Suppose that an object travels from one point in spf m6 xz;hgf6g5ace to another. Make a compa;m5 z66fhggxfrison between the displacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velocity5+ ep3osqijb b)g4 -kp?

  A new car manufacturer2;2;da9mtwhegqe7kcyrr2*y/ hr t3 w advertises that their car can go "from zero to sixty in 8 s". This is a descript22eeqrdhya;;wkr t3c9gr y/m t7w h *2ion of

  An object moving in the +x axis experiences an acceleratf7giq 2le.u4 wion of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveams*8,t)uir fling to the East (+x direction) begins to slow down as it approaches a traffic light. Make a statement conci,t)f* u8a srmerning its acceleration.

  Suppose that a car traveling to the West (-x direction) bekv xrn+0wdy1gah9m, ac , 0d+kgins to slow down as it approaches a traffic light. Make a statement concerning its accelhxk+w09cyav+dam, r,0d g 1kneration.

  Suppose that an object is moving with a const/eg.s-ooa l;zg+d1 fpant velocity. Make a statement concerning its acceos.dl/ of-pg+g ;az1 eleration.

  If the velocity of an objecg.u4kgmdeyt4s32 d3i6 wdwm 3 t is zero, does it mean that the acceleration is zero? Support your answer with an d423mggde3yk uw4s6m3wt.idexample.

  Can an object's velocity change direction when itsw, lgrg9 uruf4;v-nxcn(*ge+ acceleration is constant? Support your answx ,wenr+9ggugfv;nr-4cl(* uer with an example.

  Suppose that an object is moving with constant accelulyh z.*3ofc3eration. Make a statement concerning its motion wiol.cu3 yhz3f*th respect to time.

  Can an object have ix -p6t0k2tgd0 mztm/s ncreasing speed while its acceleration is decreasing? Support your answ2kx0s mzm6 t0t/dtp-g er with an example.

  Suppose a can, after an ini j(ym9 0djon8o4e6c hitial kick, moves up along a smooth hill of ice. Make a statement concerning its accnh6c 98jyjeo0 oi 4d(meleration.

  Under what condition is average velocity equal to the average of the object'shsbv; kmb :l.. initial and fbh .sl .k;vbm:inal velocity?

  Objects A and B both start at rest. They both accelerate at the same esfo:lsbzk0 p,* u e8+rate. However, objectl+8us f bzs oeek*0p:, A accelerates for 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 ratewh-3/vhlm7:cgsc:i af4 m 4 nn. However, object A accelerates for twice the time as object B. What 4l4mw:hacn- mh f gc/v:s3ni7 is the distance traveled by object A compared to that of object B?

  When an object is rel - 5d zlqn.zwqnr:;2yjeased from rest and falls in the absence of friction, which of the following is true concerning its motio rylzq5-nqwzj2d;n.:n?

  When an object is released from rest and falls in the absence of frifbcs)8j6uq t:ction, which of the followin6tfj u:qb8s) cg is true concerning its motion?

  Suppose a ball is thrown straight up. Makeb3 tc 7+q ,8qzw83qarrl4mfgz a statement about the velocity and the acceleration wher8wz 37g 8mc3+z,q 4qfqrlbatn the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just befa5j ;1jlpay/fore it r5aj1jl/pay;f eaches its highest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then falls twto*kh+j7fsb;0 ua/ to its initial height. Make a statement about the direction of the velocity a7;hkuwb0a tso*/ fjt+ nd acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to itsmy5lqrh 5h0; v initial height. Make a statement about the directq;5 r5 hlm0vhyion of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a2q2o pg6don 7g statement concerning its accelnpo 27 g2d6qogeration.

  Suppose a skydiver jumps from a high-fly(8rmo ll5 pul*8 gjk0aing plane. What is her acceleration when she she reaches teog5jr*m0l l(8 8alu kprminal velocity?

  A ball is thrown vertically upward with a speed 9g koxm-yy-b4o( jy(r v. An identical second ball is thrown upward with a sp 94 -kyrybm(ojg- oy(xeed 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 the first ball?)

  Ball A is dropped from the top of a building. One second later, b lgft+/0+ xom3x20ulhtb+ ngball B is dropped from the same building. As time progress3t+t++xgxhmo bf 2nl0l0bug/es, the distance between them

  Ball A is dropped from the top of a building. One second later, ball B is ehyw eh3:2q )zdropped from the same building. As time progressehe)w 3qhze 2y:s, the difference in their speeds

  Two objects are thrown from the tk- jd2evg;e i*op of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hek-e2jd vig*;it the street?

