Suppose that an object ffiur;jtrt+:4rb0 s-d0q nhpu2g*x 0travels from one point in space to another. Make a comparison between the displacement and t0f * tts:r xgjrd+pu2rq40b0i h;f -unhe distance traveled.

  When is the average velocity of an object ez odkow c un4gc08 m.rg egzx-gu6r/8 52+ni7aqual to the instantaneous velocity?

  A new car manufacturer advertises tfsllm, .qq uq zo)+rr800uhf 1hat their car can go "from zero to sixty in 8 s". This i.lqqfrzq+smlf1)uu80, ho0 r s a description of

  An object moving in the +x axis+ p/ 7 flxdvuu8k/ju*w experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling fk)h l uwo::* 59l1*tux,/b avuypqltto the East (+x direction) begins to slow down as it approaches a traffic light. Make a **tl 1 k)/ob:l5x f uv9,twq a:yupuhlstatement concerning its acceleration.

  Suppose that a car traveling to the West (-x ddine6iho8w7b2/ cb ec8 ;j1du irection) begins to slow down as it approa 7ie/ew28;c6 bnb dho 1jidcu8ches a traffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a conj wn8symn64q6 stant velocity. Make a statement concerning its accele ws4j6y8qmn6 nration.

  If the velocity of an object is zero, does it mean that the acceleration is ze( pca7bwzsi(7 ro? Suppo (sp77(iwazbc rt your answer with an example.

  Can an object's veloczyrkt;7(zr1 iity change direction when its acceleration is constant? Support your answerr yztrk1;i7 (z with an example.

  Suppose that an object is moving with constant acceleration. Make a statement0t-h6( ul( xy.)vy 0ww vmbegz concerning its motion withe-ymw)6 (hbxtu0 (w.vzg0yvl respect to time.

  Can an object have increasing speed while its accelerationr r3(pfaff f9)y9*qu 9h bow;gt 6u cvj,l24pi is decreasing? Support your arh2p4qy69rij*cbv(;3 ,9put)f uf9a goflwfnswer with an example.

  Suppose a can, after an initial kick, moves up along a ;o 0jdqs,noldxk x/yno op;28 r0tp66 smooth hill of ice. Make a statement concerning its acceleratid ;s; xr2opn6/, kd0jqyon80o olx6tpon.

  Under what condition is average velocity equal to the average o6u0wow(2 fhvsi,2 yz uf the object's initial and6uy2s(iw 0,f ovz2w uh final velocity?

  Objects A and B both s nh.;bn(pv:gjtart at rest. They both accelerate at the same rate. However, object A accelerates fop; .nv g(h:jbnr twice the time as object B. What is the final speed of object A compared to that of object B?

  Objects A and B both start from rest. They both accelerate 8v 1djhaa 4(vroeu(we i:na7+ at the same rate. However, object A accelerates for twice the time as obj voe(n1r va a(d8w7u :+i4eahject B. What is the distance traveled by object A compared to that of object B?

  When an object is releasxs1h zyz7kj)2t cf;jwi9*d u9ed from rest and falls in the absence of friction, which of the following is tc2wdz*huzj7jk) y91;i 9tf sxrue concerning its motion?

  When an object is released from re* 7a5vjt 1cidmflx 1*d7mj.vlst and falls in the absence of friction, which of the fol* mmvjfdj v a11.di7 xlct5*7llowing is true concerning its motion?

  Suppose a ball is thrown straight up. Make a statement about th7j gmush: 8v9y2io)ju e velocity and the acce)i7 :vju92y mgu8ojshleration when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before ihn/-gpp,v bh- t reaches its highest -h-/p, pvhbng point?

  Suppose a ball is thrown straight up, reaches a maximumifa*p9 /dpzv,t .a+j u height, then falls to its initial height. Make a statement about the dirj ,ip/a+9a zftpdv.u*ection of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to i s,xgm r0,1titc( ; vwhs2rr0ots initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming dowtmw1s , tohs,v(g20rx ;rr i0cn.

  Suppose a ball is thrown downward in the absence of air resistance. Make a state55ip4a9oxm i,j 4n l: (auoanymep i: a4l9n5jmax,i uno5y4(o ant concerning its acceleration.

  Suppose a skydiver jumps f;pdj v 7qr2)pxrom a high-flying plane. What is her acceleration when she she reacpx q) j7;prvd2hes terminal velocity?

