Suppose that an object travels from one point in space q1hf ac( y0(4nsv+ k7nno.h bbto another. Make a comparison between the diyk1+n bv s hq4.nb7(0hoanf (csplacement and the distance traveled.

  When is the average velocity of an object equal to the ep9;bz ze2h 6xinstantaneous velocity?

  A new car manufacturer advertises that their cac5hdi0n s;e oglq8oqenc-*4 9r can go "from zero to sixty in 8 s". This is a descriptioe; -5odcn94cnqg 8*s ilh0 qeon of

  An object moving in th)+vw ccv2iaaumr*g+ 0h5 gch *e +x axis 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 slow down as imm+2u5dnmix 6t approaches a traffic light. Mmdm+2u6im 5 nxake a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x d(b2e rv /hbx6virection) begins to slow down as it approaches a trev(v2hr 6bx b/affic light. Make a statement concerning its acceleration.

  Suppose that an object is moviny1 vo hj 5mjrr95ob:.ng with a constant velocity. Make a statement concerning its accelehy 9.5bjro1r5nj ovm:ration.

  If the velocity of an object is zer9 s m e0caxz4:.sq6wfro, does it mean that the acceleration is zero? Supporq0mw erc x9ss .f4a6z:t your answer with an example.

  Can an object's velocity change direction when its axi 2gwge6b6-xcceleration is constant? Support your answer with an w6bg x6 gxe-i2example.

  Suppose that an object is moving with constant acceleration. Make a statdb-pcfs ;29 sfement concerning its motion w-9b ds;pc2sffith respect to time.

  Can an object have increasing speed while its azl- )f+j xuyd3cceleration is decreasing? Support your answer with af+juyz- l)xd 3n example.

  Suppose a can, after an initial kick, mn+vfl 3ald 5:qoves up along a smooth hill of ice. Make a statement concernin5fa:dl3q +nlvg its acceleration.

  Under what condition is average velocity equal to the average on w;nxa2+y9 r,j4tssj f the object's initial ananw2nrtys; ,s 49+jjxd final velocity?

  Objects A and B both start at rest. They both accelerate at the scrbbk 6ii 8035q,m cjaame rate. However, object A accelerates for twice the time as object B. What is the final speed of object A compared to that of object 8imkrab3 jc,b6i0c5 q B?

  Objects A and B both start from rest. They both accelerate atc3q8w-5fyae f)a-)z e3 feurz the same rate. However, object A accelerates for twice the time as object B. Whaq z w-u rf)az3eea 35)-c8feyft is the distance traveled by object A compared to that of object B?

  When an object is released from rest and fallztfc1c,v kk)8s in the absence of friction, which of the following is true concernin8kktz cfc,v1 )g its motion?

  When an object is release8 1f kphj wx6jq (.gu(ngw3y:q8 t5jwid from rest and falls in the absence of friction, which of the followingxwju86k1 g3wfij(wj(y qh.:8gnqp5t is true concerning its motion?

  Suppose a ball is thrown straight up. Make a statement about the velocitd uxzjksh: mn;e*:j73y and the acceleration w; *sd3kx:h:j ume7z jnhen the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just m 8 npf5hb5o/wbefore it reaches its highest p8mbp /h5f5wnooint?

  Suppose a ball is thsny ac(k4p i k-5t ae3/q((mcbrown straight up, reaches a maximum height, then falls to its initial height. Make a statement abe 5n tcyim/c4- k(bk s(apqa3(out the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, t1uaao w :1qp 7uv)8; numk-rpqhen falls to its initial height. Make a statement about the direction of the velocitykuoq;wa18)-u vu qmpnr1 7 ap: and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of a -,qwd2 elh-bj6r5 sjair resistance. Make a statement concerqjad, 2w-hrlbesj5 -6ning its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her am(;h(.z oi exmcceleration when she she reaches terminal velzho;m . em((xiocity?

  A ball is thrown vertically upward 9i nnwi75ts)o with a speed 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 the first ball? (How many ti)9i 5wt7ns inomes higher does the second ball go than the first ball?)

