Suppose that an object travels from one point in space9,c lo(xc ntio9v :35v u2zfxn to another. Make a comparison bexv:9xzcvn ioot 3f2 , c(5l9nutween the displacement and the distance traveled.

  When is the average velocity of an object equf.w :7cfzwj,nal to the instantaneous velocity?

  A new car manufacturer advertises.u pd4*vs45:fsceiwmn9s 8 ug that their car can go "from zero to sixty in 8 s". This is a descriptionf.ncss9mg8*seu 4:d v45u piw of

  An object moving in the +x axis exts20+.gz h baj 3xnd*xperiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) b1ygvvmz ,glhir v.-2u- 8 etjo)nt50legins to slow down as it approaches a traffic light. Make a statement concerning i), lv81j.g h5vgvmun-e 0ztyior l -t2ts acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow xh9 )qaxe3t j/1k al0.am/oe/xz p7dd down as it approaches a traffic light. Make/ t /.7m xxajel0a qddx31ekzpo )9/ah a statement concerning its acceleration.

  Suppose that an object is moving with a constant vel7 kj9*egt fof8ocity. Make a statement concerning its ace7k89fjo f*tg celeration.

  If the velocity of an object is zero, does it mean that t3oz8pl 2wc ftmr++6s4h/zz ukhe acceleration is zero? Support your answfu8ctz463zz2sr l++okh m w /per with an example.

  Can an object's velocity change diruuk-w 3sol;oi 19 p5sdz -8ykrection when its acceleration is constant? Support your and8oopi-klyrku5 3 ss- 91 ;uzwswer with an example.

  Suppose that an object is moving with constant )mc4aw b 4i0am3drph d+cq5r7acceleration. Make a statement concerning its motio7h drma)wi 5c04q br3ca+ m4dpn with respect to time.

  Can an object have increasing speed whilexh63guk 1g bum4 i0mz8 its acceleration is decreasing? Support your uukgig8 4 x31m hzb6m0answer with an example.

  Suppose a can, after an initial kick, moves up along a smooth hill of ice. Makmjm th.gx.. v*e a statementjh *txv... mgm concerning its acceleration.

  Under what condition is average vm4m)qj d;hc,un0u n j/wp.h j0elocity equal to the average of the object's initial and final velocitjuqu;,j dc)n jh0h/w4mm0 pn.y?

  Objects A and B both start at rest. They both accelerate at the saoz -vrp8 2edz- vyg8f3me rate. However, object2d- pr8- ve8ozgyz 3fv 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. Thbwyhr(ah ,.;g4d*qfjey both accelerate at the same rate. However, object A accelerates for t(haf.bg,r*; dj qyw4h wice 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 z o+v1as4wdq d4 34wtdfriction, which of the fold4 qa zw+ovdd 3t144swlowing is true concerning its motion?

  When an object is released from rest and fia o1q8hzgpf;02 yn 6rbpr w9-alls in the absence of friction, which of the following is true concerning 9-hwr piqapfo82;gr6 nbz10 yits motion?

  Suppose a ball is thrown straigh)r1:ndmab a3:va /mwj t up. Make a statement about the velocity and the acceleration when the ball reacheswvn3:b ) a1aj: rammd/ the highest point.

  Suppose a ball is thrown straight up. What is its accelerati +jxnvaj.. 7t tkfj-c*on just before it r.kat *x+fvj7 jn .tcj-eaches its highest point?

  Suppose a ball is thrown straight u0z8mgnm ao28vp, reaches a maximum height, then falls to its initial height. Make a statement about them z20 vmg8noa8 direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, tjix3j(voy/ y+8w)rxb hen falls to its initial h yivyj (3)w+ o/xxr8jbeight. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown down,+xljikg:5)iku oyfo,( (re h ward in the absence of air resistance. Make a state+:lo,5r (kiu) ie jk,gyxho f(ment concerning its acceleration.

  Suppose a skydiver jumps from a eljjvdp +;u1mtf 3f c/1wv.t3 high-flying plane. What is her acceleration when she she reacheste . fcfv / ;+jw1t3v1upjd3ml terminal velocity?