  A ball is thrown vertically upward with a spej klr/;by qk8-/ cj)ihoge54eed v. An identical 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 the4kc/) h jgj/8i k-lreb5oqy; e 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. O1 bdul5ox1;h6wkd8z d ne second later, ball B is dropped from the same building. As time p8dkx61dlho u1; w db5zrogresses, the distance between them

  Ball A is dropped from the top of a building. One second later, ball B is d:r cs 4olz qieuq)1yot 20m+1jropped from the same building. As time pro: u tq+2c rlomjez0i1 y1q4)sogresses, the difference in their speeds

  Two objects are thrown from the top of a tall buildisalkdm o)t 2 )8sxt9t+ng. One is thrown up, and the other is thrown down, both with the same initial speed. Wha )adolx)+t tkmt8s9s2t are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick spi )/e7 p alod3uj+(+) hvctnis thrown straight down from the same building. They are released at the same time. Neglect air resistance.)ad/7pp ) s+tc3uihl(ejo + vn Compare the accelerations of the two bricks.

  An object is moving with constant non-zero ve8ti fnlgj 5t0-locity in the +x axis. The position versus time graph 0ij5ntltfg8 -of this object is

  An object is moving with constanb e+qkjg; zxa j/cl c. 593oxs5 /mwds.4,tszlt non-zero acceleration in the +x axis. The position versus time graph of thisa4kqme z.s lj +,3x sx5/ c 9./dj;5gbswltzoc object is

  An object is moving with constant non-zero velocity in the + 0nrpv0k z7i:7 nucwd8x axis. The velocity versus time graph of :nzvuikwc 8 077rpnd0this object is

  An object is moving with ctz2hqg znpqj-2m,0fq k gz0, k),,jtdonstant non-zero acceleration in the +x axis. The velocity versus time graph of this objecn ttjzmpzhk,,j 0- ,q,z02 gqqgk)2 fdt is

  The slope of a posit8gt wr6:5at 7ea*8xo4j p zz)i4rgvk ssrv u79ion versus time graph gives

  The slope of a velocity versus time graph givpii jj9pn;b(tx4::9wch9n p nes

  The area under a curve in an acceleration versus time graph gir(x+i)(:ayqko+o((nng1vwt x g tz :jves

  The area under a curve in a velocity versus time graph giun-f)eh xyak. i;x,: wves

  If the position versus time grapb3 pusw:3o8g4xihps2qd 7 f /bh of an object is a horizontal line, the object is7o3uhxbp f 48pq/sgd3bisw:2

  If the position versus tigg 2z(c5 stb1ime graph of an object is a vertical line, the object is(2zct 1si bgg5

  If the velocity versus time graph of an object is a horizontal line, tso0+w 7(:d; xuk+ kttkb ufyb5he object isu t+sydt5xbk7f( +o0;b:wkku

  If the velocity versus time grauw7 r0bh(4hilp -i)uyph of an object is a straight line making an angl7uip)wlbhyui ( 0r 4-he of 30 degrees with the time axis, the object is

  An object moves 15.0 vs- )ybfxr;7yk+9,x . coja xkm north and then 11.0 m south. Find both the distance traveled and the 7;yxb joy+avr. kk-xcs fx9,)magnitude of the displacement vector.

  A boat can move at 30 kmwf+ 5;qwyu 4lj4z/ ilb.1ywvsi z8ug+/h in still water. How long will it take to move 12 km upstream in a wj;f1l4+yuu.5 z4b8/wgwvyl +izsiqriver flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 16bt1.wi w,uwm/kw3 d:b09 m)

  What must be your averageu :dgcz/;d ,e/us+e+z/n k kbh speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 ma o d.l80oym)hin. What is th0ayhmlo. 8)do e average speed of the runner in m/s?

  A car travels 90 km/h. How long does it ta, plyb:ib8;l1wd 2msoc0f il 4ke for it to travel 400 km?

  A ly (light year) is tsq(e .huh ;o wgz0i;*:z. xgcche distance that light travels in one year. The speed of l.z .zoh*: uci(xc;h sqe;gw g0ight 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 straight road and yourq3y q n;rmtonk.4(oohs9r3v 4q1 1c l look to the side for 4.0k loqcr n9(4qqh1 33 4rnsmyvotor1;. s, how far do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (400/m0mngxd j)gquo 98,z m), in 100 s, your average vo8gg, qj) zm/numd0x 9elocity is

