAPT协会。

这个协会负责在美国组织举办中学生的物理竞赛，组织物理老师的培训等等。

更重要的是这个协会负责每年组织美国奥林匹克物理竞赛队伍。

Physics Bowl 物理杯是他们举办的比赛之一。

2.需要去美国参赛么？A：不需要，我们这个比赛是在北京参加即可。

考点设置在学而思，大钟寺服务中心。

3.这到底什么比赛，什么规模，影响力？A：这个比赛已经有30年历史，是最有影响力的美国物理竞赛，每年有超过10000美国学生参加，今年是第一次允许中国大陆地区考生参加。

对孩子将来申请美国大学，体现自己对物理学科的兴趣和钻研程度，有影响力。

4.考试语言？允许用字典么？A：考试语言全英文。

试卷上都是英文。

答题都是选择题。

允许在考试时使用纸形式的英汉、英英字典。

不允许使用任何电子词典或者其他除了计算器以外的电子设备。

5.考试时间？A：考试时间在2015年4月11日（周六）下午14：00-14：45. 总计45分钟，40道选择题。

请提前半小时到达考场。

6.学而思考点和其他考点有什么区别？A：很多国际学校也有组织集体参加这个比赛，可以选择在学校里面报名参加，也可以选择在学而思报名参加。

7.考试难度如何？初中生能参加么？A：考试分A，B组。

其中A组难度较低，适合高一年级，（或者相应的AP/IB/A-Level课程年级）参加。

B组难度较高，适合高二年级同学和部分优秀的高一年级同学（或者相应的AP/IB/A-Level课程年级）参加。

说白了就是允许低年级报更高难度，但是不能高年级报名低难度。

8.如何评奖？A：学而思考点属于中国华北地区全球15区（包括华北和东北诸多省份：北京、天津、东北三省、河北、山西、山东、内蒙）。

会设立赛区个人奖10名：北方地区前10名，（A、B 组分开）。

全国个人奖：全国前10名（A、B组分开）。

全球个人奖：全球排名前100位（A、B组分开）。

湖南省长沙市长郡双语实验中学八年级物理下学期竞赛预赛试卷(含解析) 新人教版

2015-2016学年湖南省长沙市长郡双语实验中学八年级（下）竞赛预赛物理试卷一．选择题（共66分，每题3分）1．在“达人秀”节目中，演员用冬瓜、土豆做成吹奏乐器，用它们吹奏出来的声音可能具有的相同特征是（）A．音调响度B．音色响度C．音色音调D．音色音调响度2．河中有一漂浮物，甲船在漂浮物上游100米处，乙船在漂浮物下游100米处，若两船同时以相同的速度去打捞，则（）A．甲船先到 B．乙船先到 C．两船同时到达 D．无法判断3．如图所示，是我们看到的筷子斜插入水中的情况，其中正确的是（）A．B．C．D．4．在暗室里用蜡烛做小孔成像实验时，小明在硬纸板的不同位置上戳了圆形、正三角形、正方形和五角形四个小孔，则在墙上可能（）A．出现一个蜡烛火焰的倒像B．出现四个蜡烛火焰的倒像C．出现四个跟小孔形状相同的清晰光斑D．出现四个模糊的光斑5．如图所示，两平面镜夹角为60°，0P为角平分线，某人站在P点，则平面镜M内此人所成的像的个数是（）A．2个B．3个C．5个D．6个6．如图所示，在行驶的列车内的水平桌面上，放置一个气泡水平仪，水平仪的气泡突然向前移动，由此可知列车的运动状态可能发生的变化是（）A．突然启动 B．突然制动C．由运动变为静止D．突然减速7．从井中用绳提上一桶水时，手感到向下的拉力，这拉力的施力物体是（）A．地球 B．水C．水和桶D．绳子8．如图所示，用水平力推静止在水平地面上的大木箱，没有推动．这时，木箱受到的（）A．推力小于摩擦力B．推力和摩擦力大小一定相等C．推力一定小于重力 D．推力和摩擦力方向相同9．如图（a）所示，停在公路旁的公安巡逻车利用超声波可以监测车速：巡逻车上测速仪发出并接收超声波脉冲信号，根据发出和接收到的信号间的时间差，就能测出车速．在图（b）中，P1、P2是测速仪先后发出的超声波信号，n1n2分别是测速仪检测到的P1、P2经反射后的信号．设测速仪匀速扫描，P1与P2之间的时间间隔为0.9秒，超声波在空气中传播的速度为340米/秒，则被测车的车速为（）A．20米/秒B．25米/秒C．30米/秒D．40米/秒10．如图所示，甲容器内装有水，乙试管内也装有水，并通过甲容器密封盖上的孔插入甲容器的水中，且乙试管与密封盖紧密接触．现给甲容器加热，则经过一段时间后（）A．甲容器内的水先沸腾B．乙试管内的水先沸腾C．甲容器、乙试管内的水同时沸腾D．甲容器内的水沸腾，乙试管内的水不会沸腾11．小光在听讲座时，想把银幕上用投影仪投影的彩色幻灯片图象用照相机拍摄下来，由于会场比较暗，他使用了闪光灯，这样拍出来的照片（）A．反而看不清投影到银幕上的图象，倒是把银幕上的一些污渍拍出来了B．色彩鲜艳，比不用闪光灯清楚多了C．色彩被“闪”掉了，拍到的仅有黑色的字和线条D．与不用闪光灯时效果一样，因为拍摄的是银幕上的像，而不是实际的景物12．假设地球表面不存在大气层，那么观察到的日出时刻与实际存在大气层时的情况相比（）A．将提前B．将延后C．不变D．在某些地区将提前，另一些地区将延后13．如图所示，平面镜OM与ON的夹角为θ，一条平行于平面ON的光线经过两个平面镜的多次反射后，能够沿着原来的光路返回，则两平面镜之间的夹角不可能是（）A．20° B．15° C．10° D．5°14．如图（a）所示，平面镜OM与ON夹角为θ，光线AB经过平面镜的两次反射后出射光线为CD．现将平面镜OM与ON同时绕垂直纸面过0点的轴转过一个较小的角度β，而入射光线不变，如图（b）所示．此时经过平面镜的两次反射后的出射光线将（）A．与原先的出射光线CD平行B．与原先的出射光线CD重合C．与原先的出射光线CD之间的夹角为2βD．与原先的出射光线CD之间的夹角为β15．将筷子竖直插入装水的玻璃杯内，从俯视图中的P点沿水平方向看到的应该是如图所示哪个图中的情形（）A． B．C．D．16．在做“凸透镜成像规律”的实验中．