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习题练习:Physics Unit3: Kiematics Motion in Two Dimension & Vectors



 作者: admin   总分: 71分  得分: _____________

答题人: 匿名未登录  开始时间: 22年07月20日 00:48  切换到: 整卷模式

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1#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which one of the followiu/mendaji1 kct;-d5qn2 pe ) ,ng is an example of a vector quantity?

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2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following op/t 3l9n27 ze;y. al5uxpztvkzerations will not change a vector?

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3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following is+8ak50 r nm)(lq qs3p fbbw-ke an accurate statement?

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4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resultant of two vectors is the sman -pkb1:xpmiotm(k//j 90qzo 9r9zph llest when the angle between them is

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5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two displacement vectors have magnitu.e(p u+lqgieg30y xlch 5js0 1des of 5.0 m and 7.0 m, respectively. When these two vectors are added, the magnitude ou e.l(0i hpl 01qgs xec5gy3+jf the sum

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6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two vectors, of magnitudes 20 and 50, are added. Which one yute* 6m ;3pqj e3k9lxof the following is a possible answer for the magnikp6eutl*emx jq3;9y3 tude of the resultant?

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7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three forces, each having a magnitude of 30 N, pull6;k f vbr ;qx(fx -+m2(bhytfk on an object in directions that (f+ br2;v;y bkh6 (x-txmkffqare $120^{\circ}$ apart from each other. Make a statement concerning the resultant force.

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8#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In the diagram shownsn a ro/qm0jx u:gn,:;, the unknown vector is


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9#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Ignoring air resistance, the horizontala)guwb0qa;7mzxoj df5 94(b2 cv lr9u component of a projectile's velocity

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10#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball is thrown with a velocity of 20 m/s at an anfyx. *;uz)vustix5 h(7xsuw.p7fz-e gle of $60^{\circ}$ above the horizontal. What is the horizontal component of its instantaneous velocity at the exact top of its trajectory?

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11#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Ignoring air resistance, the horizontal component of a proki9z ip3cr d6 y))vgv;g vd q*+(3huncjectile's accelerationc6n3py)+(gvdrvgcd3qi *hi)uz 9 vk ;

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12#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A soccer ball is kicked with a velocity--q cziaut,;y p:lh.f of 25 m/s at an angle of $45^{\circ}$ above the horizontal. What is the vertical component of its acceleration as it travels along its trajectory?

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13#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the acceleration vector of )l cg buhuiq0+ aw4z4l v6.e2wan object is directed anti-parallel to the velocity vecto4l. lv40qwa b wuiz+62ecuh)g r,

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14#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the acceleration of an object is a48: lvime;jqr ns:)lhlways directed perpendicular to its velocity,lhnjl 4;vs:qi8rm :)e

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15#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what angle should 01b/4wru -x0-heoitrn.qd cd a water-gun be aimed in order for the water to land with the greatest horizontal .tn0c i-/0qob r-r1xwddeh4urange?

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16#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An Olympic athlete throws a javelin at four different angles above the horizlf+ l v)rytzyt 9 bq6+0h3.9 /vlxf;yz(zhdqg ontatvqyq)dhll9gfb/frh3+ 9yvz ty;l0 z +6.x ( zl, each with the same speed: $30^{\circ}$, $40^{\circ}$, $60^{\circ}$, and $80^{\circ}$. Which two throws cause the traveling to land the same distance away?

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17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are throwing a ball for the second time. If the ball leaves your snzqg 08o937hy*eyel hand with twice the velocity it h79 *y0l8egsznye oh 3qad on your first throw, its horizontal range R (compared to your first serve) would be

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18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball is thrown at an original sp,iw *(d;rpejlbkg 62 .e(jrlom6 nd,feed of 8.0 m/s at an angle of $35^{\circ}$ above the horizontal. What is the speed of the ball when it returns to the same horizontal level?

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19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  When a football in a field goal attivdxjly .88zo+49u 3o3w tnazempt reaches its maximum height, how does its speed comparea3 8ixt z4v3.n8u+ ojoyz9lwd to its initial speed?

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20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A stone is thrown horizontally from the top of a tower at the same insta rvl)/efvmrv: 6xzs :,lyc:c;ib 31lf nt a ball is dropped vertically. Which lylf x r),mz6s c1v il:cvr;v3:bfe/: object is traveling faster when it hits the level ground below?

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21#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A bullet is fired horizontally, and at the sam(soux (zct sg.4(i*vx qij:-ae instant a second bullet is dropped from the same height. Ignoi-g :*uzq4issx. (xcovj((at re air resistance. Compare the times of fall of the two bullets.

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22#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A plane flying horizontally at a speed of 52.6 m/s a c429td hw5afrnd at an elevation of 182 m drops a package. 3.9 seconds later it drops a second package. How fa5d94ch atrf2wr apart will the two packages land on the ground?

