Suppose that an object travels from one point in space to anh:t o83bvi/uy other. Make a comparison between the displacement and theth yu:/b3voi 8 distance traveled.

  When is the average velocity of an object equal to the instantaneous velocnvq( 8) ddy3i6v tib4z/p3f jrity?

  A new car manufacturer advertises that their cna64o)6 tx sbpbdt 8;yxqn, e3ar can go "from zero to sixty in 8 s". This is a descriptio6nt6) qsd4p xb8 3ytb a,n;xeon of

  An object moving in the +x axis experiences an accj::y umvymw d7o-w nw*8o-7hseleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to th xcmqa713l zk po/z;vb3:a,mb e East (+x direction) begins to slow down as it approa7k/ox qavml:1az;3 zbc,3bpmches a traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow down as ic .d)lvn tq1rltogg/4 eh-l aovak , 5+f)-)jot approaches a traffic light. Make a statement concerning its accelera) dqt,l a5 4)l+re)o tac--kjfv1voho nlg/. gtion.

  Suppose that an object is moving with a constant velocity. Make a statementj8cjzqy q9ua;:-h) wb concerning its accelhq;)jwjcab: -8yzu q9eration.

  If the velocity of an object is zero, d7i -c f36izg9pbnch)o8ec8vd oes it mean that the acceleration is zero) d o38-pfi9vbgh ce cni7z6c8? Support your answer with an example.

  Can an object's velocity change dnz)2xa/1svqz 0 x2+9xmypz o jirection when its acceleration is constant? Support your answer with a ovsn2 1/ax)myz xx+zp q2zj09n example.

  Suppose that an object is moving with e e cgfe7m5l5z0,ojj- constant acceleration. Make a statement conceeeg fecz5m 5o0,jj 7-lrning its motion with respect to time.

  Can an object have increasing speed while 2+ 7dw) d8zaqr qg3rtrits acceleration is decreasing? Support your answer with an exampler7 8tzq)rd2w+ gqd3a r.

  Suppose a can, after an initial kick, moves up along alzaq ofw;-b8c)1s-c x smooth hill of ice. Make a statement concerning 8szxqwfl-1 ;cca)o-b its acceleration.

  Under what condition is average velocity equal to the average of the object (gwj zc-7k:t v 5-hai)rzaah;'s initji vw agh z)5;(r tkc7h-aa:z-ial and final velocity?

  Objects A and B both start at rest. They b2pse f69fd noa,xmp+2soe mp w9ro ;*7oth accelerate at the same rate. However, object A acceleswf 2;os9re2px+mf*9enpo76 , admpo rates 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. They both accelerate at the same rate. H*fgz;bb*oojh k10 ep( oweph k(gzeboo f*1*; j0bver, object A accelerates for twice 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 friction, wc))xws zbc*6d hich of the following is true concerning )s)wz*c6xdcb its motion?

  When an object is released from rest and falls in no nb(06g 9 ).fb9 9i ophu3fjjown/nfthe absence of friction, which of the follown.9)b0fnu h f oioj oj nwnb693(/f9gping is true concerning its motion?

  Suppose a ball is thrown straight up. Make a st:mu q)nsa/f2ce:8vvanh)k2iw xz2m .zh 0pj6atement about the velocity and the acceleration when the ball reachnmhm2i/hz6sa eu:q80)k v nf 2j pa )2cvx.:wzes the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just be lqd 3e t++0bj61q3pbq2 tghkffore it reaches its higb102+dq qg+bf j3kteptl 3q6 hhest point?

  Suppose a ball is thrown straight up, reaches a ma24z0m5ozc3ca mspa 3yximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is goi3c m 2 p5a4csz0oyaz3mng up.

  A ball is thrown straight up, reaches a maximum height, then falls ea0kc34( p sjzz.nkn8 n.m0kl to its initial height. Make a statemenz p 4zkan.lnkns0.j3 e k0(cm8t about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downptms -1b sn6/qf54yljward in the absence of air resistance. Make a statement/m f-plqtsynj1456bs concerning its acceleration.

  Suppose a skydiver jumps from a high-flj rcamqhk0; z o2m*4co:jbq (5ny1wr:ying plane. What is her acceleration when she she reaches terminal v14b2joc0: co rz ;j ya*mqwr:5mk(nhqelocity?

  A ball is thrown vertically upward with a szc0c7+rlq:v1 f at5d 8ks9lwtpeed 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 b k7va+80zq 51ct: w9trldfl csall go than the first ball?)

