Suppose that an object travels from onvt*3vlqvp 9q (e point in space to another. Make a comparison between the displacement and vq pq(*93lt vvthe distance traveled.

  When is the average velocity of an obj ron5sk*pt3u*e + 6gvdect equal to the instantaneous velocity?

  A new car manufacturer advert 6emf1ypmix4 e(n,d-gises that their car can go "from zero to sixty in 8 s". Thise4(nmdg6x,e-pm1yi f is a description of

  An object moving in the +x axi(s+h 3jaqi.u ns experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) beuhmopcez4 mgk,eiu9rico -9(1a4u*yic 5 1 d8gins to slow down as it approaches a traffic-cgy8 4o me5c iz9ou dc pma*4ei1huir9k(1 ,u light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow down as gd -o9f7grlydb07 k;qit approaches a traffic light. Make a statement concerning itqfgkly0 d97rd7 ;bgo -s acceleration.

  Suppose that an object is moving with a consta -tdt)ok+6qx pnt velocity. Make a statement concerning its acceleratipkqdt +o-t6 )xon.

  If the velocity of an object i)c)ve)arqm i( s zero, does it mean that the acceleration is zero? Support)q)) c(ivmar e your answer with an example.

  Can an object's velocity change direction when its accelerat37dqif:dn c1bb;r9oe aqp2 i /ion is constant? Support your answer with an exampleqd7;9qi ecdnri:po b12b/af 3 .

  Suppose that an object is moving with constant acceleratp(lz*g0h73qm dl7 xm uion. Make a statement concerning its motion with respe*gx0l l7p z7mh u3(mqdct to time.

  Can an object have increasing spe m/rtq9d y /s1;6ernwxod(b/ze)7vp ged while its acceleration is decreasing? Support your answer with an e9n dmb/ v)tw6rsgyx/rpd;z1/q ( 7oeexample.

  Suppose a can, after an inirt7k1fvs eo:7u):iy ttial kick, moves up along a smooth hill of ice. Make a statement i oskuftev:t) :r 77y1concerning its acceleration.

  Under what condition is aver 6;g nclea8ja-age velocity equal to the average of the object's initial and fe aja-c;l8n6 ginal velocity?

  Objects A and B both start at rest. They both accelerate n/r, olocg nq7) ;h5vyat the same rate. However, object A accelerates for ty ;7oh cnr5oqv )nl,g/wice the time as object B. What is the final speed of object A compared to that of object B?

  Objects A and B both starjua b.1x b.jmohc :1h,t from rest. They both accelerate at the same rate. However, object A accelerates for twixhj1.,a1b:ojhmc b.uce 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 in the absence of friction, 3mdk84 yal5ggwhich of the am4 3 l8kd5ggyfollowing is true concerning its motion?

  When an object is releasensm8xw kau dsn 7to5e+:7qpw/lh:s2 7d from rest and falls in the absence of friction, which of the following is true concerso/77w uwm5 2dlxpt8 eqns: 7: +nshkaning its motion?

  Suppose a ball is thrown straight up. Make a statement about the velo. xq2 9*4.8ca hajllkvair9sucity and the accelerax ica a qrksl.j9v9au*28hl. 4tion when the ball reaches the highest point.

  Suppose a ball is thrown strai,sj+n kb: j2 edxlw)d(ght up. What is its acceleration just before it reaches its highest poinjl :w e2dx(+)dbjs,nkt?

  Suppose a ball is thrown straight up, reaches a maximum height, then falls to kgwqpj 9/leyz/(r;a- its initial heightka9zpqg(wyjel -;r/ /. Make a statement about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum heigpb7 sb;sn0*f fht, then falls to its initial height. s;7sbbfn *0 fp Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make kqj g.0:iu3tgz t2+-7dz fjpn a statement concerning itsdt:jgzkqig +7zp u-f2t.j3 0 n acceleration.

  Suppose a skydiver jumps from a u 4xylbwlo)7nb3g-g 6high-flying plane. What is her acceleration when u4 l-bo7b)3n6 wyxgl gshe she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identical o9;zl gcplk 5 1;xxkh:second ball is thrown upward with a speed 2v (twice axxlz;g:95p1c lk;ho k s 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, ball B is d z 44s5 /t (hg9rxqgx.c q,amd4diu)xaropped from the r4x x/t d4, 9).duqahqgs(gizxma4c 5same building. As time progresses, the distance between them

  Ball A is dropped from the top 9w rz5 vo3 *5vx*+jwopwh,i bxof a building. One second later, ball B is dropped from the same building. As time progresses, w*5+5wj vp3 xzob* v rx9w,ihothe difference in their speeds

  Two objects are thrown from the tox*sy-)*pk ( m ridomk-p of a tall building. One is thrown up, and the other is thrown down, both with the same ipr* -o*k(dkxmm-s y)initial speed. What are their speeds when they hit the street?

