Suppose that an object travels from one point in space to another. Make a * r.xb: jlj6f xxe+r-zcomparison between the displ: -jrx*jxf.lb xr+6 zeacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneousigu ( po,uisn3yxzev b.-5;((del;mn velocity?

  A new car manufacturetn 0-ux6. yguzr advertises that their car can go "from zero to sixty in 8 s". This is a descrip60n tuxyu.zg- tion of

  An object moving in the +x axis experiences an accelerationr 3,- wqng/:rxyyrp.gi/p ma. of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow do z72n6d4azv;p :rn3rt 4t;j-ngp ypwewn as it approaches a traffic light. Make a staw z6rpy 4g-j:;zv2annd 37;per pnt t4tement concerning its acceleration.

  Suppose that a car traveling to the West (-x directio brab6be8t3wb8 o7y y.n) begins to slow down as it approaches a traffic light. Make a statement conce.ab376b8bbertyw o8y rning its acceleration.

  Suppose that an object is moving with a constantk/kh:vw x+z /v 6s)ddz velocity. Make a statement con6/zdv +s)/dwkzkx v: hcerning its acceleration.

  If the velocity of an object is zero, does it mean that the acbi9 ofzb7ql*n, /jc; 7cu z upl7s5-jjceleration is zero? Support yoop snqjj7 c,zbu*7-z/lcblif u;75 9j ur answer with an example.

  Can an object's velocity chaais2kwd 7g,z 5nge direction when its acceleration is constant? Suppordiwg5 s72a kz,t your answer with an example.

  Suppose that an object is moving with constant acceleration. 7rz. m 5 vlzqrl.do8,uMake a statement concerning its motion d rzo 8m.zu.qlv5,lr7with respect to time.

  Can an object have increasing fj0op rlt4yw;wv((s) speed while its acceleration is decreasing? Support your answer with an examppr fw)w(4l (;osj0ty vle.

  Suppose a can, after 27 7gb *oxjh4wksu 9vyr-e/cv an initial kick, moves up along a smooth hill of ice. Make a statement concerning its acck u7cwvv/9x7sh2jro 4yeb *g-eleration.

  Under what condition is average velocity equal to the aver(h1d03 vtn/ b5lguql nage of the object's initial1ut50(/n qb dlv n3lgh and final velocity?

  Objects A and B both start at rest. They both accelerate at the nz /nqa k-d8b.same rate. However, object A accelerates for twice the time as object B. What is the final speek.bnn-q ad8 /zd of object A compared to that of object B?

  Objects A and B both start from rest. The) lq1)wz .fea)hgg8kbu k9lg-y both accelerate at the same rate. However, object9 h -wlf)k1akeqg zb)g u)l8g. A accelerates for twice the time as object B. What is the distance traveled by object A compared to that of object B?

  When an object is released fromsdo5di; b0ho 23gyu9n rest and falls in the absence of friction, which of the following is true g0 o bs3dh;5n9iy2odu concerning its motion?

  When an object is released from rest and falls in the absence of frictb527l 6pgsh/jmv0m xeion, which of the following is true concerning hj e056bl vmx7 /pg2msits motion?

  Suppose a ball is thrown straight up. Make a statement about the t9 vwkf8b8;) uudn /elwob7g0 r)3xr cvelocity and the acceleration when the balfe rwgv8ku w9;0ot8c r n bl7u/)xd)b3l reaches the highest point.

  Suppose a ball is thrown straight up. b p+zlp 9bxn3k4s bc.6 What is its acceleration just before it reaches it + x64b9pzc3lk snb.bps highest point?

  Suppose a ball is thrown straight up, reaches a magc4nhujla qd0hv-q1.w:(r fg(gs +s ( ximum height, then falls to its initial height. Make a statement about the direcu4jd:wr g0nq ac-((gq.h gf ( svs+hl1tion of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a /kp l-nk8vji( maximum height, then falls to its initial height. Make a statement about the direction of the velocity ankk-piv (n j/8ld acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a statep+sbmebfk5z 2qil b 3er)5z/m5,gfr(ment concerning its accele)q r e5/f2(eb pflbbi5ks 53mzzg,+rm ration.

