Suppose that an object travels from one point in space to a;j 0 irdt kuh1* aft5uq9y6z+vnother. Make a comparison between the displacemenh5 9z0q+6 itkuaj;yu1rdtf*vt and the distance traveled.

  When is the average ekj n1o3l4 5 hv:-hsu4bxsj5r velocity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "from zero to sixty in 8, x-kzpe(dfh,na8n::mo( i kt s". Thisn imt- ((f, dah,o ::ezxkknp8 is a description of

  An object moving in the +x axis experiences an acceleration of vbn1jrq 1(( f ik57jiu$2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow *a )c k*d zx(+ceom4drdown as it approaches a traffic light. Make a statement codd4o(c)m *zcare *x+ kncerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to sl u25m dqv8ih6low down as it approaches a trafh 6 lqd2uv85imfic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make1cxxn)nz4dhfr d 7y3fbnz79 * a statement concerning its accelera)hbn fxdz1x7 dnz 3nc7 r94*yftion.

  If the velocity of an object is zewl)z;6,r bqkyn 5jz mjgd-5+nro, does it mean that the acceleration is zero? Support youkzj zy5q5d njlmg;r-+6bnw) ,r answer with an example.

  Can an object's velocity change directi(kihzr2 brl fw16l0/jon when its acceleration is constant? Support your ans6kjlzlrr02 f1/h ( bwiwer with an example.

  Suppose that an object is mov72 lpg 8misjk0 t*ik4ying with constant acceleration. Make a statement concerning its motion with respect 0 p k2* jgtlk8iy74misto time.

  Can an object have increasing speed while its acceleration is decreasing? Suppaqu*p 2 h r,umi((eacdink*.t ,;r0mvort you,(* du2rip0k (*, rac eviqm;nt m.ahur answer with an example.

  Suppose a can, after an initial kick, moves uf9akol5a p* g/p along a smooth hill of ice. Make a statement concerni pfkaa 9l/g5o*ng its acceleration.

  Under what condition is average velocity equalxc2c8(4ky k :b:fope k to the average of the object's initial and 42 :c:ybk efk(pc8xkofinal velocity?

  Objects A and B both start a) nxfsty 4bl1wt49vk 0t rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final speed of obbtxf y0t w9slvk41)4nject A compared to that of object B?

  Objects A and B both start from rest. They both2r j56:mv gbsr accelerate at the same rate. However, object A acceleratesrvjs2g5 b: 6mr for twice 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 ibjswj8qx 0,g 4n the absence of friction, which of the following is ,w4j0s8bg xqjtrue concerning its motion?

  When an object is released from rest an( p8sz,po xp6rk49bi bd falls in the absence of friction, which of the following is true concerning pskb(oz4,p98 ri bx6p its motion?

  Suppose a ball is thrown straight up. Make a statement about the velocity a *em 2e)rwoq-bnd the acceleration when the ball reaches the high-2 rew*b qm)oeest point.

  Suppose a ball is thrown straight up. What is its acceleration juozaazd++,*)(mngtmb+a .o 8 qj8 cko qst before it reaches its highest n8*(zdacta8km+zg o .aq q+mjbo, )o+point?

  Suppose a ball is thrown straight up, reaches a maximum heiq;;; pybd2yzp 6mbn-rght, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball drb;6m z;y2qby np;-pis going up.

  A ball is thrown straight up, reaches nru2q88lvj j 2)gf)p/7uggbv a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and a2)/2)vjv8j qu78 p gl burngfgcceleration as the ball is coming down.

  Suppose a ball is thrownkpg;-(67y ech;bgh xw downward in the absence of air resistance. Make a statement concernin -hgw ;7xk;p(hge6c ybg its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her accelerati5uw eny o 12bar,;cn,gon when she she recg2;1wo,r 5a y enu,bnaches terminal velocity?

  A ball is thrown vertically upward with sf(x74/vh c joa 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 times higher does the second ball go than the f ( ho/jfcsx47virst ball?)

