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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 com r4km8dlb/ j:7od3aa kparison be3k k raamd7lj4/:bdo8 tween the 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 the io yy yg,ny o1b i+)no+lm:3ki4nstantaneous 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 their car can go "from zero to sixty i0cp *arf-axeu) bd65w/9isven 8 s". This is a dvr0ad/sc x*-eiwfe6a9)pu5b escription 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 axis experiences an accea/(*)lannki6r65 h k c8vghxtleration 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 traveling to the East (+x direction) begins al9yfzktmr/ .js+ )5mto slow down as it apk.f s +/z 9a)mytlrj5mproaches 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 direw ( 1khqib944.yff (mxrlv k0o5siz swga v25*ction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceler(svam1yf5rli w (5 kob f2wixszg40.h4kqv *9ation.

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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 mgjr 6 t8xe /6zrpd7f,koving with a constant velocity. Make a statement concerning/86jr 7t 6p ,zregfdxk its acceleration.

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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, doesl1tp- d-dyif4 it mean that the acceleration is zero? Support you1yd4l-it p-d fr answer with an example.

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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 accele/*t:d/ahv /u. twaytpd1kxn v-:f de9ration is constant? Support your answer with :d1.dv x ant -yevd:th/p fa/ twk/u*9an 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 constant acceleration. l*prsouvjpr.4+qgf 3z h(6 r3-njgw5 Make a statement concerning in+r4uvp-r(gjq3.3gsfhwor zpl * j65ts motion with 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 speq7mud ) tdrk a.ok-vf(s+8s g.ed while its acceleration is decreasing? Support your answer with an .avf8kst 7ou)k+r mdqs g -d.(example.

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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 hill of ice b19tvwh(rj:vies.at:f/ 4ra . Make a statemrt/1.ew: (sbvvh4aajt r:f9ient concerning 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 equal to the average )gdoecbap -48 of the object's initial and final veloci ga) -4bcp8doety?

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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 y+aif;)z + f /ipjo)ymstart at rest. They both accelerate at the same rate. However, object A accelerates fa;f+) /yiz ojifmp+ )yor 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. :0;4utxx 33 jm3te vni)aonbd They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by o0xn eu4)33m;oatnxjd: iv3b tbject A compared to 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 release2cv b/*w. 8retzpsq6td from rest and falls in the absence of friction, which of the f/ rpzw qv*ct2.6tb8 esollowing is true concerning 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 from rest and falls in the absence of friction, whis qf2 u.e60bwzchbu q60ewzs.2 f of the following is true concerning 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 straight up. Make a statementnb(lj03 *+o a7g wgcuub(krj wk1l*ojr):.qj about the velocity and the acceleration when the ball reaches the highest pointjk 17 ro(kq*u) 3 jgubj* rn .g+lwb0ol(cawj:.

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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 up. What is its acceleration just before id*5 t6/ew 4djab/l2buw5 qjp+2e nwdot reaches its highestqd 2 b2 jee65tdwun oj/d5wa/pl*4b +w 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 b.p4*-cm ufhs f87yroa maximum height, then falls to its initial height. Make a statement about the direction of the vys4b c rohu.7*fm f8p-elocity 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 max1o*trd :f8s ih6xn) 3h :vdimp0ne;goimum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is comnd0gomin ;6hie )hs d:x3*vtr8f:1p oing 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 thrown downward in the w;ct bp:r9 vb/y*-genabsence of air resistance. Make a statement concerning its:py; b9 n*vr b/t-egwc 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 jumq + gd)xzhw 1phrny;01a0f/+cwbh fubx0aj 99ps from a high-flying plane. What is her acceleration when she she reacf+9g1 1j /cp0zbxb;ay hh) aw rwx0f+qudh0n9hes terminal 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 ident;y 497 qwf ky9azl)drsical 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 ddsar7q l9wz)y9 4;fkyoes the second 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 bui,xvx( :vjf9z +0h dkpclding. One second later, ball B is dropped from the same bui ,k+v(vxh :09 pfxcjzdlding. 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 nv)vv bo56hm)r6c+ayf i db5.a building. One second later, ball B is dropped from the same building. As time progresses, the difference in thei. ndb5i v)v6)c5ro+ 6hym bfavr 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 building. One /uq- vvsl7y kn5xxb30is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the street5 n/qkx 0lbyv- v7xu3s?