  Suppose a skydiver jumps from a high-flying plane. What i 4(p0f3bz bt5eeakz9 ks her acceleration when she shbp t309efeak5 b(z4zke reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identical second ball isex, o)n)vhs8te sy70n 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 )xev)te08 ,ohysnns7does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, ball B zx 7k1 kyc**is4s /itjbcj1(cis dropped from the same building. As time procy7*c 1sb*i(kkx i/ czjs 41tjgresses, the distance between them

  Ball A is dropped from th87+ vot;iqu2t ex(kov 0qc uj/e top of a building. One second later, ball B is dropped from t +0cuxq qt uvijk2t(;o/oe8v7 he same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is th4rr zssp43(t 10 i2 mapknm3hprown up, and the other is thrown down, both with the same initial speed. What are their speams4pzrmth4p i n1 srp23 k03(eds when they hit the street?

  A brick is dropped from the top of )ccetb1 otyz9aa/. v1 zvi/ h,a building. A second brick is thrown straight down from the same buildingt 1e)c/1t bcoy ,h9 avz/z.via. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The posi.ivz66cqd 8m1wqb:k q 9q l(yition veq z6 idw(:iqc1y. q9b 6m8lqkvrsus time graph of this object is

  An object is moving with constant non-zero acceleration in aj5xp0yta s5 7)tvu:zczz( mz1m1u a) the +x axis. The position versus time graph of this object ism:p5z)zutc zt xv( u)a1ma0ysj 5 z7a1

  An object is moving with constant non-zero velocity i6ao e*2wgc 2ph0sid 0 ypjldx0us /;u)n the +x axis. The velocity versus time graph of this objec2gs;jp 0s6i 2axlu0/)0chwdu y do*p et is

  An object is moving with constant non-zero accelergy,o;gz+4 y;f q xt/b nk9hfe.ation in the +x axis. The velocity versus time graph of t bz4 9,.y f/kgfyt ;no+;hgqexhis object is

  The slope of a positive/4 vy9oxz*mon versus time graph gives

  The slope of a veloccs:*(lgms(+ld+zlxv z8/*ccsl 9mt x ity versus time graph gives

  The area under a curve in an accelera87;mtp3wvu,q8 numv ntion versus time graph gives

  The area under a curve in a velocity versus time graph gives dgi: 256kqlhz

  If the position versus time graph of an object is a horizontal lgbp.fw*w nd3mm sk+f v 5j-x/n*8l :ifine, the object isl xbn*m/f f*jn .:m-w8vskf5dg+p3iw

  If the position versus time graph of an object is a vertical line, the object is)wen7vnp7v q9vny9 pfe : +hdhi,)+voj1zws5n zhd ov:n,ppw qfis j+v w 791)7)h5yven9+ev

  If the velocity versus time graph of an object is a horizod0rgir q(3b06 lf2f aental line, the object isbq rar6g0idl (fe2f03

  If the velocity versus time graph of an object is a str z pd.oscf,d,/aight line making an angle of 30 degrees with the time axis, the c/zodpd ,s,f. object is

  An object moves 15.0 m i2 eol0. la i i3d,yna*5iun(dnorth and then 11.0 m south. Find both the distance traveled and the magnl(0u*ale iii ,odyi52d 3.nnaitude of the displacement vector.

  A boat can move at 30 km/h in st mm3sk3-vblfzp/d amx ,aii;gz/l8 ;:ill water. How long will it take to move 12 km upstream in a river flowing 6.0 zlgkxa3v,d38//i:;fm a- isp;zmlmb km/h?

