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习题练习:Physics Unit2: Kinematics One Dimensional Motion



 作者: admin   总分: 149分  得分: _____________

答题人: 匿名未登录  开始时间: 22年07月19日 23:10  切换到: 整卷模式

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1#
 
单选题 ( 1.0 分) (组内1/93) 切至整卷模式 搜藏此题  
第 1 题组 (共 93 题 103 分)
  Suppose that an object travels from one point in space to another. Make a compa4e .qef9i fz4aaf2wb7rison between t24b q4 eefw7zaif9a.fhe displacement and the distance traveled.

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2#
 
单选题 ( 1.0 分) (组内2/93) 切至整卷模式 搜藏此题  
  When is the average velocity of an object equal to th deh9,el y).uae instantaneous velocity?

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3#
 
单选题 ( 1.0 分) (组内3/93) 切至整卷模式 搜藏此题  
  A new car manufacturer advertises that thej 7.umejuhkr-.ps s)+ir car can go "from zero to sixty in 8 s". eu7ps).us-jk .hm+ jrThis is a description of

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4#
 
单选题 ( 1.0 分) (组内4/93) 切至整卷模式 搜藏此题  
  An object moving in the +x ky+5 idr.*hfgh 2c (y(w h9ikeaxis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

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5#
 
单选题 ( 1.0 分) (组内5/93) 切至整卷模式 搜藏此题  
  Suppose that a car traw*xhy,a kph.9. ca3y 5kgay,1nj *apzveling to the East (+x direction) begins to slow down as it akpawg ,kz*ya,yc1 5hjyp.xnha 3.9 *approaches a traffic light. Make a statement concerning its acceleration.

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6#
 
单选题 ( 1.0 分) (组内6/93) 切至整卷模式 搜藏此题  
  Suppose that a car traveling to the West (-x dir+vcw0 9urmip .k*ki71mk x;ax ection) begins to slow down as it approaches a traffic light. Make a statement concerning 9vmikkr*0 w;i+amxxp.kcu 17 its acceleration.

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7#
 
单选题 ( 1.0 分) (组内7/93) 切至整卷模式 搜藏此题  
  Suppose that an object is moving with a constant velo/ws4ys -juib1k uidwat j5/9 7city. Make a statement concerning its accelerss 7wkbiud j94/y-wu jai/5t1ation.

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8#
 
单选题 ( 1.0 分) (组内8/93) 切至整卷模式 搜藏此题  
  If the velocity of an object is zero, does it mean that the acceleratio7)wvymbc/c1wy:2m/q;) )n c f*7dmysrdi awqn is zero? Support your answer with an wqqdv wnybr /mis2cf)a7wmc7/:ymc; ) 1 y)*dexample.

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9#
 
单选题 ( 1.0 分) (组内9/93) 切至整卷模式 搜藏此题  
  Can an object's velocity change direction when its acceleration isp sw 4.62qp. b 8nq/3cxn ;hnk68e1jjlaplrfe constant? Supportplb/3 jr2 n6n k 4nx1c8wl pjqqa86efp;hes.. your answer with an example.

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10#
 
单选题 ( 1.0 分) (组内10/93) 切至整卷模式 搜藏此题  
  Suppose that an object is moving with consta2lg;j ,tb q +7pto 1m)pkggg/bnt acceleration. Make a statement concerning its motion with2jb g,m;l o7g b)tpkq+t1g /pg respect to time.

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11#
 
单选题 ( 1.0 分) (组内11/93) 切至整卷模式 搜藏此题  
  Can an object have increasing speed while its acceleration isn:atvo.ja*rfc ufc8 ; r1 9/wb decreasing? Support your answer with an example.fj9af; u1w.nc vr:t obar8*c /

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12#
 
单选题 ( 1.0 分) (组内12/93) 切至整卷模式 搜藏此题  
  Suppose a can, after an initial kick, moves up along a smooth hx3 qeu g7zmf 409hk-heill of ice. Make a statement concerningzh-mk e7uq3h xef9 40g its acceleration.

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13#
 
单选题 ( 1.0 分) (组内13/93) 切至整卷模式 搜藏此题  
  Under what condition is average velocity equif- m6ai3nb 5j t7 v2g uqhea:09+gcbjal to the average of the object's initial and final velg7 tgbu25 n0ih6:+3avajm-f bj9eic qocity?

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14#
 
单选题 ( 1.0 分) (组内14/93) 切至整卷模式 搜藏此题  
  Objects A and B both s,rgcq:i3z ey-j z+8qy+x w yf(tart at rest. They both accelerate at the same rate. However, object A ac3gz ew zqq:-+xy+(,y8fyr ic jcelerates for twice the time as object B. What is the final speed of object A compared to that of object B?

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15#
 
单选题 ( 1.0 分) (组内15/93) 切至整卷模式 搜藏此题  
  Objects A and B both start from rest. 1r.m3mnp/ /5n0g bnxreo7s2hdm /oz h They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared t30o /bmd gnh 7.rm/m xpshe1n2r5zn/o o that of object B?

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16#
 
单选题 ( 1.0 分) (组内16/93) 切至整卷模式 搜藏此题  
  When an object is released from rest and falls in the absence of friction, whi 2u/ 6ufed(qimch of the following is true conceequ(m6 fi /du2rning its motion?

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17#
 
单选题 ( 1.0 分) (组内17/93) 切至整卷模式 搜藏此题  
  When an object is released fri)cb/; + skmpdom rest and falls in the absence of friction, which of the following is true cod+p mi/bs)k c;ncerning its motion?

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18#
 
单选题 ( 1.0 分) (组内18/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown sy 3d j/l-4ntylzd 9x1p gwr;d6traight up. Make a statement about the velocity and the acceleration when th-j 3lt9px 1dd/dy ly n;gwr64ze ball reaches the highest point.

