题库网 (tiku.one)

 找回密码
 立即注册

 

      

上传图片附件

未使用图片

小贴士: 允许的图片文件格式为: gif, jpg, jpeg, png, webp,上传完成后会在上方生成预览,用鼠标连续双击缩略图,或拖动缩略图,该图片就被绑定至本题,显示在题目下方

本次作答已使用

小贴士: 此栏目显示的是当前作答使用的所有图片,绑定到某一题目的图片同时会显示在该题目下方; 删除使用的图片会将其转移到<未使用图片>类别


习题练习:2011 美国F=ma物理竞赛 F=ma physics competition



 作者: admin   总分: 25分  得分: _____________

答题人: 匿名未登录  开始时间: 23年12月09日 21:14  切换到: 整卷模式

标记此题
1#
 
单选题 ( 1.0 分) (组内1/1) 切至整卷模式 搜藏此题  
第 1 题组 (共 1 题 1 分)
  A cyclist travels at d /oykczt282qso: 8yq65 qie la constant speed of $22.0 \mathrm{~km} / \mathrm{hr}$ except for a 20 minute stop. The cyclists average speed was $17.5 \mathrm{~km} / \mathrm{hr}$. How far did the cyclist travel?

参考答案:    

标记此题
2#
 
单选题 ( 1.0 分) (组内1/3) 切至整卷模式 搜藏此题  
第 2 题组 (共 3 题 3 分) 当前第1/3题
题组内容描述:
Questions 1 to 3 refer to the three graphs below which show velocity of three objects as a function of time. Each object is moving only in one dimension.
  Rank the magnitudes of the a rqa d:+g). v8cvx )xn6paqs.overage acceleration during the ten second interval.

参考答案:    

标记此题
3#
 
单选题 ( 1.0 分) (组内2/3) 切至整卷模式 搜藏此题  
第 2 题组 (共 3 题 3 分) 当前第2/3题
题组内容描述:
Questions 1 to 3 refer to the three graphs below which show velocity of three objects as a function of time. Each object is moving only in one dimension.
  Rank the magnitudes of the maximum velocity achieved duri ;ezv;i mlv(lw.0f4qdng the ten second interva;e;md0zwvl(vl .q4fi l.

参考答案:    

标记此题
4#
 
单选题 ( 1.0 分) (组内3/3) 切至整卷模式 搜藏此题  
第 2 题组 (共 3 题 3 分) 当前第3/3题
题组内容描述:
Questions 1 to 3 refer to the three graphs below which show velocity of three objects as a function of time. Each object is moving only in one dimension.
  Rank the magnitudes of thekjb6u60xk gl db8g6h, distance traveled during the ten second interval.

参考答案:    

标记此题
5#
 
单选题 ( 1.0 分) (组内1/11) 切至整卷模式 搜藏此题  
第 3 题组 (共 11 题 11 分)
  A crude approximation is thsp am5xz3 *mzgcgv0)* at the Earth travels in a circular orbit about the Sun at constant speed, at a d5 m0m* xag3szvpg) z*cistance of $150,000,000 \mathrm{~km}$ from the Sun. Which of the following is the closest for the acceleration of the Earth in this orbit?

参考答案:    

标记此题
6#
 
单选题 ( 1.0 分) (组内2/11) 切至整卷模式 搜藏此题  
  A child is sliding out of control with velocityb uu+ba3djhk- v.1 , l9ak)fba $v_{\mathrm{c}}$ across a frozen lake. He runs head-on into another child, initially at rest, with 3 times the mass of the first child, who holds on so that the two now slide together. What is the velocity of the couple after the collision?

参考答案:    

标记此题
7#
 
单选题 ( 1.0 分) (组内3/11) 切至整卷模式 搜藏此题  
  An ice skater can rotate about a vertical axis with an angular.c ;es+s2u 4cgcvy7gq velocity $\omega_{0}$ by holding her arms straight out. She can then pull in her arms close to her body so that her angular velocity changes to $2 \omega_{0}$, without the application of any external torque. What is the ratio of her final rotational kinetic energy to her initial rotational kinetic energy?

