Suppose that an object travels from one point in space to another. Maka, *:lsk gzm+lmyz2+ye a comparison between the displacement and the:s g* ll2 yzm,zma++yk distance traveled.

  When is the average velocity of an 1f3 ; lpa.fmdxobject equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "from zero to sixte -evx n (s/j*igd.by)y in 8 s". This is a descriptio- .xg *)vn yebijds/(en of

  An object moving in the +x b7gba /-w0:fim5arsv vc *5sb 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 3rsi:e2hp)g o9jjgbu*i s 8l6to slow down as it approaches agg*jei26pio bj 98slu:)s rh3 traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-mc4l/99o izazm 5un /ix direction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleriz9i /z9l 5uo/anm m4cation.

  Suppose that an object)d :nc-ayrp2l is moving with a constant velocity. Make a statement concerning its accelecdrya:) 2-nlpration.

  If the velocity of an object is zero, does it mean that the acceleev4tnmj+t k jcu z68 ce1ue//cjitn)*9g.-zr ration is zero? g+e) j/n/8 czjz6- ektctr. v9j1u4mneciut* Support your answer with an example.

  Can an object's velolxp /e+(l3(ogxkxi-h city change direction when its acceleration is constant? Support your answer with an g(-xo(x+le/i klhp 3xexample.

  Suppose that an object is moving with constant acceleration. yi oqtt r,.q .nurq. (wi5t94y y4z7jv Make a statement concerning its motiz4r.v4tqnyiyqt5y u(7q.,. rt iwo9j on with respect to time.

  Can an object have increasing speed while its acceleration is decreasingdckh)k32 b 38)hlr gcd? Support your ahbch d3d3 ))cgl8rkk2 nswer with an example.

  Suppose a can, after 9 /9eyt yhpnjjw 0-q0nan initial kick, moves up along a smooth hill of ice. Make a statement concerning its acceleration. n-tywjq /9jehn0 p09y

  Under what condition is average velocity et: 6mcth)r ,qoqual to the average of the object's initial andt 6hq: to,cr)m final velocity?

  Objects A and B both start at re,5v)3dldkz 0ukdn z 9) gc( okbqg)n/tst. They both accelerate at the same rate. However, object A acceleratbqukodv ggd5, z))zk/ 93d0c)n(lt n kes 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 rate.(t;m* wt 7ngcp However, object A accelerates for twice the time as obn7pg*mw ;(tctject 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 absence of friction, whk, , xebds3g15 wv lsjj(i6tt(ich of the j1kst, vj3i6t( d5bwlx,(esgfollowing is true concerning its motion?

  When an object is released .m+se+,+y o rgcm 1gbm)n/bn c)s5kgsfrom rest and falls in the absence of friction, which of the following is true concerning its motion? bgg.,g+coy1/e )m ms+ )+csnbrks5 mn

  Suppose a ball is thrown straight up. Make a statement aq -n2:cuzz8p6knyfz/ bout the velocity and the acceleration when the ball reaches the 6:zfk/- nzun2q8pz yc highest point.

  Suppose a ball is thrown straight up. What is its 2 kgx )m w9oee-dx37qazc5m1f acceleration just before it reachexfeoga de95mx7 )z cwmq-1k23s its highest point?

  Suppose a ball is thrown strai0r9ms j:1z bncght up, reaches a maximum height, then falls to its initial height. Make a statement about the direction o0 1zrm:9cbsnjf the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum dahyzh:mk)x 3:g*od 1height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is com1:*zgk a hdxo) :mhy3ding down.

  Suppose a ball is thrown downward in the a sn63:+v/dcu6btze)wc v ym7qbsence of air resistance. Make a statement concerning iq)szu3c76tvnvy+d w: c6m e /bts acceleration.

  Suppose a skydiver jumps from a high-flying plane. : 5)z+s i:jijt jseue9What is her acceleration when she she reaches terminal velocity:je)uzs +iij9 :5ste j?

