Suppose that an object travels fr(k0y1 fud hj/khhh4vevka7d )8-9 djvom one point in space to another. Make a comparison betvk0kdjvv)7yhhdh 8e/(u91kdf a4-jh ween the displacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velocitj4d ehuua6.i5pg t2 -bp2yw.uy?

  A new car manufacturer advertises that their car can w;n ktmht-(rz927yr/ y, azz)ldkll wu 8a(l7 go "from zero to sixty in 8 s"2(w)rt-7/ z78(y w rhtzl9l,k m; yulanlzkad . This is a description of

  An object moving in the +x axis experiences an ab6ufe 1/ /1pvb v yswxu088qcecceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (.-vvbvmj amf.*z 7f7 /m 2rxdh+x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its accelerati/mmfv.7.2az- jb*x rhvvmf d7on.

  Suppose that a car traveling to the West (-x direction) begins to s 8 vx-(-nmmpz(/.. jgftnacue low down as it approaches a traffic light. Make a sufn((/ac p-ezx. mj.gn8vm -ttatement concerning its acceleration.

  Suppose that an object is 48 mogr)28; s2nvqs6/a rxi fwoeus-w moving with a constant velocity. Make a statement concerning its accelerat84 xor)ns2 f;2-as8urqgwm 6iow/v e sion.

  If the velocity of an object is zero, does it m:o(4x4dby49yvm cj(el42u b1shss ftean that the acceleration is zero? Support your aec( 2sy 9:ltsym(4uohsx dvf1j4 b44bnswer with an example.

  Can an object's velocity change direction when its acceleration is c4hxgso a be9(a0.1jp+4taaj h onstant? Suppoa+sb(0 g h4eaj1jxap at94h. ort your answer with an example.

  Suppose that an object is moving with constant acceleration. fkbml icot6hous6:n3g m2) 68 Make a statement concerning its motion with respect to t6nh 6 g82sb itum:3m o6)olkcfime.

  Can an object have increasing speed wh7/t,;lg+ vo n8;avwps+y xbc bile its acceleration is decreasing? Support your answer with an examv/+ xoa,p w;b 8tcvln7g;syb+ple.

  Suppose a can, after an initial kick, moves up along a smooth hill n4uyg85w/4da :5y hxmg h 8fggof ice. Make a s/5hxggyn4amg8w h dfu48g y5 :tatement concerning its acceleration.

  Under what condition i;lsng,)uxe m 2s average velocity equal to the average of the object's initial and final ;2l xu smneg),velocity?

  Objects A and B both start at rest. Thelbh2 gzd4p d/,y both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the fi,b2/hp4 z gddlnal speed of object A compared to that of object B?

  Objects A and B both start from rest. Tx1x+r,27xwj ty6+rod;z i mqihey both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object tr6 xdow +mx+1xq,y2rzi;j 7 iA compared to that of object B?

  When an object is reey n 0p133kwljwfi*f 6leased from rest and falls in the absence of friction, which of the follow l3 ef0ipjw fn6*1y3kwing is true concerning its motion?

  When an object is released from rest and falls in the absence of fricib25k+hi buv3 tion, which of t 23ub ib5kh+ivhe following is true concerning its motion?

  Suppose a ball is thrown st-:4g g ,bi 9x kdnsjb7qrg *knm/obzgv/.kr)2raight up. Make a statement about the velocity and the acceleratg)2b7/*/v krnmg bnbrkid-q:gj9g.k4xo, szion when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is it2 qwi+a,ayt8sa6 * xlps acceleration just before it reaches its highes s6t28aq,yaxipaw l+*t point?

  Suppose a ball is thrown straight up, reaches a maximum height(d3k hb0 ym/nm*rz 6hz rmhc2/c.isz :, then falls to its initial height. Make a statement about the direction of the velocitk./zm dsh/*rby:z(m2 c mh nz0cr63ihy and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a ebe3c2 ;uwpy jz,dc1*maximum height, then falls to its initial height.e, ;2ec *pdbjcyu1 3zw Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward i 1u7h/tlct epxl))1qr n the absence of air resistance. Make a statement concerning its7t)xl/ e) up1 thrlqc1 acceleration.

  Suppose a skydiver jumps from a high-flying plane. edm,wgjh3le yh 2+d:aas. (s)rb uqq9zk,6i,What is her acceleration when she she reaches terminalgk.zlhdd be,i9)shwq mu3,aq:yesj, +ra 6(2 velocity?