  A brick is dropped from t 1t(eowfb-9n .4hautnxu9,/ 0zs qpld he top of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neu1qw4dh.,e -tnzu 9 p/obl9(sx ft an0glect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The p)6wpc1 tdtlv)osition versus time graph of this obj6tv1)lcpdtw) ect is

  An object is moving with constant non-zero accel8nmigdq17j3 -layr-e3g(bb meration in the +x axis. The positm37grn ba 1gmd(j lie8 qb3y--ion versus time graph of this object is

  An object is moving with constant non-zero velocity zzje1;bhs j3kpv n)94in the +x axis. The velocity versus time graph 39jb4zne )vkpjhzs; 1of this object is

  An object is moving with constant non-zero acceleration in:1s* g(1ggbt hnspve: the +x axis. The velocity versu gh pesgvgbs1::t*1 n(s time graph of this object is

  The slope of a position versus tihu3++ rhfu ib.me graph gives

  The slope of a velocity versus time graph givs6 y anjj1w; hpdhap* h45 i*,x4g0gbaes

  The area under a curve in an acceleration versus tim ff3e4i5wa9l d *rrww6e graph gives

  The area under a curve in a vez , 7o6aple*rdlocity versus time graph gives

  If the position versus time graph of an object is a sc;z,hlc(5+oaz k6 t4z f2 z n(dqwf9jhorizontal line, the object ;htswd(l26(o5qzz,k zfc4 nfjc+ a9zis

  If the position versus time graph of an object is a vej)+fyt a9)su6a bh(dbrtical line, the object istj +)bya ad6u h(b)sf9

  If the velocity versus time graph of an object is a horizon (uz w39pflda) z*2fwital line, the object i zlu f) wa2p(dwz3if9*s

  If the velocity versus time graph of an object is as t,p3sgj+z. a straight line making an angle of 30 detja z s.+3,sgpgrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. n;sqh4 s ni7jpe.(9mc Find both the distance traveled ms9(niq ; 7s4ec.npjh and the magnitude of the displacement vector.

  A boat can move at 30 kzrxh asm;6qj5 ;g3 l+dm/h in still water. How long will it take to move 12 km upstz+qs 5h;;a dxjmrl3g6ream in a river flowing 6.0 km/h?

  55 mi/h is how many go0xwelhv 8w wv5zngmj4gy5e .+3 b9 ;m/s? (1 mi = 1609 m)

  What must be your average speed in order to traat7ms nk)6hgn.k)w*d . d+ops vel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) ibooh8 izis/4 u+h n:eg635 :vthczb1rn 2 hours and 57 min. What is the average speed of the +r:ibn:o5bhug8i/s3v4t z1e hohz6 crunner in m/s?

  A car travels 90 km/h. How long d jbuu6hwh(4 qvc.uie4/1r7cqu t5s y)oes it take for it to travel 400 km?

  A ly (light year) is the dbh*k1l :*nx5g vxkwo:istance that light travels in one year. The speed of ligh*o5:kbgxwh *n lxk1:vt 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,r,qyw-nuz ) tp.b p4x to the side for 4.0 sw,n btpzq -).xru4,p y, how far do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 nn2)((st5grku bfm7ws, your average velocgu7s f trnb (n5w()k2mity is

  A polar bear starts at the North Pol2/phcw zg4gw v/d.7gte. 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 spehvwg.gczd4 / 27wg tp/ed?

  A polar bear starts at the North Pole.-myh.u2a/0fyhdfa 3ub l1q ltf y+9i3 It travels 1.0 km south, then 1.0 km east, then 1.0 km dhyfqf l0 ytu9ya ba.2mfl-/3 i+u13 hnorth, then 1.0 km west 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 559zymhd)wcfwo 7g-(j g2 7f-qc j.ls 8w 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 your hometown from sdf y j77m2.hs9- qc-w(z)ow gl8wfjcgchool?

  A motorist travels 160 km at 80 km/h and 160 km ud r2 /ylth47dat 100 km/h. What is the average speed of the motorist fot/u2y4drl hd 7r this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is hou 42cl458y jlikw5c her average speed for tc 4k hyl 2o485lucwji5he trip?