当烛焰、透镜及光屏处在图所示位置时，恰能在光屏上得到一个清晰的像．由此判断，他所用凸透镜的焦距（）A．一定小于8cm B．一定在8cm到10cm之间C．一定大于20cm D．一定在10cm到16cm之间17．平面镜水平放置且镜面朝上，在镜面上方竖直放置一凸透镜，在凸透镜左侧主光轴上两倍焦距处有一点光源S，关于点光源在该光具组中成像情况的判断，正确的是（）A．两个实像，两个虚像B．两个实像，一个虚像C．一个实像，两个虚像D．一个实像，三个虚像18．如图所示，F1、F2是凸透镜的焦点，S是放在凸透镜前的点光源，S′是S经凸透镜所成的像．当光源S沿平行主轴的方向向透镜移动时（始终保持u＞f），像S′远离透镜移动的情况是（）A．沿平行主轴方向B．沿O与S′连线方向C．沿F2与S′连线方向D．沿F1与S′连线方向19．现有密度分别为ρ1和ρ2的两种液体，且ρ1＜ρ2．在甲杯中盛满这两种液体，两种液体的质量各占一半；在乙杯中也盛满这两种液体，两种液体的体积各占一半．假设两种液体之间不发生混合现象，甲、乙两个杯子也完全相同．则（）A．甲杯内液体的质量大B．乙杯内液体的质量大C．两杯内液体的质量一样大D．无法确定20．为了铸造金属工件，事先用密度为ρ1的实木材料制成木模，木模的质量为1.8kg．再用密度为ρ2的合金铸造30个这样的工件，这些合金的总质量为648kg，则木模与合金材料密度之比为（）A．1：4 B．1：12 C．1：30 D．1：36021．如图所示，教室里的天花板下面装有多挡位吊扇，当吊扇正常工作时，对于吊扇对天花板的拉力大小与其重力大小的判断，下列说法中正确的是（）A．吊扇在高挡位工作时，拉力等于重力B．吊扇在低挡位工作时，拉力大于重力C．电扇在任意挡位工作时，拉力等于重力D．电扇在任意挡位工作时，拉力小于重力22．如图所示，劲度系数为k1的轻质弹簧A一端固定在地面上并竖直放置，质量为m的物块压在弹簧A上，用一细绳跨过定滑轮，一端与m相连，另一端与劲度系数为k2的轻质弹簧B相连．现用手握住弹簧B的右端使其位于c点时，弹簧B恰好呈水平且没有形变，将弹簧B的右端水平拉到d点时，弹簧A恰好没有形变．已知：K2＜K1，则c、d之间的距离为（）A．B．C．D．二、填空题（共14分，每空2分）23．现有质量均为m的甲、乙两种金属，密度分别为ρ1、ρ2（ρ1＞ρ2），按一定比例混合后，平均密度为，求混合后的最大质量为______（不考虑混合后的体积变化）24．甲、乙两同学想测量一卷筒纸的总长度，考虑到纸筒上绕的纸很长，不可能将纸全部放开拉直了再用尺测量．甲同学的方法是：首先从卷筒纸的标签上了解到，卷筒纸拉开后纸的厚度为d，然后测出卷筒纸内半径为r，外半径为R，则卷筒纸的总长度L为______．乙同学的方法是：首先测出卷筒纸内半径为r，外半径为R，然后拉开部分卷筒纸测出它的长度为L0，此时卷筒纸的外半径由一开始的R减小到R0，则卷筒纸的总长度L为______．25．北方的冬天天气比较寒冷，房间内一般都要安装暖气片供暖．在房间暖气片温度保持不变的情况下，房间内的平衡温度将随外界温度的变化而变化．研究表明，房间内暖气片和房内的温差与房间内外的温差之比保持不变．当外界温度为﹣23℃时，房间内的温度长时间保持13℃不变；当外界温度为﹣18℃时，房间内温度长时间保持16℃不变，则房间内暖气片的温度应为______℃．当房间内温度长时间保持25℃不变时，外界温度为______℃．26．如图所示，两端开口的圆筒内嵌有一凸透镜，透镜主光轴恰好与圆筒中轴线重合．为了测出该透镜的焦距以及透镜在圆筒内的位置，小李同学做如下实验：在圆筒左侧凸透镜的主光轴上放置一点光源S，在圆筒右侧垂直凸透镜的主光轴固定一光屏，点光源S与光屏的距离为L．左右移动圆筒，当圆筒左端面距离点光源S为a时，恰好在光屏上成一个清晰的像；将圆筒向右水平移动距离b，光屏上又出现了一个清晰的像．则凸透镜和圆筒左端面的距离x为______，该透镜的焦距f为______．三、计算题（共20分，每题各10分）27．某船在静水中航速为36km/h，船在河中逆流而上，经过一座桥时，船上的一只木箱不慎被碰落水中（落水后，木箱速度立即与水流速度相同），经过两分钟，船上的人才发现，立即调转船头追赶，在距桥600m处追上木箱，则水的流速是多少？28．目前国际上酒的度数表示法有三种，其中一种称为标准酒度，是指在温度为20℃的条件下，每100毫升酒液中所含酒精量的毫升数．中国也使用这种表示法，它是法国著名化学家盖吕萨克制定的，又称盖吕萨克酒度．蒸馏出来的酒液需要进行勾兑，勾兑一方面为了保障酒的品质，另一方面可以调整酒的度数．若现有60度和30度的酒液若干，酒液中的微量元素忽略不计．求：（1）60度酒液的密度．（2）如果用这两种酒液进行勾兑，获得42度、1000毫升的酒液，那么需要这两种酒液各多少毫升．（已知ρ酒精=0.8×103kg/m3，ρ水=1.0×103kg/m3，不考虑酒液混合后体积减少）2015-2016学年湖南省长沙市长郡双语实验中学八年级（下）竞赛预赛物理试卷参考答案与试题解析一．选择题（共66分，每题3分）1．在“达人秀”节目中，演员用冬瓜、土豆做成吹奏乐器，用它们吹奏出来的声音可能具有的相同特征是（）A．音调响度B．音色响度C．音色音调D．音色音调响度【考点】音调、响度与音色的区分．【分析】声音的特性有三个：音调、响度和音色．音调是指声音的高低，响度是指声音的大小，音色是指声音的感觉特性．【解答】解：不同乐器、不同发声体的材料和结构不同，产生的音色会不同，我们是靠音色来辨别乐器的种类；所以用冬瓜、土豆做成吹奏乐器，用它们吹奏出来的声音的音色一定是不同的，具有的相同特征可能是音调和响度．故选A．【点评】正确区分声音的音调、响度和音色是解决此题的关键．2．河中有一漂浮物，甲船在漂浮物上游100米处，乙船在漂浮物下游100米处，若两船同时以相同的速度去打捞，则（）A．甲船先到 B．乙船先到 C．