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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 follli (44/qz h)y- 4gk2fqqjgdpmowing 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 oper.,6h vqer-jgrations 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 an a ze-vgcm7; g5tccurate 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 smallestnlmt x-e v fvodksd.07 ry-789 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 magnitudes of 5.0 m and 7.0 mu-ug bf 1eea*,h,*5tfio j xl*, respectively. When these two vectolu,f* atug e1f ijb- 5**eo,xhrs are added, the magnitude of 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 andf l2swe6 6lfy7 50, are added. Which one of the following is a possible answel7y6 2sfe6 fwlr for the magnitude 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, pull on an object in dir)oaw5 g v5gftyq*tt* 5 nxbu/.c vha:o *.9lojections th *yn.9attg5bq : *lxvw*av)uj5o5 fctg./ho oat are $120^{\circ}$ 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 shown, the unku16ihvzen1 3rnown 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 horizontal component of a projectile0bp;v;;rc tx3f lpin+ksv13llb- -fs '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 veles0xfetp iwkv t 31d8i9 35o/wocity of 20 m/s at an angle 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 projec7dvap w7b0ib+2 k wlw8 1nje(ctile's accelerationapb8 +w1iwl7 (2kd v0n j7ebwc

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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 o. x2 bdrr-.ie1lt:7gmp 2yf/jqv1u ljw ;ahk ,f 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 vn/ia)yd 8/if dector of an object is directed anti-parallel to the velocityd8y /i an)/ifd vector,

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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 aj1b *nwa1wpb4 rmt21: ikjo, sn object is always directed perpendicular to its velocity:i,mj1rob b24wpnj 1* 1s tawk,

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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 a water jr9h+det xx5w,6kj:p-gun be aimed in order for the water to land with the greatest hor:+,p dxkxwj596 hejrtizontal range?

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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 horizon7m1 qpd v1o;8q,xulh xtal, each with the same speed:hq;lmu71 pqd 1xv, ox8 $30^{\circ}$, $40^{\circ}$, $60^{\circ}$, 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 tnywdvq) ) wmxn+0b cf64jcd1 ;he ball leaves your hand with twice the ve0q)dyfd 4x 1w c6mn;w v+b)ncjlocity it had 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 speed of 8.0 m/s at 5o ,+v lunw wmnxp1-j.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 attempt reachedoej9 ,,tah x)29kd fjw/bl uxru;88b s its maximum height, how does its speed compare to its initi8detr9,ok;2 abub/dj xw ju 89fx)lh,al 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 (m/62 vhs04k pdezhp q- 8dncsat the same instant a ball is dropped vertically. Which object is traveling faster when it hits the leshp( 8cvn p-2dq40sm6dhk z e/vel 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 ho8vwm; w b ,y(,,wiccycrizontally, and at the same instant a second bullet is dropped from the same height. Ignore air resistance. Comyc, ibwwym w;c(c,v,8 pare 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 107.8 m/s and a1uexrepy x+ub n8,j0r n--e b,t an elevation of 258 m drops a packa , 0 euruepr-yb+jxe-8n1bnx ,ge. 2.8 seconds later it drops a second package. How far 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 dro 5jjjk-4ave x4+/ibe . 7jnoe qfv,/ihpped from a plane, and one second later a second package is dropped. Neglecting air resistance, ,boj/ij 5e ji-en7jevv kfh/4xq4.a+ the distance between the falling packages will

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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 hori8ti+)rqly ez:wt5m e2zontally at a constant speed. Neglecting :ettl i)ew8m+2qyrz5air resistance, when the bomb hits the ground the horizontal 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-sixr+mrb1f+dcu 6doq si 37u /*juth of that on Earth. If you hit a baseball on the Moon with the sambu7im+d+uscrudrj*3fo 6/q1 e effort (and at the speed 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 mi6 3le*8 qqiyhs/h in the +x axis relative to a straight, level road and pass a car traveling at 45 mi/h. The relative vhqq3lsy i*86 eelocity 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 f+,jij ytmxzpj. k ,g2w0zpz4 2rfn63w lows due south with a strong current. You start fwtz py,2g.2 n x j zmk4wr60j,3+jpziout in your motorboat on the east bank desiring 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 much tim gv-ryi t+v)5je will it take you to move 12 km - r5tyg iv)vj+downstream, in a river flowing 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 a-fwwp j2 +mv6oa9/mrk.ni,xv/g k8lhn angle of 30 degrees below the +x axis. The y component of A iw m6kvflra nhg/o .x/vjpik2+m ,-89w s

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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 90rdpx.eq1 5t ilrt it 8,(lhlsfp68hm/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 line 3xe9c --0lmbjdgu+b cin a direction north of east and you end up 2.0 km north and several kilometers ea -9dbc3l0c+x ubgej- mst. 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 it u2-v a7grj*1xf k- bi.c8s+s und9pzykem)4bs velocity is 8.00 m/s. The angle between the direction of its motion and -4 9ekd. bcjsr8ixyz -muv)2 bas* +fgpnu 71kthe 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 shadqopz7xqt ib+ jpy71+ /ow over a level ground. At what angle is the Sun p/ +ijqb yt7oqp+17x zelevated 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 (-1, wi ,7 luuq/:x- oed x5n+jg82,omdacbyl)4sk3), respectively. What are the components of the sum oyul/w)+iold: es 48j, qca bkm2 5xn,d7xgo u-f 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), respectively. Whatdwr1d6p22 8yby gr*ye is magnitude yb w2g8rdy r dy26*pe1of the sum of these two 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). Vector C = A 4y/c6 abici4u + B . What is the magnitude oi 4/cyu 6ic4baf C ?