  A polar bear starts at the North Pole. It trspb -1)flos0 xavels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its startingb)ops f1lx s-0 point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the )xd*aj03 vunjNorth Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km wes0ad j* )vnuj3xt to return to its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend from school at 17* /y o/wnmsufswi 1v55 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 yourv1* umosy 1/if/7snww hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. What is v ji9 wtqzm 8.e,tkz8r4*e7nothe average speed of the motorist for nztiewoqzv jkr. * 7,88em49t this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her ave9 ccdig; py10wrage speed for the tri9 d0 iygw;pc1cp?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north for 4txfp ) m1jru.750 miles. What is the average speed for xtp4m1.ru jf) the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for te*br zm) k 7j+izb1jmiih2q+6z am 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 th)ji hm*+7bk1iq z zi2+ mbzrj6e team B runner 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 uniformly and comes to a stop after 12 s. The car's average gwa ,tjwss tj.7cu8:1tqm, 8evelocity during decelera jw7ut:8w.t8,j1 qg,eas tsmc tion was 54 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed eb mv6sk;;cx9to f (gcp.j)a)from 100 m/s to 160 m/s, at the average rate of c;) xktb m;cvpse96j g (af.o)$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelu;mw t6nyz 0wv 38aqj,erates 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 d p;5,5yekauhand 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 consta: tr4t hhb *j.tn46tfsb-o ybxi4eo*n 4jko.+nt acceleration xtr.- o4 on+ytb k f*h4ibejht :n4j.4tb*s6oof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velod)- rc6lp)xyl city of 2.0 m/s experiences a constant acceleration oxp)rc-)6 yl dlf $1.5 \; m/s^2$. What is the cart's displacement during the first 4.1 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speedjt2 wv*hxj/8 :3ctc zw of 239 m/s strikes a satwcc38z/ t 2: jjh*xwvndbag and penetrates a distance of 97.08 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catbgrkp,l;ni9e(fonw;; 1p0e y 9pin /qapult 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 the ca; (y9ke 09w,pgqni;1pnonri/ febp;ltapult?

  A car starting from re5-4v umvjep2f st moves with 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 of 200 m. What is its averagejnvp 5 z gmbqh9:9;;/uqdm:ms acc;9nm d mj:hpq gub;zv9/sm5q:eleration?

  An object starts from rest and undergoes uniform acceleratiot r+ug7:2g 3-vu4omn ktc;n0ntqf0f mn. During the first second it trnt7m +ttv n0r23ocukgg ;4m0- uqffn:avels 5.1 m. How far will it travel during the third second?

  An object is moving in a/3rpk5c *f r9glk+)kso+fx c k straight line with constant acceleration. Initially it is traveling at 16 m/s. Three seconds latef+ok+s r kx*pklc3 5rk 9)gfc/r it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates unifor. 3gu/r 7rvhlfmly 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 ,rs x,e:l70yyec o2wr 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 waiting at op n 5v,q mdi7)kc)v)2s)qqmh the intersection starts ahead with a constacd oh )spnm)qq 5vkq,7mv) )2int 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 surfac:zlwcy *k* yp/-0nrb te of planet X where the accelerati-c*ply/t0 z:* kybrwn on due 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 12 mey2:va9jcqkfzh ,9: 4hw0 fgx/s on the surface of planet X where the ahfwfykezvxj 420, 9hgq: c:9acceleration due 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 wirpple7 ,ry .,gth a speed of 15 m/s on the surface of planet X where the accelerate ,yp.grprl7 ,ion 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 surface of pl89 nvn j)rbz/d wkpds(j3 yk2t 6a2ut3anet X where the(rvtdp )a9 s/njdn638jt zwkk32 yub 2 acceleration due to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usu)5/ qy xlwxx0.8y owaeally greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can you exq .5w/ aw80yeyoxlx) xpect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/f ;;;ptp )d3ab t;ffnds. What is its velocity after 3.ff; fp ; p;t)nb3d;tda00 s?

  A bullet shot straight up returns to its starting pohgf uhk4,tmvro0*p-7int in 5 s. What is the initial s pof04h -, *hgu7vkmtrpeed of the bullet?

  A ball is thrown straight up with a speed of :0m zz4 uck(ofrfbx** 36.0 m/s. How long does it take to return to its starting point4:k*uzmfz rx (b0cfo* ?

  A ball is thrown downward from the top of a building with an initial s/d; ojobxm2r ; a4sd+npeed of 25 m/s. It strikes the ground axondj42sam ;rd ;b+ o/fter 4.6 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fil8psd7 q4iy+ ydl in numerical value in the bdps+y 4qdy8 7ilanks)
(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 intouxaq ghf)/cvzpa n5 7rp24u)3 the air with a speed of 36.2 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 2 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 10 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 10.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1.0 sizv5op*pxssy/t8h ,/ ?

  In Fig. below, what iz,7tk0niq;fz0e(4f u es;pry 3o f g4vs the velocity at t = 2.5 s?

