Suppose that an object travels from one point in space t z kf)j2wsg/d4o another. Make a comparison betwew 2 )z4jgdkfs/en the displacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneo asgo 6oqlyh ib33mt3 c1g66u6us velocity?

  A new car manufacturer advertisesvp u *d,froc6db71n z) that their car can go "from zero to sixty in 8 s7du r,1c vo*pbn 6zf)d". This is a description of

  An object moving in thex 7o*kn m:bz44akk3 xgrsj,r 4 +x axis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) j8iwaz7h ji, i/u tcn:)xu:8c begins to slow down as it approaches a traffic licx ):j jic:8 z 8/hua7t,wniuight. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) beginff1uwt i;o r lzg 2+6t:jr7+i/bm-a eccot5z6s to slow down as it apprt+g mewb6f1 7-:/r;oc t+r2o6 itauij lzc5f zoaches a traffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a cons9 dbyto lzhjh)zzh0i49 88 f/nx9vt1ptant velocity. Make a statement concerning xy9 t9t8oz/91fi0 vhnbpj hd) l z4zh8its acceleration.

  If the velocity of an object is zero, does it mean that the accc+ox 6 k3jw)pyx,g z-seleration is zero? Support your answo+yx czsgx 6-),pk3j wer with an example.

  Can an object's velocity c2tr g- k 6onwf8rlj-6yhange direction when its acceleration is constant? Support your ans6o 6r frlwgytj n-2k-8wer with an example.

  Suppose that an object is moving with cm mwxrehg6*65 onstant acceleration. Make a statement conce*mwr xg6m 56herning its motion with respect to time.

  Can an object have incre.ow+ml nxjqz .d-p+0 casing speed while its acceleration is decreasing? Support yourx.-q.p+o+c wn0d zml j answer with an example.

  Suppose a can, after an initial kick, moves up along af,u;h, m2arpv-wgg2qcwyd 43 x4*fhl smooth hill of ice. Make a st4rq2wmy ,x,fdag;h2-p43vf l*whcguatement concerning its acceleration.

  Under what condition is average velocity equal to -*cwxn(f0v4mlwb 4tkd )6:.nrc wqn athe average of the object's initial an4mc-vd0r nwnwa4xlc( t:. 6qf)wbkn*d final velocity?

  Objects A and B both start at rest. They both accelerate at the same ox*aln ,3t: dznf*ldbn9*( up rate. However, object A accelerates for twice the time as o a*nonnlz(*u p:f9dd *bt lx3,bject B. What is the final speed of object A compared to that of object B?

  Objects A and B both start from rest. They both accelera;/pyx:s tubsqf ut. x/1co)5n te at the same rate. However, object A accelerates for twice the time as obje t/uxycb s ).s5oup1:tx/n; qfct 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 absence67 ctimh-ntp: of friction, which of the following is true concernini-7tm6 nptc:hg its motion?

  When an object is released from rest and falls in the h1o qr/y)td */elcr 5qabsence of friction, which of the following is oy)51 qrl/ * ht/rqdectrue concerning its motion?

  Suppose a ball is thrown straight up.mv,)u 1ww56m kv qnfr8 Make a statement about the velocity and the acceleration when kwwr65f) ,8uvm 1mnvqthe ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its ajpi0l6 4tg.br,yerx0cceleration just before it reaches its highelb.p ,0eytg0r jri64xst point?

  Suppose a ball is thrownpeysdfrk+-1);v ne375( bkhzm /yrvj straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is -dfrk/nyv)ee3 (m7+ y 1pjb5kr hsvz; going up.

  A ball is thrown straight zqma zs(f7. r.9 mz;xnup, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity ;zazm(7 sr9n .fx.qmzand acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the 3) jix q3g2araabsence of air resistance. Make a statement concerning its ac arxgq2i33)ja celeration.

  Suppose a skydiver jumps from a high-flying plane. What is he7zeed z:y l zc02jh-voxm)74 e74tfko r acceleration when she she reaches te0 ctzvmoelkeyz)zh 24 x477oe :-fj7drminal velocity?