  Ball A is dropped from the top of a building. On37vpwy ie6k;re second later, ball B is dropped from the same building. As time progresses, the distance betw ip y;e7r3vk6ween them

  Ball A is dropped from the top of a building. One second latert ;o mooa)(namy( 5a:v, ball B is dropped from the same building. As time progresses, the5; ay)v(tm(oa: noao m difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, and 3+n fa+tko-uqmg*bb.the other is thrown down, both with the same initial speed. What are their nku bf-tm* b+.g3q+ aospeeds when they hit the street?

  A brick is dropped from the top of a building. A ; il wifn)+kr3 n jp0,otn(c/asecond brick is thrown straight down from the same building. Thi;r an j+,nif/3ok nwt 0)p(lcey 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 /bcjb r a4c*abbj,6b*bdz2 62v r/nx: ;wy kuythe +x axis. The position versus time graph obb2war b/ny bj*6*v/ub ja 6;x:,cd24k y zrbcf this object is

  An object is moving with constant non-zero acceleration in norc66 p0zmj7x7p *za /ist2 8 ywuiz0yvty5:the +x axis. The position verspi:smp6z zia5u 7oy/nx08 2 tvcyjtz0* rwy 67us time graph of this object is

  An object is moving with constant non-zero velocsq;s. *,sh( eeznj3aaity in the +x axis. The velocity versus time grap,ss; .jaqs(eae nh3*z h of this object is

  An object is moving w7qa0;7vb p rqbith constant non-zero acceleration in the +x axis. The velocity versus time graph of this object b7r07 qvbap; qis

  The slope of a position versus t rcov 1: qhwu-f,d4ds,ime graph gives

  The slope of a velocity versus time gqlr - duum.24jraph gives

  The area under a curve in an accelerjhaii r) xb(-mxb(9 tb. 3tr)oation versus time graph gives

  The area under a curve in a velocit 2va7zs5,lkyu y versus time graph gives

  If the position versus ti1bgs sh1 80stqme graph of an object is a horizontal line, the object qbgst18s1s h0is

  If the position versus time graph of an obje6 n6xhi gzn(0gu o.p/ect is a vertical line, the object isen .nuzi/gg 6 6h0p(xo

  If the velocity versus time graph of an object is a krfr e +nuid .2rq(.m:(t;gmshorizontal line, the object ifm..t: ( nrk+2sg rirqu( ;mdes

  If the velocity versus time g ez4cjh t+,xl(raph of an object is a straight line making an angle of 30 degrhe c ,+tlzj4x(ees with the time axis, the object is

  An object moves 15.0 m nortrkrr,-k91wia k u.bi5 h and then 11.0 m south. Find both the distance traveleiuwrb,kr r .k9-1ak i5d and the magnitude of the displacement vector.

  A boat can move at 30 km/fps/gw f uord+1 ru7 y n().5zffuae)6s6(hsjh in still water. How long will it take to move 12 km upstream )6z o75 urpsf.)nr 1gswu+da/j ff( u hf(6yesin a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = ,ygep9xppr hd0 yrtucjc9*p6w4 ly92-vy-7v 1609 m)

  What must be your average speed in order to travel 30sln/uqxk0 b(cx ok**50 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 ho4ka7 j 0dd73h.4q8 s n:szqby44lhzzmm0vkw surs and 57 min. What is the average speed of the runner in m47 b:ky4 dmz hzqkahvsn3qds07 4l04szwjm .8/s?

  A car travels 90 km/h. How long does it take for it to tramf0d/zq+m7fu )yr6b3ntn70.r ncx obvel 400 km?

  A ly (light year) is the disrz(o l4ffmly+ 2 stdg*nwx:6-tance that light travels in one year. The speed of lightgn:-o+d s2yzml4trf(6xfw*l 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 loo fhnwbd1n-ty s7ju6( 0k to the side for 4.0 s, how far do you travel during this inattentive t6-(u7 bnn 1djf0yhs wperiod?

  If you run a complete loop around an outdoor track (400 m), y,)h zxuc63uhxz) i; r.5wki bin 100 s, your average velocity)ixzy)r5huh ;3bwiu .k, c6xz is

  A polar bear starts at the North Pole. It travels 1.0 km south, then :vgmnx,;c( 7m0val eys gp31p1.0 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 mpl c,3sm(n;7g01vyg vae x :pthe bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, thencdg f9/4n-,ybqs s/j5 4djtpu 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 bear'pd -syjb4 tc q//n95j4 ,udgfss average velocity?

  You are driving home on a weekend frjs lb;fh72nktf nw-+e85e2o hom school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mie22hk7whl+;etn8s oj5n b f-f/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/oj231vqtg9kiyd k*,fvw9 wm( m 77j elh and 160 km at 100 km/h. What is the average spetm 97w9dvj ,fw1v3k m*lqiy j27 k(ogeed of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is hb(rs /g3k)mbcx i )+toer average sp)+o3cmsbg() bx/rtk ieed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 20qgpjq ,;:ka24w5qvo zzxq m,gk3u: p pt(p8q50 mi/h north for 750 miles. What is the average speed for thepq 4oxqaq8 g kz(:ppv; p5k :,,tqq02zj3wgum trip?