  Ball A is dropped froqk*njh7; ud4qsm- z.j m the top of a building. One second later, ball B is dropped from the same building. As time progresses, the distance betwzj; -j.dhu7 4 qnkm*qseen them

  Ball A is dropped frv5vp3z u6 ,eu ll(v vvuj1cv*7om the top of a building. One second later, ball B is dropped from the same building. As time progresses, th 1,uluu*e7l5(v6vpjz3c vvvv e difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrh u +ifr*un1/ o9tjl,*l c., xktuc/iqown up, and the other is thrown down, both with the same initial speed. What are t,urouu.hil,i c x*k qtjct9f/nl 1*/+heir speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick (w 6lxfgg o+w+wo,zk5 is thrown straight down from the same building. They are released at the zgw6w+o l(, g+xwk5fo same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocityqj:ezl6y)p5t9pqc1msq i+ 1 u in the +x axis. The position versus time graph of this o yiq t1zu5epmsjq)p619+ lqc :bject is

  An object is moving with constant non-zero acceleration in the +x axis. ;n;f sc7 :xa+:gkjiitThe position versus time gxs fjiain;ct +7k;: :graph of this object is

  An object is moving with convl9v pywnvh-.7)n ia0(; 9c wzi nabw4stant non-zero velocity in the +x axis. The velocity versus time graph of 9 l7wv 49v (a.n;zwhwbvcpy ai nn0)-ithis object is

  An object is moving with constant non-zero acceleration in the +x axis. The pp2jat .pn4t5yxme ).velocity versus time graph of this object is2p5nppym.4).txt eaj

  The slope of a position versus time grp (x)vz, 3+iuz-fygiy lsr40laph gives

  The slope of a veloch 7-4e of;w whijm9mvw6fx: .hity versus time graph gives

  The area under a curve in an acceleration versus t: :wf hygj0:mwi(b ht+(nlu u9ime graph gives

  The area under a curve in a velocity versus time graph rd1yf440oi g/- tidnngives

  If the position versus t3hg0.kkf 9htl t n/fe6ime graph of an object is a horizontal line, the object i63 g lteh.tn/h0kk9ffs

  If the position versus time graphmb3sg;cq i.4v of an object is a vertical line, the object isgvq.;43bm cis

  If the velocity versus time graph of5g a3kb1/aq:l2tk2qny,r q6 qrtz) kj an object is a horizontal line, the object isa/ k) t32agl 61 qy2jkq,t nzrkr5qb:q

  If the velocity versus time graph of an object is a straight line making an ang12ufk9i(hc ru +p6g ccle of 30 1ccuc 6ri2(+fuhp9gk degrees with the time axis, the object is

  An object moves 15.0 m north and thenxh/; (dhglj+f 11.0 m south. Find both the distance traveled anhdj( +/ ;lfgxhd the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How longw2wx2e o9ar/ j will it take to move 12 km upstream in a river fl 2o rw9jex/2waowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = gbmb)yf 1- jmvbr:t6 -1609 m)

  What must be your average speed in ordm:4fb rcy0u1s er to travel 350 km in 5.15 h?

  A runner ran the marat/n 5pssm14 v1b5,t (upuz rxdthon (approximately 42.0 km) in 2 hours and 57 min. What is the average u,udvrn5pxt 15p41mssb(t/zspeed of the runner in m/s?

  A car travels 90 km/h.m*ilg1eik)dk)0 njm8 How long does it take for it to travel 400 km?

  A ly (light year) is trk9f45l ysnc (he distance that light travels in one year. The speed of 59ys (4cknl rflight 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 you look to the sidpmfotsr// t) n1,lbm5 e for 4.0 s, how far do you travel during this ina) ptbrlo1/ms mt5/f,nttentive period?

  If you run a complete lo-tfr 4j2ee ra+u* dcitaf*t9 6op around an outdoor track (400 m), in 100 s, your averag9u a ftt*d+jic -6e re*2ra4tfe velocity is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km eas8,o:a7/a lns93vu-bxzpzt p z t, then 1.0 km north, then 1.0 km west to return to its starting 7x,8sbpop u-9zza/at lz:nv3point. 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 soutca.w l* 7iax ly5.x/keipt2/ nhkts53 h, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes tp3 7xanh l2i.kaxkyt.l sc5* 5/wi/e 45 min. What was the bear's average velocity?

  You are driving home :3n.vz:zk. h*ckl)ik ( zlgxkon a weekend from school at 55 mi/h for 110 miles. It then starts to snow and you slow to 33:iczg.(lzkv.k k*hlkx n:)z5 mi/h. You arrive home 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 km/h. What is the averdg1e(k:*pnivt*1 qd zage speed of the motorist for thisk t peg*1di*1nqzd:(v trip?