  A ball is thrown vertically upward with a speed v. An identical second ball i p0g.d 6x8qqj22eqzwvs thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of tj2v 2q g8d0q. zxpqe6whe first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from the top 9 x*/vznd rt 9w*vira)of a building. One second later, ball B is dropped from the same building. As timewn art 9d/r*9)*vivzx progresses, the distance between them

  Ball A is dropped from the top of a building. One secony ,b9r7 k6omx+xc-e pod later, ball B is dropped from the same buildin 7x-9 e,ooykb+ mcr6xpg. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall build dn,t9,5kp sgv f6u3pcing. One is thrown up, and the other is thrown down, both with the same initial sg,3,5nd 9p6psvu ct kfpeed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown st;hs2y)ppw bk* raight down from the same buildi*bw)shp2p y ;kng. 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. Thp l5cgkti2 4+ir(-nb 4ag;1;wmhynba e position versus time graph of this object 2+ 5bgn al4(mn p-ayg;; witkr4ibch1is

  An object is moving with consta uba v6b1we x:czqyf6;)rq;.sizo;0 k nt non-zero acceleration in the +x axis. The position ver zyafzbk w bs;rqqovi;exc 60:6 .;1u)sus time graph of this object is

  An object is moving with constant non-zero velocity in the +x t(voye; 25fbbqe ga2h a4- p*uaxis. The velocity versus time graph of this oby*q etpo4h( 2-vu ab;ag e5b2fject is

  An object is moving with constant non-zero accelgrr:f 7jo; zd0eration in the +x axis. The velocity ve f;7zgr ro0:djrsus time graph of this object is

  The slope of a position versus tiqx t-0akc: ,rime graph gives

  The slope of a velocity versus time graph gi)pr wk k/03sz*sbqx/tves

  The area under a curve in an acceleration versus time graphei/f:/n5viqzj 3 w7 im4c0lvh gives

  The area under a curve in afa -vs1x1gp8 k velocity versus time graph gives

  If the position versus time2( nrpz:rnrg* :6. svk1ww.)esdrsyh graph of an object is a horizontal line, the object is2sgvw knwz(rry 6* rsnrs.:)e: .1d hp

  If the position versus time gt ;upg*.ro/um, mu py0raph of an object is a vertical line, the object is.yp ur mp;tm*0/uugo,

  If the velocity versus time grap c(k:aoj 1 rll(e (nyp7ps)3kih of an object is a horizontal line, the object iln yl()sopkk( ie3(p7ac:jr 1s

  If the velocity versus time grf;gcxebs0yk e 4v1/2qaph of an object is a straight line making an angl xk/es gqvc;40e 1f2bye of 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 disf-*8hf qo;nr ftance traveled and the magnh; ff*8rnfq- oitude of the displacement vector.

  A boat can move at 30 km/h in still water. How iqj :;bi9u(hb c.kkq o/4ql-y long will it take to move 12 km upstream in a river flowing 6.0 kmi-hiqko9bcqy;bj/. ( lk4:q u/h?

  55 mi/h is how many mj b32q 3t6p 4vqu+bqpn/s? (1 mi = 1609 m)

  What must be your average speed in8,fixt* uqm :g order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours ano4ljg:/ rfj)02 w kjjpd 57 min. What is the average speed of th/42pj:frljjg0k w)j o e runner in m/s?

  A car travels 90 km/h. How long doesnku +:h4cttxg;w8nm(pv/ g:g it take for it to travel 400 km?

  A ly (light year) is the distance that 0(2*odx+c1dpx c r9ox )tvqiplight travels in one year. The speed of light v0pd x(coo 2rq+px)x*9ci dt1is $3.00 \times 10^8 \; m/s$. 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)/-t74 hue55 ng (pf hjaa+plj1iouupcwfd 7 : 4.0 s, how far do you travel during this inattentive pa dcof 5tuj-5a1 +7/j u()hhl:u7wnep4gp p iferiod?

  If you run a complete loop around an outdoor track (400 m), in 1s g9a:k5xwg5o cc(;wkhom;k4 00 s, your average velocik ok5wgm;( 5gk s :ocxa;94wchty is

  A polar bear starts at the North Pole. It c2la)sg en72/s 06d qbu/nlzs 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. l /z b 2uqd)sngsnc6/ sal7e02 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 4sj; jhind: 51gw cjhha )fh -bx5)5hu1.0 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:5g uj;fsh 4j51-hhx)d abj5hiwc)nh average velocity?

  You are driving home on a weeken wky)d7sa/ 4lzk( -lykxp 4e1qd 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 minutes. How far is your hometown lalk -7 /e)wyxyq(k1s4 z4kdpfrom school?

  A motorist travels 160 km at 80 km/h and jepm*u4nx6: j 160 km at 100 km/h. What is the average speed of the m* :um penjjx46otorist for this trip?

  A motorist travels for 3.0 h at 80 km/h an2bz5m1 qgc f1ed 2.0 h at 100 km/h. What is her averagf mgb1215qze ce speed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 25v8lw:8nglpwmtv 79jy ,s 7ob(4rh8 it 0 mi/h north for 750 miles. What is the averageo 7 7:8wn8vmr9gs,vhj4(t yltb p8w li speed for the trip?