  Ball A is dropped from the top of a buildk2j f.zm,7 ncofg0m1oing. One second later, ball B is dropped from the same building. As time progresomnk 2gc.zf17o f 0jm,ses, the distance between them

  Ball A is dropped from the top of a building. One second later, 0*8w x 3m syhpp05q vr.syjk)mball B is dropped from the ss 0sm w mjpv83.*py0hq xyr)k5ame building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall be7k pz+1 el:v.tr( fyquilding. One is thrown up, and the oth1fle rvy:7z(eptkq+ .er is thrown down, 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 second brick is thro5 o,u.fk v3-d6mzjnvdwn straight down from the same b jvd5nzdkou6. mv-f,3uilding. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero veq(gxloju2( qw/m y: s*locity in the +x axis. The position versus time wou (qm/ :*gs2jy(q lxgraph of this object is

  An object is moving withqtm67tl q f.kj.t2 wi: constant non-zero acceleration in the +x axis. The position versus time graph of th7.6: t 2 jtfqkmlqitw.is object is

  An object is moving wine/2ffr .3nzunrm rhabm1 ic.q2b 192th constant non-zero velocity in the +x axis. The velocity versus time graph of this obje/ n .mfnqc.2nr h ur2b9b123rezaim1f ct is

  An object is moving with constant 8mq2samtt;+c5 ld8q7c c yll,non-zero acceleration in the +x axis. The velocity versus time graph of this object mt 8da5c qcym+l2lq, c;ls8t 7is

  The slope of a positryi.1e1 e+ t)(w s h*c6uyfit*qkgmm -ion versus time graph gives

  The slope of a velocis yi-aumr3b+ 3ty versus time graph gives

  The area under a curve in an acceleration jskok064p c 9gr7 jqx*versus time graph gives

  The area under a curve in a ve0 iuf1.kvi*yks+oef mn65t- dlocity versus time graph gives

  If the position versus time graph of an object is a horizontal 4g.18 1l*o7nkr9 ayxyq qm stvline, the object vqs7*mo .yq 4l8x9ya1n1 kgrt is

  If the position versus time xq1 bb0 m(f/yjgraph of an object is a vertical line, the object isbfq(/j1bym 0x

  If the velocity versus time graph of an object is a hord 5se7y7we ybsa4e(l,8tg -wap-6d itizontal line, the object i7bta (wya-dpesw,ee-4t58 dl6 sy7 gis

  If the velocity versus time graph of an object is a straight line making an/djpk6y ;4*dhoi.uva angle ofid ya6d/;*jo. hvp4uk 30 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 tr*61s d5t rxhe rfsu(a5aveled and the magnitude of the displacementssd65u5 a( rhe1xr*t f vector.

  A boat can move at 30 km/h in still water. How lo)r/ uj 82s:.a)rzyial jgd3kvng will it take to move 12 km ups3u ra.r2g kjsyja)vd l)/i:8 ztream in a river flowing 6.0 km/h?

  55 mi/h is how many m/s dqoa2e3 f7w2v? (1 mi = 1609 m)

  What must be your average nwrl b.w6t 2b th433)hllq4ygspeed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (appro,2.xxe 1 .yiiwxnd;svximately 42.0 km) in 2 hours and 57 min. What is the average. xxed x;iy.wi1ns2 v, speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to travel 400 km? l330 t i(*jjfngsoop6

  A ly (light year) is the distance t/mp2bl:cyi :) wgn vd9hat light travels in one year. The speed of liv9yi 2dw:/)bmgcl p:nght 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 side f 7jfts4mac.o 3or 4.0 s, how far do you travel durm 4s7c3ofjat .ing this inattentive period?

  If you run a complete loop around an - 1 czwrs b81,ibgf0bql39fe doutdoor track (400 m), in 100 s, your average veloci c1wi qzrf1 8 b,df9lb0bs-eg3ty is

  A polar bear starts at the North Pole. It travels 1.0 km-b b ,:n,*kmd;tl zlot. 8ik)2bkdkpg south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its sb:ig-8k *dk;p2lnzbkbotd tl m),.,ktarting 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 kdp2s14tfofj.e.9 nv mym (,kqe8h x5pm 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 velocityjp 9.2xk emf8n p 1oh45msqvt (de.y,f?

  You are driving home on a weekend from school at 55 mi/h for 110 m8k nv2l rolfa(.stv70iles. It then starts to snow(2 7ltnvk0.v r flso8a and you 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 is wmkz:*jj*rmu,j9:9 t/if yk i*d ;lyuthe average speed of the moky :/9i*yz;jujm *k rm:t,i*jd fw9lu torist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h.2midlak wp.1 ( What is her aver.wkid(m 2alp1age speed for the trip?

