Suppose that an object travels from one point xf;c hx t-r)pjh:x9nx t.h8w0in space to another. Make a comparison between the displacement and the distance traveled.h :xthtcx0r;8xwn9xf) hj -p.

  When is the average velocity of an object equal to6*zw:r(wei- r wt9o ld the instantaneous velocity?

  A new car manufacturer advertistm)hyz ,ggs5 *es that their car can go "from zero to sixty in 8 s". Thisz* y,)tmgs 5gh is a description of

  An object moving in the +xn8 a7l9 /)vy*ddn3wayyzeu:l m 6g4la axis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x d mjd-50kss z+nirection) begins to slow down as it apps+nj0zm -s dk5roaches a traffic light. Make a statement concerning its acceleration.

  Suppose that a car travel-n40j f; o:xeiit xqvow amac. t+z*:5ing to the West (-x direction) begins to slow down as it approacheq:t v.zfm t en0*x+ 5oai-jaocwix;:4 s a traffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make ynx:xrpv17x3wus-: m;:op4 s jsb:js a statement concerning o: :y sunx7s3psm4-jj xbr:p:x;w1s v its acceleration.

  If the velocity of an object is zero, does it mean that the acceleration is zerou0ytv072 koiw ? Support your 0y70iwv ok2tuanswer with an example.

  Can an object's velocity change direction when its acce1c dl,eytj9*it q9)f6j ujgx2leration is constant? Support your answef x1igce26l,9 )tyjujtd*9q jr with an example.

  Suppose that an object is moving with constan7/lu2 o 6qf u4pqxofu;t acceleration. Make a statement concerning its motion with respect t u72; xp uoffq/ol6q4uo time.

  Can an object have increasing speed while its acceleratiot0inlur7 tv h:s)0kw2n is decreasing? Support your answer with an exampl02k 7:0luihr s)wtt nve.

  Suppose a can, after an initial kick, moves up along a smooth hill of 2n3b;wstap a vg g*:c4ice. Make a statement concerning its accelerp4 cwaagt:s;2nv *b 3gation.

  Under what condition is average velocity equal to the average of the object's b/mzai; ri+v-i ax/b-initial and final vv ;i/xa- b- ibriam/+zelocity?

  Objects A and B both start at rest. Tpz q yuy70* j,u2maxtd ci0g-4hey both accelerate at the same rate. However, object A accelerates foxg u0 jyzq2p, cm-7ya 0*utid4r 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 at the same rad t27.l vvrd2dte. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared ttd2 l72dv v.rdo that of object B?

  When an object is released from rest and3s45no cn8quc falls in the absence of friction, which of the following is true concerning itqc5sc8 on 43uns motion?

  When an object is relznk--s *e:iz8pu3+hlqx b7vx eased from rest and falls in the absence of friction, which of the following is true concerning 8bkvilh- sz- z7*ux: enp3xq+its motion?

  Suppose a ball is thrown straigp5 g :425qz ev- mbzehmiw3ux2ht up. Make a statement about the velocity and the acceleration when the ball reaches thugm:h b3vze25 5p q m2-iwzx4ee highest point.

  Suppose a ball is thrown straight up. What is it h(ej88:4qnfzp5rki7 x2 hptus acceleration just before it reaches its highest pofkp xi782n(u8t pr: qjh5e zh4int?

  Suppose a ball is thrown straight up, reaches a maximum height, then fallow9u9l - d*2 rtbkbpc0s to its initial height. Make a statement about the direction o2pd -9c0kbtulbo*w r9 f the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reach7h( d1*(vif fj 7at;bt7ptmsbha b4jr+pe6m) es a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and accelebhm * rpa7 vejb ah7is ;tjf4mp()(tf7dt16+bration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a sz4ig;mludx :va- e:5r7k8xz otatement concerning its acceleration.-zilmed: :gku 4 ov57xa;rzx8

  Suppose a skydiver jumps from a high-flying plane. What is her accelerath0pfn/ 3hdsun: wf-u7ion when she she reaches terminal velochh n-wf 0pusn:d7u f3/ity?

  A ball is thrown vertically upward with a speed v. An identical second0gxajcyg15 v; 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 times higher does the second ball go than thcvg 0xa5; 1jyge first ball?)

