Suppose that an objecthdrcn8f:, 8c*bl ys;n travels from one point in space to another. Make a compar b8;fc hnc:8r*, dysnlison between the displacement and the distance traveled.

  When is the average vviy mug r o35 jxmbq:a23k(1a7elocity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises th y0incc ji 9e9,hpsuq:9o1s c0at their car can go "from zero to sixty in 8 s". This is a descripti1hceois:pu90jy9cc9,i s n0qon of

  An object moving in the +x axis experiences an accelerjcwhcocc. g 8dc :.5.,5uqgz vation of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traddbeu 8) ce2q/ muyboi998qa5bn7 o ;hveling to the East (+x direction) begins to slow down as it approaches a traffic light. b/8eadqu)mebu99;c 527ybo oqhi d n8Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slo3b9qv u tt+v)nw down as it approaches a traffic livn9vt 3 uqb+)tght. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make at*yy dn70-mn pl7.l3hj.hw wd statement concerning its acceleratiomt7-l.n 7 dwhhyd*y 0l3.nwjp n.

  If the velocity of an wzv1q l)pe,vgr 6j3q :object is zero, does it mean that the acceleration is zero? Sup qp)ez3,vrjlvw1g: q6port your answer with an example.

  Can an object's velocity change direction when its accz lisrsz)x 8/+eleration is constant? Support your answex sz/ rzi)8sl+r with an example.

  Suppose that an object is cfrbmkc+1dk c-:brdpu *:7jr.d3s )f moving with constant acceleration. Make a statement concerning its motion with respecs) b71r:cf3d ckmrpf.+c: k-rd *djubt to time.

  Can an object have increasing speed while it 1 hw06lts ew1p9e-j. vde*nbbs acceleration is decreasing? Support youe0w1.6- vbjd steb*h1l we9npr answer with an example.

  Suppose a can, after an initim8p fzckb;n r 8ln l8rw+m98i,al kick, moves up along a smooth hill of ice. Make a statement concerning it nl8z ik+ 9mrw;8nrl c8mp8b,fs acceleration.

  Under what condition is average velocity equxwp jx(9 dpkds 90w dj;17if+cal to the average of the object's initial and 0c 9p 7iw1(+d9xp;dkxjfjswd final velocity?

  Objects A and B both start ay3j/wo8 nh a0xt rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final w/o hj8x3 y0naspeed of object A compared to that of object B?

  Objects A and B both start from rest. They both accelerate at the same rate im p4b;.)du*: uzgyov. Howevpbu:)g4modu*iy vz;.er, object 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 from rest and falls in the 2dg6id7x aue pb+*9vr absence of friction, which of the following is true concerninr6p+ u2 davd*gi7xbe9 g its motion?

  When an object is released from rest and falls ms3.mbf2.zl ithxij*fo(2 z.el 1(f y in the absence of friction, which of the followi.jzoi *22sb.l zit1fy. hl 3m(xeff(mng is true concerning its motion?

  Suppose a ball is thrown stra1a1 0o ikzujljs.7u)-sjtav /ight up. Make a statement about the velocity and the acceleration when the ball reaches the tz0)ulv1j7ia/- ok.1 js ujsahighest point.

  Suppose a ball is thrown straight up. What is its acceleration just kvlv d+p: myp;9 m550mc jon(wbefore it reaches itswmj;mk+v po0yd5 pn vm( c95:l highest point?

  Suppose a ball is thrown straight up, reahgvk+cx9j fx7n8b9*lh83 iq pqfec./ ches a maximum height, then falls to its initial height. Make a statementv8pjec9hbxi.7c9k h* /n 8qfgxq+3lf about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, theb .,kdiu5d:84qi kngnn falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ballu:k qd.i inkg,8n5b4d is coming down.

  Suppose a ball is thrown downward in the absence of air 11x aa8ldwa er3l9rt :resistance. Make a statemen3l91ax8t re1a:w ldar t concerning its acceleration.