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19#
 
单选题 ( 1.0 分) (组内19/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown straight u,1,cexp s0jrbo/6wx i (pyy;qp. What is its acceleration just before it reacs1( pexo, /6priqcxjb y,w;y0hes its highest point?

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20#
 
单选题 ( 1.0 分) (组内20/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrown straight up, reaches a mahvr,6 gv,h(km9rb nt5 ximum height, then falls to its initial height. hrm9,r 6n,gvkbt5v( hMake a statement about the direction of the velocity and acceleration as the ball is going up.

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21#
 
单选题 ( 1.0 分) (组内21/93) 切至整卷模式 搜藏此题  
  A ball is thrown straight up, reaches a maximum height, then falls tol88v0x+fn+qj3 jtw yu its initial heiw 8yt3qj8lun +j +vfx0ght. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

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22#
 
单选题 ( 1.0 分) (组内22/93) 切至整卷模式 搜藏此题  
  Suppose a ball is thrs/j2mq4z 2(uraw9kx 5ep1 lytown downward in the absence of air resistance. Make a statement cq/w5au1(xjp2s2 9 lz mye4rktoncerning its acceleration.

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23#
 
单选题 ( 1.0 分) (组内23/93) 切至整卷模式 搜藏此题  
  Suppose a skydiver ju9 :g l06as*m w3hyv/xo bpz5pbmps from a high-flying plane. What is her acceleration when she she reaches termin 3hv9p /b bszp0og:wax*5myl6al velocity?

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24#
 
单选题 ( 1.0 分) (组内24/93) 切至整卷模式 搜藏此题  
  A ball is thrown vertically upward with a speed v. An identicawra+h2en rs9edn fh s3j49d/aa( f4,el second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the a,9r /wnfah(+ee fr3n de d2s s449jhasecond ball go than the first ball?)

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25#
 
单选题 ( 1.0 分) (组内25/93) 切至整卷模式 搜藏此题  
  Ball A is dropped from the top of a building. One second ,xf ogh,c-bpm)vdfvi k9v a.8 c8w0/mlater, ball B is dropped from 9f 0mv aw/vfvmikp8,,-)h8cdb.xgc o the same building. As time progresses, the distance between them

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26#
 
单选题 ( 1.0 分) (组内26/93) 切至整卷模式 搜藏此题  
  Ball A is dropped from the top of a building. One second later, bj zbt2/;ferizp6ko0n;k+qa: nny 2)a all B is dropped from the same building. As time progresses, the difference ianqenjr)i on ;6 a2k;bt0zy 2p+k/fz:n their speeds

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27#
 
单选题 ( 1.0 分) (组内27/93) 切至整卷模式 搜藏此题  
  Two objects are thrown from the top of a tall bbekpo a*6i/l3uilding. One is thrown up, and the other is thrown down, both with the same initial speed. What arbl6 /*ipkoae3e their speeds when they hit the street?

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28#
 
单选题 ( 1.0 分) (组内28/93) 切至整卷模式 搜藏此题  
  A brick is dropped from the top of a buil+jsv2 j* h+b8pr3i tflding. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bhv* jrsl+p 832ib+tjfricks.

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29#
 
单选题 ( 1.0 分) (组内29/93) 切至整卷模式 搜藏此题  
  An object is moving with constant non-zero velocity in the +x axis. The positio7zaovfc be p cr871klk(y4v 19n vcfcv17zp b8y(7kk1 4oer9la versus time graph of this object is

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30#
 
单选题 ( 1.0 分) (组内30/93) 切至整卷模式 搜藏此题  
  An object is moving we.opf5h bk 12iith constant non-zero acceleration in the +x axis. The position versus time graph of this 1hp.ko e5 i2bfobject is

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31#
 
单选题 ( 1.0 分) (组内31/93) 切至整卷模式 搜藏此题  
  An object is moving with constant vn01gzz6hrw)gq 0 dxl,0q )yknon-zero velocity in the +x axis. The velocity versus time gra10)wzqgd60k ,l zx0r g )hqnvyph of this object is

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32#
 
单选题 ( 1.0 分) (组内32/93) 切至整卷模式 搜藏此题  
  An object is moving with constant non-zero acceleration in the +x axis. T+cm od)b 8daq,r20kf khe velocity versus time km0bka2d), q+ 8rdf cograph of this object is

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33#
 
单选题 ( 1.0 分) (组内33/93) 切至整卷模式 搜藏此题  
  The slope of a position versv t3kq2k+z3inscl( i 7us time graph gives

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34#
 
单选题 ( 1.0 分) (组内34/93) 切至整卷模式 搜藏此题  
  The slope of a velocity versus time grap9 u 4ob tm8hjz(p3(u els;:wkch gives

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35#
 
单选题 ( 1.0 分) (组内35/93) 切至整卷模式 搜藏此题  
  The area under a curve in an accelepe0y0 g+ zhr lb8 vw3ja)bhf4)ration versus time graph gives

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36#
 
单选题 ( 1.0 分) (组内36/93) 切至整卷模式 搜藏此题  
  The area under a curve in a velocity versus time graph g-yrc yeb++u): aenko;ives

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37#
 
单选题 ( 1.0 分) (组内37/93) 切至整卷模式 搜藏此题  
  If the position versus time graph of an object is a ht+6ok4ppm6 umn h,- buorizontal line, the object itumpo6,nmk6p 4 u+-hbs

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38#
 
单选题 ( 1.0 分) (组内38/93) 切至整卷模式 搜藏此题  
  If the position versus time graph of 08g75 zsh vglx:poxf8an object is a vertical line, the object issxghp:vzfog78 l5 0 8x