  A ball is thrown vertically upward with a sp4)bbiis ht8q0 l0wc/jeed 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 times higher does itcqb w h8/0si0l )b4jthe second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, ba y ex7siod96xvz*z33all B is dropped from the same building. As time progresses, the dis9x3o 3zv7dsy6*a ez ixtance between them

  Ball A is dropped from the top of a building. One second later, ball B icta dh9(9 tnn(-. ahv : )pmeulge.;bts dropped from the same building. As time pro9;-d)cn p(mvl:ag .t t tnue.h habe9(gresses, the difference in their speeds

  Two objects are thrown from the top of a taflyfj :p- ub*)zbsszm):bc2 6 ll building. One is thrown up, and the other is thrown down, both with the same iniy)sub zb *cz6) -pbl2s ff:jm:tial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A sec zbqtg7.3pm 8dond brick is thrown straight down from the b8m7 zd3gq.tp same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with cooru,d(3 l9 erpnstant non-zero velocity in the +x axis. The position versus time graph of this objec, 9o r(drep3ult is

  An object is moving with constant non-zero acceym:l;,w ej.d jleration in the +x axis. The position versus t:el.,ywjdj m;ime graph of this object is

  An object is moving with constant non-zer q0n33j1tb gal,:s vgbo velocity in the +x axis. The velocity versus time graph of this object isn b3b: lgaj1sg3qt0v,

  An object is moving with constant non-zero acceleration vo kpi *y1t;k*o4vf+:onzg1n in the +x axis. The velocity versuki1*on pt k;+zgono1v :4yfv*s time graph of this object is

  The slope of a position versus t5thjxr 1ia0o )mbn.: zime graph gives

  The slope of a velocimg,t blu/ 28,xpt/mv vty versus time graph gives

  The area under a curve in wpvihx s)ktb4s- q7+2 an acceleration versus time graph gives

  The area under a curve in a velocity versus time grac59 ( ay06oi),khybh7xea ivy 7ef lz4 (htm5kph gives

  If the position versus tipgpq+r4 )6hdm me graph of an object is a horizontal line, the object ispgmd4p + )rhq6

  If the position versus time graph of an object is a vertical line, t (uyj/zf0o /9dr t9yyehe object ise 9ort/0fyy/(yj9ud z

  If the velocity versus tim* 3jydwpwcy58hh 7 g5oe graph of an object is a horizontal line, the object ic 3 hydwy*gp57 85hjwos

  If the velocity versus time graph of an object is a straight -y/dt8+b /cvmodgonz7w : eo+ line making an angle of 30 degrees wi7+ygm v:o8c tdd/ewo +on-/b zth the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. * xex7*r eca/teu5vq2u c7vl7 Find both the distance traveled and the qleuvv*5r ux2 e/ cct7e77*xamagnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it take to move nbxx33t vx 2j+12 km upstream in a river flo vbxt3j23nx+x wing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609 mr mej(xl)(e r0)

  What must be your average speed in order to travel 350 v- u3tr(aa2u:fu fjg*g-0ak(0 iue zf km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) ig0ys1 z;06pj wv)stl fn 2 hours and 57 min. What is the average speed of the runn6tgs0p 1w sz;0lvyj) fer in m/s?

  A car travels 90 km/f7hmb b3)xoj4wd u9xe3d sk+s 6 1qhu:h. How long does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels i8y/ ;j cktw h,fxfq:w(n one year. The speed of lig q,tc /hfkw: wfx;(y8jht 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 sid ysr9bwf5 /2; bq jjl4o9g,txye for 4.0 s, how far do you travel during this inattentive perqftr 2x s,o;yjy9gb5j/49l wb iod?

  If you run a complete loop around an outdoor track (400 m), in 100 s, your averaw.- s+d: t .pnryxxrc,ge velod.s,:wr x +xpc-tr.n ycity is

  A polar bear starts at the North Pole. It travels 1.0 km soutsqs7 3sni.8a zh, then 1.0 km east, then 1siz nq78s3. sa.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 Pole. It travels 1.0 km south, then 1.0+2fmj jtdo/w)tg xe j/ 7fc1sx;s)pj * km east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. emg pd/ swj1+cjos7f)f*;) /tjx2jtx What was the bear's average velocity?

  You are driving home mgxm m+. +*pfnon a weekend from school at 55 mi/h for 110 miles. It then starts to snow and yo+ *xm g+nmp.mfu slow to 35 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 isqal 9;,ag26 thug7 vuc the average speed of the motorist for this trc;ua 2vgl7u q,g9ha6tip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km rld yal (jeg73ice04;/h. What is her average(ll;4 e 3j 0rgeiaydc7 speed for the trip?