  A brick is dropped fr c7ual; 1 .vxpa8;f 9myk-jxhrom the top of a building. A second brick is thrown straight down from the s;9ju 7 vmyalkc hf1xrx-8;a.pame building. 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 velocity in the +x axis. The 8tj6hp+mk:ur position versus time graph of this object i:h8u rjmpt 6k+s

  An object is moving with con 6e( xy4j-**euuv3tk celycc(stant non-zero acceleration in the +x axis. The position versus time graeeyt*e(3c u*c(k ylx6j4- v ucph of this object is

  An object is moving with constant non-zero velocity in twi 7c r gb:daz5(p ,,n,pl3dcljo9l/ohe +x axis. The velocity versus time graph of ro dp3/7llo9cb,(ig d,czna 5 l:j p,wthis object is

  An object is moving with constant non-zero acceleration in the +x axis.qxbh-va,tj)e8u; :y p The velocity versus time graph o8tue x)a bv:qhy,;p-jf this object is

  The slope of a position ve90 g:ddn+ xnanx7;juyxqi98 s rsus time graph gives

  The slope of a velocit9uhzu8 l ldy/8y versus time graph gives

  The area under a curve in an acceleration versus time graph yhp kyrdtx i(.,ff1/h(a9joyw)oq8:gives

  The area under a curve in a vel./ tb6,v rxsbcu0g8eg ocity versus time graph gives

  If the position versus time graph of 6 fdpj*y-;pxq an object is a horizontal line, the object is fjx;p *dp6y-q

  If the position versus time graph of an object is a vertical jj uey 60a(gu4nu6+uv *h 1kxtline, the object isj 1*nkgy+ueutax v u0u(6 4hj6

  If the velocity versus time graph of an object is a horizontal line, the u53s i*,wqd/b6hw;/v8 vrfi6klw uzu object isw uikwvd,vq;3* u bzhl8/wi665u fs r/

  If the velocity versus time .f z)fi6 wiy2bgraph of an object is a straight line making an angle f6w y b2.i)fziof 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 distancfb 3 21c 4dohc g*um0rj d,y9tn+18ew 8pcsqvne traveled d c1+m9epc qnh80gctrf 1nv4 s8 *2d juy3bw,oand the magnitude of the displacement vector.

  A boat can move at 30 km/h in still watw t p0btk- r:t8 f4dxer2)ma7oer. How long will it take to move 12 km upstream in a river flowing 6.0 km w8t)beot xd0 kf:rtr7m4 -2pa/h?

  55 mi/h is how many md u5vda 2,cy3n/s? (1 mi = 1609 m)

  What must be your avehblk-. -h.dff rage speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours andkl i;;0 1l5 tp(mrmyzd 57 min. What is the average speed of the runner in m/s?mmk;ll;5y(zdi 10p rt

  A car travels 90 km/h. How long does it take for it to trc6h qi yn)i:(ravel 400 km?

  A ly (light year) is the distance that light travels in one yearm :lu1*ln du0lco;t7b . The speed of light is ;u 7u:l0c* bdmotl 1ln$3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 72 km/ha69/zg7up e kn along a straight road and you look to the side for 4.0 s, how far do you travel during this i/ag z9nkp76u enattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 szng,0/x33 a6flsxno l, your average velocity isx3 nl la/z,0 gf3nsx6o

  A polar bear starts at the/(sjy1 uypuz0c5(b 6chsa9 ro North Pole. 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 a65as1z(rcy/su(hj u c9 po0 ybverage speed?

  A polar bear starts at the North Pole. It travels 1.0 km(y)q niu d0oe( 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 aviu0en (y d(o)qerage velocity?

  You are driving home on a weekend from schooqo ogca-x46cv -q n74zl at 55 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 qcqag o-x v4cz-o4n 7615 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and -zwjg n0p:i/m 160 km at 100 km/h. What is the average speed of the motor-wzmipnj g /:0ist 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 y xmej,* /yb-rq;s z,zo*j /czaverage speed for the trix/zyj zs/*,bry, jmocz*;-e qp?