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39#
 
单选题 ( 1.0 分) (组内39/93) 切至整卷模式 搜藏此题  
  If the velocity versus time graph of an object is a horizontal line, the ob pzd( 88t ce*s5rv)ndpzvb i;6ject i c ;56zn i s)(pv8tdv8edbrzp*s

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40#
 
单选题 ( 1.0 分) (组内40/93) 切至整卷模式 搜藏此题  
  If the velocity versus time graph of an object is a straight line making an3fgh/o;sb-mztplet 0 /0vj y ,sgd4u( angle of g3h /( 0zf/s-gldve op;by s4,tjmt0u 30 degrees with the time axis, the object is

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41#
 
单选题 ( 1.0 分) (组内41/93) 切至整卷模式 搜藏此题  
  An object moves 15.0 m nbm/61nkklb 8 lorth and then 11.0 m south. Find both the distance traveled and the magnitb 8nkkl1 /mlb6ude of the displacement vector.

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42#
 
单选题 ( 1.0 分) (组内42/93) 切至整卷模式 搜藏此题  
  A boat can move at 30 km/h in still water. How long will it +zy *khc qgl7c.i5aahn ;,mc/take to move 12 km upstream in a river flh, yag;czc ni* cmk/q5.ha+l7owing 6.0 km/h?

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43#
 
单选题 ( 1.0 分) (组内43/93) 切至整卷模式 搜藏此题  
  55 mi/h is how many m/s? (1 mi = 16gy+r0ul asv 1609 m)

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44#
 
单选题 ( 1.0 分) (组内44/93) 切至整卷模式 搜藏此题  
  What must be your average speed in4*q6/x 2vtugd1comgy order to travel 350 km in 5.15 h?

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45#
 
单选题 ( 1.0 分) (组内45/93) 切至整卷模式 搜藏此题  
  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57z8-mf6.pz:/m38wsk s vr jonz min. What is the averajw8 o6s n8v3mz.zzpkf/m:-s rge speed of the runner in m/s?

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46#
 
单选题 ( 1.0 分) (组内46/93) 切至整卷模式 搜藏此题  
  A car travels 90 km/h. How long does it take for it t+c x(ggis e4,wo travel 400 km?

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47#
 
单选题 ( 1.0 分) (组内47/93) 切至整卷模式 搜藏此题  
  A ly (light year) is the distance that light travels in one ycle v-o q4d0a2ear. The speed of l0v -2qoac4 edlight is $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

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48#
 
单选题 ( 1.0 分) (组内48/93) 切至整卷模式 搜藏此题  
  If you are driving 72 km/h along a straight road and you look to th1x4tt:/ irc1d:hjc x0qkmlo /e side for 4.0 s, how far do you traveljd 41 mtl 1:i c/0or:x/qhkxtc during this inattentive period?

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49#
 
单选题 ( 1.0 分) (组内49/93) 切至整卷模式 搜藏此题  
  If you run a complete loop xzfz5q/kpvl.3y (y jm(n +ph9around an outdoor track (400 m), in 100 s, your average velocity isy3z. 9((py+fxpk5zqhnjlv m /

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50#
 
单选题 ( 1.0 分) (组内50/93) 切至整卷模式 搜藏此题  
  A polar bear starts at the North Pole. It travels 1.0 km f3 6 etgrrc-;isouth, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45f36- egirrtc ; min. What was the bear's average speed?

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51#
 
单选题 ( 1.0 分) (组内51/93) 切至整卷模式 搜藏此题  
  A polar bear starts at the North Pole. It travels 1.0 km south, the3b1+fep)fzgb -in t+xn 1.0 km east, then in)1zbf-e bft p3gx++ 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. What was the bear's average velocity?

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52#
 
单选题 ( 1.0 分) (组内52/93) 切至整卷模式 搜藏此题  
  You are driving home on a weekend from school at 55 mi/h for 110 mile92 dmwlso(ne6jb-tb 7s. It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and -bjml2o9d( 6e7bnt ws 15 minutes. How far is your hometown from school?

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53#
 
单选题 ( 1.0 分) (组内53/93) 切至整卷模式 搜藏此题  
  A motorist travels 160 km at 80 km/h and 160 km j . s4utsw6jc+at 100 km/h. What is the average spees +ctj4uw .6sjd of the motorist for this trip?

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54#
 
单选题 ( 1.0 分) (组内54/93) 切至整卷模式 搜藏此题  
  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is herxcnqw*yjf*472o xq ,n average 4x c*nwnojf72 q,qyx* speed for the trip?

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55#
 
单选题 ( 1.0 分) (组内55/93) 切至整卷模式 搜藏此题  
  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north fhu-n3 j .fyx4;g1d6 5tinuyjcor 750 miles.-x6 f5j;nyg dyj.cu 41ihtun 3 What is the average speed for the trip?

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56#
 
单选题 ( 1.0 分) (组内56/93) 切至整卷模式 搜藏此题  
  In a 400-m relay race the anchorman (the pn5* kyyei-yx .erson who runs the last 100 m) for team A can run 100 m in 9.8 s. His rival, the anchorman for team B, can cover 100 m in 10.1 s. What is the largest lead the teynyk5-iy.x e* am B runner can have when the team A runner starts the final leg of the race, in order that the team A runner not lose the race?

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57#
 
单选题 ( 1.0 分) (组内57/93) 切至整卷模式 搜藏此题  
  A car decelerates uniformly and comel2 )iteyt4s) s2exy/as to a stop after 11 s. The car's average velocity during deceleration was 47 km/h. What was the car's deceleration )xas l i2s)yt2e/4teywhile slowing down?

