Suppose that an object travels fockplr ; 3mn;o31hn xx, 8,oxrrom one point in space to another. Make a comparison 3 mnplnr rx8oh;o;c,kx 3x,1o between the displacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velbm zq (h0(* pdglo1fx7ocity?

  A new car manufacturer advertises that their car canv-lb;wrjp s3f ih.s;ww4-w1f go "from zero to sixty in 8 s". This is ab 1;vwwsl4ih;f3 wwsr fp j.-- description of

  An object moving in the +x axip2v 4t5 7+iz9gm+axcx.dwdd dx h)i*k s experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slowhxh a1wdm: 6m7u(c4g ji(o88tkn5f i g down as it approaches a traffic light. Make a statement conc84 i5howg1htxkj7 mimf a( c(ng8u:6derning its acceleration.

  Suppose that a car traveling to the West (-x direction) begml28d y9ylqea(ns, unak+j d6z n(9:dins to slow down as it approaches a traffic light. Make a statd8zl(9ul+ :y,na2jms nk ye q6d9n a(dement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a stag;a6f0lpol/ i tement concerning its accefp0/6og;all i leration.

  If the velocity of an object is zero, does it mean that ux,xy.l jo1.c+1dvbf the acceleration is zero? Support your answer with an examplfyvx.oc1l d+xu.1bj,e.

  Can an object's velocity change directio4rw(qn z :tek;k(fbj 9n when its acceleration is constant? Supporttb(:z9f;rq n w4 kje(k your answer with an example.

  Suppose that an object is moving with constant acceleration / 4wv1ak,r/jiwcl s2pl p3s*k. Make a statement concerning its motion /2v,*j3sps lri wp4/alc 1kwk with respect to time.

  Can an object have increasing speed while its1 lzm,e:jxsjxvw-;q 9 acceleration is decreasing? Suppoj1jxswe xzvm -:l 9,q;rt your answer with an example.

  Suppose a can, after an initial kick, moves up ivmj:a vx+q s/h:8q7 vt.rij: 3x t8dvalong a smooth hill of ice. Make a stat:rvxm:tijx+h jv tviq887.: qsadv /3ement concerning its acceleration.

  Under what condition is average 4g4, l9w shxmex-wm .jj(erv; velocity equal to the average of the object's initial and final veloc-mwr jx4 j,hxl4 eswg;m9e v(.ity?

  Objects A and B both start at rest. Theear5kj.)zb de*c 0 i9ky both accelerate at the same rate. However, object A accelerates for twice9r ze) .k 50jaiec*kbd the time as object B. What is the final speed of object A compared to that of object B?

  Objects A and B both s-d4sfr3zzv5vvm 1hpy )t*1y- ptu 4 mktart from rest. They both accelerate at the same rate. However, object A accelerates for twi zku)fpy-13 t4r- s ymvtv1d5 v4pzm*hce 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 ad*n ;5rp j2sxxv(2ifdb/ cd-qbsence of friction, which of the following is true concerning it /*rq iv2-(jnx sp2db;dx5cdfs motion?

  When an object is released from rest an nvb8--c )zmwnd falls in the absence of friction, which of the following is true concerning v-mzw8cnb -) nits motion?

  Suppose a ball is thrown straigxgkk3xn5cgz js2 );:u ht up. Make a statement about the velocity and the accele)z:k 5xj2xugn;skg 3 cration when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is ip(,y )n 5eczupr m36msts acceleration just before it reaches its h ,p ryescpnu(3mm)65 zighest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then falls to iz- hjg0rij33 (wm7wu 4h7yau(7f fhsfh +uy6lts initial height. Make a statemejfg (h(yh amhuulw+ufy7sh7jr-z3 07 w64 fi 3nt about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum hkx**unxsm4h 1 eight, then falls to its initial height. Make a m xn4*k* sux1hstatement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resfn; 8g: kx oyuec,n4582hbufm-7 gljkistance. Make a statement concerni, efbk:u5l;ynk8f h7gom x8cu4 -2njgng its acceleration.