  Ball A is dropped from the top of a building. One seconiwko*, ;c d4v i/vaslys-m85ld later, ball B is dropped from the same building. As t8viv-k/; 4ow * 5al dsil,symcime progresses, the distance between them

  Ball A is dropped from the top ofa1c;kw(:1:h5ry/ xprl cdjfnol6+bs a building. One second later, ball B is dropped from the same building. As time progresses, the difference in thecr nk 1:p5 1d/f:cbhl6ly ro+j(xaws ;ir speeds

  Two objects are thrown from the top of a tall building. One is thrown up, aj r4z fqbu*(won5)i/tj0sm3 tvt1f7h nd the other is thrown dowtr) tt7uj1bh0v53 q fjfizm(w/4nos* n, both with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A secon;ye 8p 4d.o 6krdetg*pd brick is thrown straight down from the same building. They are released at the same time. Negkote*pp 6d8e4;d g .rylect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant gz3w 8otbb69nnon-zero velocity in the +x axis. The position versus time graph of this objeg6 z9 obntb8w3ct is

  An object is moving with constant non-zero accelera. xbqtuve 8v2)tion in the +x axis. The position versus time gra.ex )qb8v2 tuvph of this object is

  An object is moving with constant non-zero velocity in ths 75wqte-2+pfajh(tce +x axis. The velocity versus time graphspwf het+jc(- 72t5aq of this object is

  An object is moving with constant non-zero acceleration in tny8qr )hej ,5fhe +x axis. The velocity versus time graph of this object isr8h) jnq e5fy,

  The slope of a position versus timou )a* pzct:n/2vcw i(e graph gives

  The slope of a velocity versus time graphj v:,skllyc* h7h,0ih gives

  The area under a curve in an acceleration vers s do l0xu2;*xq4e7zy iy2a*txbw*)y gus time graph gives

  The area under a curve in actvbr+7qt+)19 d5w t b7rtudk velocity versus time graph gives

  If the position versus time graph of an object is a horizontal l2jdddo4z q5t7 ine, the object idd7otj2dz 54q s

  If the position versus p*1j9 gj;a1ph9 qadfa-ig3i ntime graph of an object is a vertical line, the object isiafap9di-p 9* gq; han131j gj

  If the velocity versus time graph of an object is a horizontal linejb bs .lpyd(g* fgj18 y1f+t)p, the object is8j*djgt b.by l(g1fy)pf+ s 1p

  If the velocity versus tiurlbm 72 (kq1nme graph of an object is a straight line making an angle of 301bumk7 ( qnlr2 degrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both the distance trxpc tx i lk /:ag3s4/bxn:7x-faveled and the magnpt c/b-ka/:i3f xn gsxx x:l47itude of the displacement vector.

  A boat can move at 30 km/h in still water. How long.t/njl 8es/w 0m. vbmh will it take to move 12 km vse0hb. /j/.mn m w8tlupstream in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (a zb0,lr.i:m u,p,k/sd,q oj i1 mi = 1609 m)

  What must be your average szr 1yuu 8ti,hz vs9r01peed in order to travel 350 km in 5.15 h?

  A runner ran the mar/ x6rys3 l lffc).f9oj8v4uicathon (approximately 42.0 km) in 2 hours and 57 min. What is the average speed of the runner. 89 6c xf/olsrclvi)yu4j f3f in m/s?

  A car travels 90 km/h. How long does it take fxux1(z lcgzy/4 o2:i 7p2s; g2d wsnzfqde9s5or it to travel 400 km?

  A ly (light year) is the distance that ld/uhpim,5(/k4xxnx r ight travels in one year. The speed of light 45/m uxhxd,kx(nip r/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 st evbswp8;b8d1 raight road and you look to the side for 4.0 s, hop8b8;d s bev1ww far do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 1f*/ogv7 ln1gp dih 9lah2z8k 900 s, your average vf9gkl/idz 79hgpo1a8*nvh 2 l elocity is

  A polar bear starts at the North Pole. It travels 1.0 kw1w 2,dv3 tt ;mvskv0im south, then 1.0 km east, thenk2 d0i, v;vmvtts ww31 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the North Poleeridil+u6,i3r gc/qbay z/j)fp -fci5q38 f 0. It 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 was the bear's average veloq qb3c j6i lpa, )5ci-+0gfrd eiu8rf f/3iz/ycity?

  You are driving home on a weekend from school at 55 skk* rc /4 3ohd;cqf,fa+v g5kmi/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 hometown g5ff cvkq3o kc ,*/asd+ h4rk;from school?

  A motorist travels 160 km at 80 km/h an+sl *wkot3ps +d 160 km at 100 km/h. What is the average speed of the motoris+pol +s 3w*tkst for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her ave.m6/r)jetqhq+s ts h6 rage spe)6 m hh6.r t+/qesjtqsed for the trip?