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58#
 
单选题 ( 1.0 分) (组内58/93) 切至整卷模式 搜藏此题  
  An airplane increases its speed from 100 m/s to 160 m/s, at the avfed q f t6,qm )hhcvv(2;5a(okerage rate of )q,5kvv((q;cmh ta h2df e6of$15 \; m/s^2$. How much time does it take for the complete increase in speed?

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59#
 
单选题 ( 1.0 分) (组内59/93) 切至整卷模式 搜藏此题  
  A car traveling 60 km/h accelerates at the rate o 1ujrgn*f9a3utg gid t** 8r1fjs -y:af $2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

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60#
 
单选题 ( 1.0 分) (组内60/93) 切至整卷模式 搜藏此题  
  A cart starts from rest xq6ccpe8g(ptsxwpg1q. ( -p) and accelerates at $4.0 \; m/s^2$ for 5.0 s, then maintain that velocity for 10 s, and then decelerates at the rate of $2.0 \; m/s^2$ for 4.0 s. What is the final speed of the car?

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61#
 
单选题 ( 1.0 分) (组内61/93) 切至整卷模式 搜藏此题  
  A car travels at 15 m/s for 10 s. It then speeds up withwx+f h 78ui5d(nvmik (cm8+j,m*rqxt a constant acceleration oq( d8+,mnx5m7 i 8*w k +uixhfv(rtcmjf $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

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62#
 
单选题 ( 1.0 分) (组内62/93) 切至整卷模式 搜藏此题  
  A cart with an initia5tr5btgblv5nvc 0-3c 4k ap5ul velocity of 1.7 m/s experiences a constant acceleration of5g5k5 450r-ab tpvc3vnbltuc $2.8 \; m/s^2$. What is the cart's displacement during the first 9.8 s of its motion?

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63#
 
单选题 ( 1.0 分) (组内63/93) 切至整卷模式 搜藏此题  
  A bullet moving horizontally to th)4md j+guv 2zse right (+x direction) with a speed of 505 m/s strikes+vs)2 4zmg duj a sandbag and penetrates a distance of 49.12 cm. What is the average acceleration, in $m/s^2$, of the bullet?

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64#
 
单选题 ( 1.0 分) (组内64/93) 切至整卷模式 搜藏此题  
  A jet fighter plane is launched from a catapult on an air arpcknsdn :5*xr /z9e :10caycraft carrier. It reachzc:a 9n1n/akyre:p* cx drs50es a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

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65#
 
单选题 ( 1.0 分) (组内65/93) 切至整卷模式 搜藏此题  
  A car starting from rest moves wits/x 1rzfl ,7vnh constant acceleration of $2.0 \; m/s^2$ for 10 s, then travels with constant speed for another 10 s, and then finally slows to a stop with constant acceleration of
-$2.0 \; m/s^2$. How far does it travel?

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66#
 
单选题 ( 1.0 分) (组内66/93) 切至整卷模式 搜藏此题  
  A car goes from 40 m/s to 80 m/s in a distance of 200 m. What is its 2c u* wmhkj1 c8k;nssax9+r; maverage accele8kmx1jmrkhu sa;s2;c+w c n*9ration?

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67#
 
单选题 ( 1.0 分) (组内67/93) 切至整卷模式 搜藏此题  
  An object starts from rest and undergoes unifokdxspxe- ajor5 m5zw8,t1k .9rm acceleration. During the first second it travels 9.3 m. How far will it travel during the third second?o58- 5ktpm jsw1,da . rkxxez9

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68#
 
单选题 ( 1.0 分) (组内68/93) 切至整卷模式 搜藏此题  
  An object is moving in a straight line withue6ki .gm5k e:pf a /aln7pue4i) y/v) constant acceleration. Initially it is traveling au6i)5u/ev p)a7ge. m4yk/:el k pnafi t 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

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69#
 
单选题 ( 1.0 分) (组内69/93) 切至整卷模式 搜藏此题  
  A car starts from re2bl; eh-3 dnbnst and accelerates uniformly at $3.0 \; m/s^2$. A second car starts from rest 6.0 s later at the same point and accelerates uniformly at $5.0 \; m/s^2$. How long does it take the second car to overtake the first car?

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70#
 
填空题 ( 2.0 分) (组内70/93) 切至整卷模式 搜藏此题  
  A car with good tires o bn5xc+xlo0c)vqb o.fx iw1m-6u,x0 ; jz:j bwn a dry road can decelerate at about $5.0 \; m/s^2$ when braking. Suppose a car is initially traveling at 55 mi/h.
(a.) How much time does it take the car to stop?    $s$ (only input numerical values)
(b.) What is the stopping distance?    $m$ ((only input numerical values)

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71#
 
填空题 ( 3.0 分) (组内71/93) 切至整卷模式 搜藏此题  
  At the instant a traffic light turns green, a car that has been twcilu 8na/h7ebj m ip zo.4w5*4vt62waiting at the intersection starts ahead with a constant accele*4o c7/ 5 mapwih .w4n8tv2utijzbl6eration of $2.00 \; m/s^2$. At that moment a truck traveling with a constant velocity of 15.0 m/s overtakes and passes the car.
(a.) Calculate the time necessary for the car to reach the truck.    $s$ (only fill in numerical values)
(b.) Calculate the distance beyond the traffic light that the car will pass the truck.    $m$ (only fill in numerical values)
(c.) Determine the speed of the car when it passes the truck.    $m/s$ (only fill in numerical values)

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72#
 
单选题 ( 1.0 分) (组内72/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a ssg e8c; z5+zffpeed of 12 m/s on the surface of planet X where the acceleration due to gr8g e+ff zs;z5cavity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

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73#
 
单选题 ( 1.0 分) (组内73/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of 12 m/s on the7s n 2:q5ne8osr :bdgsamwc vb-+ cr0) surface of planet X where the acceleration due to gra:qb cn02b )n m vcs5ser8r+odw:a -gs7vity is $1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