  A ball is thrown vertically upward with a speed n:f89mcgdc-f v. An identical second ball is thrown upward with a speed 2v (twice as fa9n f8gfmd:c-c st). 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 .qs/7nm+ 6iwg orrd 6bkewy 02second later, ball B is dropped fromidwr g + s6wbr7/2o0mq .ken6y the same building. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One seco-jy x eh,v)at6nd later, ball B is dropped from the same building. As time progresses, the differenc,j6eyvxt ) ha-e in their speeds

  Two objects are thrown from the top of a tall buib)y;tx:xp/c qcfxnfz *5 t,.ilding. One is thrown up, and the otherixf* 5nx/cq:b;t,ptyf.zx) c 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 brid+)ex/fr+ ez:z0ea9gu 2g kdkck is thrown straight down from the same building. They are released at the same time. Neglect air resistance. C/zeu xa9r+ 20k )+gdg:zefedkompare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The po6:o0 fvr folt3namh29sition versus time graph of t30noo2 f6hlt afv9m:rhis object is

  An object is moving with constant non-zero acceleration in the +x axis. Thqhl 9ig 4,o 2bo2d(avfe position versus time graph of th9, d2albofhgoiq(2 v4is object is

  An object is moving with cons,w,x7 *t6mnpyatc xi;tant non-zero velocity in the +x axis. The velocity versus time graph of this objecx 7,n xtwym*pc6ia,;tt is

  An object is moving with constant non-zero o1qcbq3n2rqvd v3te.sw0p 85 acceleration in the +x axis. The velocity versus time grav52dce q3qbow.8s pt q3v01nrph of this object is

  The slope of a position versu)6c)vug3le,*bdz l9frrr fv 2.j4yjjs time graph gives

  The slope of a velocity versus time graph g qqz s0gojf,98ives

  The area under a curve in an acceleration versus time graph givomf 7ooy) nu4 a6yh92ves

  The area under a curve in a veloohjt,ci2:py3btcv i. 1; we9w city versus time graph gives

  If the position versus time gw im0 mla,/7vgraph of an object is a horizontal line, the object ia,mgl / 0w7mivs

  If the position versus time graph of an object is a vertical line,/8 o;kcm cn(fgq;:mk )mcf*9i5nydrl the object iscln8c9ymg;;rqcdn :( k5o f *ik)/mmf

  If the velocity versus t80e; x rgy.0ifcd7tg dime graph of an object is a horizontal line, the object gxe0y ;.igf c d807dtris

  If the velocity versus time graph of an object is a straight line makingrsckx( ft ,w5q;eg (8a an angle of 30 degrees c ;8(e, tws(fgq5akrxwith the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both the distancenreu:( a6ka 9l traveled and the magnitude of the displacemek(a rn:au9l6e nt vector.

  A boat can move at 30 km/h in still water. How6:lu/ j8an uo2ux 5azn long will it take to move 12 km unlauj6n8 ox5/uau2z :pstream in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1rlj ,53) cjkh ;n-ibx0 bw ::dtyrhnv2 mi = 1609 m)

  What must be your averatuq:s 7kp t wo1u6-(1oe6 eelvge speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42, d ksrm vjf6awre.h/k:r *)/x.0 km) in 2 hours and 57 min. What is the average speed of the runner inaw6hm*rkjek. r/ v/ f x),sd:r m/s?

  A car travels 90 km/h. How long does it take for it to travel 400 sg*0w gmvbx3z6o. su)km?

  A ly (light year) is the dis gka);hmtr)q u*(b2t x+ x9toutance that light travels in one year. The speed of ligho+*u)) xta gtxu; h2b( mqrkt9t 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 for 4.*3m2rkkdj/b ;nd-/b ixc dvw c/ i;sg90 s, how far do you tra;;s3d r gw/kbjc/id nv*/d2-xmickb 9vel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, yoe p;qfh3mz ui 3x1picw,3 6ql8ur average velw 3c3 mlh13z;i,6 pfqeiq px8uocity is

  A polar bear starts at the North P 0r)cc zriee0u(q2v:a ole. 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 tak)2eeau 0z :iqrrvc 0(ces 45 min. What was the bear's average speed?

  A polar bear starts at the North c-qmnwh- b-+lesbzcl7) xs+ )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 it--en- lsmc7 x shb+qc bl+))wzs starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weeken1gefp+c;/t aam;bl/ igw(s7 kd from school at 55 mi/h for 110 miles. It then starts to snow and y;a7lsiafem+ c g/k(/ wbt;g p1ou 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 1a y0vm0f4jexr 1nx,0 b60 km at 100 km/h. What is the average speed o4axfv01jm, be0rx 0 nyf the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h ;2v - 1fewt te u43;bow0lolbpand 2.0 h at 100 km/h. What is her average svw b4 uoo3t;pwltfl;10e-b2e peed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then ab6v3mv n ;da5kt 250 mi/h north for 750 miles. What is the ;v3b6v5kndamaverage speed for the trip?

