Suppose that an object travels from one point in space to ano( 9 .igym0wtl l5jkl63oju-qf ther. Make a comparison between the displacement and the dwmljt9j3 l-5gyif0q 6.(kol uistance traveled.

  When is the average velocity d :oyg8qpco xt74jgzx t9q,1 7of an object equal to the instantaneous velocity?

  A new car manufacturer advertise ,w a/tc6fo9bes that their car can go "from zero to sixty in 8 fa69oec tbw ,/s". This is a description of

  An object moving in the +x axis experiences an accelerationxr -u ,ohsblx: (6eru6 of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow dos si-4von21g nt+v d1own as it approaches a traffic light. Make a stavng2v- t11o ds4nois+tement concerning its acceleration.

  Suppose that a car traf6gy5 eip2dk 6veling to the West (-x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleratii6yd2ke6g5f p on.

  Suppose that an object 4q.mg ) u7libqmjf*j u2:k4yy is moving with a constant velocity. Make a statement concern2mjqj kg .q:)b 4yul7uf *ym4iing its acceleration.

  If the velocity of an object is zero, does it mean thatf teha ):sfo3dc:+ tb0 the acceleration is zero? Support ybtd+3 0 fch:fsaeo)t:our answer with an example.

  Can an object's velocity change n*41p)itd. oxdx b kk4direction when its acceleration is constant? Support your answer with ad4 okdtk1b)p *xin4. xn example.

  Suppose that an object is moving with constant acceleration. Make a statement ;me4 rqho*)1h3ogc2v uwjio,02wkc cconc q3wi0hk2cvr1c gu4, oj) ;2chmo*weoerning its motion with respect to time.

  Can an object have increasing speed while its acceleration is decr 7)/1e*acha d3lo ufcgeasing? Support your answer with 1g chuaa*o /7df c3el)an example.

  Suppose a can, after an initial kick, moves up along a sdj3 +d4xn,g fzmooth hill of ice. Make a statement concerning its acceler xzngdj4,fd3+ ation.

  Under what condition is average velocity equal to the average of the object's ink 3 ean(( gih cr,9odq7fvlm+4itial and final velocit9fq3(i og7dr+ n(eac mhk4lv,y?

  Objects A and B both start at rest. They blv6 eekiarowmc r ya*e :*ey+l(w*898 oth accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final speed of object A compared to that of objw(:*all +mo* c8ev86ae ei y9wk yer*rect B?

  Objects A and B both start from rest. They0b et gl0hnt k5)cwk,y(-nm d6 both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by objeck)gl-mwc00b ke(h56n,tt dny t A compared to that of object B?

  When an object is released from rest ann6t0jtni.gyfc6a w / 3d falls in the absence of friction, which of the following is true conceynct gj wan.63ft/60irning its motion?

  When an object is released from rest and falls in the absence of friction, wqc*:szlj ,s d*hich of the following is true concerni :ljsqz,c ds**ng its motion?

  Suppose a ball is thrown straight up. Make a statement about therbsi ;+v.c rp7,f (sfl velocity and the accelerati,7l +(r si.psfcvf br;on when the ball reaches the highest point.

  Suppose a ball is thrown straight up,/prqcd5j +mjvx ( j7ve3b 7yf. What is its acceleration just before it reaches i+r7 xc/dbvm,p7eq( 3jjy5j v fts highest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then fallmqunf11 v b* ab09xlx/s to its initial height. Make a statement about the direction of the velocity and acceleration as the ball i0u*1 va1f /lxqb xm9nbs going up.

  A ball is thrown straight up, reaches a maximum heightnrwpgeor4 516ho z vyd;x 1f.2, then falls to its initial height. Make a statement about the ;r16f4o 5h1gpwo2v .yrzxd en direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the +0q ftb7)d :woh-r1xd :qaav dabsence of air resistance. Make a statem+ xa : h)oqra7tfb: dd0dw1v-qent concerning its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her acce,b vvf)z we6a+leration when she she reabvv,za6ew+ f) ches terminal velocity?

  A ball is thrown vertically upward with a speed4 ebc utd xu eha*,;xjwyg*88+ 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 first ba dh4*ub,8 cagw u8ey*; xextj+ll?)

  Ball A is dropped from the top of a buibu0w.ti5y*8zdbwuv6 csq c wx/g f5(5lding. One second later, ball B is dropped from the same building. As time progresses, the distance between them55w * ug0bbi(czc5v fwyxu6q w8/sdt .