  In a 400-m relay race tx97xsr:l e vu)he anchorman (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 is the largest lead the team B runner can have when x7xe9rluvs) : 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 14 szzip cdgjf k f7dn 1rr9*.:v+,. The car's average velocity during deceleration was 52 km/h. What was the car's deceleration whilep9d * :rf v,d+z jkf.1c7nrigz slowing down?

  An airplane increases its 46lpe7*6aumha/d m b)+gpkgh speed from 100 m/s to 160 m/s, at the average rate of a7p*e+6udl/km6 ) hg4 hmbpag $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates 0clwvq// 9uq zat 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 acce;ltr 7ks(ro8/ ; mkyrelerates 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 bfdalf,su7wu :*chenc x 8)75with a constant acceleration of uws 7d*ex,c:c n8fu ha)f 57bl$2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 1.3 m/ta(bk l 3ok*9ns experiences a constant acceleration o*oka93n(kbl t f $2.7 \; m/s^2$. What is the cart's displacement during the first 7.7 s of its motion?

  A bullet moving horizontally to the right (+x ba h:az0* 5s5g*zucszp ,loi: direction) with a speed of 205 m/s strikes a sandbag and penetrates a distance of 51.00 l, i:sazsoza 5*b z*0u:5gchpcm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult ontwm:t, l10gqf an aircraft carrier. It reaches a speed of 42 m/q:wftm tgl1 ,0s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest move20o zscf:hy t wlvx15;s with constant acceleration 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 itsu5 yaa6l b kvsn0hb 9/a*4t.ki:/jxr g average accb/ hux94a i6/nkts:j abygal*0r v.k5 eleration?

  An object starts from rest and undergoes uniform acceleration. During the f jvefj5-655zelad l, rirst second it travels 2.5 m. How far will it travel durv6jzelr55 - fdl,j ea5ing the third second?

  An object is moving in a straight line with constant acceleration. Initvexmn;u 60i2(nv8ufugv qsqa.jc9 1,ially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this s qg 0n6 vn1(uia92xj;vue.cqv f8mu,time?

  A car starts from red;nxp3z+j-g0unji 8 y st and 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 ei095sr e 39ft,ki hu(oyts;j 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 thagx b2 loifo(pu4:.z+p t has been waiting at the intersection starts ahead with a constan2o.(4 :opbl+zpx igfut 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 uptn3lditwsh .)g .a(x6/-mg y8nrx4g dward with a speed of 12 m/s on the surface of planet X where the acceleration due tottg) m(ywga/6.hr -ddnxi nl8.sg3x 4 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 n)d,zmt6 bclu+4t/bi the surface of planet X where the acceleration due tnttzub4i)+ bl,6dcm /o 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 of 15 m/s on the surfaqn9;:gsy -l-bix - hdzb(/cmdce of planet X where the accelerat ;inb-:(gbm / hyc-9xddz-sqlion 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 5) 7 dvltm(z7mnqq6hasurface of planet X where the acceler( n mv6h7qa5l)tz7md qation 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. If youhyejwoq 83xn8 f.6so0 t5g*zxr friend holds a ruler between your fingers and releases it without warning, how far can you expect the rule3 .fo50sqt y xhnxge*68wz jo8r to fall before you catch it?

  A ball is thrown upward at a velocity 3qmd/mxb u-g)of 19.6 m/s. What is its velocity after 3/)g dm3m-bxuq .00 s?

  A bullet shot straightp3hr.bboc;d k7o, 4 zr up returns to its starting point in 14 s. What is the initial speed of the bullet ,b hk7r4c3p; bzo.odr?

  A ball is thrown straight up with a speed of 36.0 map1-4qsb. sgnor,wy//s. How long does it take to return to .14wsp q-bn ogsa/yr,its starting point?

  A ball is thrown downward from the top of a building with an insgp+l6du,216go j;sf f dwmy( itial speed of 22 m/s. It strikes the ground after 6.3 s. How high is the building?w;6+o6sl1mgy2 jsf(pfug,d d

  A ball is thrown straight up wi )gbmmyo mkkul..*f,9 th a speed of 30 m/s. (only fill in numerical value in t gkk,mlb*uo..mf 9)ymhe 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 with a spee7(y4-fj s .cjeqrjdr 2d of 45.2 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 1 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 10 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 10.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocip)p2mtzdh.:1 mt 12;gl cnv fqty at t = 1.0 s?