  Suppose a skydiver jumps from f . zv6vlfozg)z )nk.(a high-flying plane. What is her acceleration when she .gzfo6z).l)kv vzn (f she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An iden)wn1ck,(joyj tical 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 the first ball? (How many time c,k1n (jjo)yws higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One sects7arxgw 1u(1 ond later, ball B is dropped from the same building. As time progresses, the distance between the 1raxuw17 (gtsm

  Ball A is dropped from the top of a buildibg 7ze5q ub3yxl155wofko 7l8ng. One second later, ball B is dropped from the same building. As time progresses, the537 fx1g5lqb 7yob5w zeokl8u difference in their speeds

  Two objects are thrown from the top of a tall buildi8 /ap jnlanf;ht55w3yng. One is thrown up, and the other is thrown down, both with the same initial speed. Whaa a5/5 lnft3 phnw8yj;t are their speeds when they hit the street?

  A brick is dropped from the top of a building. c6m:4yr)otso zs au8 v,ni.+q A second brick is thrown straight down from the same building. They are released at the same time.,m)a46vt.ir ocz qun8+ss:oy Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving 9q 1puj w2j,xhz-g8suwith constant non-zero velocity in the +x axis. The position versus time graph of this oz2wh ,up8x9uj gs1jq-bject is

  An object is moving with constant non-zv2mm/owg 5.m;/.; ;q tfbkydaj gswx8ero acceleration in the +x axis. The position versus time gdko mb2stx;m; 5agy/fw ; mvjw..q8 /graph of this object is

  An object is moving with constant non-zero vetkj:4 k bjxe(ps;5ei7locity in the +x axis. The velocity versus time graph of this objec54e (7;jp s:xbekkji tt is

  An object is moving with :+ml+bvhk manukt8 8)constant non-zero acceleration in the +x axis. The velocityvhk+ +tlm)8au mn:kb8 versus time graph of this object is

  The slope of a position versus time graph giv -rycr/blb k2f 4kv q2p:m9ga*es

  The slope of a velocitywce qk:;hfm 62 ;d-tdl versus time graph gives

  The area under a cur y.lr bn7o;fb(ve in an acceleration versus time graph gives

  The area under a curvy+q c +wmla-8re in a velocity versus time graph gives

  If the position versus time graph of an object is a horizontal line, the ob3 u,8y6k lzhvcy:w 2riject yizk :3u, 2 lvrwy86hcis

  If the position versus time graph of an object is a vertical line, the jv*w w*efz0e: i9; ii*q)jsee*/ xueb object is*w/jes :ejxwi0bie* u) *i*eze;9fqv

  If the velocity versus time graph of an object is uf *;q-ueakr+y )o /wz;ls8i+l1cysba horizontal line, the object -b /+wrzf8;uae +;i1qyco*sul kyl s) is

  If the velocity versus time graph of an object is a strai,xwfyny;y .7s-uvh j9ght line making an angle of 30 degrees with the time axis, the objecth-nu vw7,; xjy9f s.yy is

  An object moves 15.0 m north and thel lm sh or+(+oohnn2-kb-5y9 jgtsn :6n 11.0 m south. Find both the distance traveled and the l+snsot 6y9 n2jo-5ohkb:mhr-lg ( +nmagnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will imwb;humq1o)p fa v+qipz p ba820m5 eu6;u18ft take to move 12 km upstream in a rive81;mma82e uu a p;ifq51w +qzhmbf0p6v uo pb)r flowing 6.0 km/h?

  55 mi/h is how many m/s? (ke+ r4x m8eawkpj()- x4dwo+d1 mi = 1609 m)

  What must be your average speed in order to travel 350 km in *lqj7j7,kmnj),ydiv 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. What xvn3bhq6x 6. dis the average speed of 6vxb.dqnhx 63 the runner in m/s?

  A car travels 90 km/h. He)x ,9pxh4e ,nui)p gnow long does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one y7c8 mxvgy2y . uef4w9kear. The speed of light is 9 v.8ef4wg7yycmu 2xk $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 7my :)xmo*qc7 u2 km/h along a straight road and you look to the side for 4.0 s, how far do you 7mq) y o*ux:mctravel during this inattentive period?

  If you run a complete loop around an outdoor trac.jyn:jlygs16 k (400 m), in 100 s, your average velocit6:jg ny1j.sly y is

  A polar bear starts at the North Pole. It travels 1.0 km sou0i-)b lgxyqh7 th, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. lghq x0by7) i-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 south, then 1.0 km easpfobwjoeuoi( :: cy3:q59v8+ s v ojv0t, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. What was the beauv+09jeo:v:j8oqywp :( 5obsvf3 oicr's average velocity?

  You are driving home on a weekend fru1 y8a.wgm 4hjom school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive homma4ygj.81h u we after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 kmzoja(y5 qn j70qjw(5g/h. What is the average speed of the motori5j jw(zq(aj7g0 noyq5st for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is herth8 (mgp.1 z(fiq t1 +vh ukhgj*0sv2b average speed for the t2 h+1k8s ztmf1h t*i(j vughg(vbpq0 .rip?