  Ball A is dropped from the top - 9wwzadbvi.+ of a building. One second later, ball B is dropped from the same building-bzd 9i .wvw+a. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall boi0o9 p 7f)prjuilding. One is thrown up, and the other is thrown down, both with the same initial frp7o0po j i9)speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a b0+ui.w(( ygln z xu(hfryrr*6uilding. A second brick is thrown straight down from the same building. They are released at the same time. Neglech+ uu6zn.((il rr(*0fxw ygyr t air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +xp0zaa3 0vfo 1r axis. The position versus time graph pvr 0a1zao f03of this object is

  An object is moving with constant non-zero7()36r+0 ldxms iidl wfarrv/ acceleration in the +x axis. The position versu/lsw if 3arxr )+di6r07(v dmls time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. r.e:+ o e aighz5.gt3kThe velocity versus time graph of thigt +geh.a:.5ro zke3is object is

  An object is moving wit ucve +ddy5ko0h-)av3h constant non-zero acceleration in the +x axis. The velocity versus time graph of 3h ya+oukvc-d) v5d0ethis object is

  The slope of a position versus time graph apsx3p *e 7kw*qu*bk7gives

  The slope of a velocity versus t:fgr qo/yel, zxw/w,+lrt7 . nime graph gives

  The area under a curve in an acceleration versus time graph givyg ir kbifb4n)y9a(zg1 2k4-m es

  The area under a curve in a0 0ymo nltqr9 b,h0ye(a h*/qa velocity versus time graph gives

  If the position versus time graph of an object is a horizontal lin ib jevc hqlsv6a2*-+/e, the object b+vsj iq6 e *l2/hva-cis

  If the position versus time graph of an object is a qe-a u786j3r8zdqzyevertical line, the object is-3d7azru q8zjeqe 6y8

  If the velocity versus time graph of an object is a horizont,yc(dqe*qgn uvbz kqui v6 80y,t /9:qal line, the object yqk9 i tyeq vgn:qd/, q0u8b ,cu(*v6zis

  If the velocity versus time graph of an object is a straight cw2lnb q5h,g/ex6+jh i (x5ailine making an angle of 30 degrees with tc5 e+ b5 iinxq w/a(glhhj,26xhe time axis, the object is

  An object moves 15.0 m north an 9b ydzk,a -nqe1az/vm o7h-,md then 11.0 m south. Find both the distance traveled and the magnitud-e/ v 1mhzd, k qy,zoa7nm-a9be of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it take to move fy 5h+dt 5m/iqd, 1ivkil ccj*4a9s :q12 km upstream in a river flohslcc9mki : 1ty qjidaq,+54vdf5 /*i wing 6.0 km/h?

  55 mi/h is how many m/s?k4jel6r(fz: a 1zpry8:q9 zay (1 mi = 1609 m)

  What must be your average speed in order to travdrek :0 (c uqs9pm0,+tr/xbgdel 350 km in 5.15 h?

  A runner ran the marathon (-b(mp9gy os*ql)0 x5ol z-d xkapproximately 42.0 km) in 2 hours and 57 min. What is the average sped-s*k 0xo mlp b9)y5o-(gq lzxed of the runner in m/s?

  A car travels 90 km/h. How long does it gi.lf 1fr*n/btake for it to travel 400 km?

  A ly (light year) is the distance that light travels in one ye cotq.nglg.bw : 9rc:,ar. The speed of light c gql:ot .b:ng.9c,rwis $3.00 \times 10^8 \; m/s$. 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 t qi/d5i07bayu( o fjzaj3n.f 22+u-4 dmnstn you look to the side for 4.0 s, how far do you travel during this ina zu0 4bfn2+tjfq2n3j5-(y suo tdd/nmi.ia7attentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, n4z -ygr r../u)q8j + uf0(dvsl guedhyour averag.8n0ud/rs)jrgu4 heug(+d- v.fq zlye velocity is

  A polar bear starts at the North Pole. It .9x2nv7stibu5ui vf ;travels 1.0 km south, then 1.0 km east, then 1.0 km north, then s t fvxu5iv2;b. i9u7n1.0 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 km eo dyuez9 ufrd.kck- e)5yp7: 9ast, then 1.0 km north, then 1.0 km west to return to its starting point. This trip dd ypy.599c)ko7r e-zfek:u u takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend.4jfgo*)kxz.mys ns ++3ysmg1:lmq*a a9b ah 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 and 15 minua4g s*xy+mzfl jgk 1:qy9bos +3a)ms * ..manhtes. How far is your hometown from school?

  A motorist travels 160 km at eld -xpmn8vr: up+z1dir5a) 880 km/h and 160 km at 100 km/h. What is the averag x+vr)5mpiranlzud e8p-d 1 8:e speed of the motorist for this trip?

  A motorist travels fd 7u5)kghaqbe f5/ 9boor 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her average speed for the tr 5a f75/uheqg bok)b9dip?