  An airplane travels at 300 mi/h south for 2.j 1x z:(0wkt 7gkvu6hk00 h and then at 250 mi/h north for 750 miles. What is the average speed forjvx0:k zh u 67wgk(kt1 the trip?

  In a 400-m relay race the anchorman (the person whol(kj 1f:*jm,blqa+vn 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 starts 1jblnakl+ (vmqj,:f *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's avc/ te*t;loqu-(u8ej4vmx oj./yej j/ erage velocity during deceleration was 70 km/h. What was the car's deceleration jte/e j (cmu ;oly/j-o* txejv/u.4q8while slowing down?

  An airplane increases its bnj02a3d fu 3v6hiahphfw)g + rm.l3.speed from 100 m/s to 160 m/s, at the average rate of r20)naw6+ivhfpu m3a bhgj.fld3 3h.$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates azfmw17dev1p5k(5aqa k- 2 ep 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 accele5j- w 7/i;0ev. bgbu*ni p+1dust dckaf9ep:drates 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 s. It then speeds up wit-h4aho l mge,3m+p/ r,kn8gcw h a constant acceleration ofhm+ga,og8e mprc-3lnk4/w h , $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial vez 0)5w9oqj uxdlocity of 6.7 m/s experiences a constant acceleration ofwd 0)5oj9zqxu $2.7 \; m/s^2$. What is the cart's displacement during the first 9.2 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a spe;9ix q)u:ldaoqi h:t 9ed of 299 m/s strikes a sandbag and penetrates a distance of 25.13 cm. What ;99q:tuli)hi:odxq a is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on ar g)uf8+hwe (ln aircraft carrier. It reaches a speed of 42 m/s at the en+ rlfeg )whu(8d 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 constant acceleration mo3hp.a8bjd. 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 oe(s2y:n b3vq is its average ace v2b o(q3sny:celeration?

  An object starts from rest and undergoes uniform acceleration. Dursi : d:mo.uu4sing the first second it travd: u4:m.sos iuels 6.1 m. How far will it travel during the third second?

  An object is moving in a 0 1n8i tewk3asstraight line with constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveliwent3i a1s0k 8ng at 10 m/s. How far does it move during this time?

  A car starts from rest and 7f93v08dfffxnd a(qp3nokg nlhp y 69.- xw8yaccelerates 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 3( tue)n yezg-+ fng1ddecelerate 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 tz sf: d, z4qas(,d:t2fza)fif-fw8mwhat has been waiting at the intersection starts,f aia: zdzwt24,w:mffd8( qzs-fs)f 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 planet X wt5 fplc*/+odrd5h czf o/8jc7b 5d u9vhere the acceleration due to gravity is zu+ 5 rhc5dlocbfo9j78/5d/c*tpd fv$1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12 m/s on thexp:tob8-xwi 3 surface of planet X where the acceleration d-i xpbx3 o:t8wue 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 su( vg)iu5;aw qmrface of planet X where the acceleration due to q w(5;gvau)im 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 plane3,f(lhts ;mmq+q(j.3eqbt wbt X where the acceler wme ,.(q(tmbthl +js;bqfq 33ation 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 than 0.10 s. If your frqwww mwth0t 1 oxt89-4iend holds a ruler between your fingers and releases it without warning, how far can you expect the rulet9w wxw-moq 8wh1t4t0 r to fall before you catch it?

  A ball is thrown upward at a velocityth:i9g-hl,d)wb 3trm0.mw0t k1ja -c f(zurm of 19.6 m/s. What is its velocity after 3.00 m9t(-l u,0aw ). mwdttcrik z-0jhrhb3gfm1:s?

  A bullet shot straight up returns to its s3dwquhib ow7yk- ()8 ktarting point in 7 s. What is the initiqh)d ukiwb8o w3y 7(k-al speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long do2 f,mfclj;:vzr+ :gines it take to return to:;2zfjcgf m r:i +v,nl its starting point?

  A ball is thrown downward from the top of a building with an initial sp zbx9amq r.36u(x* gvq) h +rvh)au9daeed of 16 r q96h)rabh.)uvmzad q gxx ( u9a+3v*m/s. It strikes the ground after 1.4 s. How high is the building?