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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 building. A second brick is thrown gp 8ji9u.fs;4 zujbl( straight down from the same building. They are released at the same time. Neglect air resistance. Compare the pg4(f zului .;89sbjjaccelerations of the two bricks.

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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 cont ,(lf1go6ix lstant non-zero velocity in the +x axis. The position versus time graph of this objectl1xgto6fli (, 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 with constant non-zero acceleration in the h7ewddz e4)p p/4yv6k)va1g 42 qxmvi+x axis. The positiod hwk)e4i1p vxpy4ge7q4v/am)v6d2 z n versus time graph of this object 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 non-zero vd u-ul6ok: izvqjsou,k 2g3*4x+j7mr elocity in the +x axis. The velocity versus time graph of this object iss ojj 2u okgdx67:-u,m3ikl*4uz+rqv

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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 w0e;fdbj,qkk fo j p(mz+/* 8:ggsf6 hiith constant non-zero acceleration in the +x axis. The velocity versus time graph of this o*: 6f k8;m+(,o i jbzspegdkjfqfgh0/bject 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 versus time graph g6p78er egp3 /uf r0fngives

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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 graph gkc pgo5i)v)a-r6kf7ot:dd *2rg- f c7jd n3vgives

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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 acceler-b t+ tw,g8mttgoq;z s 0 (3dgpsq7j9tation 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 tz -(g+bieh71 dbpuss,ime graph gives

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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 horizontal line, the o7qhqo5nb8i guh4;w) v*7elz vbject isiq8weuz5*h;4 blv 7gh)onvq 7

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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 an object is a vertical l b:2ex p7rudi)ine, the object isxip:b)u2r e 7d

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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 30+bbhqno ;ws+y )azmoh(kx1an object is a horizontal line, the object ;wxm+3 b)s0oqo(nykbhh +1azis

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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 versuse5j9fg6c,s 5mm udjx/)t5yg m 9p:uel time graph of an object is a straight line making an angle of 30 degrees with the titlm 5p cu f5x,)gmy s5u6m/jej e:99gdme 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 north and then 11.0 m south. kt7qwf:l+t/36goglcajli -ooaw9 26 Find both the distance traveled and the magnja6gwqal ckf-ot :/l+to7wo692gl i3 itude 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. 1o p*yne*j zesd6;mm zx37h pqw7i/i+ How long will it take to move 12 km upstrea+6i z7* wd3eomiehxm /yqn* p;jp1 7szm in a river flowing 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 = q pdz+o1 25hbuw:jlqb:p7;su1609 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 in order to tra m31 5z :m orepeh:nc*da 7oe*:thapf8;qx*ly vel 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 mara p 266bm;7m2y )re*wbnap; ea7l iyrqpthon (approximately 42.0 km) in 2 hours and 57 min. What is the average spee) 7abmw;al2b6em7yqer2ip p r6* n ;ypd 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. * ta8me(3v 7yexyz9ogHow long does it take for it to 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 yep; 7j83)tx om-b df z0uskc(ycar. The speed of oydf)0;(xcsz cubtp8j3k -m7 light 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 stragl)rzv nr6kd w7i(b9i+h+:a:u7qnh o ight road and you look to the side for 4.0 s, how far do you travel during this inattentive k)::ra l9gq7don hh n7+r +b(w6iizuvperiod?

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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 around an outd (ynx vvl,f1lv:wap6s;rp81poor track (400 m), in 100 s, your average veloc v 6yw ;sxv :1p,nlp1ra(pv8lfity is