  In a 400-m relay race the anchorman (the pehattj9 3.w7xp9-nxh mrson 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. Whx mhphnw-93jt97 .xat at 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 tv gwmm626whk39g3 zgn) q2k oho a stop after 12 s. The car's average velocity during deceleration was 34 km/h. What was the car's deceleration while slowimh69 mg2w qw63go)nvzgh3k k2 ng down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average rat0feyjd*+vet wbn y .b3;*9i mje of *byn9jbv.e+df i*3 mej tyw;0 $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km2s ,*clo3g;lngw: p jz/h accelerates 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 andzbwyuwpf bi,r 2j)gcy2;; 6*a 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 s. Ityyj8lx k )0+im rrf()puw rz70 then speeds up with a constant acceleration oy87(0uf)rm w ri)zrjlpkx0y +f $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 1.1 m/s experiences a bziaj h5(v,3d constant acceleration ofiadz (hb,5v j3 $1.6 \; m/s^2$. What is the cart's displacement during the first 4.4 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of 25l6ypm qb5-;*x5d lc js(plgm 06 m/s striq-5gcd yj pxp6m50(b lllm; *skes a sandbag and penetrates a distance of 28.23 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an ai )vk5/kyaraqh *pd,:rc r 6fs3rcraft carrier. It reaches a speed of 42 m/s at the end of ,r6 dhv r53 rkys*c)aa:f/ qpkthe 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 acu.yx 8 i-.(cqkglry 6kceleration 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 20x 0dnhpy ),.9peorge 9u5j.tc 0 m. What is its average accele0 hydo.xp jcr95 e9g, t.eupn)ration?

  An object starts from rest and undergopkrr+iu) vs8/es uniform acceleration. During the first second it travels 6.6 m. How far will it trpvui s k8/+)rravel during the third second?

  An object is moving in a straight line with constant r:rr4f9t4vmsacceleration. Initially it is travsmfr rt4v9 :r4eling 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 unifo,uard wtenr** 9was:fw-2n0rrmly 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 canx 51if.peza5ehb/ /oe0hynd64s q-ye decelerate 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+i dmci9 2,jtzizqbd:eg . g.4 turns green, a car that has been waiting at the intersection starts ahead with a dme .4gctz9. +bd,iiji:2 gqzconstant 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 o5k 6 )ple-qn, pcy0odof planet X where the accelno5 l,qc )k6 edop0y-peration 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 the surface of plana7/4vz0xhpplb+2 o61up kr llet X where the acceleration due to +/pv1pzu42bp6hlak0 xor 7 ll 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 oflvbq1z k -ljwc2pm6)6 15 m/s on the surface of planet X where l j6ql2z1cmb-w)6 p kvthe acceleration 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 ociyspkhh7*7k 2m.izn ;9 gh*e n the surface of planet X where the acceler shp *me7* hh;79gkc.iiz2nykation 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. I j , cxizuyf(:xh55m.if your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler toi,5yx(i : zhxm5juc.f fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its vezw 02 w vusr/du/x3ys.locity after 3.0v 2rs3u/sz yd/wx0 .uw0 s?

  A bullet shot straight up returns to its stz xw o3, 4z9xs*8kliz9 miz/odarting point in 19 s. What is the initial spee/, * ixsmx 3z99owo klz84dzizd of the bullet?

  A ball is thrown straight up with a speed of 36.z*.w 7 ooo*x zr da*,tzywj 3xr;a(z5z0 m/s. How long does it take to return to its stazwj 5,7ado*3 .*z;xtz yazzx* ( wororrting point?

  A ball is thrown downward from the top of a building with an initial q)cz :zfyec96 *i 2o6)rqtlynz 1-orvspeed of 23 m/s. It strikes*- lqn )6fo :)r26cvreizozyq1zyc t9 the ground after 7.7 s. How high is the building?

  A ball is thrown straight up with a speed of 30 mpx; o.ceh*9dx fqb ,:t/s. (only fill in numerical value in the qt9o:.; xe,cpxh d*f bblanks)
(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 injno. u:c;/i gwto the air with a speed of 28.7 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 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;bk*vrbgr6.bks i 4;e t = 1.0 s?

  In Fig. below, what isumps .6y 5n7jic.39jk0k wu qp the velocity at t = 2.5 s?

  In Fig. below, what is the velocity at ) d kvl 6xki)w)(lriui p:m(l)cduu x0z.b58k t = 4.0 s?