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23#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A package of supplies is dropped from a plane, and one sd6+e ts ja)0j7jceld7-gd 0z xecond later a second package is dropped. Neglecting air resistance, the distance between the falling packages e std6j 0+xd 70jed)lga-cjz7will

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24#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A pilot drops a bomb from a plane flying horizontally at a constant w;66nxfqxfx (, r4vv gspeed. Neglecting air resistance, when the bomb hits the ground the horizontal g 6q;nxvx(4 ffv6rwx,location of the plane will

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25#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The acceleration of gravity on the Moon is only one-sixth of that on Earth. Ifah 64c1lv6nff you hit a baseball on the Moon with the same effort (and at the speevn66h14 claf fd and angle) that you would on Earth, the ball would land

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26#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are traveling at 55 mi/h in the +x axis relative to a strh-5hhczq.2 4mli ig/53aksud aight, level road and pass a car traveli q hs-/4 gm2 dzul.c5aihh3k5ing at 45 mi/h. The relative velocity of your car to the other car is

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27#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are trying to cross a river that flows due south with a strong curreqtkdete e7 pnyerq5 f (4-9nw2n3r .z;nt. You start out in your motorboat on the east bank desnwtqe ez e(fr.dn2nrtky-e3p5 794 q;iring to reach the west bank directly west from your starting point. You should head your motorboat

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28#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Your motorboat can move at 30 km/h in still water. How muchad pdk 5h4b1dn0trr73 time will it take you to move 12 km downstream, in a river flowin7 d0rkhda n1 4d5r3tpbg at 6.0 km/h?

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29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Vector A has magnitude 8.0 m at an angle of 30 degrees bew 7 i16w: z,awyrbguj 6-i8uf sob7g7z65gn ptlow the +x axis. The y compon aw sw7if-867ot67bu rpg5ibugynjzw:z6,1 gent of A is

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30#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a ball is thrown with a velocity of 25-*pd 6 07 :uci),sm jlkwnbzlr:cvt: k m/s at an angle of $37^{\circ}$ above the horizontal, what is the vertical component of the velocity?

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31#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If you walk 6.0 km in a straight lin/ ctx stm/-c)l4 fc3cw lwmy/1e in a direction north of east and you end up 2.0 km north and sevec)l/w c/3wyx c c4f-1tm/tmslral kilometers east. How many degrees north of east have you walked?

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32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A butterfly moves with a speed of 12.0 m/s. The x component of its velocity 6lh44wtg;tiyd0b/:pf rru gvis/ 51d x25qgr is 8.00 m/s. The angle between the direction 6:p dr i2r vtwlygiuq1ds4xr0b t;ghfg/5/5 4of its motion and the x axis must be

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33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 400-m tall tower casts a 600-m long shse;y t q :3puv,wnx*)cadow over a level ground. At what angle is thw)ep;x:t*c 3yvnq s,ue Sun elevated above the horizon?

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34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two vectors A and B have components (0, 1) and (-z;zd(2on6 bj.hx/1sma 7kex n 1, 3), respectively. What are the cn1k7xhs6./;a zo(dxn zb2e jm omponents of the sum of these two vectors?

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35#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two vectors A and B have components (0, 1) and (-1, 3),a;1+tebh6- ,l 9yhe v qsmym5q respectively. What is magnitude of the sum of these t1+eme5-y ahqlmvq ,tsh b9y;6wo vectors?

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36#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Vector A = (1, 3). Vector B = (3, 0).+ahb5wt5 vh x-, wrwf0 Vector C = A + B . What is the magnitude of C ?rb 0 f-htww5xwa5+,h v

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37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A car travels 20 km West, then 20 km Sarf5fsh4h *2 south. What is the magnitude of its displaceh h5saffr*2 s4ment?

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38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three vectors, expressed in Cartes +hp7bh2uwq8b w/s6i qx8a zc(ian coordinates, are
S = (-3.5,+4.5)
T = (0,-6.5)
U = (+5.5,-2.5)
What is the magnitude of the resultant vector S + T + U ?

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39#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three vectors, expressed in Cartesian coordinates, 1sx+x l3q5 7h a1ftwiuare
S = (-3.5,+4.5)
T = (0,-6.5)
U = (+5.5,-2.5)
What is the angle of the resultant vector S + T + U measured from the positive x axis?

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40#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If vector A = (-3.0, -4.0) awakt.gfxb;8- nd vector B = (+3.0, -8.0), what is the magnitude of vector C = A - B ?w-tgfab.; xk8

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41#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A runner runs halfway around a circular path of radius 10 m. W*qumam p7b*gc.ulo 4rwq(w,;hat is the displacement of the jog(l quu cpo.a;ww47 qr*mgbm,*ger?