  An airplane travels at 300 mi/h south for 2.00 h w*l;gt8h,i. yt:gp tkand then at 250 mi/h north for 750 miles. What is the average speed for the g.wt;l8it g p:t,y*kh trip?

  In a 400-m relay race the anchorman (the per g(srh6+8 c2/dzgapttson 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 starts the final leg of the race, in order that the team A runner not(sc+8 zgg 6pt d2t/ahr lose the race?

  A car decelerates uniformly and comes to a stop after 9 s. Th ui1ly 27nbcfe5 2t-6lb3gf:*f5 uf o:vnffb be car's average velocity during deceleration was 38 km/h. What was the car's deceleration*i ::ltu7u o2v3f fc-nby6bfnbfe1fl fgb5 52 while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average rate op +i rd,k82agjf , dg8j2+karip $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates n0y5j+3u- xfkugv0-zjyxa df * 8r we9at 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 accelerat lcwk 0/k;y lcly56*ihes 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 with a constant accelerat-.3bm zrk n4ujion o-43.nz rb kmjuf $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 5.2 m/s exphqgd kgp/t- -+ef19rej , xc;ueriences a constant acceleration ofq ceh tpdef ,1;u-+r-/kg9jxg $1.4 \; m/s^2$. What is the cart's displacement during the first 7.1 s of its motion?

  A bullet moving horizontally to thech;et0.:pc/pv 9gx ug20 yopl 9e1iwk right (+x direction) with a speed of 356 m/s strikes a sandbag and penetrates a distance of 25.13 cm. What is the avera.kypg t9uip 00c ;:o vph1lege2 w9xc/ge acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a ca:d yvj;m)ag:* yma4c jtapult on an aircraft carrier. It reaches a speed of 42 m/s at the ):ymaj *dc:gmvy;4aj end 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 mos-buq /jr igt+aqwvag+; *y:.ves with 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.l1u h0 pp:6pfbo+bya - What is its average acceleratpbl1f pp:0a+oyub - h6ion?

  An object starts from ;+.qa0 ,b1euz zj; gz;opwk qprest and undergoes uniform acceleration. During the first second itgu+ opqzq,;;j10 z zepk. ;abw travels 6.2 m. How far will it travel during the third second?

  An object is moving in a straight line wy/uof8 y2uc k7ith constant acceleration. Initially it is travel7 28uckyufo /ying 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 uniformly ata+ez bx771 ozk $3.0 \; m/s^2$. 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 at abo:pg-bf(4m j nfuxkx/ ,ut $5.0 \; m/s^2$ 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 traffic5 a odmpa*4dqinj+;e7:s8l 1k dx .col light turns green, a car that has been waiting at the intersection stp dnxq5*d718l .jm4k o:;dieaoa +lcs arts 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 mb 0xr-u9tsg2 j/s on the surface of planet X where the acceleration 9ju0sbg2 -tr xdue 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 pa(hej 2gz01gq0di/ kzlanet X where the acceleration due to gravity edq z0(a 2ghi1jg/kz0 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 plj*5 d2jl +us asglr;0nanet X where the acceleration due toss2gl0+a5u d*nr;jjl 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 mcjnnw-i7uk won642i r5 hzs 3 t;ry9(v/s on the surface of planet X where the acceleration due 6wizhsk;tuc - (nr2i43 jv y9o 5wnrn7to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usualq+j) ,w bpz8jcly greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, ho+cj) b8,w qjpzw far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocitbhgo2js5 5w hq/:+sbpy of 19.6 m/s. What is its velocity after 3.hp5 wjssb+bqg h5o2:/ 00 s?

  A bullet shot straight up returns to itszjqq6nq ct9uq/x ff-43 )4 fjf starting point in 4 s. What is the initial spe/tjc49q fn q4q6f jzqffu-) 3xed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. Hgw6 erb)a1d +co4ox 8aow long does it take to rd+ )x4 g6b1oace8woareturn to its starting point?

  A ball is thrown downs9 3a8xs:qtx dttr/ow0l 5k,zward from the top of a building with an initial speed of 6 m/s. It strikes t3rt/x5q:dzst0kl a x8wso t 9,he ground after 3.0 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fillj-.ak 8 dphg.hvro-i6 in numerical value in theg-rd jka6 h8.vp io.h- 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 a9,y.f xju7si v speed of 23.5 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 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 x kczc-h(3g)hs?

  In Fig. below, what hpt2s) y1 fmkh/gvhuh;8s0a.is the velocity at t = 2.5 s?