  An airplane travels at 300 mi/h south for 2.00 h andub m/rc:2lbp,/ :x bkp then at 250 mi/h north for 750 miles. What is the average speed f:pc2bb,ml/ /rxbk :u por the trip?

  In a 400-m relay race the anchorman (th,yd v6v ;vfrmm z1vpd//(hvw( e person who runs the last 100 m) for team A can run 100 m in 9.8 s. His rivhyd/z,/1;mv pvd6v rv (w vmf(al, 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 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 2(pkfqp8:my:.a mijr yn*a0bn q*jx5car's average velocity durfqykrj* m (5m2np.*ap:y :8n0xajibq ing deceleration was 64 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 rated)9ygqqj3 -d-9ijmigy 8 t9tw of -ydym98)w3igdtq9- i qg9j jt$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rc5hb2 hw phk.;d1 tt(nate 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 atscp)ob w 5bt/( $4.0 \; m/s^2$ 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 (n8 z3k-kdl zm7lo. uyv*ff *l8rr7 cfa constant acceleration z(-n.7* lmvkdr7cz oyu l*8 lrf38ffkof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial neb:7h2*ts k76jb10 o cefhc zvelocity of 4.7 m/s experiences a constant acceleration o1kbenc2 sjtf7c6 z:o eb0 *7hhf $1.0 \; m/s^2$. What is the cart's displacement during the first 9.7 s of its motion?

  A bullet moving horizontally to the right (+x direction) with w 8m s1lhak,7bz77 gp :t.lwala speed of 287 m/s strikes a sandbag and penetrates a distance of 79.28 cm. What is the average acceleration, in 7h wsza 7ktg.l7 lp:w1,lab8m $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an a.kk/aih*b** hy4g ytqd.meoif.h9 1xircraft carrier. It reaches a speed of 42 m/s at the etb1f. 4*. 9ko* xgh.hdy ykqahemi*/ ind of the 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 with conzdts6/w-y e6m,moi ic3 vkor9,bol7 g-h1s8z stant 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 tco5w +q,3 exvn0.dvh9 mj-ez kfxii;,o 80 m/s in a distance of 200 m. What is its average accele 3z+, o0dxfj ;k5mxew- iqe9v, ih.cnvration?

  An object starts from rest and undergoes uniform acceler)am:.ph59oqdmcexwjk ihk4.f0 41dx ation. During the first second it travels 4.7 m. How1k.aohqhkix: d)pmc 50.jmewxd449 f far will it travel during the third second?

  An object is moving in a straight line with const/l: p,f mdst0px;xch/ant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How p hxpl0s ;:,x/dt/fmcfar does it move during this time?

  A car starts from rest anhdo azwaw1; wr26v 6t wy5fh+pf2.s3ad 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 road can decelw,22h qj4xl-ojo/ nb jerate 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 waiting at siw(7w ahqt)brro -:14t3pbf wf ;/jlthe intersectif3r(o-t / lw 1afwwp7rib ;j h4b:sq)ton 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 d*euy-a1st0x speed of 12 m/s on the surface of planet X where the acceleration d1*yd stx0ea-uue 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 ns+y lt8rn4/j1+ qsbcX where the acc4nbcrlys+1+j st 8q/n eleration 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 v 0((30e rmyei idyw7h tuk3m8surface of planet X where the accelerati ymi0e3d8vh(3m(w0uyke r7 tion 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 pv /du; j:aooij(3 emq:lanet X where the acceleration due to::ve; mjid/ q j(oa3ou gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually greater thamry( r6 njyr/;g1.ah q9r8hn/ hfca j/n 0.10 s. 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 ra1(rhng8 y/rjh9r c6/fyn;hj.ma/q catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its vel9.2kzf8 ucmcpvd jq /3 )ftn.wocity after 3.00. /n8uft)2jz3cfp cw km9qd.v s?

  A bullet shot straight up returns to its starting point in 19 ve1u0zhlou 5( s. What is the initial speed of0o(uh5 vl1ue z the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does it take bw4i( m3gudipxi,*9 g to return to its starting gbpi( g9,di*umw4x 3ipoint?

  A ball is thrown downward from the tojh)7 vv,3c8wiesnxb5p of a building with an initial speed of 12 m/s. It strikess7j)ec 5wx8i3n, h vvb the ground after 1.1 s. How high is the building?