两船同时到达 D．无法判断【考点】速度公式及其应用；运动和静止的相对性．【分析】此题要注意到河水是流动的，故甲船、乙船、漂浮物都会顺流而下．【解答】解：两船以相同速度去打捞，以两船速度均为v船、河水流速为v水来比较，可知：（1）甲船离漂浮物100米，当甲船顺流而下时，漂浮物也顺流而下，故甲船相对漂浮物的速度为v船，追上漂浮物的时间为（2）乙船逆流而上，故船速实际为v船﹣v水；同时漂浮物要顺流而下，故乙船相对漂浮物的速度为v船，追上漂浮物的时间为由上可知两船是同时到达．故选C．【点评】本题要注意河水是流动的，如果不考虑这点，也能得出两船同时到达的结论，但其考虑过程却是错误的．3．如图所示，是我们看到的筷子斜插入水中的情况，其中正确的是（）A．B．C．D．【考点】光的折射现象及其应用．【分析】我们看到水中的筷子，水的筷子反射的光线，从水中射入空气中时，折射光线向远离法线方向偏折．【解答】解：此时筷子斜插入水中，由于光的折射作用，从上面看筷子水中的部分的位置比实际位置高一些，看起来向上弯折；故选D．【点评】本题主要考查的是学生对光的折射现象的认识，平时多观察、多思考．4．在暗室里用蜡烛做小孔成像实验时，小明在硬纸板的不同位置上戳了圆形、正三角形、正方形和五角形四个小孔，则在墙上可能（）A．出现一个蜡烛火焰的倒像B．出现四个蜡烛火焰的倒像C．出现四个跟小孔形状相同的清晰光斑D．出现四个模糊的光斑【考点】光直线传播的应用．【分析】沿直线传播的光经过小孔后在光屏上会成像，即小孔成像，小孔成像成的是倒立的实像，像的形状与物体的形状相同，与孔的形状无关．【解答】解：小孔成像是由光沿直线传播形成的，小孔成像，成的都是倒立的实像，与小孔的形状无关，像的形状取决于物体的形状，因此在硬纸板的不同位置扎四个不同形状的小孔，则在墙上会出现四个蜡烛火焰的实像．故选B．【点评】本题考查光的直线传播形成的小孔成像现象，此类问题学生往往在孔的形状与成像的形状的关系上出错，要牢记成像的形状与孔的形状无关，完全取决于物体的形状．5．如图所示，两平面镜夹角为60°，0P为角平分线，某人站在P点，则平面镜M内此人所成的像的个数是（）A．2个B．3个C．5个D．6个【考点】平面镜成像的相关作图．【分析】P点在平面镜M中和N中分别成像，像又会分别在M、N中再次成像．【解答】解：P在M、N中分别成像A、A′，同时P在M中所成的像A会在N中再次成像B，P在N中所成的像A′会在M中再次成像B′，A′在M中所成的像C和B′在N中所成的像C′恰好重合，如下图所示：所以在平面镜M内得到的像一共有5个．故选C．【点评】此题中在两个平面镜会成6次像，但是有2个像点会重合，所以最终得到的像的个数是5个．6．如图所示，在行驶的列车内的水平桌面上，放置一个气泡水平仪，水平仪的气泡突然向前移动，由此可知列车的运动状态可能发生的变化是（）A．突然启动 B．突然制动C．由运动变为静止D．突然减速【考点】惯性现象．【分析】物体由于惯性要保持原来的运动状态．质量越大的物体惯性越大，惯性越大越保持原来的运动状态．【解答】解：当列车静止或匀速前进时，液体和列车保持相对静止，气泡在水平仪中间．当列车突然启动或加速时，液体要保持原来的运动状态，向列车后方运动，把气泡挤向列车行驶的方向．故只有A的说法符合实际．故选A．【点评】水平仪中液体的质量远大于气泡的质量，可以理解成液体由于惯性保持原来的运动状态，把气泡挤向液体运动的反方向．7．从井中用绳提上一桶水时，手感到向下的拉力，这拉力的施力物体是（）A．地球 B．水C．水和桶D．绳子【考点】力的概念．【分析】力是物体对物体的作用，产生力的两个物体互为施力物体互为受力物体．【解答】解：用绳子提起水桶，与手接触的是绳子．手对绳子有一个向上的拉力，由于物体间力的作用是相互的，同时绳子也会对手有一个向下的拉力．所以手受到一个向下的力的作用，这个力的施力物体是绳子．故选 D【点评】本题考查了力的概念和力作用的相互性，力的作用方式包括接触和不接触．8．如图所示，用水平力推静止在水平地面上的大木箱，没有推动．这时，木箱受到的（）A．推力小于摩擦力B．推力和摩擦力大小一定相等C．推力一定小于重力 D．推力和摩擦力方向相同【考点】二力平衡条件的应用．【分析】（1）物体静止或做匀速直线运动时，处于平衡状态，所受到的力是一对平衡力；（2）二力平衡的条件是：作用在同一个物体上，大小相等、方向相反、作用在同一直线上．【解答】解：因为用水平力推静止在水平地面上的大木箱，没有推动，所以大木箱，处于静止状态，在水平方向上所受的推力与摩擦力是一对平衡力，所以摩擦力等于推力，并且方向相反．故选B．【点评】此题主要考查了二力平衡条件的应用，解决此题的关键是找出题目中暗含的条件，大木箱处于静止状态即平衡状态，受力平衡．经常地错误认识推不动是由于推力小于摩擦力，没有把握住题目的关键所在．9．如图（a）所示，停在公路旁的公安巡逻车利用超声波可以监测车速：巡逻车上测速仪发出并接收超声波脉冲信号，根据发出和接收到的信号间的时间差，就能测出车速．在图（b）中，P1、P2是测速仪先后发出的超声波信号，n1n2分别是测速仪检测到的P1、P2经反射后的信号．设测速仪匀速扫描，P1与P2之间的时间间隔为0.9秒，超声波在空气中传播的速度为340米/秒，则被测车的车速为（）A．20米/秒B．25米/秒C．30米/秒D．40米/秒【考点】速度公式及其应用；速度的计算．【分析】（1）由题意可知，P1、P2的时间间隔为0.9s，根据图乙所示P1、P2的间隔的刻度值，以及P1、n1和P2、n2之间间隔的刻度值．可以求出P1、n1和P2、n2间的时间，即超声波由发出到接收所需要的时间；从而可以求出超声波前后两次从测速仪汽车所用的时间，结合声速，进而可以求出前后两次汽车到测速仪之间的距离；由于汽车向着测速仪方向运动，所以两者之间的距离在减小．汽车前后两次到测速仪之间的距离之差即为汽车前进的路程．