  In Fig. below, what is the velocity cb8 t.b ce5p (x/z)(vl.faqh:yc z ar1at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to 4.0i .p6us yo(y8tu 6pl4acqz 6t8,9wmz8kn yc l0 s?

  In Fig. below, what is the average velocity from 0 to 6.0 s? ody q1.8isxq k5 ht 9)fbklj9ct,8h4e

  In Fig. below, what is the a677o 1ovn rkc u)4qrgjcceleration at 1.0 s?

  In Fig. below, what is the accelerbxw-6g mi) 5xbation at 3.0 s?

  In Fig. below, what is the average acceleration from 9t0xkf4v (+ayz:+ fg:yvqs rg0 to 5.0 s?

  In Fig. below, what is tga*.;it tvvt6he average acceleration from 0 to 8.0 s?

  In Fig. below, what is the diccbtkdm( ;t9y)a, a :msplacement from 0 to 8.0 s?

Does a car speedometer measure s:hr4xjfwfr ;5gj) x2npeed, velocity? {speed|velocity}

  An object can have a varying 45/b pxeebh ;fspeed if its velocity is constant.

  The velocity of an object can be negative when its acceler1qy9rha 0 dqf,k 0x)-2rmquroation is positive.

  If one object has a greater speed than a second object, the first must hav;vobd.q6oc90: pxprz 6jrj nn3e4u m5e a greater accelerat b 9z. :4cxj0rvpn5;u36 eopqm6jrdonion.

  Two cars emerge side by side from a tunnel. Car A is traveling with a speed o9t klfq1.u fz0u/8gw nf $60 \; km/h$ 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 de35;o4aw e ge+ rwla-njcreases.

  A baseball player hits a foul ballwi t- 7hhi ,o//o6nuqi straight up into the air. It leaves the bat wi, iiuo tw/iqh/n7 ho-6th 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 is happening t(n cyqs(v /)ga-z+1szov2 * i7lpfjbl o its acceleration, how does it change if air fricti avnlip-* lfq cs z2/yj7go(s)1zb (+von is ignored?

  As a freely falling object speeds up, what is happeni6p n/a te i9o(bnzk-(fng to its acceleration, how does it change if air friction CAp(on f(ainb6-ze /9k tN NOT be ignored?

  An object that is thrown vertically upwardyi:c.y datb(4j0upqrpf o) 9)6gs4 ks will return to its original position with the same speed as it had initially if aiyb cup t4j d).skf(:y46i rg90s)aqpor resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero ve j5r1p 62rbvtcqy nc4g*oo)s ,-sz9exlocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleratqvq *wy/.om*oion at the same time.

  An elevator moving from the seco-ey y3)t+s5fm ;ahwky nd floor to the fifth floor making no stops along the way has zero accel3- w+ ysfekyay5t;h)meration all the time.

  A rolling ball moves f03qhx- aop 9lsrom $x_1=3.3 \mathrm{~cm}$ to $x_2=-5.7 \mathrm{~cm}$ during the time from $t_1=1.3 \mathrm{~s}$ to $t_2=5.2 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.8 \mathrm{~s}$ is at $x_1=2.3 \mathrm{~cm}$ and at $t_2=3.2 \mathrm{~s}$ is at $x_2=8.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarte h2f wk+u jro4kik-+*hr-mile ($1 \; mile = 1609 \; m$) track in a total time of 10.3 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away frol zy2psmu qx)z ()+pe6m its trainer in a straight line, moving 115 m away in 13.1 s. It then turns abruptly and gallo6lzzyp() + pxe sm)2uqps halfway back 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 frj.e9 m2;1nquzg jc(u2de- mwj om $11 \; m/s$ to $24 \; m/s$ 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 froa1y v d:t8,zitx 7h(4qyle.ap m $22 \; m/s$ to rest in a distance of 83 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must re vpmboexxrv+7y.s4g) wo n,h87,t 1xlach a speed of $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.8 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the bloco p.ut9 1k3ubymw 2) )uv6xfwvks to essentially top speed abouo29mv vy6ubw )tpw1 f 3u).xkut $10.1 \; m/s$ 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 fro orr4 z,jrd;z/m a speed of $18 \; m/s$ to rest in 4.84 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. Assumintrd y yb*:nk ,q41m4,dma)s tyg a decm)y,144k*ry, yattd smbqn d:eleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goinfl13jndg,o q ig s-ubx,t** f/g $25 \; m/s$ 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 to-f;t+ 4nbgcvn dvn 71he 10,000-m run in less than 30.0 min. After exactly 27.0 min, thvb ndg;no+7cnt4 f- v1ere are still 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?    $s$