  A ball is thrown vertically upward with a speed v. An idemuwj(5h3 5/mwhq7sdoc .z7.3zppq z xntical second ball is thrown upward with a speed 2v (twice as fz q3q./ pm5zo3u mx j7wphh.dzc7(sw5ast). 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 og.qtnt6h c2d; f a building. One second later, ball B is dropped from n2c ;.g6qtdhtthe same building. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One second later,gte/i/ vmx;1 jbz9m-q ball B is dropped from the same building. As time progresses, the difference in their mtei 1g;-9/ jqx z/bmvspeeds

  Two objects are thrown f,9 ipcyapt/1:9/ja ; zgy.zo tkumud-rom the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What a t a.9o-gcu/p, du/ z;y 9jtmz:pyk1iare their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown stra3 ap (r,w8m* e)hbp5tnpoc fl,ight down from the same building. They are released app,8fn(a rhw,5 ol3etcm)bp *t 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.ag jgb/ffu r6mt7,5a. The position t. f6rm7/b5juaagg ,fversus time graph of this object is

  An object is moving with c89cof7wasf,iq 3or i+onstant non-zero acceleration in the +x axis. The position versus time graph r,w7q s3c8i o aifo9+fof this object is

  An object is moving with constant non-zero velocity in the +x gl )ex1i2)e gnaxis. The velocity versus time graph of this i))elg 2g nex1object is

  An object is moving with constant non-zero acq)v 1 56ulfptnsa5ci/celeration in the +x axis. The velocity versus time grapptqu/lfa515 i v)ns6c h of this object is

  The slope of a position versus time qig sli k/0v*o w,r0.ugraph gives

  The slope of a velocity versus time graph 0ou2bvvj wqmky)y 1iqd45(it,a: )ucgives

  The area under a curve in an acceleration versus tidq82uaf n4x v4me graph gives

  The area under a curve in a velocity versus time graph gi : dwms9l3teg wkw,7piqv72h85oxh/vves

  If the position versus time grl+djm*rmbwz/ndp9 e z6 ./ v5xaph of an object is a horizontal line, the object d npz6vjbx /d+e/5m* wzl9mr.is

  If the position versus time graph of an object is a vertical line,.ayzyh ujoa97mvav3)i s 7.v7 the object iss i va79ay)y73h7ovzua .v.mj

  If the velocity versus time gamwd:t-e *te6raph of an object is a horizontal line, the object medat6wt -e*:is

  If the velocity versus time graph of an objecm yo1tzi+ 6arq+chu(*t is a straight line making an angle of 30 degrees wr mozuh +ic+16*q (atyith the time axis, the object is

  An object moves 15.0 m north and then 11mr+z.w7;mc fj .0 m south. Find both the distance traveled and the ma;7j. fmcmw+rz gnitude of the displacement vector.

  A boat can move at 30 km/h in still water. H:vpt rlg: r ph6g g.eqg99bt8+ow long will it take to move 12 km upstream in a river flowing 6.0 km/h? 8 g:tq9l+gt6g g rp:br.ehvp9

  55 mi/h is how many m/c n dc4ny1x57eni(:+pgmx:w ps? (1 mi = 1609 m)

  What must be your average speed i 91 otdjxq /0vz,s;uoqn order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 1 tlyo5)z i cuok( uq6m-z8aj/min. What is the average speed of the runner in m/s?6m1/ij luy(kco 5z-zqa8)o tu

  A car travels 90 km/h. How long does it take for it tnq+ i.x0tfw2cn: qyfjinhc /a )4f1+ ho travel 400 km?

  A ly (light year) is the distance that light travels in one year. The speed of /kpnv 6 prba wn,tbo./w4h:l)light 6bo/a ww:nt)4n phkp .vl/r,bis $3.00 \times 10^8 \; m/s$. 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 rom)*b:l )dny0:0 hn7aqmwczdpad and you look to the side for 4.0 pm))ban zn0dc07q :l wdm:yh*s, how far do you travel during this inattentive period?

  If you run a complete sj 0hs1;qm6ctsdcf+ 3:- d lzploop around an outdoor track (400 m), in 100 s, your average velocit 13ddq:0+t hl cspm6;zcss-jfy is

  A polar bear starts at the North Pole. It travels :jxali(pv .6k1.0 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 beark .iva6(p: xlj's average speed?

  A polar bear starts at the North Pole. It tr :iqpcuqo m:;m9 f5,vxavels 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 beau: oqfcxmv,pqm :;i95 r's average velocity?