  55 mi/h is how many m/s? (1 mi = 1609 j xrrhxt7tfcn 9(my83-e43 cm m)

  What must be your average speed in ord nq6 i/x*vjk.per to travel 350 km in 5.15 h?

  A runner ran the marathon (appro(6z,kfd t9ry5 /dap elximately 42.0 km) in 2 hours and 57 min. What is the average spedrk/6,lztp (f yd95eaed of the runner in m/s?

  A car travels 90 km/h. Hol2/q os1d-nt mw long does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in .*ebyrje1 tz y0pi,v6b (,xhrke2ji/one year. The speed of light i e*x/ ,ze(jkt0iyp2br. hj,r y1eivb6 s $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 72 km/h along a straight road and you looklzu 1di 40vw4b to the side for 4.0 s, how fv 4 0w4udbil1zar do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (4i10qtgt;r 0o);1mt c5lfdr zp8,r jyt00 m), in 100 s, your average velocolc;t p ij1rqd58yrf 0tt0,t rg;)m z1ity is

  A polar bear starts at the North Pole. Ilmnpvu v m/51at1 2b+lt 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. This trip takes 45 min. What 1m l+nbpt1vv 5m/l2a uwas the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km lcq;fh*;3eai iyh /um90rmxsu.oy 3av// 1x keast, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes oa; crqfixx/* . my 39imka30hh /u;l/y1usv e45 min. What was the bear's average velocity?

  You are driving home on ao1/lh:vx n0yewh- v9oik0s m) weekend from school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometo1h/0 m:vnv0ih)k-o y9 sleo xwwn from school?

  A motorist travels 160 k.wrjhwb+ s-gs6qw:,xa l: g5j m at 80 km/h and 160 km at 100 km/h. What is the average speed owhq wax,:s j-br+w.5 6l: sggjf the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. , ,3f9zgw ,tk otimn0oWhat is her average speed for the trip?iftk, n ,z3ogow0 m9,t

  An airplane travels at 300 mi/h sou 1g/mhh /c,yr4 bi87eqnh8fm yth for 2.00 h and then at 250 mi/h north for 750 miles. What m4 riqh f7y n 1bhy8//me8cgh,is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who rpfgqc f .weva8r o5)3b*tl ;*muns 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 team B runner can have when the team A runner starts the final leg of the race, in order that the p )f 38.mgwerblf* tv5ao*c;qteam A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 9 s. +vk .5xd+l uy .1jtxlpThe car's average velocity during deceleration was 53 km/h. What was the car's deceleration while slowing down1xxd+jul5l.kp vty +.?

  An airplane increases its speed from 100 m/s o5, a c+co.*howo a,tuto 160 m/s, at the average rate of 5.h oo oaoa+* ,wtucc,$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acccx 7a- sgi18bn)dv1dnelerates at the rate of $2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

  A cart starts from rest v 3)phk5)rc zmfzg76i.jb lt: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?

  A car travels at 15 m/s for 10 s. It then speeds up with a constant qph9 s0v,gbv +acceleration ofb+ qsph,0gv v9 $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 5.5 m/s experiences a cwolxil7/:7zwstkw :9 onstant acceleration ofx w:i:wolzs/wk7 7 9tl $3.6 \; m/s^2$. What is the cart's displacement during the first 6.9 s of its motion?

  A bullet moving horizontally to the right (+x direction+sxs11mxz nd 9fl3t m yif 4r:z0i,xe6) with a speed of 439 m/s strikes a sa1f41 +f63tixm ld ,ixz ymr0x9nss:ze ndbag and penetrates a distance of 48.53 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is lau0ifi69d8haf9iaa )y o nched from a catapult on an aircraft carrier. It reaches 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 thhdfo i 9if9)6ia8yaa0e catapult?

  A car starting from rest moves with constantrraev,70: w m,lrvgw 0g+k.ex 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?