  In Fig. below, what is the velocity at t = 2l h8c-6ykedad7 f g*3c.5 s?

  In Fig. below, what is the velocityq+v )m6 ,m3 kjoirmby ,4jlt gb48,lje at t = 4.0 s?

  In Fig. below, what bu8 x0wk 3b(gdis the velocity at t = 5.5 s?

  In Fig. below, what is the a+ o w)ya3f(g ir5vawc9verage velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity fr9mi +ch8c6zs kom 0 to 6.0 s?

  In Fig. below, what is the accjkr.xxy/ ( -:1g.yqk yqab,jneleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 s5)/ +ad.m lcebo8g g1z njoi;x?

  In Fig. below, what is the average acceler;j9m 60h- ito w hm9kbo;5tjtpation from 0 to 5.0 s?

  In Fig. below, what is a kz(3z/ y;/il yxclz5the average acceleration from 0 to 8.0 s?

  In Fig. below, what 8)zjsh ksl+v4is the displacement from 0 to 8.0 s?

Does a car speedometer measure speed, ver7ji,kx 1zc7d , 9b 2ebaqlo(blocity? {speed|velocity}

  An object can have a varyingi k65 u0eazr*i speed if its velocity is constant.

  The velocity of an objec//tn, danylio /8 (hsyt*e-tu t can be negative when its acceleration is positive.

  If one object has a greater an n;v.mr) covno*5w 0speed than a second object, the first must have a greater accelerati .om rw0n5vc)n;*onvaon.

  Two cars emerge side by side froma frwxs03 )k (zrf85ji 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 decreasesepjljym+d*2rt/-9)1 urkmgnlhf a. 8.

  A baseball player hits a foul ball straight up into the a s5 -sf8/rndjxfo aqi(dvx 1r 8:91npnir. It leaves the bat with a speed 9f d:n81fsx- rsqd 1 jxo(/ rp8anni5vof $120 \; km/h$. 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 acceler6o;4 ym:nz)au usmiy 4ation, how does it change if air frictioz44 i soa;)n: 6ummuyyn is ignored?

  As a freely falling object speeds u ))wmull9h hftu m1x -za:a))pp, what is happening to its acceleration, howhlau-1 xm)zt:u )pw)fah9l) m does it change if air friction CAN NOT be ignored?

  An object that is thrown vertically upward will return to its original positiogqq+ r2ex x3;vn with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how willv+qexr;3g qx 2 this result be altered?

  An object can have zero veloc5q s5pa hp/ oai,hw8(sity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at the samiz .u42o:njg ye time.

  An elevator moving from the second floor to the fifth floor makikq.ey,( /lrscsocn7l (o12w o ng no stops along the way has zero acceleration all the time2 /1c(nqls rlsow 7yec.o(k, o.

  A rolling ball moves fr929v: isg 9cty htzkgw)9; cnzom $x_1=3.0 \mathrm{~cm}$ to $x_2=-8.1 \mathrm{~cm}$ during the time from $t_1=0.9 \mathrm{~s}$ to $t_2=5.9 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.4 \mathrm{~s}$ is at $x_1=2.3 \mathrm{~cm}$ and at $t_2=3.3 \mathrm{~s}$ is at $x_2=7.7 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight com fqh)3-b1xb g zm*c8vjplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.4 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 96 m ao kyi55/ fh.txqnmxzo-8,9ojway in 8.5 s. It then turns aoz8 /-5,y t xxq5o9mnji.hfkobruptly and gallops 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 from / y+ va-lcrji37n9yey$10 \; m/s$ to $25 \; m/s$ in 4.6 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 tk9 .t* khz5uk$17 \; m/s$ to rest in a distance of 60 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reachz2pafh..d oik;qfm4dk4i5f bc)r 6c) a speed of $31 \; m/s$ 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 can burst out of the blocks to essentially top speed abo actacl4woeoqsp51e1lt 2e i0-ni qp/ c+*a5(uai5p es1cpe c*5-0ow2/tq ae( t 4lo+1qilnc at $11.0 \; m/s$ in the first 11.4 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 speed of n0qcmon6a;8f 5lqw6 2yabv5*bp- slk $21 \; m/s$ to rest in 4.75 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. Asyvfsj.l+di2xb-,n01d .ot9v ,v oez ksuming a deceleration ndvoil0z-1 ,.kyd+ejsxvv9.2,tfboof $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goieghc 7g a55enug4*ee*ng $25 \; m/s$ 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. A8 tw7 el44 d.,v viv9aqr;qz*j.pha arfter exactly 27.0 min, there areavl. ivd4e8q,t4r 7;vwaja9ph q *.zr 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?    $s$