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74#
 
单选题 ( 1.0 分) (组内74/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of 15 m/s on tf ,jgmfj5 rqp :u-9q,hhe surface of planet X where the acceleratq,m: r-hugf9jj p5,fqion due to gravity is $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

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75#
 
单选题 ( 1.0 分) (组内75/93) 切至整卷模式 搜藏此题  
  An object is thrown upward with a speed of 14 m/s:jgyyr5wpta9mfhkih1c fd(k+ 50/v 0, c7 fg f on the surface of planet X where 0a1 d59/fgfphtc7jmy:r f yg fkhi,0ck5 wv(+the acceleration due to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

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76#
 
单选题 ( 1.0 分) (组内76/93) 切至整卷模式 搜藏此题  
  Human reaction time is usually greater than 0.10 s. If your friend holds a rtqo 3i g5;o,ehuler between your fingers and releases it without warning, how far can you expect the ruleri,oto5qg h3 e; to fall before you catch it?

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77#
 
单选题 ( 1.0 分) (组内77/93) 切至整卷模式 搜藏此题  
  A ball is thrown upward at lb ku6cf(g5c8xmyi7/8d2 d6f2l nk fm a velocity of 19.6 m/s. What is its velocity after 3.00 c /xfd 8u72mlbmy 8nc26 fgk k56ldf(is?

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78#
 
单选题 ( 1.0 分) (组内78/93) 切至整卷模式 搜藏此题  
  A bullet shot straight up returns to its startind2x;8vg/ sdtyc1rfqlcma.5 7 g point in 7 s. What is the initial sc vrt c521msxg.dl8yaq;7/dfpeed of the bullet?

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79#
 
单选题 ( 1.0 分) (组内79/93) 切至整卷模式 搜藏此题  
  A ball is thrown straight up with a speed of 36.0 m/s. How lonwd:xtt dj b*) +odhln (5i3q;tg does it take to return to 5xb ;l niq ddj(3d:h)ttt+wo*its starting point?

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80#
 
单选题 ( 1.0 分) (组内80/93) 切至整卷模式 搜藏此题  
  A ball is thrown downward from the top of9s d5ir,y2jptm1 ka+f a building with an initial speed of 29 m/s. It strtdkf+s,i2yj1r 9p ma5ikes the ground after 6.7 s. How high is the building?

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81#
 
填空题 ( 3.0 分) (组内81/93) 切至整卷模式 搜藏此题  
  A ball is thrown straight up wn vr* 0olkss15z7zzl4ith a speed of 30 m/s. (only fill in numerical value inz5*7r v skzon4ls0l z1 the blanks)
(a.) How long does it take the ball to reach the maximum height?    $s$
(b.) What is the maximum height reached by the ball?    $m$
(c.) What is its speed after 4.2 s?    $m/s$

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82#
 
填空题 ( 6.0 分) (组内82/93) 切至整卷模式 搜藏此题  
  A foul ball is hit straight up into the air with a speed of 20.9 m/s. (c9zg8(yz/co s8 ez,j;npqc 4x use $g=10 \; m/s^2$, only fill in numerical value in the blank)
(a.) Calculate the time required for the ball to rise to its maximum height.  (数值)  $s$
(b.) Calculate the time for the ball to fall back to the height at which it was hit.  (数值)  $s$
(c.) Calculate the maximum height reached by the ball.  (数值)  $m$
(d.) Calculate the ball's speed 2 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 8 m above the point of contact between the bat and ball for the first time.  (数值)  $s$
(f.) Determine the time at which the ball pass a point 8.0 m above the point of contact a second time.  (数值)  $s$

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83#
 
单选题 ( 1.0 分) (组内83/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the velocity at t = 1.0 sy/0 xvriu +a5k?


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84#
 
单选题 ( 1.0 分) (组内84/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is vkm z d;za0hut-h;p( f:gv14m the velocity at t = 2.5 s?


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85#
 
单选题 ( 1.0 分) (组内85/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the w 5,4( gn2cxodp/p n2cmim;tjvelocity at t = 4.0 s?


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86#
 
单选题 ( 1.0 分) (组内86/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the velocm3(5 v h h2ax ;c2jx5xetfv3lxity at t = 5.5 s?


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87#
 
单选题 ( 1.0 分) (组内87/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the average velocity from 0 to 4rq9n7e,s z8pq*mye p4.0 s?


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88#
 
单选题 ( 1.0 分) (组内88/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the average velocity from 0 to 6.0 sd1 n:9nvg46olh+yfs f jse7n;?


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89#
 
单选题 ( 1.0 分) (组内89/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the acceleratz 0vofh86( v 7pehyr4:ra4gtkion at 1.0 s?


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90#
 
单选题 ( 1.0 分) (组内90/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the accelerationy ml16gnt ,ef a;i8zbju:y w1y9l*4wn at 3.0 s?


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91#
 
单选题 ( 1.0 分) (组内91/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the average acceleration fromajma/wips 81v- p637koi1ick 0 to 5.0 s?


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92#
 
单选题 ( 1.0 分) (组内92/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the4 -uol/qgt m2z1sj9mg average acceleration from 0 to 8.0 s?


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93#
 
单选题 ( 1.0 分) (组内93/93) 切至整卷模式 搜藏此题  
  In Fig. below, what is the displacement from+vb2uv4f7ne6u z 5mdue+ 6aiggw-gc+ 0 to 8.0 s?