  A ball is thrown straight up with a speedm *ca2d w2+jfu*y24 rtl ;annu of 30 m/s. (only fill in numerical value in the blandw+2tncmj ;y2l4a**n f 2auurks)
(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 tszsp t8k0,arma2 0t7bhe air with a speed of 24.8 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 3 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 12 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 12.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t kwpy 5e+k;fu jmf/rl)vy3i yx06l3 zp0 p3f+a= 1.0 s?

  In Fig. below, what is the vrl 4tya:v;i)d elocity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0 s?tqm1*fm g- spr4k.q4m

  In Fig. below, what is the velocixmz7i d*2 mul(-/ j(0vzelt pety at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to 4.0qwo;/4pfjuq pn:dm+g3 h )d4y s?

  In Fig. below, what is the /zco*:av2or t;:omak ci.lr+aib s+1average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleratio/a9abwhsnm3 4n5 1xphn at 1.0 s?

  In Fig. below, what is the accelerati+db *thw-wbx0on at 3.0 s?

  In Fig. below, what is the average acceleration from 0 te sl.su bpr57.o 5.0 s?

  In Fig. below, what is the average acceleration from 0 ksb*kg;z)tnjmz- h:: to 8.0 s?

  In Fig. below, what is the sw3;d6x -xkfm displacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|vmt m+/7y sy;gdelocity}

  An object can have a varying speed if its velocity isu.c tf f fjkzmk76l39;t+c p2r constant.

  The velocity of an object can be negative when its ac o; hwb*(mhh.cceleration is positive.

  If one object has a greater speed than a second object, the first mustpi 3qow 49+;5dswel */xqplz t have a greater a+/ies9pl4 w tw* q;5xld3oqzpcceleration.

  Two cars emerge side by side from a tunnel. Car A is traveling with a speez+ hlvbz 9:tnpzkc96 9d 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 acceleration decreas;bwj dnufs4 .;2u 3xdtes.

  A baseball player hits a foul ball straight up into the air. It leav:vct (f/ e1yrwes the bat wve (c1f:twr /yith 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 4v+f*kz drknr6am3) g is happening to its acceleration, how does it change if air friction is ignored6r3k 4m*gzk+a vr)fdn ?

  As a freely falling object speeds up, what is happening to its acceleratiq qr+2xst6.jzok 1v9yf6 my(jon, how does it change if a6zsx+ qj21k 6y9(r. myvqftjo ir friction CAN NOT be ignored?

  An object that is thrown vertically upward will return to its originalda;,y f/- rvo;:olq kw position with the same speed as it had initially if air f/wa o;- d;rv:lqy,ok resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zers-1pd 7u cslw9o velocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration a5 qql-vcc*fi -t the same time.

  An elevator moving from the second floor to the fi+xo) fbh9c7zy6 pc w 7m,jnn)jfth floor making no stops along the way has zero acceleratijy9,+o7c xpmzn7 jwn )b6hf )con all the time.

  A rolling ball moves frh bn8e)/exg) gom $x_1=2.7 \mathrm{~cm}$ to $x_2=-8.2 \mathrm{~cm}$ during the time from $t_1=2.5 \mathrm{~s}$ 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 $t_1=-4.0 \mathrm{~s}$ is at $x_1=3.0 \mathrm{~cm}$ and at $t_2=3.3 \mathrm{~s}$ is at $x_2=8.4 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps-i hxf48ftf +g around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 8.4 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 lb(qjpo.,fw d*h0rt 7mine, moving 106 m away in 10.9 s. It then turns abruptly and gallops halfway back in 4.5 s. Camtojdhq(7 *0r .fpbw,lculate (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 frov6paux4 j n8:lm $12 \; m/s$ to $23 \; m/s$ in 5.9 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 fro/bky4 +j-.s cdaq v*hlm $21 \; m/s$ to rest in a distance of 84 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speedbfcvi*r.z/ b 0 of $29 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.4 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essent 8o:9etiq:xp d 9.jdz oo-qux6ially top speed about e:qq d joxd:o9ip.u6t9x-8zo$11.3 \; m/s$ in the first 13.6 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 uurn--.0gszs speed of $17 \; m/s$ to rest in 4.13 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 ta:gp *y(sh e5che highway. Assuming a decelerychgs:e( p 5a*ation of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck lcv6,u)dtjryt; tkp20.s o/n xg fj6/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).    $m$

  A runner hopes to cow/m;kpv 4)hj umplete the 10,000-m run in less than 30.0 min. After exactly 27.0 min, there are stilvk)j /;mh4 wupl 1100 m to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$