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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 travg/n n3iss1r5qo;zjq- els 1.0 km south, then 1.0 km east, then 1.r- 13sg q5ijnsz/qon ;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 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 tha-h3bow jta 9;e North Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point h-;b93twa oja. 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 m3qz hk,xz-n id 063duz+j isb2i/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home after drivinz6siqx+-zz dji2d3 3 k uh0bn,g 4 hours and 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 at 100 pkj8-/0rcazh,p6u s b km/h. What is the average s6/,8kzuahjb p0 c-rpspeed 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 forunvq w713cdm. 7,x -qak/ aobn 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her average speed for thexubdn.nk7- w 3qmaa/7v, 1coq 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 kkp0oqudwn.e5(( :1fhig0 bfsouth for 2.00 h and then at 250 mi/h north for 750 miles. What qfk(.0(o 0n we: h5difkb1pgu 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 person who runs the last 100 m) forn7 73q 9j/uwyh9jg4aj;zlpi s 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 team B runner can have when the team A runner starts the final leg of the race, i3q7;uzyj 4gwhi9 s napl/9jj7n 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 comes to a stop aftkul w.ujej.c26 rsbo 64 3k1mser 11 s. The car's average velocity during deceleration was 55 km/h. What was the car'sjr1u..k2wmb3kj ls4e6suco6 deceleration while 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 average rat qvqz)-fk vx:7e of v qzvfk)-:7qx$15 \; m/s^2$. 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 ray pna)/hy:it8otqs7:te of $2.0 \; m/s^2$. 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 and accelqr ycr nj +;2olq.v :s)x4xz4herates 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 foymf //265ws ncxly8pb r 10 s. It then speeds up with a constant acceleration6 2 pl/fcbyyx8/5wnms of $2.0 \; m/s^2$ 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 initial velocity of 5.6 m/s experiences a confdlrbjv 42*i7 stant acceleration of*jdv2 rlbfi 47 $4.5 \; m/s^2$. What is the cart's displacement during the first 7.2 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 the right (+x di.qw mnzia3 2en8-4;mowpe cy* rection) with a speed of 225 m/s strikes a sandbag and penetrates a distance of 94.99 cm. What is the average acceleration, inm*w2oni;zp.aw4e3n emc y8 q- $m/s^2$, 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 aircraft carrier. d)vslscn 16*0nilq .b It reaches a speed of 42 m/s at thedb1l v 0)lni*cns.sq6 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 with constant 9v,aqzi tc+ p7h/li pfz8 )lh/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 it0 k 9)mlulszt-s average accelerat9tsl lm0kz-u)ion?

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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 undmpmnv:), hyqv f)/*gz ergoes uniform acceleration. During the first seconq)/m g,h v)p:*mnyvzf d it travels 9.9 m. How far will it travel during the third second?

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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 with constant acceleration. Initiallyt-* c. eva2btv it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/tt bveav.*-c 2s. 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 rest and accelerates uniforjps;2d3sb o n-mly 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 on a dry road can decelerah:p-*;sa ike;xrq-eaijl f +3 te 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 orcx*.,yv 6kecar that has been waiting at the inter,6 cv yre*kx.osection starts ahead with a constant acceleration 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 sp:37vzv xbbexmt 487;c rl1y2bm qvs.feed of 12 m/s on the surface of planet X where the acceleration due to grav 83;x2vm cve4rbszmf:.17 vq7 xybtblity 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 thmp,* *6rvl mm cvawo9,5s xtm9e surface of planet X where the acceleration due toml 9m,5p*wv6 t 9vscomx*am,r gravity 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 o;d 6c,qxm4ox xn the surface of planet X where the acceleratioxxc4 6m ,q;oxdn 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 on the surface of planet X whd99cye lmipl m- zv f),/f ncsp:553lrere the acceleration due to df,rvzi/:ml)lcpc s m 9yn39p5fl-5 egravity 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 grea uyxr8 gu4m2;oter than 0.10 s. If your friend holds a ruler between your fingers and relu8;o gx4y2r mueases it without warning, how far can you expect the ruler 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 a velocity of 19.6 m/s. What is itsxt wkuc7l)p3mg0cw4 6 4dz 9gb velocity after 3.0 6kmw4 )xg7 9uzd04wccgtbl3p 0 s?

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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 61i0c y0xzqpp:adcu6 returns to its starting point in 13 s. What is the initial speed of the 0x 661zai qp:cd0upyc 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 long does it take tofk 7e t83cqs(pk9 y8)usz3;2jt yk ,rdo*k lme return to its starting pointel pfs2,oje*s3tk988) u cm dqk7zk;3ytyrk(?