参考答案:    

标记此题
8#
 
单选题 ( 1.0 分) (组内4/11) 切至整卷模式 搜藏此题  
  When a block of wood with a weight of1 +j2 kas:) ; lv1kxxhtcfgf4s $30 \mathrm{~N}$ is completely submerged under water the buoyant force on the block of wood from the water is $50 \mathrm{~N}$. When the block is released it floats at the
surface. What fraction of the block will then be visible above the surface of the water when the block is floating?

参考答案:    

标记此题
9#
 
单选题 ( 1.0 分) (组内5/11) 切至整卷模式 搜藏此题  
  A spring has an equilibrium length of 2.0 meters and a spring constant of 10 nenkia..2;nh7 7oxsuwu wtons/meter. Alice is pulling on one end of the spring with a force of 3.0 newtons. Bob is pulling on the opposite end of the spring with a force of 3.0 ne2. ux nsn 7;7ikhoaw.uwtons, in the opposite direction. What is the resulting length of the spring?

参考答案:    

标记此题
10#
 
单选题 ( 1.0 分) (组内6/11) 切至整卷模式 搜藏此题  
  Which of the following changes will result in an increas3h/ ym id1hdx,e in the period of a simple y,1dx/h3d h mipendulum?

参考答案:    

标记此题
11#
 
单选题 ( 1.0 分) (组内7/11) 切至整卷模式 搜藏此题  
  A large metal cylindrical cup floats in a rectangular tub half-filled c 2q6pbi1k;zj+ l7is.zskfk qm*v z3: with water. The tap is placed over the cup and turned on, releasing water at a constant rate. Eventually the cup sinks to the6vk p2.3zml;:qb kjc1ksiizf+ zs*7q bottom and is completely submerged. Which of the following five graphs could represent the water level in the sink as a function of time?


参考答案:    

标记此题
12#
 
单选题 ( 1.0 分) (组内8/11) 切至整卷模式 搜藏此题  
  You are given a large collection of identical heavy balls and l q4bn (,7qk 89vlfi0shdb7 xr+z ji-ahightweight rods. When two balls are placed at the ends of on,bba9+frivqn0sk-7 z4d8h lhx i7 (jqe rod and interact through their mutual gravitational attraction (as is shown on the left), the compressive force in the rod is $F$. Next, three balls and three rods are placed at the vertexes and edges of an equilateral triangle (as is shown on the right). What is the compressive force in each rod in the latter case?




参考答案:    

标记此题
13#
 
单选题 ( 1.0 分) (组内9/11) 切至整卷模式 搜藏此题  
  The apparatus in the diagram consists of a solid cni altsv7(jiub64( p v)r z7z +o:8accylinder of radius $1 \mathrm{~cm}$ attached at the center to two disks of radius $2 \mathrm{~cm}$. It is placed on a surface where it can roll, but will not slip. A thread is wound around the central cylinder. When the thread is pulled at the angle $\theta=90^{\circ}$ to the horizontal (directly up), the apparatus rolls to the right. Which below is the largest value of $\theta$ for which it will not roll to the right when pulling on the thread?




参考答案:    

标记此题
14#
 
单选题 ( 1.0 分) (组内10/11) 切至整卷模式 搜藏此题  
  You have 5 different strings with mtxgrh/ h3tiuuvos),0-,di/ w1 :nbzy8/ khkweights tied at various point, all hanging from the ceiling, and reaching down to the floor. The string is released at the top, allowinwk)1rd:zsmtnouy,vxt-u //g h8b0/h, 3 ihikg the weights to fall. Which one will create a regular, uniform beating sound as the weights hit the floor?