  A ball is thrown straighcv2 ;erx qnt vm006tz3t up with a speed of 30 m/s. (only fill in numerical value in the;tv0qzc exn0m3rv62 t 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 o.ih) tyxp3z d-6m s7),/)p rpfwxlqcwith a speed of 43.7 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 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 s3:waeb.8sjbl9 y7we n:ebd + the velocity at t = 1.0 s?

  In Fig. below, what is the velocity at t = 2.5 s?z6xgzm) .2 snx/85dqx0wbmly

  In Fig. below, what isabhwric)* ::qtzp , /j the velocity at t = 4.0 s?

  In Fig. below, what is the tg -p hl:f)+(ik-pf3ax f pdk2velocity at t = 5.5 s?

  In Fig. below, what is the average veloci(h,-+ngcrgy5 h. zwtity from 0 to 4.0 s?

  In Fig. below, what is the average velocity from 0djvur+:4 2mav to 6.0 s?

  In Fig. below, what is the acceleration lelpkyr67v g/,dzb 83at 1.0 s?

  In Fig. below, what is the acceleration at i1fcydg ;865n7lgu6 pf5iqq)krol2r 3.0 s?

  In Fig. below, what is the average accelu 5/,yociwr,- un l-ret9x1qxeration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.0 s?q*lv/7w y +xxl

  In Fig. below, what is the displacement from 0 j,qha:ywc wl66c 6h: uto 8.0 s?

Does a car speedometer measure speed, velocit1.3kl37)c8cypeerlo ;cvj2 qtij 5by. 8 odoty? {speed|velocity}

  An object can have a vary*ut0*vyp8z p *xv uv:ging speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration y0eb0 z q1d90qtm5 dgfis positive.

  If one object has a greater speed than at;8qr)z-cha s second object, the first must have a greaterz;-sat )r8c hq acceleration.

  Two cars emerge side by side from a tunnel. Car A is 8iyx7 s)2nojbv:(z . +elpf qitraveling 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 t w5 nrf mjgrutj-5gg*(q/n-)its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It leavqf9 u8jlpn; 47-xgjtbes the bat with a spej-bqj9upxgnt 8 l7f ;4ed 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, wha qv m:k7pw(ax(t is happening to its acceleration, how does it change if air frictioxwpm(:va q k7(n is ignored?

  As a freely falling ob9d;t pfzu ,8fwject speeds up, what is happening to its acceleration, how does it change if air friction CAN NOT be ignoredz fwtf,;pdu89 ?

  An object that is thrown vertically upward will return to its oqogr i+5: q;yrrwg -r*riginal position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be altery* -:g ;wqqg+irorr 5red?

  An object can have zero velocity and nonzero acceleration a/amj.3 nqrbz 8t the same time.

  An object can have nonzero velocity and zero acceleration at the r.)x:;bhpbj9*1a zfjlq t;c lsame time.

  An elevator moving from the second floor to t4:hmuvprhe0a m92rg / he fifth floor making no stops along the way has zero acc/2 uh p rhm4arge0mv:9eleration all the time.

  A rolling ball moves froz+ m 5a.1u 2+ 9jsd spk:ftlr yi1nye8x7kd+xlm $x_1=3.1 \mathrm{~cm}$ to $x_2=-6.0 \mathrm{~cm}$ during the time from $t_1=1.5 \mathrm{~s}$ 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 $t_1=-3.1 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=4.3 \mathrm{~s}$ is at $x_2=8.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quar99 pnh9secay3r * qok+ter-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 s6gt /2oz lvwx p(i-yg5traight line, moving 112 m away in 13.4 s. It then turns abruptly and gallops halfway tgpx/iol-z2gv 6y( w5back 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 from 7zeajk 4w r w)lj-/0k23f ozyw$12 \; m/s$ to $24 \; m/s$ 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 g +sx7bi8zqk:$19 \; m/s$ to rest in a distance of 71 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reaa yl3cglsk5 1/ch a speed of $26 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $3.0 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essential9b2dc (y)vt koly top speed aboudk9(t)2bv oyc t $10.3 \; m/s$ in the first 10.1 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 uniobflkg5/b9 (ja,wo 1 nformly from a speed of $19 \; m/s$ to rest in 4.32 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 b: ousl wr6l**-qk:u6v kh-n,m rqgq6a deceleratiouor :- qlql,*v:hu6m6b*snk6- rwqk gn of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goig/ 2nw5fk :cjz18jayqa ;ozhr,-2 wx vng $25 \; m/s$ 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).    $m$