  An airplane travels at 300 mi/h south for 2.03j/m/38x xadwu ,*t8nwnbzw d0 h and then at 250 mi/h north for 750 miles. z38xjwa /u*m3n/ dwnx8 db,wtWhat is the average speed for the trip?

  In a 400-m relay rack/z1 711x b7khgyfo ypbi8 8cne the anchorman (the person who runs 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 startspb1i k/ky1nfc78z1 ohy7x8 gb the final leg of the race, in order that the team A runner not lose the race?

  A car decelerates uniformly and comes to a94lq4otvi(b3tjo(u) uxo u 4q stop after 11 s. The car's average velocity during deceleration was 49i9bt4) qvxut4jolq oo(4 u3( u km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average wizv ;pcu(q96rate of 6v;cqi uw(zp 9$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h a7 .qgkre xq49occelerates 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 and accelerates ate 9yt8a0i rf*;7 9ruet4eozw wv,hxz : $4.0 \; m/s^2$ 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 fp,uzy j/h2 l no,r0bg6or 10 s. It then speeds up with a constant acceleration jrl ,z,o06gyn 2b/ph uof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 1.6 m/s experiences ara+ob4w e /n(84plzf z constant acceleration ofb4ew (plz/r4ao8n zf+ $4.4 \; m/s^2$. What is the cart's displacement during the first 9.9 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of 4233uy3pd/z y+h c m/s strikes a sandbag and penetrates az /yc3+y u3dph distance of 79.46 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on8 i e8*yo7(en wwcz3ri an aircraft carrier. It reaches a speed of 42 m/s at the end of tniw c7(z8e3r yw 8eo*ihe catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves wi(h. 5hpell qe 7b3ak3+7 7wdkirzid,ath 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 ith7to x e+c 8 1ost 7jf(+;1ftwp*el-pjuhv3dcs average accelerapuj3xjhpcfo;+f-7ewel* t 8sh1t v1+7 tod( ction?

  An object starts from rest and undergoes uniform acceleration. During the s 856ivipzj l*first second it travels 8.6 m. How far will it travel during the third secopv5 izsi jl68*nd?

  An object is moving in a straight line w )b/dw;x c9hr;ie1l lpith constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 ll/ ce;rw;h x1 pbdi9)m/s. How far does it move during this time?

  A car starts from rest and accele+1u uhrn-s*eq rates 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 ggj or*n:*zh7at 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 gre:5yiq6vv:y l soy1iiutb;2- een, a car that has been waiting at the intersection s:;:liyt5ebyisvq v y6i1u- 2 otarts 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 yms*+tr4 * l+umot8xq speed of 12 m/s on the surface of planet X where the acceleration due to gravity isq*m r yolmx4 u+8*t+ts $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12 m/s on the surface o4s fi,f8 2)ogdqx ;v ko;nzib:f planet X where the accelerationi ; ng;x)ik4oq2v b8fdz,so: f 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 with a speed of 15 m/s on the surface of ((st e4cg/nxyplanet X where the ayc xg tne(s/(4cceleration 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 plato c)c izw3y h4hz)y(:9ups* 6kr m6ymnet X where the acceleration due to gravi* )9m6 r)h (kzh6socyp:m yci3 zwyt4uty is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually greater than z inxuqy(o(sq*i+qro67b 5u7 0.10 s. If your friend holds a ruler between your fingers and releases it withoqoi(yqu (bxnri 7q o*+75us6 zut 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+78npur q7frunr/fa 4. ep;zz elocity after 3.00 ze;fu/unfnz.r 7ra8q+ p7 4pr s?

  A bullet shot straight up returns tfg3b(x tvjk5 b86vuu ;-t.qd oo its starting point in 10 s. What is the initial sjvo ;(6 f q. gt8kxu3-5bbduvtpeed of the bullet?

  A ball is thrown straight up with a sp r+jwjepjdaz.q +5+ b8 e- *2a0braafleed of 36.0 m/s. How long does it take to return ta r5e0p dew+.fajazj+j2b 8a rq+l-*b o its starting point?

  A ball is thrown downward from the top of a building with an initial speed o haoqgoc ./s:t3kykg3)xh5w 0f 27 m/s. It strikes the ground after 6.7 s. How high gs3)ckt 3oqh.okxy 5a/: gw0his the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numerical vae4llg y4 ae8ckk4d)p 6lkcepd4 4a lle 8gy)k46ue 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 g t;0xd*v jdj1kc uv,)speed of 34.0 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 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 isw 8h;l dtidn93 the velocity at t = 1.0 s?