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42#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two forces are acting on an object as shown in Fig. below. hphh8gblcc m m9w4 ;09What is the magnitude of the wmhhg0bcmc;h84l9 p9resultant force?


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43#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two forces are acting on an object as s4atcoex z(6l.4q f-pbhown in Fig. below. What is the direction of the resultant force.-z a46e(l4c tqobxfp?


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44#
 
填空题 ( 2.0 分) 切至整卷模式 搜藏此题  
  Vector A is 5.5 cm long and6b,go j--p0:zrh: xzvnekz1 z points along the positive x axis. Vector B is 7.6 cm kgz zzor10 j -xv-:6ehpb ,nz:long and points at $+22^{\circ}$ to the negative x axis.
(a) Determine the x component of Vector A $A_x =$ (数值)  $cm$ and y component of Vector A $A_y =$ (数值)  $cm$
(b) Determine the x component of Vector B $B_x =$ (数值)  $cm$ and y component of Vector B $B_y =$ (数值)  $cm$
(c) Determine the sum of these two vectors in terms of components. $R_x=$  (数值)  $cm$ and $R_y=$  (数值)  $cm$
(d) Determine the sum of these two vectors in terms of magnitude  (数值)  $cm$ and the tangent value of the direction angle (measured from the posive x axis rotated in the counterclock wise direction) $\tan \theta = $  (数值) 
Please only fill in numerical values in the above blanks!

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45#
 
填空题 ( 2.0 分) 切至整卷模式 搜藏此题  
  Vector A is 67 cm long and pi7msmcc,ope6;8+ yz 8v0 gwzeoints at $30^{\circ}$ above the positive x axis. Vector B is 18 cm long
and points along the negative x axis. Vector C is 46 cm long and points at $45^{\circ}$ below the negative x axis.
(a) Determine the x and y components of Vector A: $A_x=$  (数值)  $cm$ and $A_y=$  (数值)  $cm$
(b) Determine the x and y components of Vector B: $B_x=$  (数值)  $cm$ and $B_y=$  (数值)  $cm$
(c) Determine the x and y components of Vector C: $C_x=$  (数值)  $cm$ and $C_y=$  (数值)  $cm$
(d) Determine the sum of these three vectors in terms of components. $R_x=$  (数值)  $cm$ and $R_y=$  (数值)  $cm$
(e) Determine the sum of these three vectors in terms of magnitude  (数值)  $cm$ and the tangent value of the direction angle (measured from the positive x-axis rotated in the counterclock wise direction) $\tan \theta=$  (数值) 
(Please only fill in numerical value in the above blanks!)

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46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A stone is thrown horizontally with an initial s3zlc:egbu7z g./xi h4pf:uz /peed of 25 m/s from the edge of ./z34bu/: ggluzpi cef7 :hz xa cliff. A stop watch measures the stone's trajectory time from the top of the cliff to the bottom to be 2.3 s. What is the height of the cliff?

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47#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A girl throws a rock horizontally, with a velocity of 5 m/s, from a bridgeb1if85wknryp )03wkr( c 2.uskmi7z h. It falls 22 m to the water below. How far does the rock travel horizontally be0my5i. u3rrwk zk(1 w)pknc87hbf is2fore striking the water?

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48#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball thrown horizontally from a point 20 m above thn,f g2zj1n6gde ground, strikes the ground afterj1g nz 6d2,fgn traveling horizontally a distance of 22 m. With what speed was it thrown?

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49#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A jumper in the long-jump goes into the jump with a speed of 12 oj8(3aexflz1c* gz2 5 fxhwi f2s0;j;ykjr 8gm/s at an angle ow8j3jr2;1c 5( 2l0x hgxkfi;* fjzs oyefzg8af $20^{\circ}$ above the horizontal. How long is the jumper in the air before returning to the Earth?

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50#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A jumper in the long-jump goes into the jump w h ns76*4barfdx d:kg/ith a speed of 13 m/s at an angle of kf4 b 6:7d sgd/rx*anh$29^{\circ}$ above the horizontal. How far does the jumper jump?

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51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A projectile is launched with an initial velocitwo7q7s )6m8jg4ipnjvn :nw- ry of 53.0 m/s at an angle of $16.0^{\circ}$ above the horizontal. How far does it travel?

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52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A projectile is launched with -9ecf hy 0mx/;obq o9gan initial velocity of 42.6 m/s at an angle of $37.8^{\circ}$ above the horizontal. What is the maximum height reached by the projectile?

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53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A rifle bullet is fired at an a hukrd ):h )jcb6jl+.qngle of $30^{\circ}$ below the horizontal with an initial velocity of 800 m/s from the top of a cliff 80 m high. How far from the base of the cliff does it strike the level ground below?