  You are driving homesx5ovz fmqo 6x 5zj741 on a weekend from school 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 an m7 f1sozvoz65 45qjxxd 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and8o /is h75p-h6 ta wrqeu97cpg 160 km at 100 km/h. What is the average speed of the motorist pi8 ht7/rgahw 576qs -9p euocfor this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h abq qhar44m:fy xn g7)ss5)tt 63q*rcet 100 km/h. What is her average speed for the te6*htfn)q:s a4 r43qxtys qm b)7rgc5rip?

  An airplane travels at 300 mi/h sy.ke y:2q.s1sool 2gsp4vz) u outh for 2.00 h and then at 250 mi/h north for 750 miles. What ips1y :ev y 2)4l.zk2oos.sguqs the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runbb5k u54ar2 yes 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 b5 4b2a ury5kelargest 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. The 38t42,ynusmpj zve n 5car's average velocity during deceleration was 5852sez3jtup 4 nmy vn,5 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/.)(g s(c dw/f6 wqduods to 160 m/s, at the average rate of o) /g.ufwwd(s( ddc 6q$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at th)uf ncbvk wpm5n2*/*oe 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 aj 0 jt/cccb8d(nd 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. It then speeds uqj 0h.kun6v ep 5 m-bco9hfp,oc2s9+dp with a constant acceleration 5jmvc0onks6upbqhh -ed,2p9 co f+.9 of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 1.3 m/s experiences a constant accelerationfq:r q* lrx6 xd9b7s4z oq*9:6zsxrd rf7 lq 4xbf $2.6 \; m/s^2$. What is the cart's displacement during the first 7.1 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a spqe)qb(ppt1 eas+wwt6by33j 7eed of 322 m/s strikes a sandbag and penetrates a distance ops3wa6 tj)w(q eq3 1t7pe+ bbyf 50.95 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapultk j7es 68poye1exc1) z on an aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the lengthjs) pec 1ex6y eok81z7 of the catapult?

  A car starting from rest moves with constant accelerapolqw tlh-w2d * )wr5y 62ojb(tion 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 is its avera0clbe8ex7r, odw8r+p*ej +(t tpd qn+ge accelerarl + e+r8p+e t (x 0*e,dpto78dnqbcjwtion?

  An object starts from rest and undergoes uniform accelerationkp( dx4r.g o;n. During the first second it travels 9.9 m. How far will it travel during the nk;(pdox g4.rthird second?

  An object is moving in a straighd6 tb9n 4v*w .fl9vmzv 4dd:eit line with constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far do fdn:4t4ev 9diw*zb.dmlvv69es it move during this time?

  A car starts from rest and ac. neq;ab xfv6 :e7n99scj hby2gz (v)ncelerates 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 tireqiqm m31 w9x/g2zoee.s on a dry road can 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 turns green, a car that has be2grl-lqu2 *fm.l0ypr en waiting at the intersection starts ahead2ym l lgr0* u.2lpqrf- 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;lo;ja ) bamq3/s on the surface of planet X where the acceleration due toj)aalb; ;mo3q gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speqhammk6 g0 r 3dy7e86.6gccyoed of 12 m/s on the surface of planet X where the acceleration due to gravity irq a66mkd. cc gm680ghy73oyes $1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

  An object is thrown upward with a speeoj al*lr +dt021 d;iqkd of 15 m/s on the surface of planet X where the acceleration due to o0q2rd *alkti+lj1d ;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*: du9odllm 2a/s on the surface of planet X where the accele2 lamod9u:ld *ration 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 greateh 9ct ,uc q3brjb5n570,uop ddr than 0.10 s. If your friend holds a ruler between your fingers and releases it wi ,bdp 7 5h,bq9ou3rcnc5ud 0jtthout 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 is its veloci5sn fe,qa8*xxgxce:,ty after 3.00 s?cs ,*x, 58xeegf:n qax

  A bullet shot straight up returns to its starti ,hu 2y z7ohpy:v8:utqng point in 19 s. What is the initial speed of the bull hy7zou pt, 8h:u2yq:vet?

  A ball is thrown straight up with/wsc: 32 ufobf a speed of 36.0 m/s. How long does it take to return to its starti fs:w23/fuoc bng point?

  A ball is thrown downward from the top of a building with an initiaq5m4;k rcat,sh4 1cr: b+x7h2;7w bhtw pjanjl speed of 9 m/s. It strikes the ground after 6.7 s. How high is the building:jjtr;4ch bw 27xs5ahp7t,am w+q14kch br;n ?

  A ball is thrown straight up with a speed of 30 m/s. (only f60up ughy96gg ill in numerical value in the blang0hgugp96u 6y ks)
(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 v7onx tmj8y 0*the air with a speed of 33.8 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 1 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 = 1.0 gi/)qq s cvsu 06k,lm7s?