  A motorist travels for 3.0 h at 80 km/*9 k0ctmxxyozl6,- *sk j ry(l ndp(0wh and 2.0 h at 100 km/h. What is her average speed w0k 9(yxz,yxn*l c0 k(odjs tml*p6-rfor the trip?

  An airplane travels at 300pd +o(:ex4a ym mi/h south for 2.00 h and then at 250 mi/h north for 750 miles.+ oyde(:4ap xm What is the average speed for the trip?

  In a 400-m relay race the anchorman (the :3fk sgd u .2kjpotf,+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 i .:updt sk+off,2k3 jgs 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 after 9 s. The car'lcf;dc( 4qwy- qq q8yif,+a6x fz;(ads average velocity during deceleration was 34 km/h. What wa8iaadx+f;cfy (w-;qyz4 ,l6d( qqq fcs the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average rate ofbbvx- ;dpks+ . soo7uf2 2xqv7 -s+s2bf b2pdxq7 v.oo vu7x k;$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerx/of hywx lp/g+58o q, je/hg9ates 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 a m*p;iisy3 9ka8 bnd4x-n3meiccelerates 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 -/ ltyz6f +q,2yvbq ri(v3wcm10 s. It then speeds up with a constant acceleration of cy il,f3v+(qz/t w -rq6v2bmy$2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 7.6 m/s experiences a constant j* -45 qb- blcv;l56u;udpjqjpzm7nyacceleration of nq6lubvmz;up 5-q*d5j bjp -l ;cy4 7j$2.2 \; m/s^2$. What is the cart's displacement during the first 5.0 s of its motion?

  A bullet moving horizontally to the rightfm*wl-(ucgq 77el+qq (+x direction) with a speed of 434 m/s strikes a sandbag and penetrates a distance of 96.56 cm. What is the average accele7w cqm f* -lqug7(ql+eration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched fro r2 wwi5esl37-t4binq m 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 con5e-iwwqr3s27binl 4tstant, what is the length of the catapult?

  A car starting from rest moves with 9i3ph38ywe xaconstant 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 1oa 88ik5tbhum. What is its average acceleration?8ih 1oua 8kb5t

  An object starts from rest and undergoes uniform accelerati cfwuu r4v a4;)9sqowa,/pp-pon. During the first second it aw,fu vp-q4;scu4a9 p/)pr owtravels 8.9 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initiallyxrddk 5k7c+6 p si*1 lsghz-0t it is traveling at 16 m/s. Three secondsip-zc571+0lr6 tx shg*ddkk s 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 tqe 6: i41pjmm$3.0 \; m/s^2$. 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 dece: +ew w7u c1 7jnhsdwwz:kpr35lerate 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 wainm4 p4i)jmle.vd oc*8 ting at the intersection starts ahead with a constant mc)jo84n ei*.vmlpd 4acceleration 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 plam.f eizq 2oj(p3x-*jknet X where the ac e2-mo*pz3k(jx qj.i fceleration 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 2ma ym /b u+)l2dk4 +:xd;qtnetjhl -ithe surface of planet X where h:k mmt lx) ydja/et2 qi4+b;n-2dul+the acceleration 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/bu4cm*bp:h 8- ooiy 0os on the surface of planet X where the acceleration due y*8m opuob-c4o0b h i: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 plangj5(ack8fa f;*pe8po) f8fv i et X where the acceleration due 8fivp egof88 5cfj;ak)p* af(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.8zg(.9x 5a mn1zjccyqbj0y5 g If your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fall before you q( mn01 8y5c5jgya czb.9xjzgcatch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its veloc2p we fts.ax9*d3j 0d( ;vkflcity after 3.02*pxsat lwfd3f(; jk c09.dv e0 s?

  A bullet shot straight up returns to its starting point in 13 s.* 7w 2f1iyuqng What is the initial speed of the bul7gwqi f 2y1*unlet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does it te0 ,yx ppnev40 gf , hsodj,8d3wsx).aake to ra)n80.xwdeg3sod0 pyxf ,phs j, 4ev,eturn to its starting point?

  A ball is thrown downward from thx)b0gbb. bv) de top of a building with an initial speed of 17 m/s. It strikes the ground after 4.8 s. How high isx.bv) 0b gdb)b the building?

  A ball is thrown straight up with a speed of 30 m/s. (onquiak y 5mr,s2/fx1j( ly fill in numerical value in theyj i2 sx 5ukmf,q/1ra( 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 straiz j vn)oqufh+m8/l2th+2mm+ )- zgcapght up into the air with a speed of 27.4 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 7 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 7.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at tex ;r6l.j qi equu8xkuyk 40:* = 1.0 s?

