Suppose that an object travels from one point in space to another. dxk9 ;y 7t o( 27s(agnyeflb)xMake a compabalxx 7s7)g9;nfo kd(2ey( tyrison between the displacement and the distance traveled.

  When is the average velocity of an object equallfe kezk2e -*8 to the instantaneous velocity?

  A new car manufacturer advertises that tgs9k lv, vpqr 0zvmkh/ 0/gd**xjgo.3heir car can go "from zero to sixty in 8 s"3q*j*vzsgg. dov/k0 vkh mgl /09,xrp . This is a description of

  An object moving in the +x axis experi*+;k e4e 4agorjm-p ojences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x dir )rixl;d97mqms)oge8 ection) begins to slow down as it approaches a traffic light. Make a statement concerning ig8oe mx9l))dmqs 7i ;rts acceleration.

  Suppose that a car traveling to the West (-x dirm 3v9imd z2eu2ssto*+ ection) begins to slow down as it approaches a traffic light. Make tive*2+3mm9 u2zs osda statement concerning its acceleration.

  Suppose that an object is 35kxk mw/ r6rbmoving with a constant velocity. Make a statement concerning its accelerationrkb5 63m/kx wr.

  If the velocity of an object is zero, does it mean that the accelctk + jidhj57k oy250reration is zero? 5tc5ijjyr k d+ho70 k2Support your answer with an example.

  Can an object's velocity chany v; -f0q) :rk do ,uhneyvp7(ind1.mtge direction when its acceleration is constant? Support your answe v1re(,0o yip: d.v; -q7)tdhnufy kmnr with an example.

  Suppose that an object is moving with constant acceleratiop7raa2g ) iw,hn. Make a statement concerningw,a irh )a27pg its motion with respect to time.

  Can an object have increasing speed while its acce0dk a;xn q*2wbleration is decreasing? Support your answer with an ebq0xwnk;* 2 adxample.

  Suppose a can, after an initial kick, mxa4h i,a/kuuv,mld dm3)-3v doves up along a smooth hill of ice. Make a statement concerning its accmmvd ku id4-xvh)33,,luda/a eleration.

  Under what condition is average velocity equal to the average of the o epf2-3es3w 5anaxu0 zbject's initial and finxes -2upn5 3wa0 azef3al velocity?

  Objects A and B both start at rest. They both accelerate at the same rate. Ho.+c2d xyrlx ,kwever, object A accelerates for twice the time as object B. What is the final speed of object A compared td +.xl2 rxcky,o that of object B?

  Objects A and B both start from rest. They both accelerate at the same rbo)u p- j6( id8mxru-nqc ;gn*ate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared to that of i6 c;x)*d( --bnurpo 8juqgmn object B?

  When an object is repc u*jr8t1ls/0e4 byb leased from rest and falls in the absence of friction, which of the followincbtby1s8r p*jlu/04eg is true concerning its motion?

  When an object is released froegajcz3zg:, mmy0 d8tf 8yz25ok 1)agm rest and falls in the absence of friction, which of the followinzo:dzy m)z gm23g18,fate c 5agy8kj0g is true concerning its motion?

  Suppose a ball is thrown straight up. Mawxcw6)zb p,7 oq: hmr.uo92h(b o7vih ke a statement about the velocity and the acceleration when the bwb 6o,pi(2o7hw x9bhc m r:vu7 .)qohzall reaches the highest point.

  Suppose a ball is thrown straight up. What is its accelerat:jyzffu;4 hw p(;6qj mion just before it reaches its highest :m; (w6q;pf4jfyh jzu point?

  Suppose a ball is thrown straight v0 m7b(y vw1l36vqvb iup, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the vbw 3 17v (0q6vbmvvilyelocity and acceleration as the ball is going up.

  A ball is thrown straight up, reachp.+ ;g* kectfvh;am7i es a maximum height, then falls to its initial height. Make a statementcp*gm+e; .av; fhk7t i 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 rewgxh0z 1,1. m 3cjkfoca .npo4sistance. Make a statement concerning its acceler,x n1cckz4mj3 fp.hgaw o0 o.1ation.

  Suppose a skydiver jumps from a high-flying plane. What is her un3 iht+pd q)/m;w/n jacceleration when she she reaches terminal velocity?+thpwiq3 u/;)dm jnn/

  A ball is thrown verticalweo x7g9q vn;sr*leydw6/ +(y ly upward with a speed 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 frl*w+d7nx(6ee y y;vw/ goq9sirst 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 ia j/1esv1*t1j8 tdjn+ n htb/rs dropped from the same building. As time progre+1h aj* rtj/dvne1/8nbt ts j1sses, the distance between them

  Ball A is dropped from the top of a building. One second later, ba3trv7g (omj,;vvtitf0y;. f) t3 pypkll B is dropp vp;t f7)oy(30 tkv.i;tmr,pvyg j3tf ed from the same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, 029 gchzob8muand the other is thrown down, both with the same initial speed. What are their speeh8 m cg2ob9u0zds when they hit the street?