  An airplane travels at 300 m31ystq0 c)gj ti/h south for 2.00 h and then at 250 mi/h north for 750 miy3)g0qjct1t s les. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the l0fz)g* mi ,4)u,pz*yrvmt s+vvsa x0cast 100 m) for team A can run 100) v,0xmu+)i*ssazty 4r z0*pvcf,vmg 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 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 10 s. 7 pvul*3e 8xjqwom n1-7b2ots;k k j9gThe car's average velocity during deceleration was 37 km/h. What was the carqujnbwkesmj7oovl7gx* k8p t 9213 -;'s deceleration while slowing down?

  An airplane increases its speed from 100yf2 dkou54fb)h 7)c y6hq ycd8 m/s to 160 m/s, at the average rate of qu)yhyf2oc)d7h b 568 kcy fd4$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h y,8h(x u hb.yuaccelerates 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 resw0tg;9 e4 jjdft and 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 sa9(renzz re5-. It then speeds up with a constant acceleration ofe9r- n5a( zzre $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 4.6 m/s experiences a cowfbva+4q,nrbv;02 t q(4d x cb k1zwn+nstant acceleration ob+d w w ab+,2(v n0bkvqtnrfcx;41q4zf $4.1 \; m/s^2$. What is the cart's displacement during the first 4.2 s of its motion?

  A bullet moving horizontally to the ru e:7r mwu-v(ek n*ec5ight (+x direction) with a speed of 329 m/s stri-ew7 vm:crn(kue*u5e kes a sandbag and penetrates a distance of 99.17 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an ai4cm.4)b e obmli h 0gq4p)e7zkrcraft carrier. It reaches a speed of 42 m/s at the end .44 lp ebic hm)gkz m4o7beq)0of 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 ig1 9w-6 gjvzxh2a0i6qtab j3with 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 20y)teq4gy zqe (9mot 0,0 m. What is its average acceleraty)(og4e z,0tqemq y9 tion?

  An object starts from rest and undergoes uniform acceleration. During the firsof ;;tna k:fm7t second it t foakmn7;f ;t:ravels 2.6 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initially w8.2z5d uzbxqit is travelq 5x2u.z8zbwding 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 unmzu3 d/;3 d,ct pwz+ii qh(v)3jcc-ryiformly 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 degfgs l o+.5tl yz7/k;ayd(e c0celerate 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 wa7zk)q/rtv(az bc( +rs iting at the inr)s /(r+(bazqzv k7t ctersection 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 plad;ivne /s k;*nnet X where the accelerav;kn ins;e*/ dtion due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward wit5d +g iazz4f-up+jh.k:-q jprh a speed of 12 m/s on the surface of planet X where -z.kfj:p+jpd ru5 i4q+hg-az 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/s on the surface of planetcz) 658 * j i2 v2gwvmae6sola73hjg:l r2kuie X where the acceleration d)e2r3soa2* uw za6ih5il8g cjg :v j7v2k6em lue 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 ax4ew9dmkfmf vg gcvj(352 /5z speed of 14 m/s on the surface of planet X where the acceleration due to gravity isk5fmfdegw 39xg254j vvmz/(c $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually greater than 0.10 s. Ifi o ri3jt) mbe8lj/zk7(3)wsw your friend holds a ruler between your fjz83ltwiw)i(be/3 r )sko 7jmingers and releases it without 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 bo i4y* 83h ciz74forwis its velocity after 3.w*47b3r4ociz ify8h o00 s?

  A bullet shot straight up returns to its starting point in 8 (vk0e st:jui,s. What is the initial speed (t i,vjeu:s k0of the bullet?

  A ball is thrown straight up with x8msv(p dt.:lee;9 uc a speed of 36.0 m/s. How long does it take to return to its startin.(eesd ;8 mplut cv:x9g point?

  A ball is thrown downward from the top of a building with ut3r 9bw sunvs-b6).hu8lhv* an initial speed of 18 m/s. It strikeshs) b w6 hl.ru-3u8vn9tsub* v the ground after 4.2 s. How high is the building?

  A ball is thrown straight up with a speem9fo( a28 fgrgd of 30 m/s. (only fill in numerical value in the bfg af28g o(m9rlanks)
(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 wi:t1*: b un b(ty/syq jqgmg(4 ibcct*:th a speed of 31.1 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 15 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 15.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1.0 gx l4; 0;)s3cu 0hgzg(sfozdn s?

  In Fig. below, what is the pb jcy+6,cg9ecfna5 vh- p7-b velocity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0 s10 xs.m5juktq;9xl iy?

  In Fig. below, what is the velp (f z.dsw.f 3oif*j3yocity at t = 5.5 s?