  In a 400-m relay race the anch)yjsz v s cwk4ukyy: m*alp3-/u*g:1a orman (the person 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. ls-vma3zkwuupj*y k :/ac*:)4 y 1ygsWhat 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 c j2mynzvob- (c/0k(cg ar's average velocity during deceleration was 75 km/h. What was the car's decc2gzbv/o(jyc0k n-m( eleration while slowing down?

  An airplane increasesw3 ;rik uu4f, a;ewo(dgosc4* 1yoly3 its speed from 100 m/s to 160 m/s, at the average rate of ed cowkyu gy*4;riofso3 ul;13 (,a 4w$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accele2xvs.6viu3co + ggt7 yrates 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 acceleratesqmab5:4q 0mfa *a23s x,igft-)ejd cu 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 txe)+zln; n0:tgf +cbg,tfk :speeds up with a constant acceleratiolgn,;g+f)tf zx ck+ 0e:tnt :bn 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 7.3 m/s experiences a constant a*p9m;-i 4p.fitb ,bw yb xz1mlfvl8;vcceleration oy,bp l vm 1b*fxmb8v;t wi;.zi4 fl-p9f $2.2 \; m/s^2$. What is the cart's displacement during the first 8.4 s of its motion?

  A bullet moving horizontally to tajurcic r:wq9:(y 7p *p:izm q /xqi50he right (+x direction) with a speed of 438 m/s strikes a sandbag and penetrates a distance m qx7rpujii/ wq:aq5(y9p0:z : *ricc of 90.63 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult r,via2t8ech8yg 6 x4 yon an aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this reiy4x,e2vrg y6 8hc8taquires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant accelerati pc3qx3xzu+wbgm 2u+(on 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. Whato6m-3 z)tyk tj is its average acceleration?k6) m3-t yzjot

  An object starts from rest and undergoes uniform acceleration,gm4558fgke0eehjtm ex63a d . During the first second it travels 8.9 m. How far will it travel during the thir edeg me5jhkxe3fa,m4 t80 6g5d second?

  An object is moving in a straight line with conszfx+3n(x 9y/j zfr/fl tant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is travel 3fynzff+9 /x jl(rzx/ing at 10 m/s. How far does it move during this time?

  A car starts from rest z-9e+lcgz .kvs / glkrrv m+2x aj:g65i,tk)xand accelerates 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 roadbt;ar tj4h5strm : u3-a4( nft 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 ld enxgnnu4rwg ;3sgo s,5)2 ,eight turns green, a car that has been waiting at the intersect,3 )unegw ;gs g xno5ren,24dsion starts 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 spe/t8 espzffx1;2 fddm) ed of 12 m/s on the surface of planet X where the accelerpff)x /;2e td 1sdmf8zation 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 opox15 p*)p 9nb h+zqzjf 12 m/s on the surface of planet X where t1pp 5h po9b+jx*qz z)nhe acceleration 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 n dyy5uwg)r10a speed of 15 m/s on the surface of planet X wherngrdu5 )10yyw e the 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 on the surface of planet X when2 8tiws37 *va,zlubyk +lc7r re the acceleration l ,i7w83n vkct zbslyu+a*27rdue 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 yuvcm(:v fd(;tour friend holds a ruler between your fingers and releases it without warning, how fvm( ;( v:uftdcar can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. Wxm2(7 vqgawqw7h /-vpz4 io/: eos/ j8buo0fshat is its velocity after 3.00 4sq/spmf8-/wuxg( ob o vqj/2w h:v0 7i oez7as?

  A bullet shot straight up returns to its starting point inf uwsp88y*q di ff5/yy7p; .st 11 s. What is the initial speedy ps /ywf*ftqd;s8p 7f 8.yui5 of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does ita(jp b;)0zphrjt)fvdm8f4i 9 take to r;)m zihjbd9)4 ffrp0j a(tv p8eturn to its starting point?

  A ball is thrown downward from the top of a building with an initiq kmfk 1hw;s;y sh oux0)83,mjal speed of 14 m/s. It strikes the ground after 2.5 s. How ;shh)yqm sj m k0k3ox1;f8u,w high is the building?

  A ball is thrown straight up wi8ksukoe0 h97rsn((hk th a speed of 30 m/s. (only fill in numerical value in the bla( ksr(s0h hkk8e9u 7onnks)
(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 a speed of 32.0 m/s. (z(smr:v q zj ) en.)n8)pw2wfxuse $g=10 \; m/s^2$, 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 14 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 14.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the v8g,b o+ nndt1felocity at t = 1.0 s?