  A brick is dropped from the top of a buildinzl+ y(9a6q2 o t9kiaajljnf 1 4omm+2pg. A second brick is thrown straight down from the same building. They are released at the same time. Neglecz lj( a9n 2aa9fl q6iykto4 j2pm+m1+ot air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant no:wdi h ;.os9dvn-zero velocity in the +x axis. The position versus time gw: v9dsi ho.;draph of this object is

  An object is moving with constant non-zero acceleration in theiwboc,q 2s+slk 2/a9 b +x axis. The position v9ciwob qs2+sba,kl/2 ersus time graph of this object is

  An object is moving with constant non-zero velocitqpn6r cv1v ,lm.f 4wua)n obpk-6e(no;we4p .y in the +x axis. The velocity versus time graph ofq, 1nb .fwv e46c4norpem6p-(lnao.)w upv ;k this object is

  An object is moving with constant non-zero a*mkcn7twf;75n b lnc -cceleration in the +x axis. The velocity versus time graph of this o;5-nfm7w nb *c7ln tkcbject is

  The slope of a position versus time graph0gy7cwp1pth 5j+n5 hh gives

  The slope of a velocutyvx5 waoj txj3* *11ity versus time graph gives

  The area under a curve in an accelelb4fiiigt- k y/5c(cv + 5f)bdration versus time graph gives

  The area under a curve ivogm 2d bmplkmd vs41b-)z010n a velocity versus time graph gives

  If the position versus 7cdcx6qh p;f)xuc p )/time graph of an object is a horizontal line, the object ihp) /;6f7xq c)cucdxp s

  If the position versus time graph of an object is a vertical line, the t.323vf6lx56 hl6im emxu d ijobject isx3 imju6itehf 32vd5.lml6 x6

  If the velocity versus time graph of an objecunef z)1 od90,ch3ns.f c xwn4 aom +o(odvv+*t is a horizontal line, the object sfvvaz,.9 oe3n hnmoo(+ * wn dc14udx0)+focis

  If the velocity versus time z/u( o2xh6lbkn)l5uh m.nh1r graph of an object is a straight line making an angle ofkh1l l()muh5/nx2ub6 znr ho. 30 degrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both th)r 5tyi :)7xhyooa gp;e distance traveled and the magnitude of the displacement hyt:po7)i ; rag)xo5 yvector.

  A boat can move at 30 km/h in still water. How long will it take to ma+mre*ge3n0; h2 8u(ua,brtik f3cl66 ft ltmove 12 km upstream in a rc3n r*h ek02, g lfe+ m a6aibm8u;ttlr63(uftiver flowing 6.0 km/h?

  55 mi/h is how many m/s? (*5 *9shj+ez d53kpvxt)x defj1 mi = 1609 m)

  What must be your averag0e 5o 8a a+eru*bmxrty0cz .m8e speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately cv* 8yhcdp;7m 42.0 km) in 2 hours and 57 min. What is the ave*ch 8yd7cm;vp rage speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to trj 5wmofrn2*6ldn ou/3 avel 400 km?

  A ly (light year) is the distanhks)6ajaa /:4- z) xc b+6p+v b3ylftr t:jhnzce that light travels in one year. The speed of ll+n3/ ch)ryjxj) p a6hts za bkz:6a:fv+-4btight 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 4h-4ij f:yg6mhna5z 1:haxfd5.0 s, how far do you trav-5j6dm: h1 n:fx ihahzf 45ygael during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100qm g+3lo+-iq p s, your avera -lqo3m pq++igge velocity is

  A polar bear starts at the North Pole. It travelheb8 f zj74-hls 1.0 km south, then 1.0 km east, thenfhjh7- 8 lb4ez 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 average speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1teh a49(nsm )v.0 km east, then 1.0 km north, then 1.0 e sm (9ntvh4)akm west to return to its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weez.8pz x/se0iw kend from school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home ae/ w8szi.x zp0fter driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/v: ix+tj3dtsqu/6.bn h and 160 km at 100 km/h. What is the average speed of the motorist fij6 :sv3t xu/t .nb+dqor this trip?

  A motorist travels forv f) a*6 e:,s nczgc793jdr9vuhk gso6 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her average )6uofvkancegs9 hv3,6rz s79 :jdc*g speed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h nortoq fj12 fd57g1a 71mrsn7qfj th for 750 miles. Whatf7o2q 571f1s qj7 j1rmgft and is the average speed for the trip?