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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 of a building with an initn97r1j/n :v4mvxnnqd ial speed of 22 m/s. 9nnn17drqvm vj4:/nxIt strikes the ground after 7.3 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 with a speed of 30 m/s. (only fill nt5tnzd81 3-nj-awy qin numerical value jqw d a5-nz 1n8tynt-3in 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 st*dlw uy h-lhm1o7tz88,q0bsbraight up into the air with a speed of 38.9 m/s. (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 1 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 atac3er 02 yvdl7 t = 1.0 s?


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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 .7 h,.ccyagipis 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 vv6nf:o st.-wzy po xu5udt0 0/elocity 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 velocity at t = 5xpbg;i,)bof zpo cqgi (5w,8) .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 fr 2usccnlxv0c9jdq:8 x :68s ddom 0 to 4.0 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 t9tta i4 / z+dkzywy1 +fz2anqw-/g6uto 6.0 s?


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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 acceler :,j( )f3wz +ydjdsmlu5zt,mqek ,6d ration 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 acceleration at 3.0.xqztoeiu2s d h m7m)o / qz)j),:lw8f 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 auuj91.kdzqiy hf,d /r vgj )3.verage acceleration from 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 the average acceleixoct+z 6w+xzu8e 1k;ration 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 f 9uy5dw h4yr0i(s5vmam j l)zv4m: ;eorom 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, j (sfvz9 y-:jbvelocity? {speed|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 jqsgk)k9( qj2fb1t :qvelocity 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 po59oz dskxk+ ksy/d8u*sitive.

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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 first musgj02yhb) a0diq ,)s gqt have a grea )gbg0 ia0 s)q2dhqyj,ter acceleration.

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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 by side from a tunn 21q z g3d/mdwu /pu ,5hgq*13ds)s+dekzwyrcel. 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 acceleration decreases.l7 8l*dg74)l evbmkut

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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 into the air. It wg(mbu8 bcx.v8p nu*,leaves the bat with a speedv(up.mb8xc w,g8u *bn of $120 \; km/h$. 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, h /x8e pt ;xlk ;-0putyp997mavvelq:pow does pe9tpv7 lpp y9exxt8mq v0l; :a;uk -/it change if air friction is ignored?

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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 object speeds up, what is happening to its acceleratios.e 6:z if ;q1a vafhyvaf;51pn, how does it change if air qhav6 yz1p ;f1s5 a:;.iaeffvfriction CAN NOT be ignored?

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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 upward will return to its original d1u csxim 9;ggamb: n7k6bz9n1 tzv 90position with the same speed z ig1nct0a v9u ; 6x7bz:mg1mdk9n9sbas 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 at the same tgc*ccs 7km0qlu 9y(s* ime.

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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 nonzero velocitn)j2p) jt e. hg0euzn0hpr87v y 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 the second floor to the fifth floor z k/kr - vc.sv8r//rsylijv99making no stops along the way has zero acceleration all the time.8 /.zss ly- rrc9rv/i9vkkv/j