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54#
 
填空题 ( 2.0 分) 切至整卷模式 搜藏此题  
  A projectile is shot horizontl/(8 tf / ck)(ibdt a5ki*assoally at 24.1 $m/s$ from the roof of a building 54.5 $m$ tall.
(a) Determine the time necessary for the projectile to reach the ground below.  (数值)  $s$
(b) Determine the distance from the base of the building that the projectile lands.  (数值)  $m$
(c) Determine the horizontal component of the velocity just before the projectile reaches the ground.  (数值)  $m/s$
(d) Determine the vertical component of the velocity just before the projectile reaches the ground.  (数值)  $m/s$

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55#
 
填空题 ( 3.0 分) 切至整卷模式 搜藏此题  
  A projectile is fired from ground levj 5g2ishuia, e8s 8w7/k :jnnqel with an initial speed of 40.2 m/s at an angl8 k 5sjii2e:nw,8a7h /sgjuqne of $38.7^{\circ}$ above the horizontal.
(a) Determine the time necessary for the projectile to reach its maximum height.  (数值)  $s$
(b) Determine the maximum height reached by the projectile.  (数值)  $m$
(c) Determine the horizontal and vertical components of the velocity vector at the maximum height. horizontal:  (数值)  $m/s$ vertical:  (数值)  $m/s$
(d) Determine the horizontal and vertical components of the acceleration vector at the maximum height. horizontal:  (数值)  $m/s^2$ vertical:  (数值)  $m/s^2$

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56#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  On a calm day (no wind), you can run a 1500-m race at a velocity of 4.0 kn94iaj:l u9pmepofow 02 z;r-pq84g pt/ z/mm/s. If you ran the same race on a day when you had a constant headwind which slows your speed by 2.0 m/s, the time 8 om-p94apfi rq ;2:j/eznwm4 p9t gl0z uo/pkit would take you to finish would be

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57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A plane has an air speed of 200 m/s d4(usdp4jow dg1p -3fqk7 fe*4qmytvo-54 ytoue North, and is in a wind of 50.0 m/s to the West. The plane's speed relative to the ground 3yst t4(e4ooqj4 7p qfwmdpfuo-5 -yg1d4v k* is

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58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A plane is flying due Southb8j ziu)t f8h4n3.jsmly(yu;xxwen n+ ((hb9 ($270^{\circ}$) at 500 km/h. A wind blows from East to West ($180^{\circ}$) at 45.0 km/h. Find the plane's velocity with respect to the ground.

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59#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An airplane with a speed of 120 km/h is hea;d+h , fv+sd zmlxpgix . .k-d.(0zsmzded $30.0^{\circ}$ east of north in a wind blowing due west at 30.0 km/h. What is the speed of the plane relative to the ground?

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60#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A fighter plane moving 200 j3p7e eh dx+cr0 .dxtbqc/-m8m/s horizontally fires a projectile with speed 50.0 m/s in a forwarx-t+bx0.deqhc 7cp/ 83 mdjr ed direction $30.0^{\circ}$ below the horizontal. What is the speed of the projectile with respect to a stationary observer on the ground?

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61#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A boat, whose speed inb(ls0 8i0 p9 mgienn)s still water is 8.0 m/s, is directed across a river with a current of 6.0 m/s. What is the speed of the boat as it cipi 8mbs0nls(n 9) eg0rosses the river?

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62#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The driver of a motorboat that can move at 14:5cecu9gs en/ptx7 . k m/s in still water wishes to travel directly across a river 0.9 km wide in which the current f.7sntc:uxek9e c 5gp /lows at 3.9 m/s. How long will it take to cross the river?

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63#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The driver of a motorboat that ca,wx (v6p/t9an c +zc -nr uqzs3+yrh0xn move at 10 m/s in still water wishes to travel directly across a narrow strait in which the current flows at 5.0 m/s. At what angle upstream( -/v6z0wn+hczt,x u+rs9n3xq pyr ca should the driver head the boat?

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64#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A swimmer heading directly across a river 200 m wide uqazh94 f(.e7ups fe4reaches the opposite bank in 6 min 40 s. She is swept downstream 480 m. How fast can she4f(9ep hqf4aueuz7.s swim in still water?

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65#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A swimmer heading directly across a rijyz5ckl7 j fuz 8(:mn0ver 200 m wide reaches the opposite bank in 6 min 40 s. She is swept downstream 480 m. What is the speed of the currelj 0 f7kc5nu(zzy8m:jnt?

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66#
 
填空题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A boat, whose speed in still water is 1.72 m/s, m2ubm 16p.(t m d/rhjijc1 7dsaust aim upstream at an angle of121 j6(rjpc/isbm7hdau td .m $24.5^{\circ}$ (with respect to a line perpendicular to the shore) in order to travel directly across the stream.
(a) Determine the speed of the current.  (数值)  $m/s$
(b) Determine the resultant speed of the boat with respect to the shore  (数值)  $m/s$

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