参考答案:    

标记此题
15#
 
单选题 ( 1.0 分) (组内11/11) 切至整卷模式 搜藏此题  
  A vertical mass-spring oscl(gjj bm*w+*(v j kmv)illator is displaced $2.0 \mathrm{~cm}$ from equilibrium. The $100 \mathrm{~g}$ mass passes through the equilibrium point with a speed of $0.75 \mathrm{~m} / \mathrm{s}$. What is the spring constant of the spring?

参考答案:    

标记此题
16#
 
单选题 ( 1.0 分) (组内1/2) 切至整卷模式 搜藏此题  
第 4 题组 (共 2 题 2 分)
题组内容描述:
Questions 1 and 2 refer to the information and diagram below.Jonathan is using a rope to lift a box with Becky in it; the box is hanging off the side of a bridge, Jonathan is on top. A rope is hooked up from the box and passes a fixed railing; Jonathan holds the box up by pressing the rope against the railing with a massless, frictionless physics textbook. The static friction coefficient between the rope and railing is $\mu_{s}$; the kinetic friction coefficient between the rope and railing is $\mu_{k}<\mu_{s}$; the mass of the box and Becky combined is $M$; and the initial height of the bottom of the box above the ground is $h$. Assume a massless rope.
  What magnitude force does Jonathan need to exert on the physics boo67.:t acce8kw +kk xv mkza53sk to keep the rope from slippk:tak+3 c6e c75zm.xs kkva8w ing?

参考答案:    

标记此题
17#
 
单选题 ( 1.0 分) (组内2/2) 切至整卷模式 搜藏此题  
  Jonathan applies a normal force that is just enough to keep the rope from slipmz7j ; :ps/gpmt 3r/3es eeb1gping. Becky makes a small jump, barely leaving contact with the floor of the box. Upon landing e31s ms p/ zemgr;p 73j:gb/teon the box, the force of the impact causes the rope to start slipping from Jonathans hand. At what speed does the box smash into the ground? Assume Jonathans normal force does not change.

参考答案:    

标记此题
18#
 
单选题 ( 1.0 分) (组内1/1) 切至整卷模式 搜藏此题  
第 5 题组 (共 1 题 1 分)
  A block of mass $m=3.0 \mathrm{~kg}$ slides down one ramp, and then up a second ramp. The coefficient of kinetic friction between the block and each ramp is $\mu_{\mathrm{k}}=0.40$. The block begins at a height $\mathrm{h}_{1}=1.0 \mathrm{~m}$ above the horizontal. Both ramps are at a $30^{\circ}$ incline above the horizontal. To what height above the horizontal does the block rise on the second ramp?

参考答案:    

标记此题
19#
 
单选题 ( 1.0 分) (组内1/2) 切至整卷模式 搜藏此题  
第 6 题组 (共 2 题 2 分)
题组内容描述:
Questions 1 and 2 refer to the following information
A particle of mass $2.00 \mathrm{~kg}$ moves under a force given by
$$\vec{F}=-(8.00 \mathrm{~N} / \mathrm{m})(x \hat{i}+y \hat{j})$$
where $\hat{i}$ and $\hat{j}$ are unit vectors in the $x$ and $y$ directions. The partricle is placed at the origin with an initial velocity of $\vec{v}=(3.00 \mathrm{~m} / \mathrm{s}) \hat{i}+(4.00 \mathrm{~m} / \mathrm{s}) \hat{j}$.
  After how much time will the pgorgohi4y*va9h r119 article first return to the origin?

参考答案:    

标记此题
20#
 
单选题 ( 1.0 分) (组内2/2) 切至整卷模式 搜藏此题  
  What is the maximum distance between the partiq*dux+y)vq/ / ;3ziwc rc8 pelcle and the origin?