  An airplane travels at 300 mi/h south for 2.00 h uo2 n dyjs0pan8jjq zz*e ;d.604s vc+and then at 250 mi/h north for 750 miles. What is the average speev0uzajz+*e s2c;68ndnds op jq 40.jyd for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for te8 sh+uz,k 1zhlaklu+z1,sh8 zhm 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 lose the race?

  A car decelerates uniformly and comes to a stop after 10 s. The ca51(. +ffz jb,gs.vt qdj7ukzcr's average velocity during deceleration was 31 km/h. What was the carfj1c57zsv+.qz (,t f g bkdju.'s deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 16y (ig u vw5-2i7wqyqx(0 m/s, at the average rate of 7( qiy-5qw2 vixg (uyw$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at mi42+s pxy ww(n x zoj7m5ta8(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 rb4h 3iwh1 plse l83-(rhh b2 w)lpi6bdest 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 forpzpy :. qo/q5h 10 s. It then speeds up with a constant acceleration oz5q.y/ p:hpo qf $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 2.9 m/s experiences a const c12mbeh t ):*qgsgr oqf9z8)b a-8ztzant acceleration of q z t8f:b)2 zhc1gb-9e*m)st gzo8arq$2.0 \; m/s^2$. What is the cart's displacement during the first 5.8 s of its motion?

  A bullet moving horizontally to the right (+xpy/aw1soc)c8 hq 36v .s4m qfbzi/ 4ad direction) with a speed of 398 m/s strikes a sandbag and penetrates a distance of 31.32 cm. What is t61/o 4szc qf83ah vc/a )4piym.qw dsbhe average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launcxhhhnsg 5.4 v-hed from a catapult 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 length of the cahhg4n5.-vh x stapult?

  A car starting from rest moves with constant accelerationd*u r:uo d*8myhfn9qi(a g+d: 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/;5wthm .doa (ms to 80 m/s in a distance of 200 m. What is its average accelerationt;a. wm(od h5m?

  An object starts from zszl:ksq+h0 v;f22z;xc p 0 akrest and undergoes uniform acceleration. During the first second it travels 3.1 m. How far will it sk0 x;2v0zh p2lqak;zs fz+:ctravel during the third second?

  An object is moving in a straight line with constant acceleration. Initk atlms3,unxzx ; o*-e(/xt,xially it is traveling at 16 m/s. Three seco-;/ 3l *kteuxatz mns,xx,( xonds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates unizhisjlp5q4,q6f ,; u5iubc (hformly 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 decelerate at abo-vlr- zly-/ kft0ix)yut $5.0 \; m/s^2$ 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 waiting atbe8 ux3 v-y4vt the intersection starts ahead with a constant acc-vbtexu 4y8 v3eleration 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 o) o +c(wdy)- bxwil.cm,m2h mkf 12 m/s on the surface of planet X wheremloch,(d mk2 -m. cw)yxbw+)i the acceleration 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 oyr upv9do 07a1f 12 m/s on the surface of planet X where the accele71 roy0p 9duvaration 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,yq-)mja w1h5s ag-ie a speed of 15 m/s on the surface of planet X where the acceleration due t qjg5m y,)1 -asaieh-wo 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 planet X wy;/+ n/:p)xy rgixq vjhere the acceleration due to gravi+jnvxgr )p/;yyxiq: /ty 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 friend hol71i9-* b+o w+rjf,c(jxpjqnlo go9sn ds a ruler between your fingers and releases it without warning, how far can you expecwjf-no+(j or,i9pb*co qg+ 97 1 xnsjlt the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. t-ui1noeiw 4cu/0lm+ What is its velocity after 3.-1iwmcet+u i /4no ul000 s?

  A bullet shot straight up returns to its starting point in 12 s.ul7/7l1q j pfr What is the initia lf7/qup1jr l7l speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does ,znnb (, e:o z pc-bvf o8y/u.v+ 8rdci*mofy8it take to return to its st .rnv8c8y,n: oi,z(b -v8efpmu * f/byzdo+coarting point?

  A ball is thrown downward2j)ltf8t u t9r from the top of a building with an initial speed of 21 tt9jl)2uft 8rm/s. It strikes the ground after 1.5 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numeri8 dh fyrimhz(gi:hvj*)t 5s y6hz*u+ ;cal value 5t+ 8 yz*iuy)dj;sg(hf h* 6mzh hvr:iin the 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 wh tset0s e 9+mq6pp3j)ith a speed of 49.2 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 9 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 9.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t =::u. 0vdi1 7 mtgmn+nm7rjawq 1.0 s?