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94#
 
问答题 ( 1.0 分) (组内1/46) 切至整卷模式 搜藏此题  
第 2 题组 (共 46 题 46 分)
Does a car speedometer measure speed, velocity? {spuaqyd3b 8 (uf-h2+ w.foiah)weed|velocity}
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95#
 
判断题 ( 1.0 分) (组内2/46) 切至整卷模式 搜藏此题  
  An object can have a varying speed if its velojhatfca 4550mcity is constant.

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96#
 
判断题 ( 1.0 分) (组内3/46) 切至整卷模式 搜藏此题  
  The velocity of an object can be negative when its acceleration is posit4 hg;4d*dzqdtive.

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97#
 
判断题 ( 1.0 分) (组内4/46) 切至整卷模式 搜藏此题  
  If one object has a greater speed than a second object, the firsms n6cxyt ; y9r4th,b,t must have a greater accele;,ty cmb9hrx6t4 ,synration.

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98#
 
判断题 ( 1.0 分) (组内5/46) 切至整卷模式 搜藏此题  
  Two cars emerge side ae,y c9 qht,q+by side from a tunnel. Car A is traveling with a speed of $60 \; km/h$ and has an acceleration of $40 \; km/h/min$ Car B has a speed of $40 \; km/h$ and has an acceleration of $60 \; km/h/min$ . Can A will pass car B at the instant they come out of the tunnel.

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99#
 
判断题 ( 1.0 分) (组内6/46) 切至整卷模式 搜藏此题  
  An object can be increasing in speed as its acceleratio 2ehcw4):ozl9xpv wk5n decreases.

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100#
 
填空题 ( 1.0 分) (组内7/46) 切至整卷模式 搜藏此题  
  A baseball player hits a foul ball straight up ini+ es( 0b )-df,p(sfv avg.qkuto the air. It leaves the bat with a speed o,- 0ea.dvbkf sifp s+u(qvg)(f $120 \; km/h$. In the absence of air resistance, how fast will the ball be traveling when the catcher catches it?    $km/h$ (please only fill in numerical value in the blank)

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101#
 
单选题 ( 1.0 分) (组内8/46) 切至整卷模式 搜藏此题  
  As a freely falling object speeds up, what is happening to its acceleration, ;eie. kr/bxf)how does it change if air friction is ignor/k.;xi refb )eed?

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102#
 
单选题 ( 1.0 分) (组内9/46) 切至整卷模式 搜藏此题  
  As a freely falling object0gw7p hq b9u/woohf; , speeds up, what is happening to its acceleration, how does it change if air friction CAN NOT be iwg;7h,h9p/u0f oqbw ognored?

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103#
 
单选题 ( 1.0 分) (组内10/46) 切至整卷模式 搜藏此题  
  An object that is thrown vertically upwc) xfapyd wrg-*1jng e7m3v,(ard will return to its original position with the same speed a)gf yrd(3m*ej7- p xvcga,w1 ns it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

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104#
 
判断题 ( 1.0 分) (组内11/46) 切至整卷模式 搜藏此题  
  An object can have zero velocity and nonzero acceleration (ywz(xoz: ;yt5(c4a htqat3hat the same time.

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105#
 
判断题 ( 1.0 分) (组内12/46) 切至整卷模式 搜藏此题  
  An object can have noq7mwg63lv*s0-y i ok znzero velocity and zero acceleration at the same time.

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106#
 
判断题 ( 1.0 分) (组内13/46) 切至整卷模式 搜藏此题  
  An elevator moving from e.2nw 5zmsco3+ -txdzthe second floor to the fifth floor making no stops along the way has zero acceleration all t oedc 5z3 m2wtxz-.+snhe time.

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107#
 
填空题 ( 1.0 分) (组内14/46) 切至整卷模式 搜藏此题  
  A rolling ball moves 4hxhme oakb)+n7 j-(dwu/dc* g+k p- mfrom $x_1=3.0 \mathrm{~cm}$ to $x_2=-6.1 \mathrm{~cm}$ during the time from $t_1=2.2 \mathrm{~s}$ to $t_2=5.2 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

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108#
 
填空题 ( 1.0 分) (组内15/46) 切至整卷模式 搜藏此题  
  A particle at $t_1=-3.0 \mathrm{~s}$ is at $x_1=3.3 \mathrm{~cm}$ and at $t_2=4.3 \mathrm{~s}$ is at $x_2=8.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

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109#
 
填空题 ( 1.0 分) (组内16/46) 切至整卷模式 搜藏此题  
  A person jogs eight complete laps ar .v c:z:cp qh,ox7j.kqound a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 9.2 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

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110#
 
填空题 ( 1.0 分) (组内17/46) 切至整卷模式 搜藏此题  
  A horse canters away from its trainer in a st2-pz;vq8w ywtraight line, moving 108 m away in 8.1 s. It then turns abruptzp2wytq; -w 8vly and gallops halfway back in 4.7 s. Calculate (a) its average speed  (数值)  $m/s$ and (b) its average velocity  (数值)  $m/s$ for the entire trip, using “away from the trainer” as the positive direction.

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111#
 
填空题 ( 1.0 分) (组内18/46) 切至整卷模式 搜藏此题  
  A car accelerates from/bk3zg/r n5qbacv-4 sj 6u ha3 $11 \; m/s$ to $25 \; m/s$ in 5.4 s. What was its acceleration?  (数值)  $m/s^2$ How far did it travel in this time?  (数值)  $m$ Assume constant acceleration.