  In Fig. below, what is the velocity at u 4s1fa ,:gky xw8g9gft = 2.5 s?

  In Fig. below, what is the velocv( bwna*d:eyg 8q5n( x ;lrov+ity at t = 4.0 s?

  In Fig. below, what is the ve) ewc,* wek)rllocity at t = 5.5 s?

  In Fig. below, what is the averagz w8 (jns/ufv1 spf;vw;+xkvj9ms w17 e velocity from 0 to 4.0 s?

  In Fig. below, what is the ave4g 5,84vpg8ikec8oz0isy (yqk e7tzorage velocity from 0 to 6.0 s?

  In Fig. below, what is the k0zvmxdjtynr9n);: jh1 g w,)(9q pzbacceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 wtw91awl)b;i s?

  In Fig. below, what is tr s0pdnm9o.4( xq5gfz he average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.n/ ; u k:6f/yxlbq+fbl0 s?

  In Fig. below, what is the displacement fo/npl0qb7gy,8+u .ji8oxzr 2dafi+ jrom 0 to 8.0 s?

Does a car speedometer measure speed, ve u nkk1zyxwrc30r 0 93qe.x:tuw8y0ou locity? {speed|velocity}

  An object can have a varyi5 :nx9fn3mbaf ng speed if its velocity is constant.

  The velocity of an object can be h j*x dl5f0d/x; 9yv8 k/6w-czqyjbu8t(ksmwnegative when its acceleration is positive.

  If one object has a greater speed than a sechn7:5o m0x bbeond object, the first must have a greater acceleratioxhb5 bm0n7:eon.

  Two cars emerge side by side from a tunnel. Car A is traveling with a speed of 8 *ka+qhif d) j9yw56wrduog.$60 \; km/h$ 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 incre yfibvk -croi89d-zk8,la.:aasing in speed as its acceleration decreases.

  A baseball player hits a foul ball straight up into t5ik *xf8 ;jmarhe air. It leaves the bat with a speed of r5*axkm;i8fj$120 \; km/h$. 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 vyq 2a* .grme;e,d x:vhappening to its acceleration, how does it change if air qey2ea;vrd*.vm , :g xfriction is ignored?

  As a freely falling object speeds up* 2etl4j0outhlzo:c 2m v2c1 m, what is happening to its acceleration, how 1t*2h0jmlvcm t2 co2eo:4 z ludoes it change if air friction CAN NOT be ignored?

  An object that is thrown vertically upward lpn 0d *n9zcsshly*(v2 1ucu5will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, hhs05 n u*9yn(pc *ud21vzscllow will this result be altered?

  An object can have zero velocity and n 8nhilwo5f.;))o-tistx2shu onzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at thehujwm+1qex ;2jkmyts- ym: xta(e +:2 same time.

  An elevator moving from the second floor+p-:gmuj* nqpfvev 9: to the fifth floor making no stops along the way has zero accm*gv pe :+nq:9pf uvj-eleration all the time.

  A rolling ball moves 2 :+pkleoca4 xqx1 *tkfrom $x_1=3.4 \mathrm{~cm}$ to $x_2=-4.4 \mathrm{~cm}$ during the time from $t_1=1.2 \mathrm{~s}$ to $t_2=5.6 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.7 \mathrm{~s}$ is at $x_1=2.0 \mathrm{~cm}$ and at $t_2=3.1 \mathrm{~s}$ is at $x_2=8.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-mile (*g3)u odusi; v$1 \; mile = 1609 \; m$) track in a total time of 6.2 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 strai/z: .weiwvm y/t fju(l e1:k,lght line, moving 107 m away in 13.8 s. It thl/v ky:wlm(,tiuj.f 1/ez e :wen turns abruptly and gallops halfway back in 4.5 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 fromnqevvyi h1dc5))w 4 r7 $12 \; m/s$ to $23 \; m/s$ in 4.4 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 fro3i.p(wule6)edt m/yi 8dg 9 kzm $18 \; m/s$ to rest in a distance of 80 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a shg4 ldk:urw;jr0 39sppeed of $33 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.8 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speed abou63gvro.55sb k9rq ku yk9v 5grk.s oq rby56u3t $10.7 \; m/s$ in the first 10.5 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 from a speed o,sdf7r/fj 2qi f $20 \; m/s$ to rest in 5.31 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m longd 5lt t8rb78dt on the highway. Assuming a decelera5t 7dl8dttr b8tion of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trqra9hlu,8sdy0 x*3*e pggd41o*ar qg uck 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).    $m$