  In Fig. below, what is the vepcdc m(bag r20)l 8xf:locity at t = 2.5 s?

  In Fig. below, what is the velocity-akh8pq1 wuf-3 nhkm6cm0- pt at t = 4.0 s?

  In Fig. below, what is the velocity at t = 5.5 s93 0izg(a+sg-w:xpc - oo ozcs?

  In Fig. below, what is the average veloci..gs/efjz ,lqb8 ae7 hty from 0 to 4.0 s?

  In Fig. below, what is the average velocity from(dr l x47iwf22i zxub/ 0 to 6.0 s?

  In Fig. below, what is the acceleration24* fwuspisn(u zeh,; at 1.0 s?

  In Fig. below, what is ther8xm2y3t yh9r;ss. um/nfm 4y acceleration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 to 5.r zv;emvc(v c)3 e7;kk nmpw+80 s?

  In Fig. below, what is the average acceleration from (wbv0o;ch +qagi w a (gj1ju/70 to 8.0 s?

  In Fig. below, what is the displacemenf2 7s ln,/u agb0sqs /2leo,let from 0 to 8.0 s?

Does a car speedometer measure ub758dq e5jue x3o1gdspeed, velocity? {speed|velocity}

  An object can have a varying speed if its veloqtv txk;uahj0a v/ kh8f 5c9pv-s/v8; city is constant.

  The velocity of an object can be negatij*e iab0t 0jk2n+r5ou ve when its acceleration is positive.

  If one object has a gre5k3qx u4bf3vbater speed than a second object, the first must have a grea b4vbuq3f3x k5ter acceleration.

  Two cars emerge side by side nfs,x hj6ykx1c: 2 8 ievu9(yrfrom 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 acceleration decre32td+vny8gtf zcm *,hases.

  A baseball player hits a foul ball straight up into the air. It lejnd5 tsuvwf8 )/x(d r5aves the bat with a spewr )n8t ufsd/5vjx5d(ed 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 to its ac0tp98mk1i jw o/pamv;celeration, how does it chan0/89kt; wpmmpvjai 1o ge if air friction is ignored?

  As a freely falling object speeds up, what is 8f a61f zr;ptthappening to its acceleration, how does it change if air friction CAN NOT be igntfp;t zr186faored?

  An object that is thrown 4wkx/o( q20ys,vkf d hvertically upward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is h/0 vko2f4wq,x dky(s appreciable, how will this result be altered?

  An object can have zero velocity and nonzero accelejyw2pr a9t n45ration at the same time.

  An object can have nonzero velocity ncphrspqt x 0+26q .66nisin+ and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor making no fe/:qro(8ow sstops along the way has zero acceleration qoow(se:/ f8rall the time.

  A rolling ball moves frfy nrsq7b-;4l h.g6in,x2zco om $x_1=1.6 \mathrm{~cm}$ to $x_2=-7.1 \mathrm{~cm}$ during the time from $t_1=1.7 \mathrm{~s}$ 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 $t_1=-4.9 \mathrm{~s}$ is at $x_1=2.0 \mathrm{~cm}$ and at $t_2=3.0 \mathrm{~s}$ is at $x_2=7.4 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a qsriy qh w)rr(h*8x /5duarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 10.1 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 )cpd0*)7sjn,a g* i5h ,7rm vuo o/mxs:oja vka straight line, moving 109 m away in 13.2 s. It then turns abruptly and gallops halfway back in 4.spnxmaa*7u/kg v7,rj5o ,co i )sdojm0v)*h: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 fromwxr:ir*:f 63 +kmw dvi $11 \; m/s$ to $23 \; m/s$ in 5.4 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.po*.5ce l d.nhx j;ezm $22 \; m/s$ to rest in a distance of 56 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed of:c57vsh1rrshkk- x/ v $32 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.1 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter 8wx9gzu4 fp 7gcan burst out of the blocks to essentially top speed aboutpx7g8 g uf94wz $10.7 \; m/s$ in the first 12.4 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 sdpk 1 mz9zj dux*ma ck)31,k5fpeed of $20 \; m/s$ to rest in 4.74 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m wmcr,g6z/qy9 long on the highway. Assuming a deceleration of q zy/cg,r9 wm6$7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck go(j/9irymh 4 j m c8mgjrzv4(;ning $25 \; m/s$ 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 10,004 i(sradh m+t q,kqb iyb7)r.pfk*,0 a0-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then accb+0qmf(.tk ,* bariidpk)s 4, yr7 haqelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$