  A car goes from 40 m/s to 80 m/s in a distance of 2z*qi/kdaw+r7, muo 0n-;mu:0n )8wsvr bktrr00 m. What is its average acceleratirm0wt koz,kmuq0: 7/br i+sanud8wn -)vr* ;ron?

  An object starts from rest and undergoes uniform acceleration. During the ficzlu6,x 1 smn dme(5+orst second it travels 7.1 m+,s xum 65(zom1cd eln. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Ispi+vuz oq-,;nitially it is traveling at 16 m/zq+; po,s-vius. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and acav/uyhoawacdd+7:. 8 +h snm8q c/0tfcelerates 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?

  A car with good tires on a dry road can decelerate at aboun7uamyk d+u25dru8 )bjvd, c6 t $5.0 \; m/s^2$ 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)

  At the instant a trafrw-uw c,.ubq ,fic light turns green, a car that has been waiting at the intersection starts ahead with ar, u,cwq- ubw. 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)

  An object is thrown upward with a speed of 12 m/s on the surface of planet X 283gwrva(3 df1c9oq3efgkm2d dtv*f where the acceleration 9w8o2(gv d2gemtfa*33cfd dv3q rk 1fdue to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a spe2bxdqtf2/l +c ed of 12 m/s on the surface of planet X where the acceleration due to grav /+xc2qtf2bldity is $1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

  An object is thrown upward with a speed 9,brf2 pte -iyk;1zym of 15 m/s on the surface of planet X wher9rm, -bk1 it2;yyezf pe the acceleration due to gravity is $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

  An object is thrown upward with a speed of 14 m/s on the surfa u/cq)r -g9dtoce of planet X where the accelerat )g-/9rcotu qdion due to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually greater than 0.10 s. If your friend holds a rule i9n/qk i3; *wuo/q zr7-yaqibr between your fingers and relb aqio ;wn7q/ui/qr9-z *k3iyeases it without warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its v j)0bv9mar8v*ctno +l elocity after 3.00j8 r0c )v*o vabtn9+ml s?

  A bullet shot straight up returns to itsuus/,c im0xy3 starting point in 7 s. What is the initial speed of iu ymxc3s,0/u the bullet?

  A ball is thrown straight up with a speed ,g c*j oza86weof 36.0 m/s. How long does it take to return to its starti ea8o gj*,zw6cng point?

  A ball is thrown dowld kj73)gl5+5 lhl nzvnward from the top of a building with an initial speed of 27 m/s. It kd l+jh3nl7z vg5)l l5strikes the ground after 4.4 s. How high is the building?

  A ball is thrown straight up with a speed o6couj9;,v y 2. k -gq3exhrdpsf 30 m/s. (only fill in numerical value in the blankspjxr6 2sd .-ughk3vo9 ;cqy,e)
(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?    $m/s$

  A foul ball is hit straight up into the air with a speed of 390-ionuw6o08ph+yu bu .5 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 9 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 9.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1 .cd/q- 9hdtt0vo/:qhkb x px;y ou77u.0 s?

  In Fig. below, what is the velocity at t = 2.5 srbuj. u :vasf+1) sx3l+d aj1d?

  In Fig. below, what is the velocity a;hhau2h 5cdy5+wif n84 b;iu+1 rkwjy t t = 4.0 s?

  In Fig. below, what is the veloc9-evc9 clal7 k lht51j5a+ mctity at t = 5.5 s?

  In Fig. below, what is the average velocity 5 87aavand 3ivkr8e.n from 0 to 4.0 s?

  In Fig. below, what is the ta+ u3 m(ru/z qdp,w3zaverage velocity from 0 to 6.0 s?

  In Fig. below, what is the accelebraxia93b +se 953 zwiration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 s-jq k7p8pd qz8?

  In Fig. below, what is the average e adt7p;sq2xf5s df(0qf:7l/ rjf 9ioacceleration from 0 to 5.0 s?

  In Fig. below, what is the average accelerpnkzg74( ugwfz sj4q6,5y(c+sx, dniation from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to u8)x dvd cirs/16u sd.8.0 s?