  In Fig. below, what is the vmtgyze:e2l66be z :*4w xlt5relocity at t = 2.5 s?

  In Fig. below, what is 9 zqf,t/q j0 n+a/dyy2c0 rv9en bcwg)the velocity at t = 4.0 s?

  In Fig. below, what is the velocity v8 4 1xpnd,igbu/w3f5 ckfr8u at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to 40 dyz+7 xuxoe*.0 s?

  In Fig. below, what is the ave9u h8 iuu5vy*jrage velocity from 0 to 6.0 s?

  In Fig. below, what is the acc;1ae 1bomali, b(lrt (eleration at 1.0 s?

  In Fig. below, what is thepnu/j20sz7wg/7g a8* md 1kok qag+yn acceleration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 ty69wg3 ; 2g(dv5eq4thali uz jo 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.1xl,swf3r z m)0 s?

  In Fig. below, what is the displacement from 0 to 8 n,mcs3tlux 9+.0 s?

Does a car speedometer measuipo uh.3 mkxy),asf2p) +zt4vre speed, velocity? {speed|velocity}

  An object can have a varying speed if its velocity is constant.oiwvku 6 s:9shd* eb1,)okwegq3o i2(

  The velocity of an object can be negative when its acceleration is positivwj3fi2l s; +1wcj-n+z(n ba o 3lkrao9e.

  If one object has a greater speed than a second o)ngey*p s,9 mgdo, v4sc4ei7h bject, the first must have a greatepsee7hg4 )4,so*gimc d n,vy9 r acceleration.

  Two cars emerge side by side from a tunnel. Car A is travel4)b8 b6z l-v)bcmci -s2gibn gj1 r6raing 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 dz-nn98m ky0 bd6dl-adu + i5muk6h +vittsg 99ecreases.

  A baseball player hits a foul ball straight up into the pt;tgy(i84ev air. It leaves the bat with a (;peyvi g8t4 tspeed 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 objecdlj6n. mirw16 t speeds up, what is happening to its acceleration, how does it change if air friction is ignorenidj 61rm 6wl.d?

  As a freely falling object speeds up,tifv +2o,(ffk2tn, y(1nxwql n(q ku8 what is happening to its acceleration, how does it change if air friction CAN NOT be t1, (( l2u f2qvk8n qfni, +tkwnf(xyoignored?

  An object that is thrown vertically upward will return to its original posi7wq1j fkorz0t4;6 :bb bg oe6emhx;g5tion with the same speed as it had initia;o7m5wg 0qhojb: x ;b1g6trke46f bezlly if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero veloci+kecp yef8931/eznhj0ygqkbyp 4 0+r ty and nonzero acceleration at the same time.

  An object can have nonzel t -k4rrzx;;kro velocity and zero acceleration at the same time.

  An elevator moving from the second floor tozrfhf. /eb:k8z-coy7 kda3 tg: 7t7cl the fifth floor making no stops along the way has zero acceleration al:bfr fz g877ekzyc/catlhk.-3 od:7t l the time.

  A rolling ball moves from w*mzo0+ex(3 dbfs qgzqzw0+) $x_1=1.7 \mathrm{~cm}$ to $x_2=-7.4 \mathrm{~cm}$ 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 $t_1=-3.8 \mathrm{~s}$ is at $x_1=2.2 \mathrm{~cm}$ and at $t_2=4.3 \mathrm{~s}$ is at $x_2=8.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps k trsb5kl5tfa(jq/i 44i. ux/ around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.5 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its traine 4 hzj.kac:saq-*:wlzr in a straight line, moving 103 m away in 11.9 s. It then turns abruptly and gallops halfway bac al:cjszh z*q-.k w:4ak 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 from 3melgo8 v/c,8q ua;qr$13 \; m/s$ to $23 \; m/s$ in 4.5 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 g ;1e;kptfxb:mvbo ;+ h ,x*m.4komnu$21 \; m/s$ to rest in a distance of 60 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed of n25gg n.48bjtru:qd h $28 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.6 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter yb(pjm vlr72dbb v12b5h-y6zb 4k7f ccan burst out of the blocks to essentially top speed abouz1 rf72 v-5vby2lbkm4y d 7b6jhc(pbbt $10.4 \; m/s$ in the first 12.6 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 h dl,iuu2os/o681s gw from a speed of $20 \; m/s$ to rest in 4.19 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car n85kx hijcz0k.u/ 0l dow(dx5 leaves skid marks 92 m long on the highway. Assuming a decelerati kc wdn8k.( u z5xoxi0dj50/lhon of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$