  In Fig. below, what is the velocity 6o4o dsm:c3 iwat t = 4.0 s?

  In Fig. below, what is the ve+leabg4/ : uqqo )-hvdlocity at t = 5.5 s?

  In Fig. below, what is the average velo. sam* h1-q4)ssazn licity from 0 to 4.0 s?

  In Fig. below, what is the average ve:1d kqbdw hni8 5f-3qblocity from 0 to 6.0 s?

  In Fig. below, what is the accelerati l/*m(mp*w nj3 ybx;wron at 1.0 s?

  In Fig. below, what is the accelery*h( lla )sf3mation at 3.0 s?

  In Fig. below, what is the average acceleratio :hxn2v7t pdp58rd4n qn from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.0 nrrysyt)kf5(6wdy) l; e)eyl1;a2xcs?

  In Fig. below, what ig as*)apc-n7z1uxr. ms the displacement from 0 to 8.0 s?

Does a car speedometb3e s)e6h+ fwgl hy3/x fz47hoer measure speed, velocity? {speed|velocity}

  An object can have a varyip (3e6qv4d 4kb m vnt+lezpzk/4vx- y)ng speed if its velocity is constant.

  The velocity of an object can be negati exgy(m/jq7-tzf bw2/:j s :fwve when its acceleration is positive.

  If one object has a greater speed tq1m+pxyz 2s3khan a second object, the first must have a greazy2x s+kqm1p3 ter acceleration.

  Two cars emerge side by si; +w15aiyiz l5jw)gnvde 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 v( sfrjg ;z4.io6bwbi,(zo ( vspeed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It ls l g0xf fn4u)j6cyr3-eaves the bat with a speed ofc4fgr3lnj6 xy 0- suf) $120 \; km/h$. 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 its5 uu qljda*;gb; )w,re acceleration, how does it change *euu,5; wdg qab rj;)lif air friction is ignored?

  As a freely falling object speeds up, what is hapnt-b( rzcw+)lhq /rmk-j/1fk pening to its acceleration, how does it change if air friction CAN Njrnkt lz/q1 -)h(c/+ bkr mfw-OT be ignored?

  An object that is thrown vertically upward will retur+o): bk mmm2wr3qvsf4n to its original position with the same speed as it h+vqm 2 k mmsrf4)w3ob:ad initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration at the g v5 gi2+5c9cw/wmzvh same time.

  An object can have nonzero veloci)r3c+k v ,j7frf0ob-e5smtdmjx0;-q ) k urskty and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor making no stpqh 24n/wc;vx ops along wq/hv;pcxn4 2the way has zero acceleration all the time.

  A rolling ball moves fr 14jetqg ,6eaviti 2typok5,7om $x_1=3.0 \mathrm{~cm}$ to $x_2=-4.7 \mathrm{~cm}$ during the time from $t_1=1.1 \mathrm{~s}$ to $t_2=5.7 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.7 \mathrm{~s}$ is at $x_1=2.7 \mathrm{~cm}$ and at $t_2=3.7 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a jn; ;9ux;q3u6y7o kqehr ze3oquarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 9.3 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 91 m ax*hqqo;5 7fb+, w9+( etp/o krxwfx5u;oie rk way in 12.8 s. It *q7bq9+xpee(5 wuhoxk/r x5ko;, of i+;frt wthen turns abruptly and gallops halfway back in 4.6 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 frob6pzom/5yxp3c ,5xpxm1u /iy m $10 \; m/s$ to $25 \; m/s$ 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 from sfhr 6mz ok3ffy2;u5bsgru7w:5k6w ,$19 \; m/s$ to rest in a distance of 68 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a spee1aejy, m58xtw*eep4/f hi *ib d of $33 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.3 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speed abouex /y0an)iid ;tidae0i/;x)n y $10.0 \; m/s$ in the first 13.2 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 unif9godb r+6d 9 -0gl3hl;zuwwxs ormly from a speed of $18 \; m/s$ to rest in 4.54 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car i1f k/y5i5 amfak4/gnleaves skid marks 92 m long on the highway. Assuming a deceleration of 1f4 i a55a g/ikkfm/yn$7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a tr7ikf6x kuq .xktm+szo/6 f1x1 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).    $m$

  A runner hopes to complete the 10,000-m run in j v7x(t a:8 hy-; nfhqfxlcs98less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runnert(;fvcs hjnq:9hla78 xfxy8 - must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$