  Suppose a skydiver jumps from;r,dmldg1wq m8zomu0(n nj1ak5x o 8 7 a high-flying plane. What is her acceleration when she she reaches terminal nxr1z1 ,w mkuj7an 5(8o;0ddmq8m oglvelocity?

  A ball is thrown vertically upward with a speed v. An identical se5z r6 nmdzo y1tvb52f2/jfl4 .zqqbe4cond ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to t1lfjq4/r52zzby2 6edzo m .f4bnv5 tq hat of the first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, ball B qw68e: g 6rwa;qv ;qxl*9ojrcis dropped from the same building. As time progresses, the dis*6r;ew6cla9;q r xvw o:8qjqgtance between them

  Ball A is dropped from1rjaz kw4m:;q 1g sk*u the top of a building. One second later, ball B is droppe1aj q;m1g rk k4suw:*zd from the same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tiyb */t kjwmh 1cydhw+8r))t.all building. One is thrown up, and the other is thrown down, both with the same initialrt *tb.)wm+ ih) y8/ hcwykdj1 speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown straightsj1 mt:r-um 5dt0 ybv+e43l jt down from the same building. They are released at the same time. Nee-ttd10bjr5t mmuys3 4j+: lvglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axk7l wdr)rh;n66.hb4 qt1mnz tis. The position verw 1h7tlzqr bm)krth6nd ;64. nsus time graph of this object is

  An object is moving with constant non-zero accw crsanp3x7 8 cmho-.u.*c1bheleration in the +x axis. The position versus time graph ochc18u3.*-ao 7mpws ncx.r bhf this object is

  An object is moving with3q38r exw+fkpcky 7 cf)ys t/- constant non-zero velocity in the +x axis. The velocity versus time graph of 3 /cs 3-+wy7pek8)qrftcfyx kthis object is

  An object is moving with constant non-zero acceleration i+p3 yxbuwz1 4krz j89kn the +x axis. The velocity versus time graph of t3kx1z+ ywr 8zup9kj b4his object is

  The slope of a position versus time graph nxwq +f.9zdm3 gives

  The slope of a velocity versus time grapsxvm, k6;hi ;c9+ kdf i;0thhbh gives

  The area under a curve in an acceleration versus time grap4rq972/hxrbhje( jeeh gives

  The area under a curve in a velocity versus thv . 0(pqdpa/time graph gives

  If the position versu/p -l( ddw+yq isjx rq1e3jh9(s time graph of an object is a horizontal line, the object isp(j1e j +sd-/9ir h3lqdy(qwx

  If the position versus time graph of an object is a verticabzqp5 j+1 jayzd7s+0 wl line, the object isj0s7ad pz y+ 51zq+jbw

  If the velocity versus tih 3hpd mtegl2 -m5*2olme graph of an object is a horizontal line, the object io5lmeht *pdg32 l2-mhs

  If the velocity versus time graph of an objecto.*p28um4g+ awen phl is a straight line making an angle of 30 degrees with the time axis, the obhmn+epapg.olw*u 42 8 ject is

  An object moves 15.0 m northkgeb 8:2 )b 5phk :c,qqw3lfgc and then 11.0 m south. Find both the distance traveled and the magnitude of the displac)f8:kcceghwkpl q52,gbq:3 bement vector.

  A boat can move at 30 km/h in still water. How long will it take to0gw y3 +z--wdsbu 3byl move 12 km upstream in a river flowing 6.bs3dwyug+0y-lb 3w z-0 km/h?

  55 mi/h is how many m/s? (1 mi mi7w7y7+zyom = 1609 m)

  What must be your average speed in order to travel 3505*3cn panhue5 km in 5.15 h?

  A runner ran the marathonztmzemo;kgo6t6 *5 4 l (approximately 42.0 km) in 2 hours and 57 min. What is the average speed of the ruot6 k lmgtz5*z;m 46eonner in m/s?