  In Fig. below, what is the velocity at llw/. k-j-l7-jv cslzqj0qp1t = 2.5 s?

  In Fig. below, what is the veloc mabf tu9;xc -,yo67uqity at t = 4.0 s?

  In Fig. below, what is the veloci ; rw8ctrl x07r*-qhsfty at t = 5.5 s?

  In Fig. below, what is the average velocity fr e7b m hl4gh5x6;cvif8g y(sd7p4k9zlom 0 to 4.0 s?

  In Fig. below, what rm gqx j 5m8ltbqnq :7mvs2h;y)+ e;+dis the average velocity from 0 to 6.0 s?

  In Fig. below, what i1rq ckdr+ ti- v1+mq:7w bc4 c7gq:nzts the acceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.esqr:nj g598mszewfg,u+ jp2udpp gn.j. 416 0 s?

  In Fig. below, what is the average acceleration from 0 to 5.0ir, -h-wtn0h 1h ob-yq s?

  In Fig. below, what is the average aco2x.sz d77b7fgtoe::p( lirk celeration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to 8.0 b,8ls/n15l/ +0 ;bn gvqi;msfwi z yvss?

Does a car speedometer measure speb ze15y4t4szwx5s62n3if ml zed, velocity? {speed|velocity}

  An object can have a varying speed if its velocity is con.bw ae375td eastant.

  The velocity of an object can be negative when its acceleration is positive.8 o;ifyz8er12r(ph qz

  If one object has a greater speed /3 /fij2whk(tvsbnx (than a second object, the first must have a greater acceleratn 23fw x(h(vikb js//tion.

  Two cars emerge side by side from a tunnel. Car A i 0 00)2wbwu kjghhc8qis 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 spi kfo 66 00dvkbt,.cnveed as its acceleration decreases.

  A baseball player hits a foul ball straight up into ipxq5z8x jp8ey7;1zk the air. It leaves the bat with xi81p75 x; kj8zzqype 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 ma0bt +(4s5cu qwol8eup, what is happening to its acceleration, how does it change if air friction itol0 a45c8eu(w +qbmss ignored?

  As a freely falling object speeds up, what is happening to its accezyc w+oe 2u;8wleration, how does it change if air f82o y;u+w czewriction CAN NOT be ignored?

  An object that is thrown vertically upward will return to its originalbg o+im4 w ,/jz3ynz1y position with the same speed as it had initially if air resistance is negligible. If air resistanceo/w1bn,i3gyj zy4m+ z is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration at th 9p;tj 767rde6xpk5r tuczd2re same time.

  An object can have nonzero velocity and zero acceleration at the same time g-m ( 9vlsrz9;w(iwil.

  An elevator moving fro9ne6nra fcvc+ nzz- k ;7m/sm5m the second floor to the fifth floor making no stops along the way has zero acceleration all efa 6/-z;rm+97znnsm5 nkc v cthe time.

  A rolling ball moves fr qoeh +6so6p-rom $x_1=3.2 \mathrm{~cm}$ to $x_2=-5.9 \mathrm{~cm}$ during the time from $t_1=1.8 \mathrm{~s}$ to $t_2=5.8 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.6 \mathrm{~s}$ is at $x_1=2.3 \mathrm{~cm}$ and at $t_2=4.0 \mathrm{~s}$ is at $x_2=7.5 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete lapsn y)z66c2g bm7t4c:-xrw8je (jnbjjr r1tu- t around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 8.7 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 1ej-5 bkxyzja3i* /7 xj01 m away in 13.2 s. It then turns abruptly and gallops hx*5z /bj7 kjj eya-i3xalfway 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 frqi 2ao.gb+x+xz0p x- cknv9 xi*sd,0hom $10 \; m/s$ to $22 \; m/s$ 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 froq(ewtw/ ah+30tzgz r/ m $19 \; m/s$ to rest in a distance of 66 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must r imnc s6870hkn 6z:qareach a speed of $33 \; m/s$ 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 can burst out of the blocks to essenti)uv x ogk3en.6ally top speed aboutk) n 6ovux3.ge $11.2 \; m/s$ 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 uniformly from f1ojq k9t.kr +qjra1,a speed of $15 \; m/s$ to rest in 5.46 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 hsgy gwgl0* qxy5u m7k1;kw6kn08h 3 pvighway. Assuming a decel3 0kw *;l ky1ys85guvpnxk q6mhw0gg7eration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck giiy5b f bu- 1+)fb pchrp+e51eoing $25 \; m/s$ 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 miugu(2wtiv j l9 * v8mrb6s)v)on. After exactly 27.0 min, there are still 1100 m to go. The lv uoig2s)bw 6t) m( j9ur*vv8runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$