  In Fig. below, what is the vec hl0.zp qqy4+locity at t = 2.5 s?

  In Fig. below, what is the velopc1 6yjae j+mfp8i51ycity at t = 4.0 s?

  In Fig. below, what is the velocity at t = 5.56j*9nditd1 4zix/6rw cyw2m rwa19ow s?

  In Fig. below, what ;x em;y.0k iqeis the average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocitszesr8tl6,e7 :z yp;yy from 0 to 6.0 s?

  In Fig. below, what is the acceleration at 5wy;* nd/brhc2 fije/lw*ku -t::(kpt(oh zi 1.0 s?

  In Fig. below, what is the acceljcz5u)) fd6c feration at 3.0 s?

  In Fig. below, what is the average acceleration from l8v oj) qz plk.,09 5eyzw9n h3tm3iqj0 to 5.0 s?

  In Fig. below, what is th08zrdi 57ggwwck:ql: e average acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacemen 4 o8hci pcn48head6i1t from 0 to 8.0 s?

Does a car speedometer measure speed, velocitmnguorlt)8 a+p*1 ,i()9ekuhx jto yd94n4x ny? {speed|velocity}

  An object can have a vaa(74a pnegfrqz;s e 2iep2+3jrying speed if its velocity is constant.

  The velocity of an object can be negative when its accelhgdbgv s)m9 w)5a 7g2seration is positive.

  If one object has a greater speek.1k2xl n 3,y zjlpj0vd than a second object, the first must have a greater jyz.2 k1nj pl0 k3xl,vacceleration.

  Two cars emerge side by side from a tunnel. Car Adtd/al+ fmt9 8 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 inc.ui8f3i;lxb/1ers p yw/v) svreasing in speed as its acceleration decreases.

  A baseball player hits a foul ball straig,kht ivd,*55ereypu 8cw*h l4 ht up into the air. It leaves the bat with a speyr kpl i*v dh5*4h58ce,ute,w ed 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 itgo)zj,b3thm +iilx w n05 f1q8vqa*s2 s acceleration, how does it change if air friction is igno +q)fx*lia2oq8b,w 1jmhzvigt 53n0s red?

  As a freely falling object speeds up, what is happening to its accelerati v ;tud(g 07cezz/kyq-on, how does it change if air friction CANz( g7;zdy-ku/0etv q c NOT be ignored?

  An object that is thrown ve 24(zj57yubp;2 d w- vqxowecxrtically upward will return to its original position with the same speed as it had initially if air -ju2p (cbow z; e7x2 ydv4w5xqresistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocit85b shj8y6 )z5vaoxtgbj/n q7y and nonzero acceleration at the same time.

  An object can have nonzero velzhzf(i6) yw qen cs+jli7f471ocity and zero acceleration at the same time.

  An elevator moving from the sennud.b,j-y 4u. s-qx vf,he3bcond floor to the fifth floor making no stops along the way has zero acceleration all the time.4ejfu qb.x,s y nhnb-., dv-u3

  A rolling ball moves i :q 4xn0uftu61oc6ya from $x_1=2.0 \mathrm{~cm}$ to $x_2=-8.3 \mathrm{~cm}$ during the time from $t_1=2.2 \mathrm{~s}$ 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 $t_1=-2.2 \mathrm{~s}$ is at $x_1=2.2 \mathrm{~cm}$ and at $t_2=3.0 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete lapszm :zh u5ur(k ;q+hty0 around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 8.0 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, moving 1b/po ryox5e) (16 m away in 9.5 s. It then turns abruptly and gallops halfway back in 4.7 syorp(x5oeb )/. 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 frh0suz9/0 ywhu om $11 \; m/s$ to $22 \; m/s$ in 5.6 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 o an87r; (xrsjkfv0s:qcrf3+$16 \; m/s$ 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 spel1*aqdgs0q f iku. /(fa96to ued of $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.1 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks tom44bpmsli g+8l ist-* essentially top speed abouislb+g ml44 *itsm-8 pt $10.6 \; m/s$ in the first 12.2 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 from a spq6g d1mo80sc:8xus:: cjiy q iimn5m:/g e /ueeed of $15 \; m/s$ to rest in 5.93 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/mim gpdte x w;8w9wa1b6/+ds the highway. Assuming a deceleratipwb/a 9+tdei /81m;d s6mww gxon of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck l2zu;ne(4ioxd5z j q. 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).    $m$