  An airplane travels at 300 mi/h soutrolpiq9.+b7d wl6( huh for 2.00 h and then at 250 mi/h north for 750 miles. What is the average speed for the trhql7 l r d.uoip6w(9+bip?

  In a 400-m relay race the anchorwj)xplr) w;f7man (the person who runs the last 100 m) for team A can run 100 m in 9.8 s. His rival, the an);j )pr wxf7wlchorman 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 team A runner not lose the race?

  A car decelerates uniformly and comes to a stop 4.(ugsg m-3cwz ;zca6w +iwzsafter 9 s. The car's average velocity during deceleration was 48 km/h. What was the car's deceleration while slss+- zw (g g6wcu ;a3ic4w.zzmowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at gy-wp 0c-c3dq the average rate of 3 cyp-qgwc- d0$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the ratxm6.3 pc sc+;*j2txzxzz5 xms l04pije 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 accelerates al5)zsfl8* wii t $4.0 \; m/s^2$ 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. 387i6*,z +zvb opk(ai. tnc eaxwp1rqIt then speeds up with a constant acceleration ofzt3qa7xo iivw (*abkp6nrc,pz + 8.e1 $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 2.2 m/s experiences a constant acceleratie1 tq0s5 amqu qf(2xg/on of q50utq(f2x1 seg/aq m$1.3 \; m/s^2$. What is the cart's displacement during the first 6.1 s of its motion?

  A bullet moving horizontally to the rifh323t.wc( bwe,96n ry,sk- xutktl pght (+x direction) with a speed of 330 m/s strikes a sandbag and pcu 3.,6xk spk(f en,l9ttt2-wy 3brh wenetrates a distance of 43.18 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carrierw)u1n.(bqlmumim7 * t . 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, wt wu l7mnbu (im.1)*qmhat is the length of the catapult?

  A car starting from rest moves d:uon96vfj (cu+z;goadgl- 6 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 distpedl fx:c uc6j5dn4* -ance of 200 m. What is its average acceleratio-ncxfd4:5d pc e*jul6n?

  An object starts from rest and undergoes uniform acceleration. Duriec)o xzy8yx* l)9b5t qng the first second it o5y b lcz9q*x xe))t8ytravels 5.3 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initially itbh .n4f7;ps9d+ vzx bs is z.b bh s;f4+97dvpnsxtraveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates uniformly at ma8mp7 bo c:s((*8ml6j mxswh $3.0 \; m/s^2$. 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 7fh(,lr m j, 1aulvif/on a dry road 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 be fh :( m,4ko9c+mtoydqen waiting at the io,tmq:9 c(m y4dkfoh+ntersection starts ahead with a 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 plan n46xh2v3ibehsq) c :set X whe6)2x3i s: hqvsn4ehcb re the acceleration 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 m/s on the surface of planet X wh2 s41 s/x d:z1ygtmgtkere the acceleration due to gravity is /s t ktmdg 4g1s:zx12y$1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

  An object is thrown upward with a speefh21a 7g p1yjpd of 15 m/s on the surface of planet X where thahg1p 2 f71jype 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 surface of 0 0d0jf)ydlc;m :moqd planet X where thd;) lfy:0cqdmjd 0om0e 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 usually greater t +oaimx c14;akhan 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can you exp+ ca4xa1; mikoect the ruler to fall before you catch it?

  A ball is thrown upward at a velocc 9hd/m.aflv4imj-z h0x/gn j58n1ad :/ oxxcity of 19.6 m/s. What is its velocity after 3.00 s 01/v fzdchja/ xdxj .589a 4 onmin-hlxm:g/c?

  A bullet shot straight up returns to its startingmc8c tz(uz8q5w tq )5y5hx2og point in 8 s. What is the initial spe8c 5mz)tcq(ytwxoh55 uzq28g ed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How lopc2zzqmb.8nh ., c de2ng does it take to z ,m.z bq8cne2cd ph2.return to its starting point?

  A ball is thrown downward from the top of a building with an inititqao+av 4*mb bl0s8 )mal speed of 11 m/s. It strikes the 8 mav)boa0q4 sbt*m +lground after 5.3 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (on.ezmp(hml do,b y5j6:ly fill in numerical val6 mzh, :djyem(pob.l5 ue in 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 up into the air with a spe+z py +)pypjn1ed of 42.7 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 14 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 14.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity cbcr5x7j7 9 yttnf0d0at t = 1.0 s?