（2）由于两次超声波发出的时间间隔为0.9s．汽车运动的时间为从第一次与超声波相遇开始，到第二次与超声波相遇结束．求出这个时间，就是汽车运动的时间．（3）根据汽车运动的距离和时间，即可求出汽车的运动速度．【解答】解：（1）P1、P2的间隔的刻度值为4.5个格，时间长为0.9s，P1、n1之间间隔的刻度值为1.5个格，所以对应的时间为0.3s；测速仪第一次发出超声波时，经过了0.15s到达了汽车处，而信号从汽车处返回测速仪，也行驶了0.15s的时间；P2、n2之间间隔的刻度值1个格，所以对应的这两点之间对应的时间为0.2s，测速仪第二次发出超声波时，经过了0.1s到达了汽车处，而信号从汽车处返回测速仪，也行驶了0.1s的时间；测速仪第一次发出的信号从汽车处返回到测速仪时，汽车距测速仪：s1=v声t1=340m/s×0.15s=51m；第二次发出的信号从汽车处返回到测速仪时，汽车距测速仪：s2=v声t2=340m/s×0.1s=34m；因此汽车在两次与信号相遇的过程中，行驶了：s′=s1﹣s2=51m﹣34m=17m；（2）这17m共用了：t′=△t﹣+=0.9s﹣0.15s+0.1s=0.85s；（3）所以汽车的车速为：v′===20m/s．故选A．【点评】如何确定汽车运动的时间，是此题的难点．两次信号的时间间隔虽然是0.9秒，但汽车在接收到两次信号时通过的路程所对应的时间不是0.9秒；要从第一次接收到超声波的信号开始计时，到第二次接收到超声波的信号结束，由此来确定其运动时间．10．如图所示，甲容器内装有水，乙试管内也装有水，并通过甲容器密封盖上的孔插入甲容器的水中，且乙试管与密封盖紧密接触．现给甲容器加热，则经过一段时间后（）A．甲容器内的水先沸腾B．乙试管内的水先沸腾C．甲容器、乙试管内的水同时沸腾D．甲容器内的水沸腾，乙试管内的水不会沸腾【考点】沸腾及沸腾条件；沸点及沸点与气压的关系．【分析】液体沸腾有两个必要条件：①达到沸点，②继续吸热，当两个条件同时具备时即可沸腾；液面上的压强越高，液体的沸点越高，反之，气压越低，液体的沸点越低．据此分析判断．【解答】解：甲容器是密封的，给甲容器加热，经过一段时间后，甲容器水面上的气压增大，沸点升高，会高于100℃；乙容器的水从甲容器的水吸收热量，温度升高，当达到水的沸点（100℃）时就会会沸腾，而此时甲容器的水还不能沸腾．再加热甲容器内的水也能沸腾故选B．【点评】本题考查了沸腾及其条件、沸点与气压的关系，综合性强，要求灵活运用所学知识．11．小光在听讲座时，想把银幕上用投影仪投影的彩色幻灯片图象用照相机拍摄下来，由于会场比较暗，他使用了闪光灯，这样拍出来的照片（）A．反而看不清投影到银幕上的图象，倒是把银幕上的一些污渍拍出来了B．色彩鲜艳，比不用闪光灯清楚多了C．色彩被“闪”掉了，拍到的仅有黑色的字和线条D．与不用闪光灯时效果一样，因为拍摄的是银幕上的像，而不是实际的景物【考点】生活中的透镜；漫反射；凸透镜成像的应用．【分析】闪光灯的光比投影仪的光强，白光盖过了投影仪的光．就像白天看星星一样，看不到的．银幕反射彩色的光本来就是漫反射，光很弱．如果用闪光灯，银幕反射白光强度大，只拍出白色银幕或者上面的污点．彩色图片被冲淡，拍不出了．【解答】解：闪光灯的光照射到物体上，可以使物体表面的亮度增大，但闪光灯照射到银幕上以后，只能增加银幕的亮度，而不能增加图象的亮度，相反，图象的亮度和清晰度明显减弱，所以反而看不清银幕上的图象，而银幕上的污渍更加清晰了，银幕上的黑色的字和纸条实际上就是投影片上不透明物体的影子，即黑暗区域．因此不用闪光灯拍摄的效果好．综上所述，只有选项A正确．故选A．【点评】此题不仅仅是考查凸透镜成像的规律，而主要考查光的反射和漫反射，有一定的拔高难度，属于难题．12．假设地球表面不存在大气层，那么观察到的日出时刻与实际存在大气层时的情况相比（）A．将提前B．将延后C．不变D．在某些地区将提前，另一些地区将延后【考点】光的折射现象及其应用．【分析】由光发生折射时的光线偏折情况和光在均匀介质中沿直线传播解答．【解答】解：如果地球表面不存在大气层，太阳光将在真空中沿直线传播，由于地球是圆形的，所以只有太阳升到某一位置时才能观察到；而正因为地球表面上有大气层，阳光射入大气层时会发生折射现象，能够提前观察到；所以如果地球表面不存在大气层，那么观察到的日出时刻与实际存在大气层时的情况相比将延后．故选B．【点评】此题是光折射现象在生活中的实际应用，是应用物理知识解决实际的问题，属于中档题．13．如图所示，平面镜OM与ON的夹角为θ，一条平行于平面ON的光线经过两个平面镜的多次反射后，能够沿着原来的光路返回，则两平面镜之间的夹角不可能是（）A．20° B．15° C．10° D．5°【考点】光的反射定律．【分析】要解决此题首先要明确下面两点：（1）做出光的反射光路图，根据光路图可以确定每次入射时入射角两个平面镜夹角θ的关系．（2）光线原路返回的含义：必须是经过多次反射后，最后的一次入射是垂直于其中的一个平面镜，即入射角等于零．【解答】解：画光的反射光路图如下图所示，由图知：光线第一次反射的入射角为：90°﹣θ；第二次入射时的入射角为：90°﹣2θ；第三次的入射角为：90°﹣3θ；第N次的入射角为：90°﹣Nθ．要想沿原来光路返回需要光线某次反射的入射角为零所以有90°﹣Nθ=0，解得：N=由于N为自然数，所以θ不能等于20°．故选A．【点评】（1）此题考查了光的反射定律并结合了几何方面的知识．（2）明确此题中每一次反射，入射角与两平面镜之间夹角θ的关系是解决此题的一个难点，它利用了几何中三角形的外角等于不相邻的内角和的知识．14．如图（a）所示，平面镜OM与ON夹角为θ，光线AB经过平面镜的两次反射后出射光线为CD．现将平面镜OM与ON同时绕垂直纸面过0点的轴转过一个较小的角度β，而入射光线不变，如图（b）所示．此时经过平面镜的两次反射后的出射光线将（）A．与原先的出射光线CD平行。