  A car travels 90 km/h:cvz0.s sxxqm/aql aur l 3.y)8xt/m0 . How long does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one yeaa.vmo/w dcmn xz -1b:ygk)w cq8 x0i.9r. The speed of b d..1w:w oyqnmc)aix8 0c k-mv 9z/gxlight 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.)

  If you are driving 72 km/h along a sttkqe :q/-9-dsj tuur3raight road and you look to the side for 4.0 s, how far do you travel during this inattentive 3j-uktdrut- 9/q:sqeperiod?

  If you run a complete loop around an outdoor )ayef:l- n; 6mt wbqbc, czx7dkce1*4track (400 m), in 100 s, your averagcd c;e m1w) nblz*:a k,6t- f4qy7bcexe velocity is

  A polar bear starts at the North Pole. It travels 1.0jwz; ve-v98 h9r6fedv km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return8;hv6 wjfv vd99r-e ze to its starting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km 9a*h1ft 2uizc south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to fh ia *utz9c12its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 mile2o xl; ;:eh xss4x op0(7xjzujs. 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 hometown from sc (sexj ;:ou0 hzlxo27p4xjsx;hool?

  A motorist travels 160 km at 80 km/h and 160 km at 10r* zxh,(u,cpmzc1k b1pk(rjt+b) wt u55)vs j0 km/h. What is the average speed of ,rrzm)j u,wt(v*h+ x 5zpk t(ckb1j5cb1p) us the motorist for this trip?

  A motorist travels for 3.0 h athdmqrdc6 smo- f/.6v / 80 km/h and 2.0 h at 100 km/h. What is her average speed for the trip6 rsdhv-o.6cq / fm/md?

  An airplane travels at 300 mi/h souju9; monjq,sq 26ugr ;th for 2.00 h and then at 250 mi/h north for 750 mil;mugosq 6;nrqj, 2ju9 es. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) 1 3q z3;g6 cwx xj8muvqhu: ts s19-kh*)jhrpufor 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 ru9: uvsr g8*1;j)uq ztmh63c sh - u1w3kpqjxxhnner can have when the team A runner starts the final leg of the race, in order that the team A runner not lose the race?

  A car decelerates unifsdnc6:ix.o(e ormly and comes to a stop after 14 s. The car's average velocity during deceleration wace6.ix so(:dns 64 km/h. What was the car's deceleration while slowing down?

  An airplane increases its idl2e0de+o1b +y*z2rbzwu4q speed from 100 m/s to 160 m/s, at the average rate of we+r2zb0 d*1i4zdo2+ ybleuq$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at thn2rq5kjeom9-*3qkw awx 6g- ne 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 and accelerfv*hcfpeu8l p;3yf74(iq dhd44 7elmates 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. Ivhurp q.o8v g/4fat8cc::np4t then speeds up with a constant acceleration cgvp8 :8r/ cotvq4pfh an:u4.of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velo 5n:*drvh6 pnxbkelim7)3t -h mu+hv9 city of 5.8 m/s experiences a constant acceleration ot+ 5 -h m9n d7ph6ikvh*xr ):ulv3ebnmf $4.7 \; m/s^2$. What is the cart's displacement during the first 5.2 s of its motion?

  A bullet moving horizontally to the right (+x m/su* 6injm fnu3 1+y3zmw6rb direction) with a speed of 538 m/s strikes a sandbag and penetrates a distance of 91.91 cm. What is the average acceyn m+3ru*wbn36 sui6j/z1fmmleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an9 fnv ttt58wjsp8 ob7/j es9t8 aircraft carrier. It reaches a speed of 42 m/s at the end of the cs8 otw889 7pj5ftten9/ bvstjatapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves wie)n:y,cx qbm6iw, ,zme5 rc s6th constant acceleration of $2.0 \; m/s^2$ for 10 s, then travels with constant speed for another 10 s, and then finally slows to a stop with constant acceleration of
-$2.0 \; m/s^2$. How far does it travel?

  A car goes from 40 m/s to 80 m/s in a distance j8sya1 jl9jz-of 200 m. What is its average acce-sjy jjzla 189leration?