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112#
 
填空题 ( 1.0 分) (组内19/46) 切至整卷模式 搜藏此题  
  A car slows down fromhge3:)h6 5y2 ykuvmvh $16 \; m/s$ to rest in a distance of 64 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

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113#
 
填空题 ( 1.0 分) (组内20/46) 切至整卷模式 搜藏此题  
  A light plane must reach a spe- t o0ysk3ll:(wy(sgied of $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.6 \; m/s^2$ ?  (数值)  $m$

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114#
 
填空题 ( 1.0 分) (组内21/46) 切至整卷模式 搜藏此题  
  A world-class sprinter can burst out of f fy/v ) gtzshu*rn39hsb 5*w9the blocks to essentially top speed abou3w h*/ fr)u*s zgf9nthbs9yv5t $10.9 \; m/s$ in the first 12.7 m of the race. What is the average acceleration of this sprinter?  (数值)  $m/s^2$ and how long does it take her to reach that speed?  (数值)  $s$

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115#
 
填空题 ( 1.0 分) (组内22/46) 切至整卷模式 搜藏此题  
  A car slows down unifwk a2i6bd x/-bormly from a speed of $17 \; m/s$ to rest in 4.55 s. How far did it travel in that time?  (数值)  $m$

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116#
 
填空题 ( 1.0 分) (组内23/46) 切至整卷模式 搜藏此题  
  In coming to a stop, a car leaves skik bf 2j1uuvh0;(k1 hhid marks 92 m long on the highway. Assuming a dek ; h 1(2h01kbuhjfuivceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

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117#
 
填空题 ( 1.0 分) (组内24/46) 切至整卷模式 搜藏此题  
  A car is behind a truc 9m6ji3aw tai/ d12pnyk going $25 \; m/s$ on the highway. The car’s driver looks for an opportunity to pass, guessing that his car can accelerate at $1.0 \; m/s^2$. He gauges that he has to cover the 20-m length of the truck, plus 10 m clear room at the rear of the truck and 10 m more at the front of it. In the oncoming lane, he sees a car approaching, probably also traveling at $25 \; m/s$. What is the closest distance of the approaching car that he can still sately make the attempt to pass the truck? (without hitting the approaching car).    $m$

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118#
 
填空题 ( 1.0 分) (组内25/46) 切至整卷模式 搜藏此题  
  A runner hopes to com1yan0v-8rkvk 0z2cm xu28 lnq plete the 10,000-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then accelerate8q2v -zx8nau1 r vn0k2 cy0mlk at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$

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119#
 
填空题 ( 1.0 分) (组内26/46) 切至整卷模式 搜藏此题  
  A stone is dropped from the top of a cliff. It hits8fk8dt47gh4r/a pmys the ground below after $1.62 \; s$. How high is the cliff?  (数值)  $m$

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120#
 
填空题 ( 1.0 分) (组内27/46) 切至整卷模式 搜藏此题  
  Estimate (a) how long it took a stone to fall stra-suead* jt ys;a8h8o5ight down from the top of the Empire Stathda;*oss58 a-juyet 8 e Building (368 m high)  (数值)  $s$, and (b) its velocity just before landing?  (数值)  $m/s$

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121#
 
填空题 ( 1.0 分) (组内28/46) 切至整卷模式 搜藏此题  
  A baseball is hit nearly straight up into the air with a speed2; aysmwj1nk ykt d3*3 of $20 \; m/s$. (a) How high does it go?  (数值)  $m$ (b) How long is it in the air?  (数值)  $s$

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122#
 
填空题 ( 1.0 分) (组内29/46) 切至整卷模式 搜藏此题  
  A ballplayer catches a be98u x afh9xp*all 2.2 s after throwing it vertically upward. (a) With what speed did he throw pa 8fxe9*uh 9xit?  (数值)  $m/s$ and (b) what height did it reach?  (数值)  $m$

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123#
 
填空题 ( 1.0 分) (组内30/46) 切至整卷模式 搜藏此题  
  A helicopter is ascending vertically wiommlu9 *5;j:. 6 +t nxoencydeth a speed of $5.03 \; m/s$. At a height of 121 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground?  (数值)  $s$
[Hint: The package’s initial speed equals the helicopter’s.]

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124#
 
填空题 ( 1.0 分) (组内31/46) 切至整卷模式 搜藏此题  
  A stone is thrown vertically upward with a speedp,cr ejg0h m*1q:x)jmd wc1v2 of $16 \; m/s$. (a) How fast is it moving when it reaches a height of 10.4 m?  (数值)  $m/s$ (b) How long is required to reach this height for the first time?  (数值)  $s$ (c) How long is required to reach this height for the second time?  (数值)  $s$

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125#
 
填空题 ( 1.0 分) (组内32/46) 切至整卷模式 搜藏此题  
  A falling stone takes 0.17 s 3bnbq ; a a9jy/v.4zyp/n0fmag.:hcb to travel past a window 2.0 m tall. From what height above the top of the wi:3p/ c.nn aa;4mqbb9f.bjv hyaz/0gyndow did the stone fall?  (数值)  $m$


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126#
 
填空题 ( 1.0 分) (组内33/46) 切至整卷模式 搜藏此题  
  A rock is dropped from a sea cliff, and the sound of it strikingiy t4j k 3jyemso8eb*1: cg,n. the ocean is heard 2*enm8gy1.kyji3oe s c:4t, jb .4 s later. If the speed of sound is $340 \; m/s$, how high is the cliff?  (数值)  $m$

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127#
 
填空题 ( 1.0 分) (组内34/46) 切至整卷模式 搜藏此题  
  A stone is thrown vertical 2h3m9 j(vpocply upward with a speed of $11 \; m/s$ from the edge of a cliff 41.3 m high (a) How much later does it reach the bottom of the cliff?  (数值)  $s$ (b) What is its speed just before hitting?  (数值)  $m/s$ (c) What total distance did it travel?  (数值)  $m$