  In Fig. below, what is the average velocitx+ d9xoeh./ kq s/( nvvge8kh3gorpg ; +c6e+ey from 0 to 4.0 s?

  In Fig. below, what is the ave;1zql(tn*up-dqj xs 6l./ shf rage velocity from 0 to 6.0 s?

  In Fig. below, what is egpm2 c q9hyaiu6,/9w1(i1 ndrqoo +hthe acceleration at 1.0 s?

  In Fig. below, what is the acceleratioq 5z og.y6ue6bn at 3.0 s?

  In Fig. below, what is the average acceleratiok d*raow+9mv 0d8,n vtcvs 4,l3qqfk 3n from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 todb .svtn47 z f4o me.di4d2t)4xux9no 8.0 s?

  In Fig. below, what is the displacement from7;amyzo7; 5e v/hvixg 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {spee4kmmv g1lvg(q;s1ks k1(ih s 8d|velocity}

  An object can have a varying speed ifuzkji89y5gcw ucf:s*3 8 nzpl-hd4 :i its velocity is constant.

  The velocity of an object can be negative when its acceleration is positn lirw6pxz 8(4.sea l,fwd) 0hive.

  If one object has a greater speed than a second object, thr6n uhe* in;(de first must have a greater acceldirh* n6e (nu;eration.

  Two cars emerge side by /lq d 8z/osy-xpge o-2side 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 acceler. ++ i6yvowco *zjw4l8emtw4ration decreases.

  A baseball player hits a foul ball mt:z4:nh:6x j r3qkr qb0vn-xc wk5,fstraight up into the air. It leaves the bat with a speed fnzh :x 0vrkj 3w:, ckrtx4qqn6:mb5- 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 t9p g*eykg:yq r)(,fzuo its acceleration, how does it change if air friction ise:ry(zy*gq ,fp ku9) g ignored?

  As a freely falling obvx x1e)b1hp)znp(ff7 5 - npqiject speeds up, what is happening to its acceleration, how does it change iphiv(ffn7xzq n)- 1bp1x5p)e f air friction CAN NOT be ignored?

  An object that is thrown vertically upward will retl6i3,+nywh 3qqjc ch1urn to its original position with the same speed as it had initially if air resistance is negligible36c wy qj+li1hhq3 ,nc. If air resistance is appreciable, how will this result be altered?

  An object can have zero velin e(n *h;0tuwocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero +5w/mt z grj7djakt39k/w)m dacceleration at the same time.

  An elevator moving from the second floor to24: l,urz-e lg.rxq bs the fifth floor making no stops along the way has zero ac,2gsulbr:-lz.e4 qrxceleration all the time.

  A rolling ball moves si kdvk3nr7p *w3: n+ffrom $x_1=3.0 \mathrm{~cm}$ to $x_2=-6.5 \mathrm{~cm}$ during the time from $t_1=2.9 \mathrm{~s}$ to $t_2=5.1 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.4 \mathrm{~s}$ is at $x_1=3.3 \mathrm{~cm}$ and at $t_2=3.6 \mathrm{~s}$ is at $x_2=8.0 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight ce ob6dwk9wpm;g4fz1 3omplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 10.6 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,tcaty6pxwzvi57 - ; p- moving 105 m away in 12.pwc ;7-6 tzy-x vipa5t3 s. It then turns abruptly and gallops 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 ) pb7dz.7utva2sw fju( x+g4 f$11 \; m/s$ to $23 \; m/s$ in 5.8 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 frome qbf0y mzw51b9z5*im $17 \; m/s$ to rest in a distance of 74 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach uwr-zjqc w b38l0p*g ,a speed of $32 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.0 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speedi6 4b)+ vza lnj,5srtj about s ia+n4b6vzl,rtj)j5 $10.4 \; m/s$ in the first 10.3 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 uniformly from dv y4j(fkvg/t/+8yg8blxki2 a speed of $19 \; m/s$ to rest in 5.16 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks.-.d 4qpj eq q2o8xnjd 92 m long on the highway. Assuming aqd4xj. ejq -ndp28.oq deceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck going hh+cugjlc3;k1+dn61j /u4jonn ksu7 $25 \; m/s$ 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. After exkwdwnr3czhsn*i t;+ t 0)x o8+actly 27.0 min, there are still 1100 m to go. The runner must then acc);8t0io+tx w rh ncwnk s*zd3+elerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$