  An object starts from rest and undergoes uniform a.)wxak8 g,ucz vpq-:pc(ayjn y; 5 i(ccceleration. During the first second it travels 6.2 m. y c-)8cqvuac k. nzip;gpyaj 5:,(w(xHow far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initially i8k: t0xjxtw emj20ql:t is traveling at 16 m/s. Three j0mlt2w : ektx:xq80j seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from re78s z1:r wlpmt/n0g zdst and accelerates uniformly at $3.0 \; m/s^2$. A second car starts from rest 6.0 s later at the same point and accelerates uniformly at $5.0 \; m/s^2$. How long does it take the second car to overtake the first car?

  A car with good tires on a dry bsa hlsn1t6 bd6 e1hooi.l8( 3road can decelerate at about $5.0 \; m/s^2$ when braking. Suppose a car is initially traveling at 55 mi/h.
(a.) How much time does it take the car to stop?    $s$ (only input numerical values)
(b.) What is the stopping distance?    $m$ ((only input numerical values)

  At the instant a traffic light turns green, a car that has been a+t b2 w-qf)tp-:ji/4 ,d wn suwzebr,waiting at the intersection starts ahead with a const,-b-wt)+j iw,p u b f:ewat qr4s2zdn/ant 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 wvq px /hg5acz es 1/uv0t:ot,4here the acceleration due/05/t4v s, vt:pac1oqze h xug to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12b( nm9 j+5+kmbwzp md 9w6o3qo m/s on the surface of planet X where the acceleration dmo99bon b5+w+ zkj3(mqmpwd 6ue to gravity 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 of 15 m/s on the surface of vf*y 2q.48iiy 8myllhplanet X where the.yh82vyyqlm8 4ii* fl 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 su8rtlv.d x z55r)rwa /krface of planet X where the acceleration rk. /zv5wdtlxa) r85 rdue 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 ruleg,)rgh1 eemc1o 1j- fkr between your fingers and releases it without e1h gg-m,fkj coe1)1rwarning, 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 velocity afteh4o64y6e3s8yyl -ukf1kg w lqr 3.00 s6ye 1 h4k4fkylwl-6sgq you38?

  A bullet shot straight up returns to its startic( tz57m 0eohkng point in 10 s. What is the initial speed of t k5ht0oce7(z mhe bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does it tak0 tbk ;.me 1xy43lzxkre to return to its starting point krx;1e3l k xyb0m.t4z?

  A ball is thrown downward from the top of a g(zfbbgg jc :j p9+4s7building with an initial speed of 11 m/s. It strcj7gp zf+s(b4j g9gb: ikes the ground after 7.7 s. How high is the building?

  A ball is thrown straight up with a speed of :iqp b5 boo7* 7f4fefo30 m/s. (only fill in numerical value in 5bq bofo7fe*o7:p4fi 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?    $m/s$

  A foul ball is hit straight u;cv,1b+e or-m)tvj 2zw1uk0jkj:; ea aqzc,jp into the air with a speed of 28.8 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 3 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)  $s$

  In Fig. below, what is the vel8,frkgz)o vl+*;wud; 4 j jkcgocity at t = 1.0 s?

  In Fig. below, what is the velocity at t iqwoyx 0uh/e4ssty7we14n.mlxw a3 9 h(43xe= 2.5 s?

  In Fig. below, what is the vel ob -:qlm9z7pbocity at t = 4.0 s?

  In Fig. below, what is the velocity at t = 5.5 s?dyhy9 8 3fj ezxc: s-sv/w6*hp

  In Fig. below, what is the average velo a di)yq1u,-s-ztoz*tcity from 0 to 4.0 s?

  In Fig. below, what is the average velocity from j-vku x7p 6j,dbro1o+0 to 6.0 s?

  In Fig. below, what is the acc(u :7gvy(ci* hez,ou+bg kz 8ueleration at 1.0 s?

  In Fig. below, what is the acceleration aeyw2 fs.uzv /4t 3.0 s?