  In Fig. below, what is the velocixf hw6f5ff*9(ndvxf uxhz0 lnu5/-x0ty at t = 4.0 s?

  In Fig. below, what is tkt3pxurmk 30q(tffw6 ;0j/ yshe velocity at t = 5.5 s?

  In Fig. below, what is the average velocity f+ppqni4p l8d 1rom 0 to 4.0 s?

  In Fig. below, what is the average vek,3 +ylqdmfdc0 o ;q6tlocity from 0 to 6.0 s?

  In Fig. below, what is ti3sfdfe;) 0mdr,2.g2qx kljz02 uij i he acceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0gch (,m7xp j,f s?

  In Fig. below, what is the average acceleration fr :io2k ,qnyzo68o .gycom 0 to 5.0 s?

  In Fig. below, what is the average acceleration frb*.2h f mf0oe8jdcbi0 om 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to 8.jf. h7q(wpyq9q bsu-0 0 s?

Does a car speedometer measure splx,:wu t 6unb.yyn:-i eed, velocity? {speed|velocity}

  An object can have a varying speed if its v 1h f7sqm09palelocity is constant.

  The velocity of an o0 ;yndv y r/-g:azb-fibject can be negative when its acceleration is positive.

  If one object has a greater speed than a second object, the first must havfsl,* tpycc)4cpb9 x 7e a greacfc b*tx4cl sp7p )9,yter acceleration.

  Two cars emerge side by sip t;r*.xmy r/rde from a tunnel. 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.

  An object can be increasing in speed as its accelerag a1l2ittg-a2 ld-gu-tion decreases.

  A baseball player hits a foul ball straight up into the air. It leaves 2x34t( 3tplmxeu 6zb.cve-l(wl v l8 hthe bat with a speed of 42wuxb8 lm6 . lez-3 xlvtc(vp(le3ht $120 \; km/h$. 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 spe9;.6hnkxcz1hj * cmloeds up, what is happening to its acceleration, how does it change if air fric 1 h6jkoc; xm.lhnz9c*tion is ignored?

  As a freely falling object speeds up, what is happening to its accecapzu4kc .f1,*c, x3mwbg6fp)n,ca a leration, howcp,cnkm ),c up .fc*,zg4axa1w6 f3b a does it change if air friction CAN NOT be ignored?

  An object that is thrown verticallu-s:.aw7c 9r 6f eemeay upward will return to its original position with the same speed as it h-9 weacsu6e e: .7arfmad initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration at the same gw orx;0/ n:kbtime.

  An object can have nonzero velocity and zero acceleration at t*jowy7fa v i 1*x-,sgnhe same time.

  An elevator moving from the second floor to the fifth floor makingjac:ti)g)snsjx +ulp)-3 y6 g no stops along the way has zero accelen3)+g atps)y)-6i lxugc j:sjration all the time.

  A rolling ball moves from 8ze1etpz /9y gtl 3(dal. hq)e$x_1=3.1 \mathrm{~cm}$ to $x_2=-7.5 \mathrm{~cm}$ during the time from $t_1=1.1 \mathrm{~s}$ to $t_2=5.4 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.7 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.8 \mathrm{~s}$ is at $x_2=8.4 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complevl 1t- 4ky+tfqu2fox:te laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 9.0 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, movimg mmhfo.ec9 s;m6yqf.1bx 7-ng 112 m away in 11.2 s. It then turns abruptly and 1g7 c.xo; ysmebf6mf-m mh9.qgallops 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.

  A car accelerates from :t8f avgi7b 7y$12 \; m/s$ to $25 \; m/s$ in 5.0 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 from4y0y-pclj3(j hdqy c:5 kg7uj $17 \; m/s$ to rest in a distance of 71 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach azg5te*y5t8o;t 7h jbwian q-(gxho6,- b7j jz speed of $33 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.9 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentiayr;o e3fyh/x (lly top speed abou r;of3(yeh/yx t $11.4 \; m/s$ in the first 14.8 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)  $s$

  A car slows down uni9u,j6 d9pgfuohhm2o/2 x .ocu gu+h4 vformly from a speed of $18 \; m/s$ to rest in 4.91 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 highway. Assuming wf2sw88w hst 3su2* tu)bfsw,a dec)2sw2sw3s bfwuw,t h 8s*f8uteleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck kqk.w-3pqm er be+.makc v)6epk* 72jgoing $25 \; m/s$ 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 30.0 min.r6ajc 97:jlstq w8 ka. After exactly 27.0 min, there are stil j jsr8.kawq79l6:cta l 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?    $s$