2014年美国高中物理碗竞赛题目

2014physics bowl真题中文版1.一个调频广播站用频率为99.99 X 106Hz的电磁波发射信号，以下四个选项中关于该频率书写正确的是（）A.99.99KHzB.99.99MHzC.99.99GHzD.99.99NHzE.99.99THz1.在实验室中，一同学对一个物体的长度进行了6次测量结果如下：5.05cm ,5.06cm,5.07cm,5.06cm,5.07cm,5.09cm.用有效数字的规则下列哪一个选项正确表示了物体的平均长度（）A.5cmB.5.06cmC.5.066 cmD.5.07cmE. 5.1cm2. 一个物体做自由落体运动，在开始下落的头3秒里该物体下落的高度为（）A.10.0mB.15.0mC.30.0mD.45.0mE.90.0m3.如图所示三个质量相等的物体用三条绳子悬挂在教室天花板上保持静止，关于绳子的张力说法正确的是（）A. A的张力最大B.B的张力最大C.C的张力最大ID.绳ABC中张力一样E.绳ABC的张力都为零匚平4. 一个简单的摆由摆球和轻绳组成，忽略空气阻力，可以增加单摆的周期的是（）匚壬A增加摆千^质量B减少摆球质量C增加轻绳的长度D减少轻绳的长度E增加摆动的角度ZES6.MRI是一种医学诊断技术的缩写，下列哪一个是MRI的正确意思（）"（A）N ledical Radio Imaging（B）M inima lly R^dioacti^'e Intel entionN Racier Iiijeotion（I＞）Alapriietic Kadaoisotope Injection（E）la^netic Resoi^ance7.一辆小车从静止开始运动，在3s内速度均匀的加速到7.6m/s,在这段时间里小车运动的位移为（）A.5.7MB.8.1MC.11.4MD.16.1ME.22.8M8. 一个2.5kg的物块被连接到一根理想弹簧末端上做简谐运动，物块的位置可用描述x(t)=0.20cos(8.00t+0.50) 该式里的所有量都为国际单位，下列哪个数值表示物块振动的振（）A.8.00B.4.00C.1.60D.0.50E.0.209.下列哪个物理量不是标量（）A力B能量C质量D速率E压强10.有两个电荷-Q和+Q被固定在x轴上，它们离原点的距离都为a,如图所示。