参考答案:    

标记此题
21#
 
单选题 ( 1.0 分) (组内1/5) 切至整卷模式 搜藏此题  
第 7 题组 (共 5 题 5 分)
  An engineer is given a wvcuq;xi-4d4gvjv, f5,vho0 fixed volume $V_{m}$ of metal with which to construct a spherical pressure vessel. Interestingly, assuming the vessel has thin walls and is always pressurized to near its bursting point, the amount of gas the vessel can contain, $n$ (measured in moles), does not depend on the radius $r$ of the vessel; instead it depends only on $V_{m}$ (measured in $\mathrm{m}^{3}$ ), the temperature $T$ (measured in $\mathrm{K}$ ), the ideal gas constant $R$ (measured in $\mathrm{J} /(\mathrm{K} \cdot \mathrm{mol})$ ), and the
tensile strength of the metal $\sigma$ (measured in $\mathrm{N} / \mathrm{m}^{2}$ ). Which of the following gives $n$ in terms of these parameters?

参考答案:    

标记此题
22#
 
单选题 ( 1.0 分) (组内2/5) 切至整卷模式 搜藏此题  
  This graph depicts the torque output of a hypothetical gasolh/mpfub2olnj g)99;n ine engine as a function of rotation frequency. The engine is incapable of running outsig9j o9bm/f2n)phlu; nde of the graphed range.


At what engine RPM (revolutions per minute) does the engine produce maximum power?

参考答案:    

标记此题
23#
 
单选题 ( 1.0 分) (组内3/5) 切至整卷模式 搜藏此题  
  A particle is launched from the surface joa,0.sa:os ) qeiq ags-:w -uof a uniform, stationary spherical planet at an angle to the vertical. The particle travels in the absence of air resistance and eventually falls back onto the planet. Spaceman Fred describes the path of the particle as a parabola using the laws of projectile motion sai eo:uw q)aag,o0.ssq-:j -. Spacewoman Kate recalls from Keplers laws that every bound orbit
around a point mass is an ellipse (or circle), and that the gravitation due to a uniform sphere is identical to that of a point mass. Which of the following best explains the discrepancy?

参考答案:    

标记此题
24#
 
单选题 ( 1.0 分) (组内4/5) 切至整卷模式 搜藏此题  
  A turntable is supported on a Teflon ring of inner radiqj 3j8ov(zu6 gus $R$ and outer radius $R+\sigma(\sigma << R)$, as shown in the diagram. To rotate the turntable at a constant rate, power must be supplied to overcome friction. The manufacturer of the turntable wishes to reduce the power required without changing the rotation rate, the weight of the turntable, or the coefficient of friction of the Teflon surface. Engineers propose two solutions: increasing the width of the bearing (increasing $\sigma$ ), or increasing the radius (increasing $R$ ). What are the effects of these proposed changes?



参考答案:    

标记此题
25#
 
单选题 ( 1.0 分) (组内5/5) 切至整卷模式 搜藏此题  
  A hollow cylinder with a very thin wall (like a toilet paper tubero9uy ,gj7rm3g88 atz upf27i o1f o(p) and a block are placed at rest at the top of a plangpy1uz jo72gtr( ma,98 fopuo 8i7fr 3e with inclination $\theta$ above the horizontal. The cylinder rolls down the plane without slipping and the block slides down the plane; it is found that both objects reach the bottom of the plane simultaneously. What is the coefficient of kinetic friction between the block and the plane?

参考答案:    

  • 答题人:
  • 总分:25分 及格:15分 时间:不限时
    未答题: 已答题:0 答错题:
    当前第 题,此次习题练习共有 25 道题
    本系统支持习题练习,作业与考试三大模式,作业考试自动评分,成绩排序一键导出,可设定动态变量同一试卷千人千题
    如果您对本系统感兴趣,想加入我们或者想进行任何形式的合作,请加微信 skysky1258

    浏览记录|使用帮助|手机版|切到手机版|题库网 (https://tiku.one)

    GMT+8, 2024-10-5 02:25 , Processed in 0.202018 second(s), 90 queries , Redis On.