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128#
 
填空题 ( 1.0 分) (组内35/46) 切至整卷模式 搜藏此题  
  A baseball is seen to pass upward b4c g/ 0 eqwvg5jcgex7/y someone on the 9th floor (28 m above the street) with a vertex/q v7g/5 cg0jcew4gical speed of $10 \; m/s$. If the ball was thrown from the street, (a) what was its initial speed?  (数值)  $m/s$ (b) what maximum altitude does it reach?  (数值)  $m$ (c) how many seconds ago was the baseball thown from the street?  (数值)  $s$ (c) In how many seconds will it reach the street again?  (数值)  $s$

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129#
 
填空题 ( 1.0 分) (组内36/46) 切至整卷模式 搜藏此题  
  The acceleration due to gbna 6z :w6kmc)ravity on the Moon is about one-sixth what it is on Earth. If an object is thrown vertically upward on the Moon, how many times higher will it go than it w)6cmz b6nkw :aould on Earth, assuming the same initial velocity?    $times$

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130#
 
填空题 ( 1.0 分) (组内37/46) 切至整卷模式 搜藏此题  
  A 95-m-long train begins uniform acceleration from rest. The front of the dujos 7ph0sp5f4 )h1 htrain has a speed of hdoshp7 us 4h0) pfj51$10 \; m/s$ when it passes a railway worker who is standing 173 m from where the front of the train started. What will be the speed of the last car of the train as it passes the worker?  (数值)  $m/s$

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131#
 
填空题 ( 1.0 分) (组内38/46) 切至整卷模式 搜藏此题  
  A fugitive tries to hop on a freight train traveling at ailbqh 390 e6qsz p ax6w/+lxb3 constant speed of $6.0 \; m/s$. Just as an empty box car passes him, the fugitive starts from rest and accelerates at $a=4.0 \; m/s^2$ to his maximum speed of $8.0 \; m/s$. (a) How long does it take him to catch up to the empty box car?    $s$ (b) What is the distance traveled to reach the box car?    $m$

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132#
 
填空题 ( 1.0 分) (组内39/46) 切至整卷模式 搜藏此题  
  A stone is dropped from the roo 8ggi2gs ddx2;f of a high building. A second stone is dropped 1.39 s later. How far apart are gdig 28xgs;2 dthe stones when the second one has reached a speed of $10 \; m/s$?  (数值)  $m$

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133#
 
填空题 ( 1.0 分) (组内40/46) 切至整卷模式 搜藏此题  
  A race car driver mu3::) ike qq-htxd fcb0st average $200 \; km/h$ over the course of a time trial lasting ten laps. If the first nine laps were done at $192 \; km/h$, what average speed must be maintained for the last lap?  (数值)  $km/h$

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134#
 
填空题 ( 1.0 分) (组内41/46) 切至整卷模式 搜藏此题  
  A rocket rises vertically, from rest, with an t)q-xgnndd(xg8r3:n vv 8xw0acceleration of $3.2 \; m/s^2$ until it runs out of fuel at an altitude of 1200 m. After this point, its acceleration is that of gravity, downward.
(a) What is the velocity of the rocket when it runs out of fuel?    $m/s$
(b) How long does it take to reach this point?    $s$
(c) What maximum altitude does the rocket reach?    $m$
(d) How much time (total) does it take to reach maximum altitude?    $s$
(e) With what velocity does the rocket strike the Earth?    $m/s$
(f) How long (total) is it in the air?    $s$

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135#
 
填空题 ( 1.0 分) (组内42/46) 切至整卷模式 搜藏此题  
  A stone is dropped from the roof of a building; 1.87 s after that, a second s)yh)j w t:cg8p j,cnd6tone is thrown dj:8y) cw,h)tg6cjnpstraight down with an initial speed of $25 \; m/s$ and the two stones land at the same time.
(a) How long did it take the first stone to reach the ground?  (数值)  $s$
(b) How high is the building?  (数值)  $m$
(c) What is the speed of the first stone just before it hit the ground?  (数值)  $m/s$
(d) What is the speed of the second stone just before it hit the ground?  (数值)  $m/s$

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136#
 
填空题 ( 1.0 分) (组内43/46) 切至整卷模式 搜藏此题  
  If there were no air resistance, how long would it take avneow .jp90q /rlr//a free-falling parachutist to fall from a plane at 3265 m to an altitude o/nj wlq9vo0ra e/r/p. f 350 m, where she will pull her ripcord? What would her speed be at 350 m? (In reality, the air resistance will restrict her speed to perhaps must lower value)  (数值)  $m/s$

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137#
 
填空题 ( 1.0 分) (组内44/46) 切至整卷模式 搜藏此题  
  Bill can throw a ball verticallgf ie 7bpr4o-8n uw++ly at a speed 1.2 times faster than Joe can. How many times higherur+-8 on7 iw+p4fe lgb will Bill’s ball go than Joe’s?  (数值)  $times$

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138#
 
填空题 ( 1.0 分) (组内45/46) 切至整卷模式 搜藏此题  
  You stand at the top of a cliff while your friend stands on the ground belowf .)ed )l afox44/d:az 5haql2bdvs2y you. You drop a ball from rest and see that it takes 1.1 s for the ball to hit the ground below. Your friend then picks up the ball and throws it up to you, such that it just comes to rest xd.:/fa)l4a4sq2e2 d 5bofavlz d y h)in your hand. What is the speed with which your friend threw the ball?  (数值)  $m/s$

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139#
 
填空题 ( 1.0 分) (组内46/46) 切至整卷模式 搜藏此题  
  Two students are asked to fdvpiyj w9 bh3w6 e)( + poana,.d+w.dfind the height of a particular building. They take a stone to the roof of the building and drop it off, timing its fall. One student reports a fall time of 2.0 s, and the other, 2.2 s. How much difference does the difference in time makeh)jf+peovwbn ,awpda +d.w .i3 y6d(9 for the estimates of the building’s height?  (数值)  $m$

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