物理碗大赛physics bowl_1994

PHYSICSBOWL AAPT/MetrologicHigh School Physics ContestPHYSICS BOWL - APRIL 21, 199440 QUESTIONS–45 MINUTESThis contest is sponsored by the American Association of Physics Teachers (AAPT) and Metrologic Instruments to generate interest in physics and to recognize outstanding high school physics students and their teachers.This competition is held in 15 regions each with two divisions. Division I is for students in a first-year physics course; Division II is for students in a second-year physics course. A school's score in a division is the sum of the four highest student scores in that division. To compete in a division, a school must have at least four students participating. A school may compete in either or both divisions, provided that the school has at least four eligible students participating in a division.Winning schools will receive a diode laser from Metrologic Instruments. T-shirts will be given to members of the winning and second-place teams in each region. All participating students will be recognized with a certificate from AAPT and Metrologic Instruments.INSTRUCTIONSIdentification number: Turn to the last page of these instructions and form your ten-digit identification number.Answer sheet: Enter your information and answers on the answer sheet provided. Be sure to use a #2 pencil, fill the area completely, and make no stray marks on the sheet. In the indicated spaces, write in and encode your name (last name first). In the block labeled "IDENTIFICATION NUMBER," write in and encode your ten-digit identification number from the last page of these instructions. In the block labeled "SPECIAL CODES," write in and encode the six-digit number provided by your teacher. You will use only the first 40 answer blocks on the answer sheet.Calculator: A hand-held calculator may be used. However, any memory must be cleared of data and programs. Calculators may not be shared.Formulas and constants: The formulas and constants provided with these instructions may be used.Time limit: 45 minutes.Score: Your score is equal to the number of correct answers (no deduction for incorrect answers). At the regional level, it is possible that schools will have tie scores for first place. In that event, the four top-scoring student entries will be rescored for these schools, from the end of the test forward, until the tie is resolved. Thus, the answers to the last few questions may be important in determining the winner in a region, and you should consider them carefully.Good Luck!YOU MAY TURN TO THE NEXT PAGEPHYSICSBOWL Constants1994 Physics Bowlacceleration due to gravity g= 10 m/s2gravitational constant G= 6.7 x 10-11 N·m2/kg2specific heat of water c w= 1.0 kcal/kg·K = 4.2 x 103 J/kg·Katomic mass unit 1 u= 1.7 x 10-27 kg = 931.5 MeV/c2electron volt 1 eV= 1.6 x 10-19 Jmass of electron m e= 9.1 x 10-31 kgmass of proton m p= 1.7 x 10-27 kgelectronic charge e= 1.6 x 10-19 CCoulomb's constant k= 9.0 x 109 N·m2/C2permittivity constantε0=8.9 x 10-12 C2/N·m2permeability constantµ0= 4π x 10-7 T·m/Aspeed of sound in air (20 o C) v s= 340 m/sspeed of light in vacuum c= 3.0 x 108 m/sPlanck's Constant h= 6.6 x 10-34 J·s = 4.14 x 10-15 eV·sIDENTIFICATION NUMBERUse the instructions below to form your ten-digit identification number___ ___ ___ ___ ___ ___ ___ ___ _0_ _0_Region Div. ZIP codeRegion: If you attend a specialized science and math school or if your school chooses to compete for the extra prizes, enter “20” in the region boxes and proceed to the division instructions. If not, find your state, province, or other geographic region in the following list and enter its two digit code in the region boxes.02Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont03New York, Maritime Provinces, Ontario, Quebec04New Jersey, Pennsylvania05Delaware, District of Columbia, Maryland, North Carolina, Virginia06Alabama, Florida, Georgia, South Carolina, Puerto Rico, Virgin Islands07Kentucky, Ohio, West Virginia08Indiana, Michigan09Illinois, Iowa10Minnesota, North Dakota, South Dakota, Wisconsin11Arkansas, Louisiana, Mississippi, Tennessee12Colorado, Kansas, Missouri, Nebraska, Oklahoma, Wyoming13Arizona, New Mexico, Texas, Utah14California, Hawaii, Nevada, American Samoa, Guam15Alaska, Idaho, Montana, Oregon, Washington, Alberta, British Columbia,Manitoba, Saskatchewan, and others20 Specialized Science and Math SchoolsDivision: Enter a “1” for division I (first-year physics students) or a “2” for division II (second-year physics students) in the Div. box.ZIP code: Enter your school’s five-digit ZIP code in the ZIP code boxes.6. Which of the following statements about the speed of waves on a string are true?I.The speed depends on the tension in the string.II.The speed depends on the frequency.III.The speed depends on the mass per unit length of the string.A. II onlyB. I & II onlyC. I & III onlyD. II & III onlyE. I, II, & III7. A positively charged conductor attracts a second object. Which of the following statements could be true?I. The second object is a conductor with negative net charge.II. The second object is a conductor with zero net charge.III. The second object is an insulator with zero net charge..A. I onlyB. II onlyC. III onlyD. I & II onlyE. I, II & III8. A point charge of +4.0 µC is placed on the negative x-axis0.20 m to the left of the origin, as shown in the accompanying figure.A second point charge q is placed on the positive x-axis 0.30 m tothe right of the origin. The net electric field at the origin is zero.What is q?A. +9.0 µCB. +6.0 µCC. 0D. –6.0 µCE. –9.0 µC9. An atomic mass unit is approximately equal to the mass of a(n):A alpha particle B. electron C. photon D. positron E. proton10. Which device can be used to detect nuclear radiation?A. cyclotronB. photographic filmC. betatronD. synchrotronE. Van de Graaff11. The critical angle of a material is the angle of incidence for which the angle of refraction is:A. 0oB. 30oC. 45oD. 90oE. 180o12. Which of the following could NOT be used to indicate a temperature change? A change in:A. color of a metal rod.B. length of a liquid column.C. pressure of a gas at constant volume.D. electrical resistance.E. mass of one mole of gas at constant pressure.13. The purpose of the December 1993 space shuttle Endeavor mission was to repair the Hubble Space Telescope. The shuttle astronauts corrected the major problem of the telescope when they:A. replaced an improperly ground lens.B. installed corrective optics to compensate for the mis-shaped mirror.C. freed a stuck camera shutter and installed a new roll of film.D. installed a new primary mirror.E. repositioned the transmitting antenna to point towards Earth.14. An arrow is aimed horizontally, directly at the center of a target 20 m away. The arrow hits 0.050 m below the center of the target. Neglecting air resistance, what was the initial speed of the arrow?A. 20 m/sB. 40 m/sC. 100 m/sD. 200 m/sE. 400 m/s15. A car is traveling on a road in hilly terrain, see figure to theright. Assume the car has speed v and the tops and bottoms of thehills have radius of curvature R. The driver of the car is mostlikely to feel weightless:A. at the top of a hill when v>gR.B. at the bottom of a hill when v>gR.C. going down a hill when v=gRD. at the top of a hill when v<gR.E. at the bottom of a hill when v<gR.16. A car of mass m, traveling at speed v, stops in time t when maximum braking force is applied. mass 2m traveling at speed v?A. 1/2tB. tC. 2tD. 2 tE. 417. A cork has weight mg and density 25% of water density. A string is tiedaround the cork and attached to the bottom of a water-filled container. As shownin the accompanying figure, the cork is totally immersed in the water. Expressed interms of the cork weight mg, the tension in the string is:A. 0B. mgC. 2 mgD. 3 mgE. 4 mg0.15 meters. Relative to the object, the image formed by the lens will be:A. real, erect, and smaller.B. real, inverted, and smaller.C. real, inverted, and larger.D. virtual, erect, and larger.E. virtual, inverted, and smaller.19. A string is firmly attached at both ends. When a frequency of60 Hz is applied, the string vibrates in the standing wave patternshown to the right. Assume the tension in the string and its massper unit length do not change. Which of the following frequencies could NOT also produce a standing wave pattern in the string?A. 30 HzB. 40 HzC. 80 HzD. 100 HzE. 180 Hz20. A magnet is dropped through a vertical copper pipe slightly larger than the magnet. Relative to the speed it would fall in air, the magnet in the pipe falls:A. more slowly because it is attracted by the innate magnetic field of the pipe.B. more slowly because the currents induced in the pipe produce an opposing magnetic field.C. at the same rate.D. more quickly because it is attracted by the innate magnetic field of the pipe.E. more quickly because the currents induced in the pipe produce a opposing magnetic field.21. Which of the following statements about solid conductors in electrostatics are true?I.The electric field inside the conductor is always zero.II. The electric potential inside the conductor is always zero.III.Any net charge is on the surface.A. I onlyB. II onlyC. III onlyD. I & III onlyE. II & III only22. A radioactive oxygen 815O nucleus emits a positron and becomes:A. 714NB. 715NC. 815OD. 914FE. 915F23. Albert Einstein won the Nobel Prize in Physics for his work on:A. general relativity.B. high temperature super conductors.C. the photoelectric effect.D. special relativity.E. transistors.24. A sample of radioactive material has an initial activity of 10,000 counts/minute. 30 minutes later, its activity is 2,500 counts/minute. The half-life of the material is:A. 7.5 minutesB. 10 minutesC. 15 minutesD. 20 minutesE. 22 minutes25. One end of a massless rope is attached to a mass mshown in the accompanying figure. Mass m What is m ?A. 3.0 kg B. 2.0 kg C. 1.5 kg 26. As shown in the accompanying figure, a force F of θ. The block of weight mg frictional force acting on the block is:A. µmg to the left.B. µmg to the right.C. µmg –F sin θ to the left.D. µ(mg – F cos θ) to the right.E. µ(mg + F sin θ) to the left.27. A mass m absolute (Kelvin) temperature T gas to 3m A. 2/3 p B. 3/2 p C. 2 p A. K = L > M > N B. K = L = M > N C. K > L = M > N D. N > K > L = M E. N > K = L = Mcurrent I distance a A. µo 2πIa toward the upper left hand corner.B. µo 2πI atoward the lower left hand corner.C. 2 µo 2πIa toward the upper left hand corner.D. 2 µo 2πIa toward the lower left hand corner.E. 0P I30. The conventional current Idistance R from the wire and heading directly toward it, the force on the proton is:A. µo 2πI 2 toward the wire.B. µo 2πI 2L Rupward (in the same direction as I).C. µo 2πI 2LR downward (in the opposite direction to I).D. ev µo 2πIR upward (in the same direction as I).E. ev µo 2πIRdownward (in the opposite direction to I).31. Light of a single frequency falls on a photoelectric material but no electrons are emitted.Electrons may be emitted if the:A. frequency of the light is decreased.B. frequency of the light is increased.C. intensity of the light is decreased.D. intensity of the light is increased.E. velocity of the light is increased.32. In Young’s double slit experiment, second and higher order bright bands can overlap. Which third order band would occur at the same location as a second order band of wavelength 660 nm?A. 1320 nm B. 990 nm C. 495 nm D. 440 nm E. 330 nm 33. An air track car with mass m and velocity v to the right collides elastically with a second air track car with mass 2m and initial velocity zero. What is the velocity of the 2m car after the collision?A. 23v to the rightB. 12v to the right C. 12v to the right D. v to the left E. 13v to the left34. A hypothetical planet orbits a star with mass one-half the mass of our sun. The planet’sorbital radius is the same as the Earth’s. Approximately how many Earth years does it take for the planet to complete one orbit?A.12B. 12C. 1D. 2E. 2I35. A gas can be taken from state a to cprocesses, a →c or a →b →c During the process a →b →cmuch work is done by the system during a →b →c ?A. 5.0 J B. 10.0 J C. 15.0 J D. 20.0 J E. 25.0 J36. What is the current through the 6.0 Ωresistance.A. 0B. 0.40 AC. 0.50 AD. 1.3 AE. 1.5 A37. You are given three 1.0 Ωequivalent resistances CANNOT A. 1/3 ΩB. 2/3 ΩC. 1.0 Ω38. A force F at an angle θ above the horizontal is used to pull a heavy suitcase of weight mg a distance d along a level floor at constant velocity. The coefficient of friction between the floor and the suitcase is µ. The work done by the frictional force is:A. –Fd cos θ B. mgh – Fd cos θ C. –µFd cos θ D. –µmgd E. –µmgd cos θ39. A small object with charge q and weight mg electric field E makes a constant angle θA. positive with magnitudemgE B. positive with magnitude mgEtan θC. negative with magnitudemgE D. negative with magnitude mgE tan θE. negative with magnitude Emgtan θPHYSICSBOWL Answers1994 Physics Bowl1. D21. D2. A22. B3. B23. C4. C24. C5. B25. A6. C26. E7. E27. E8. A28. D9. E29. C10. B30. E11. D31. B12. E32. D13. B33. A14. D34. D15. A35. C16. D36. A17. D37. C18. C38. A19. A39. B20. B40. E。