  In a 400-m relay race the anchorman7h5 bnoa-jatq0w05e+r 6d/rsnc6 vnq (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. What a-s wc/a+b7dver qn5ho06 jq5t0nr6n 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 7o *0 czxbc xp02 kgdool;v0q/12 s. The car's average velocity during deceleration was 51 km/h. What was p0 b/c dovqzcox 72;0* 0gkolxthe car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average rate ofamizb5u( oqcxfk, 6nz a0 34+d 3ab(z45x k na0 ozfidq+uc ,m6$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/bwj ly (xj(gq+s4 /x7gh 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 and accvnz6 egsi:e7qxg/1/w po* uq2elerates 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 conskrk(yxil d*p*h *ko,5, r4p9sz e k(kftant acceleration of z*sk,5 f o hk4*,ikkpr(*kx9l ryp( de$2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 7.6 m/s f +dsx5dr2**lqaw k4z experiences a constant acceleration ok4w2sd 5 qrd+ **xlfazf $2.4 \; m/s^2$. What is the cart's displacement during the first 8.3 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of 302j0-hc5 wgx(yb m/s strikes a sandbag and pene-gy 5w0c xjbh(trates a distance of 91.26 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft cavyr( rar5npx- n*:jf0rrier. It reaches a speed of 42 m/s at the end of the catapult, and -r0*xvj ( pn5nyrfar: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 acceleration88 u iqs7zmy* 7rnpwqary1+1f 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 dista vpjh1gg f21) h9jw:cwnce of 200 m. What is its average accelerav)c91g:fhp j1hgwwj2 tion?

  An object starts from rest and undergoes uniform acceleration. During the firq(, xruuxe ;9izgo* -yst second it travels 7.3 m. How fa*y;- ,g qrxoeu ziux9(r will it travel during the third second?

  An object is moving in a straight 6r3 (hbh r//qrm jc8elline with constant acceleration. Initially it is traveling at 16 m/6hc/br(rj /elr 3mq8h 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 accel8bbpmvw,y1 s;i7h da- erates 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 road can decelerate at ab fchogb vr3t,; aq9;p8out $5.0 \; m/s^2$ 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 at thely6 cu ;qo9-wradv .b.*eq ve6 inteev-e rq. b.uc *l 9;qwyd6o6varsection 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 upw wbin4docr m4-x.v:t 5ard with a speed of 12 m/s on the surface of planet X where the acceleration due t4 4rivtnw5:dm ob.-cxo 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 planet X tx9*mx + v2kwdwhere t txkd2+*9mvxw he 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 wi2dlcs.c5qq /nj. 3l 2wp;syiv q 7qkehi o26)kth a speed of 15 m/s on the surface of planet X where the acceleration due to gravity is22h cl5 s i;6qv2ij.e)7sqnw/k.3l q dyqp cok $2.5 \; m/s^2$. 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 surfacer lk5; d p13op8u kqc4)d4bdud of planet X where the acceleration due to gravit c upkdo)8 ulp4dqr 435ddk;1by 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 hold7b10vy 3wew;2prf dy4ph1mlzxq.x6 c s a ruler between yo4prlpmeydx1bw3 f1;wcv7xq2hz. 06yur fingers and releases it without 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. -/ pjmjwlokb gh( xw)sgpy pg,ad64 +2 e8;pf;What is its velocity after 3.00 h 26dpwxwea)p;s(fk pgym,4g o;8pl/b j+ gj-s?

  A bullet shot straight up returns to its starting v0*a d6-iqy4gernmr- point in 11 s. What is the initial speed of the bu4igmn d*6-- e 0rqryavllet?

  A ball is thrown straight up with v rnbth +l s+w8jo+s9gl x.j8(a speed of 36.0 m/s. How long does it take to return to l+lr8t x jwgho+b+.j 8 sn(sv9its starting point?

  A ball is thrown downward from the top of a builfkdfp,xrh2 k( k ;8lt.ding with an initial speed of 23 ( 2.lf h8tk ;fkpr,dxkm/s. It strikes the ground after 4.8 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. jz z vf- p;9:nvdmh9pk256odalp -l)x(only fill in numerical value in the blank xa6okfzl-92jvv 9-l) :pdmn5zd h p;ps)
(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 wit yijru )ohi-(8h a speed of 38.0 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 8 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 8.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the q;5// w/ icpvlq-cyw hvelocity at t = 1.0 s?

  In Fig. below, what is the veloce 76osq2w*f clity at t = 2.5 s?