  In Fig. below, what is the aw6w aj1v o+ xrx5gw8n 2o8h (xu1jff6everage acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleratio*r 21pfxypbf5+o (jjwn from 0 to 8.0 s?

  In Fig. below, what is the displacemerg 7 + 19f.bp eeznaeb51r0kwsnt from 0 to 8.0 s?

Does a car speedometer measure speed, vnddui 9w1i29telocity? {speed|velocity}

  An object can have a varying sp 3acq2ij )hi4need if its velocity is constant.

  The velocity of an object can be negative when its0asxf3k9 e er/zrkt4otp8*r - acceleration is positive.

  If one object has a greater speed than a second object, the 8oel( l j7zuil5 6r5vr ),jbwifirst must have a greater acceleraleu (55ri wzjbi,j8) vrol67ltion.

  Two cars emerge side by side from a tunnel. Car A is travelp i4 .en2yonlw:f tmazpp 9j il2z/*8s(gvo17ing 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 f 20rw; -xxgmuits acceleration decreases.

  A baseball player hits a foul ball straight up into t thrsb8z b l(/4sjg- tu13rpv0he air. It leaves the bat with a speed su4lb- 0t 8z r3r1 hsgj/bpvt(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)

  As a freely falling object speect)h0y f sm,lg*8du6y ds up, what is happening to its acceleration, how does it change if air friction is ignoumt6s0,)dgycflh*8 y red?

  As a freely falling object speeds up, what is happeldogli8c-o:v z7r6xzfn d,+5ning to its acceleration, how does it change if air friction CAN NOT be ignoredx:- cd6i 5olzoz+gl v7rn ,8fd?

  An object that is thrown vertically upward will return to its original posv mjs1.e sn,oszj0 gwv* qb+ -tr4q0,vition with the same speed as it had initimo0+j40 ts,szsb q v1v *ew,j- v.rgnqally if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleratxo *a*lc 0;rot bas.c;ion at the same time.

  An object can have nonzero velocity and zero acceleration at the same *8 t49)f*tqozebhp ,ngce:bi time.

  An elevator moving from the sec r96rp y94osedo9x q //zl2qyes1,rl vond floor to the fifth floor making no stops along the way hr vl, r4d 29619/yqzy/ ee qxoposlr9sas zero acceleration all the time.

  A rolling ball moves fro 4kml*wsl5:/sev p (zum $x_1=2.6 \mathrm{~cm}$ to $x_2=-4.4 \mathrm{~cm}$ during the time from $t_1=1.4 \mathrm{~s}$ to $t_2=5.8 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.2 \mathrm{~s}$ is at $x_1=3.4 \mathrm{~cm}$ and at $t_2=4.4 \mathrm{~s}$ is at $x_2=7.8 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps .flk (b;-sk1bvvwn(qaround a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 12.2 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 straight line, moving 99 m awm kd-5xue5 gruz 3d8l/ay in 13.8 s. It then turns abrup3mu- 5kru /5dgzdl e8xtly and 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 from h2t)l-j;d6lzmam 1x z$12 \; m/s$ to $25 \; m/s$ in 5.1 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 tmfvz v./lnfb()bib02uk67jez6h ;b$18 \; m/s$ to rest in a distance of 55 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a .p ix sq+o/le5;t ak1b)n9dn uspeed of $28 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.5 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speed a0k7 h(zmua7;(s obxpj:m ;a )fsx jgu2bou; ;(s7fu xm:pabmx oz ga0h(j 27sk)jut $11.5 \; m/s$ in the first 14.2 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 uniformly from1 4htb-txbaleto086m;cqd i ; a speed of $16 \; m/s$ to rest in 5.38 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 96ine(etf pqr 6) :rzho)1q4rm2 m long on the highway. Assuming a decele4 hezrni q r)e)16p(:tfrq6omration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck go 7(( ffedoyfz/a9 :iuking $25 \; m/s$ 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).    $m$