的物理碗作为名副其实的竞赛性价比之王每年有超过名中国学生参加

的物理碗作为名副其实的竞赛性价比之王每年有超过名中国学生参加留学界有个传言，“学习物理碗=拿下AP物理4门”！“PhysicsBowl（物理碗）”是指美国高中物理思维挑战，由权威的美国物理教师协会（AAPT）主办，11个国家超过500所学校上万名选手参加，全球统一成绩排名，优胜者将获邀请参加全球顶级科学活动与科研项目。

在GPA、标化成绩、托福成绩相差不大的基础上，多有一个物理碗考试成绩更助于学生申请大学。

全球排名TOP100的学生超过37%被全美TOP30大学录取，达到前30%也是申请美国高校的重要加分项。

物理碗适合有目标，想要为大学申请助力的学霸党，需要竞赛进一步提升学术实力和个人素质；不适合无目标学校，只想修完课程就好的同学。

对于准备申请物理学、机械工程、材料学等专业的同学来说，参加物理碗拿到好成绩能够提升录取竞争力，为心仪学校申请增加有效法码。

且物理碗的获奖率对同学们来说十分“友好”，只要获得全国前35%的名次，就能获得奖项！物理碗多数题目都很简单，但越往后题目越难，所以最大的挑战就是时间！物理碗分为两个不同难度的Division：比较简单的 Division 1(考题中1-40道)，适合高一学生选择；而比较困难的Division 2(考题中11-50道)，适合高二，高三学生选择。

物理碗可以说已经成了申请世界名校，尤其是物理学专业的“标配”竞赛了。

尽管它并不算难度最TOP的竞赛，但具有较高的知名度及含金量，使得它在升学上的作用不容小觑，那不同体系的同学该怎么做好物理碗备考呢？10年级同学从11月份或者寒假1月份开始准备，需要在两个月里尽可能多的学习AP物理1和2的基础知识，而11年级的同学如果参加Division 1会非常有优势，一般刷历年真题就可以轻松在Division 1里取得25分左右的成绩。

但如果想拿到更高的分数，那就需要提前学完近代物理、天文学相关章节，补齐AP物理里没有涉及的知识。

深圳东方英文书院物理八年级下册期末试卷含答案

深圳东方英文书院物理八年级下册期末试卷含答案一、选择题1．下面是对日常生活中一些数据的估计，其中最接近实际的是（）A．一名中学生所受的重力约为120N B．初中物理教科书的质量约0.12kgC．人的正常步行速度约12m/s D．雪峰山山顶的大气压大约是1.2×105Pa 2．如图所示，人沿水平方向推装满沙子的车，但没有推动。

下列说法正确的是（）A．人对车的作用力小于车对人的作用力B．人对车的推力小于地面对车的摩擦力C．人对车的推力与车对人的推力是一对平衡力D．沙子受到的重力与车对沙子的支持力是一对平衡力3．体育运动中涉及到了许多物理知识，下列说法不正确的是（）A．篮球投篮出手后如果外力全部消失，将会做匀速直线运动B．踢出去的足球最终会停下来，是因为受到摩擦阻力的作用C．多次用力垫起排球，手臂感到疼是因为力的作用是相互的D．射箭时，箭离开弓弦后由于受到惯性作用仍继续向前飞行4．“车辆转弯，请坐稳扶好！”公交车广告提醒乘客注意安全。

如图所示，公交车扶手上装有拉环，避免乘客受到伤害。

拉环在设计上注重人性化，拉环上有凹凸纹且拉环做得比较厚大。

下列说法正确的是（）A．坐稳扶好是为了防止惯性带来的伤害B．拉环上的凹凸纹是为了减小摩擦C．拉环做得比较厚大是通过增大受力面积来增大压强D．公交车向右急转弯时乘客将会向右倾倒5．以下实例中，利用连通器原理工作的是（）A．医用注射器B．液体密度计C．锅炉水位计D．家用吸尘器6．如图所示，为一可绕O点转动的杠杆，在A端通过绳作用一竖直向下的拉力F使杠杆平衡，此时AB部分水平，保持重物静止不动，而使绳绕A点从图所示的位置沿图中的虚线CD转动，则（）A．逆时针转，F先变小后变大B．顺时针转，F先变小后变大C．顺时针转，F先变大后变小D．逆时针转，F先变大后变小7．两个完全相同的装有水的圆柱形容器甲、乙放置在水平桌面上，将体积相等的不同小球A 、B 分别轻放入容器甲、乙中，如图所示，小球A 漂浮，小球B 悬浮，水未溢出。

深圳东方英文书院物理八年级下册期末试卷含答案

深圳东方英文书院物理八年级下册期末试卷含答案一、选择题1．下列估测值最接近实际的是（）A．一张课桌的高度约为2m B．洗澡水的温度约为70℃C．一名初中学生的重力约为50N D．一个鸡蛋的质量约为50g2．关于力的三要素，下面说法中正确的是（）A．只要两个力作用在同一个点，产生的效果就相同B．只要力的三要素中两个相同，那么这两个力作用效果就相同C．只要两个力的大小、方向相同，且作用在同一个物体上，则产生的效果就相同D．如果两个大小相等、方向相同的力作用在物体上的同一点，产生的效果就相同3．如图所示小球从A点静止释放，当它运动到右侧最高点B点时绳子突然断掉，并且不再受任何外力时，小球将（）A．小球将在B点保持静止B．小球将沿C轨迹斜向上运动C．小球将沿D轨迹水平向右运动D．小球将沿E轨迹竖直向下落4．同学们，植树的场景还记得吗？下列现象与物理知识联系错误的是（）A．“移栽树苗”手紧握树苗干——增大压力，增大摩擦B．“水桶提水”手握提手粗大部位——增大受力面积，增大压强C．“铲子撒土”——利用了惯性D．标有“植树信息”的木签插入土中——减小受力面积，增大压强5．某同学将一支自制的简易密度计放人盛有不同液体的两个烧杯中，静止后的情形如图所示，两液面相平｡下列判断正确的是A．密度计在甲液体中受到的浮力比在乙液体中受到的浮力小B．甲液体对容器底部的压强比乙液体对容器底部的压强小C．密度计越靠上的刻度，对应的密度值越大D．甲液体的密度比乙液体的密度大6．我国无产阶级革命家、党和国家的卓越领导人陶铸说过“劳动是一切知识的源泉”，撬棍是人们在劳动中应用物理杠杆原理的工具。