  In Fig. below, what is the velocity a+, nzug,upkk d53n (xwt t = 4.0 s?

  In Fig. below, what is the velocity at t = ./g ;daoj5:eqa;p yqn5.5 s?

  In Fig. below, what is the average velocity from ynq 4h,ukz:d7 0 to 4.0 s?

  In Fig. below, what is the averagezd h;av)e3* im velocity from 0 to 6.0 s?

  In Fig. below, what is the acceler v lnb;y:ztm6 zba/88fation at 1.0 s?

  In Fig. below, what is the na:oye,ik 4l2 y)qt 8gacceleration at 3.0 s?

  In Fig. below, what is the average acceletae5t 6 4arugyd0h;d43vi2 psration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 t y xfxua uands/g,8mcb*k)d6,6x7q4 f o 8.0 s?

  In Fig. below, what is the diij)07adh (;n xkbmftdy+)+ xq kq-p f6splacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|veloc-s 9r ky(mo-kn6+ tif. rngl8aity}

  An object can have a varying spee:vrw4 z:f2lmpzyw/ 03z wo2wsd if its velocity is constant.

  The velocity of an object cyl -: j9hwilxd+2mt.jan be negative when its acceleration is positive.

  If one object has a greater spgt8.p xb4ifro a 9xn;/eed than a second object, the first must have a greater accelera.xa4ox/r; b tfpgi n98tion.

  Two cars emerge side by side from a tunnelychc m3(5n6u q. 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 ea w:ea)is01hk;1pkh its acceleration decreases.

  A baseball player hits adlvx/)o q6hlunvi v5 8vw :b/jf;h;m: foul ball straight up into the air. It leaves the bat with a spowi 6; /f::lmqh5hu n;8)v/bvjdvx lveed 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 h fe7r/z+ofsuc b:d3: iappening to its acceleration, how does it:/rb de3isf:+fu7z c o change if air friction is ignored?

  As a freely falling objee asp:m( h)c,oy 32qu;8wd gdect speeds up, what is happening to its acceleration, how does it change if air friction CAN N8 ;e s:(dy) w 3g,2daphoqmuecOT be ignored?

  An object that is thrt.9 xc *nh;f2 25*m khihwvatwown vertically upward will return to its original position with th 9* hckma 2hhi.xt5wv*nft;w2e same speed as it had 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 vw. l7pek* ca*the same time.

  An object can have nonzero velocity and zero j yb+mn x2o5 a4ihf26qacceleration at the same time.

  An elevator moving fromi26q,i ikx k*s the second floor to the fifth floor making no stops alon i6qk x2is*,ikg the way has zero acceleration all the time.

  A rolling ball moves fro tdd + 5g7rvctfnnzr;l*fq3 1jvf.6tfi4r/2um $x_1=2.7 \mathrm{~cm}$ to $x_2=-5.6 \mathrm{~cm}$ during the time from $t_1=1.3 \mathrm{~s}$ 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 $t_1=-4.5 \mathrm{~s}$ is at $x_1=2.6 \mathrm{~cm}$ and at $t_2=3.8 \mathrm{~s}$ is at $x_2=7.9 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight c +zl p-3wvynmfg*b(4 aomplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 9.6 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 straip bjy+ a: , *wpp*(r.iwn1cshc5n mpb(ght line, moving 96 m away in 11.7 s. It then turns abruptly and gallops halfway back in 4.8 swcp(n i phsyp1p. m:j**bca5r(nw ,b+. 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 fro;qva4r*d y3+ y6qpae1mfz 1ykm $12 \; m/s$ to $23 \; m/s$ in 4.3 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 frox /+ j(ptapkk*m $19 \; m/s$ to rest in a distance of 61 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reac88u x*u bm9lr lvx5v//kwlp,hh a speed of $28 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.9 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter(qs:mkc(mga htogo 1 zkw)y e/o(7 )wpqr1)1v can burst out of the blocks to essentially top speed abou)coayp7 gtkz ) o:(q/ (em()1w1grwsov 1qkmht $10.3 \; m/s$ in the first 12.7 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 f, it 9ykmy:wph9x0x+yrom a speed of $19 \; m/s$ to rest in 5.03 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m a(ne hlme 1x 3d-7 :sbel ef: 4(2swokj5dk8djlong on the highway. Assuming a deceler8j 7(ee3 of-(x2:1wjke54nead lhs: bl kddsmation of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truc: iv9 g7l9 2e(umi0+usyvr5pmvqe*x wk 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 less than 30.0 min. After ej gz0q 67 4a.f7wo7 yyvkjge2nxactly 27.0 min, there are still 1100 ygg04qn7of 6 k .7yzj2jew7avm to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$