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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 moves7l* k8nq1 i/m mzhoc kiqs1* :5kfv9fd from $x_1=1.7 \mathrm{~cm}$ to $x_2=-8.4 \mathrm{~cm}$ during the time from $t_1=2.1 \mathrm{~s}$ to $t_2=6.0 \mathrm{~s}$. 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 $t_1=-4.0 \mathrm{~s}$ is at $x_1=3.2 \mathrm{~cm}$ and at $t_2=3.8 \mathrm{~s}$ is at $x_2=7.7 \mathrm{~cm}$. 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 rjarbt 09k0uu+n ./a raround a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 12.0 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 straignzjdm,v4q*g: 1tp+gl ht line, moving 98 m away in 11.2 s. It then turns abruptly and gl +d4,mqg :j1tn* vzpgallops 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 frog,7+y/d d seakm $12 \; m/s$ to $23 \; m/s$ in 5.9 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 from p)qem3q wgo gq5af(ox.i819 v$17 \; m/s$ to rest in a distance of 57 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 c+,/cbblxsz2 90ntoxko la-(ed of $33 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.5 \; m/s^2$ ?  (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 the blocks to essentially top spcqounw8ye, b1;7s h.2hm4 j dgeed abou;hmbuy 4qdw1h enjgc8 s27o ,.t $11.1 \; m/s$ in the first 12.8 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 uniformly frnjpl7u-7q-yo s4: fli om a speed of $19 \; m/s$ to rest in 4.10 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 skid marks 92 m long on the highway. +tiaid;c.p ogg7a j 10Assuming a deceleration of ia ojad7i +01 pg.g;tc$7.00 \; m/s^2$, 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 truck going11c t;/apd z(f / 5 rii)gptiz2fkm)ge $25 \; m/s$ 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 complete the 10,000-m run in less than 30.0 min. Aftebm pht1j(,w *x rn*vr/r exactly 27.0 min, there are st/mrv*xrh,jbw 1(n tp*ill 1100 m to go. The runner must then accelerate 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 hits the ground belowg zo 2v;:0m7kzfyu0a2oy iiq3 after $1.54 \; s$. 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 itbxm r;xkm0,bvj1u w/1 took a stone to fall straight down from the top of the Empire State Buildi;jukb,xv rm1 10 wbx/mng (365 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*hv m z;ia0a/+g1f uhx with a speed of $22 \; m/s$. (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 ball 2.2 s after throwing it vertically upward. (a) Withl*-s4)f:g xobjg,gsw3u, s a m what speed did he throw it? s j ufgb xm)lsg-as3, *,og4:w (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 verticnp-5wu)egjp0 +m rr)dally with a speed of $5.07 \; m/s$. At a height of 92 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 ssxj72j)vi( h n /deyg,peed of $16 \; m/s$. (a) How fast is it moving when it reaches a height of 8.0 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 0.22 s to travel paq xe+d1*+z.idly,lvd st a window 1.5 m tall. From what height above the top of the window did the 1x+ezdlv ,y+iq*d dl. 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 igf* (i4;q svif xj2vq(t striking the ocean is heard 2.4 s later. If the sp2 jgqvf(*q 4s(vi xif;eed 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 verticall qn5ozf)b ;)zbhr+9mfy upward with a speed of $9 \; m/s$ from the edge of a cliff 56.8 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 by someone on the 9th floor (28 m abob l 8y4gzvny65 f*sek1ve the street) with a vertical vklfsy*1g4 z8 en 6yb5speed 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 gravity on the Moon is about o*wck;m,evz: one-sixth what it is on Earth. If an objectwoc,zk*em ;:v is thrown vertically upward on the Moon, how many times higher will it go than it would 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 trai6w2o* uqe7ctmn has a spe equ6*tw 7moc2ed of $24 \; m/s$ when it passes a railway worker who is standing 149 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 a constantc(ewktzw wrd:(3 o18wzq8vs v90,c jd 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 fro 9(lg*h+uqj1ou sqpq: m the roof of a high building. A second stone is dropped 1.40 s lat+s p q9uq:*lqg(houj 1er. How far apart are the stones when the second one has reached a speed of $11 \; m/s$?  (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 must a)7mkyv s h.4;yf( ketx+9 qaneverage $200 \; km/h$ over the course of a time trial lasting ten laps. If the first nine laps were done at $195 \; km/h$, 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 resb--figts0v y0z+- arbt, with an acceleration 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 buildiik -dyh9w 3cu/b(nzw y*ns.m, ng; 1.77 s after that, a second stone is tc,k -9sd(3. /yw byunwm*iznhhrown straight 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 ref49rczv;opb kv 4 ew .2zz8lq8sistance, how long would it take a free-falling parachutist to fall from a plane at 3330 m to an altitude of 35z8 zz fokvbr;l p 8c44v2q9ew.0 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 ball7p;-ndb:i nr z(aqna8 vertically at a speed 1.4 times faster than Joe can. How many times higher will Bill’s ballzn;n n -bqdr 7pa(:ai8 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 frienr f19tykdmc.7x-gn3 68f mwau d stands on the ground below you. You drop a ball from gnuy cdf69w-7 m8k.xma r31 ftrest and see that it takes 1.2 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 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 find the height o nrfi. u,)dwm98g )v5rt;v5pqiz ds y4f 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, af.;pm ) 9)vdviwnir54, dz8syr5utq gnd the other, 2.2 s. How much difference does the difference in time make for the estimates of the building’s height?  (数值)  $m$

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