Does a car speedometer measuruu4 h0oh:l*yq+ o9bc f8:mm qxe speed, velocity? {speed|velocity}

  An object can have a varyin 9j/we* kyf zc6in(b+ag speed if its velocity is constant.

  The velocity of an object sxwa5 . c zf9*h+3cljphk3s)acan be negative when its acceleration is positive.

  If one object has a greater speed than a second object, the first uz5womv9io a2z8,/ lyf .ty/amust have a greater accu8.mzl fi/ovz,t9y/yo 5aw2a eleration.

  Two cars emerge side by side from a tunnel. Car A if9- ho: :yyqejs 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.

  An object can be increasing in speed as its accelerati/x/t9kb nf i.gon decreases.

  A baseball player hiv3w,.c--ma :u01bnsilv tj ve xy b+2nts a foul ball straight up into the air. It leaves the bat with a speed of mxvt2anlwe c+ -snj 3,uvb 0- iv1y:b.$120 \; km/h$. 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)

  As a freely falling object speeds up, what is happening to its acceler9 xxm. 8l0udow9.mjcfation, how does it change ifmjfx98x.oml0 wd9 c.u air friction is ignored?

  As a freely falling object speeds qqk+0/qz +*mye ps u3eup, what is happening to its acceleration, how dom+q sqqe3 0uykze/p*+ es it change if air friction CAN NOT be ignored?

  An object that is thrml7 nthx3 3ejfi6g o/)own vertically upward will return to its original position with the same speed as it hlf 3xh 3)mt/ejgoni76ad initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero )0 93hykl2g brd sz2zsvelocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at the samz:-g.qres88x ezkrj*rr;j5c e time.

  An elevator moving from the second floo9 j miltk7+cs5r to the fifth floor making no stops along the way has zero acceleration alcsl+k5jm i 97tl the time.

  A rolling ball moves from n)j+j32f1xd:5uzlni+o re gu $x_1=2.0 \mathrm{~cm}$ to $x_2=-5.8 \mathrm{~cm}$ during the time from $t_1=1.1 \mathrm{~s}$ to $t_2=5.5 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.4 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=4.2 \mathrm{~s}$ is at $x_2=8.0 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight ch :.7xb p;gv9klkql* momplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 10.8 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its trainer in a stra s+ft5dn-gc61 ry cf0ze*1gy night line, moving 87 m away in 13.2 s. It then turns abruptly andc cg1rzfn+0e1d5yfs* -yntg6 gallops halfway back in 4.6 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.

  A car accelerates fro * x6)ngxiry)j/q7:e k6 dkdwz q:il.im $12 \; m/s$ to $22 \; m/s$ in 4.9 s. What was its acceleration?  (数值)  $m/s^2$ How far did it travel in this time?  (数值)  $m$ Assume constant acceleration.

  A car slows down from 03o znlx3 6pjkdw ph9*$16 \; m/s$ to rest in a distance of 69 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed rdlzi duv :-+5of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $3.0 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out o rbbg0ez:si04rt u 6-: -zz,ci8sqws ef the blocks to essentially top speed aboutegzu wiqc0:s e0isz84br-tr,-zs6 : b $11.2 \; m/s$ in the first 10.3 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)  $s$

  A car slows down uniylrgy l.uepq 7b-:q4.s: j7svk21nz w formly from a speed of $19 \; m/s$ to rest in 4.53 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m long on the g p 1yduu2-cc1(b5i;y ghsc,s highway. Assuming a de2(;g51hudcsybsi cu c p1 gy,-celeration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trucf6u )usnt:jb/k 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).    $m$

  A runner hopes to complete the 10,000-m run in less than 30.0gz1 ) iji*1m-t6 wbwex min. After exactly 27.0 min, there are still 1100 m to go. The runner must then acce jbie) g6w1wm*t 1-ixzlerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$