如图所示小方同学利用撬棍撬动大石头，撬棍上O 点为杠杆的支点，下列分析正确的是（）A ．此时撬棍为等臂杠杆B ．力F 的作用点远离O 点更费力C ．应用此撬棍的主要目的是省力D ．应用此撬棍的主要目的是省距离7．用刻度尺、塑料碗、大烧杯(底面积为S )等器材测量金属球的体积和质量，他先在烧杯内放入适量水，再将塑料碗轻轻放入水中，如图甲所示，测出此时烧杯内水的深度为h 1；将金属球放在塑料碗中，放入球后的状态如图乙所示，测出此时烧杯内水的深度为h 2；将塑料碗中的金属球轻放入烧杯中，如图丙所示，测出此时烧杯内水的深度为h 3．下列有关叙述中，正确的是A ．金属球的体积是(h 3一h 2)SB ．丙中金属球受到水的浮力是ρ水g (h 2一h l )SC ．金属球的质量是ρ水(h 2一h 1)SD．金属球的密度是8．如图所示，质量为m 的小球从静止下落，落在与A 点等高处、竖直放置静止的轻弹簧上，到达与B 点等高处时小球重力与弹簧的弹力大小相等，图中与C 点等高处是小球到达的最低点（不计空气阻力）。

2024届吉林省吉林大学附中高三第二次模拟理综物理高频考点试卷(基础必刷)

2024届吉林省吉林大学附中高三第二次模拟理综物理高频考点试卷（基础必刷）一、单项选择题（本题包含8小题，每小题4分，共32分。

在每小题给出的四个选项中，只有一项是符合题目要求的）(共8题)第(1)题图为氢原子能级的示意图，现有大量的氢原子处于以n=4的激发态，当向低能级跃迁时辐射出若干不同频率的光．关于这些光下列说法正确的是A．最容易表现出衍射现象的光是由，n=4能级跃迁到n=1能级产生的B．频率最小的光是由n=2能级跃迁到n=1能级产生的C．这些氢原子总共可辐射出3种不同频率的光D．用n=2能级跃迁到n=1能级辐射出的光照射逸出功为6.34eV的金属铂能发生光电效应第(2)题在重核裂变反应方程中（），括号中的产物是（）A．粒子B．粒子C．光子D．中子第(3)题某超小型风力发电机与理想变压器的原线圈连接，变压器的副线圈接内阻为的电动机。

某日该地区的风速是5m/s，风吹到叶片的有效面积为，此时变压器原线圈两端的电压为30V，电动机刚好正常工作。

已知空气的密度为，假如该风力发电机能将通过扇叶有效面积内空气动能的40%转化为电能，变压器原、副线圈匝数比为，发电机和变压器的线圈电阻忽略不计。

下列说法正确的是（）A．每秒冲击发电机叶片的空气动能为120JB．通过变压器原线圈的电流为4AC．通过变压器副线圈的电流为8AD．电动机消耗的电功率为720W第(4)题用锤头敲玻璃，玻璃被打碎，而锤头未碎，对于这一现象，下列说法正确的是（）A．锤头对玻璃的作用力大于玻璃对锤头的作用力，所以玻璃才碎裂B．玻璃对锤头的作用力大于锤头对玻璃的作用力，只是由于锤头比玻璃能够承受更大的力才没有碎裂C．锤头和玻璃之间的作用力是等大的，只是由于锤头比玻璃能够承受更大的力才没有碎裂D．因为不清楚锤头和玻璃的其他受力情况，所以无法判断它们之间的相互作用力的大小关系第(5)题对于体育比赛的论述，下列说法正确的是（）A．运动员跑完800m比赛，指的是路程大小为800mB．运动员铅球成绩为4.50m，指的是位移大小为4.50mC．某场篮球比赛打了两个加时赛，共需10min，指的是时刻D．足球比赛挑边时，上抛的硬币落回地面猜测正反面，该硬币可以看作质点第(6)题质谱仪是分析同位素的重要的仪器，在物理研究中起非常重要的作用。

深圳东方英文书院物理八年级下册期末试卷含答案

深圳东方英文书院物理八年级下册期末试卷含答案一、选择题1．下列数据最接近实际的是（）A．八年级物理书的重力约为8NB．一名普通中学生双脚站立时对地面的压强约为1×104PaC．一台起重机的机械效率一般为90%D．优秀运动员短时间运动的功率约为100W2．关于“立定跳远”，以下说法不正确的是（）A．立定跳远前，静止站在地面上的人所受的重力和支持力是一对平衡力B．立定跳远时，向后蹬地瞬间，人受到向前的力，说明物体间力的作用是相互的C．立定跳远中，人离地后继续向前运动，因为受到惯性力的作用D．从起跳，腾空到落地的过程中，体现了力可以改变物体的运动状态3．如图摆球从A点静止释放，经过最低点B点，摆向另一侧的最高点C点，在此过程中，下列说法中正确的是（）A．小球到达B点的瞬间，若剪断悬线，小球将沿水平方向做匀速直线运动B．小球到达B点的瞬间，若受到的力全部消失，小球将保持静止状态C．小球到达C点的瞬间，若受到的力全部消失，小球将保持静止状态D．小球到达C点的瞬间，若受到的力全部消失，小球将做匀速直线运动4．生活中处处有物理，下列与压强知识有关的说法中，正确的是（）A．书包背带做得宽而平，是为了增加受力面积从而增大压强B．能用吸管将杯中饮料吸进嘴里，是利用了大气压强C．大气压强是随着海拔的升高而增大D．在气体和液体中，流速越大的位置，压强越大5．某同学将一支自制的简易密度计放人盛有不同液体的两个烧杯中，静止后的情形如图所示，两液面相平｡下列判断正确的是A．密度计在甲液体中受到的浮力比在乙液体中受到的浮力小B．甲液体对容器底部的压强比乙液体对容器底部的压强小C．密度计越靠上的刻度，对应的密度值越大D．甲液体的密度比乙液体的密度大6．如图所示的生活用具中，使用时属于等臂杠杆的是（）A．筷子B．托盘天平C．核桃夹D．瓶起子7．如图所示，三个相同的容器内水面高度相同，甲容器内只有水，乙容器内有木块漂浮在水面上，丙容器中悬浮着一个小球，则下列四种说法正确的是（）A．三个容器对水平桌面的压力相等B．三个容器中，丙容器对水平桌面的压力最大C．如果向乙容器中加入盐水，木块受到的浮力变大D．如果向丙容器中加入酒精，小球受到的浮力不变8．图甲所示，超超在平地上用水平向右的力推木箱，推力随时间变化的图像如图乙所示，木箱速度随时间变化的图像如图丙所示，以下说法正确的是（）A．0~3s内推力小于摩擦力B．3s~6s内木箱处于平衡状态C．6s~9s内木箱所受摩擦力大小为3ND．9s~12s内推力做功的功率大小为6W二、填空题9．图示数为___________N，图示数为___________g。