  In Fig. below, what is the vran2p-egv -3 n(coa9 yelocity at t = 2.5 s?

  In Fig. below, what is the velocity at tgn -:ohwl:db :;lbz9e = 4.0 s?

  In Fig. below, what is nyh:xf h (ift 73sso,2the velocity at t = 5.5 s?

  In Fig. below, what * o(y hjwigc .*1b8aldis the average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity from 0 to :(bfgzfj.7iw3(l/i wni3prm sh *)bp6.0 s?

  In Fig. below, what is th(,hbaup3tdzh cveo/2kv (i++e acceleration at 1.0 s?

  In Fig. below, what is the acce8+qthhf9**eos1e -rg) rk pea leration at 3.0 s?

  In Fig. below, what is tv *y1oxqu j fecv-rg+xe65 2+yhe average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to492 bc kbvh+ji 8.0 s?

  In Fig. below, what is the displacement from 0 lw8pjs0gw/1qw5 aqu0 to 8.0 s?

Does a car speedometer measure speed, velocity? {spv 3l-yg25bhe keed|velocity}

  An object can have a varying speed ifepk j.5cp 8 s4k) git4zh+-ns ma7bt9n its velocity is constant.

  The velocity of an objxt,tn i39wngixfv0. 1;k d+orect can be negative when its acceleration is positive.

  If one object has a greater speed than a second object, the first must have a grk+g-a9b tpr/yt+)ht t yapb)+ht+r t/k-t9tg eater acceleration.

  Two cars emerge side by side from a tunnel. Car A is traveling with a8df7 o7,8f+h u0yon gd7wi:yusjy( nl 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 increasingz(bg ;u, lldp1 in speed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It lea,fpe48gmbw)u 83b- e( aorx0nnqh0 seves the bat with nbpwemuehfar0s0 q8eoxgnb,-3 48) (a speed 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 speeds up, what is happening to its acceleratwhl/- kmx vdsoj7 j2lq* (x:(bion, how does it change if air friction is i x /7-ok(2vlq:m b dj*swhjx(lgnored?

  As a freely falling object speeds up, what is happening to its acceleratio-;;:t ecbcvknn, how does it k-ctne; cb:;vchange if air friction CAN NOT be ignored?

  An object that is thrown vertically upward will return to its original p-i0gane,+*+onqf yq+ 9iy vykosition with the same speed as it had initially if air resistanceigqn+kye *9 0a+o nqv,fiy+y- is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero jo)n7;c naw x/bc(kb gre608hvelocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and 6w* runf d-j5slqz36kzero acceleration at the same time.

  An elevator moving from the s ;e jwik3k1j );so:iobecond floor to the fifth floor making no stops along the wa;1:w 3sobej ) ;iokijky has zero acceleration all the time.

  A rolling ball moves fromm:i 2 tle 9za -i1n(bdtfja;0l $x_1=3.1 \mathrm{~cm}$ to $x_2=-7.8 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ to $t_2=5.0 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.5 \mathrm{~s}$ is at $x_1=2.8 \mathrm{~cm}$ and at $t_2=4.0 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a elu;l;;rn93+pgwf-5 nl+lg2 v voo76bp wuzg quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 6.9 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 ) je9xdf x x;vkg,o7(x6ll+ ln93 m away in 13.6 s. It then turns abruptly and gallops halfway back in 4.5 s. Calculate (a) its average spee fn,exxxvl; 7 k96d(l+j)golxd  (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 fr :f8j 4r 2g*di,qg kkxq+jc:oiom $11 \; m/s$ to $22 \; m/s$ in 4.5 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 x*4d0cp ;cfhb;9h i+isq/ hhf$21 \; m/s$ 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 s l29457esj3wzbfqk tlpeed of $27 \; m/s$ 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 speec i73beqis+znw *qczh, 2 4f9md aboutcc 7qs9 *iwhnq4izz 23 f,m+be $10.2 \; m/s$ in the first 11.3 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 unifqvu*cydr)8 ybbula7(jq65fbo a.6z y6;7 orw ormly from a speed of $18 \; m/s$ to rest in 4.29 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. Assuminu/g28dwh*rls c+ bk -eg a deceleratig2b *uks-8/l c+eh dwron of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truc;enb- y;2zm1k3lk r,.l nz wzhk 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).    $m$