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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 South. What is the magnits eyo-7qs6 2g w4fvrsi3 not-+ude of its displacemen6qivo-gs4nw2 y+e37r sftso-t?

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38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three vectors, expressed le+oy4vfc8th ie5 z32 in Cartesian 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, expresse2n u +*p jvcx5ft35x5todb:u + a7tfimd in Cartesian coordinates, are
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) a6bf9wzd0 vp12 6zfjsmegg7o 0nd vector B = (+3.0, -8.0), what is the magnitude of vector C = A - B gzweg m29ffp6610v0zjsb d7o?

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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 r1kfjm:9wzg 2:qcu1oj2. v kk 0imqo f5adius 10 m. What is the displacement of the .:oo0mvff2 q u21ckg5 kk:qjizm 91wjjogger?

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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 x- zjd5j g-a4b9,kwbby e.kg:object as shown in Fig. below. What is the magnitude of the resultantzyd.w xa,4be -kg b 95b-:kgjj 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 shown in Fig. below. What is the directiofft.1ovjtagt- gfe6 0+f3i uqn5 rv*.-5gc aqn of the res af.u 5tf.q0 t*enqo3grj gt+cf6 i-v1fg5a -vultant force?


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44#
 
填空题 ( 2.0 分) 切至整卷模式 搜藏此题  
  Vector A is 3.5 cm long and points along the positive x ax*lth 830z m5okn9 -n, qy*suugo6wfgjis. Vector B is 7.4 cm w95uo k gsnfh*q6tol, y-3g *um zn08jlong and points at $+43^{\circ}$ 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 prk20p4f07iutcsoh ot+ l44 wgoints at $30^{\circ}$ above the positive x axis. Vector B is 21 cm long
and points along the negative x axis. Vector C is 38 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 speed of 14 m/s from the edge w8q1dwn-ihh;8 j s fx*of a cliff. A stop watch measures the stone'h w1hn-8fj ;dq wxi8*ss trajectory time from the top of the cliff to the bottom to be 3.1 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 horizontall8 h aa b7f3aarv+d.5htd 6;pipy, with a velocity of 9 m/s, from a bridge. It falls 11 m to the water below. How far does the rock travel horizondpfh8r 7h ;pib6aa5 3tad+.avtally before 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 t8q1ip4 kan7 thsh+mvnq kl ,-+he ground, strikes the ground after traveling horizontally a distance of 15 m. With what speed was it tkh7hati8++ 4vql1m,ps -kqn nhrown?

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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 m/scj 3w m;f+enj+ c)buc6*mr(u v at an angle cu bf*erm3j c +jc6w(+vn)m ;uof $20^{\circ}$ 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-(s8;7* clueevhq a2:fm hns ;tjump goes into the jump with a speed of 14 m/s at an angle a: s*lhhnsm2;f8;veetq(cu 7of $26^{\circ}$ 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 velocity of 52.5 m/s at an ang*1lmr1nq c0kqte y73t1 mpc( ule of $38.4^{\circ}$ 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 an initiamj h336kmiajp0((rmkzzd t4:z ) g6erl velocity of 51.6 m/s at an angle of $24.0^{\circ}$ 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 aykvlvl *7g,0zh m av24t an angle 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 horizontally at 19.8f qbr.c7riy*)+k wq1:ix /n lr $m/s$ from the roof of a building 53.7 $m$ 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 level with an initial speed of e85yq)8 :ty7cuwyyr: bizbu +55.7 m/s at an ang:yu zt+5i8 7cy:8q eyywubr) ble of $37.8^{\circ}$ 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 m/s.oqsyp0wj/3n9g- imj3(we 8zg If you ran the same 39-gyj og3 wzmj08sw(qi/neprace on a day when you had a constant headwind which slows your speed by 2.0 m/s, the time it 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 due North, and.l9 c5is cx9m te9wupj*ne(b8 is in a wind of 50.0 m/s to the West. The plane's speed relative to the ground is( eci 99p8bwm jte5ulncs9.*x

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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 South (h l5b ep:34bno$270^{\circ}$) 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 sp ,vik6jlv s;* d-7kkaveed of 120 km/h is headed $30.0^{\circ}$ 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 m/s horizontally fires )qkiala.,l tlo6 2+ boa projectile with speed 50.0 m/s i ),.lt+o2a6l o alkqbin a forward 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 in still water is 8.0 m/s, is directed across a river withh:rel1(m : fm+ vt-xxl a current of 6.0 m/s. What is the speed of the boat (:lxmm-+:ehxf1 l vtras it crosses 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 15 m/s in still water wishes to t1,-5 f2chqz ddthlok /08y9ge5px uuu ravel directly across a river 1.7 km wide in whiczd gul y1/utd,- f525oh8uqkp9 chx0 eh the current flows at 6.8 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 motorboatax tk/z,xx48 g that can 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 should the driver h/k8xx 4a ,xzgtead 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 reaches the opposite ban*6q dlx3k,i,azdm nike(ka/)mql45w k in 6 min 40 s. She is swept do4*kwld mkiin q,xa/d(,l 6zm5aqke )3wnstream 480 m. How fast can she 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 river 200 m wide reaches the opposite bank ybri5h0sdqw 2 )jc)x2in 6 min 40 s. She is swept downstrxi)0r 22dj hqy 5c)sbweam 480 m. What is the speed of the current?

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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 1.80 m/s, must aim upstream at an angle o5; jq+to skay.f aj yt+ks q5;o.$23.2^{\circ}$ (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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