Suppose that an object travels from one point in space to anothe8/nlft*.pc (acs4nj;g6 nuef r. Make a comparison between the displacement and the pl4/ct8j f*a.ns6 c;en nu(gfdistance traveled.

  When is the average velo x+v .+.59-y oy g*udkajy:lpzmt0dhscity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "from zero z4xmp/ 5 ausx/to sixty in 8 s/sum p4xx a5/z". This is a description of

  An object moving in the +x axis exg49wzj;v)mu m9l mh0n periences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow down as i 16bdcv:k /ju;r9::gbkemojht approaches a traffic light. Make a stge : ukj9o:jmcvk6r:/ bh;1b datement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow dx- vjz20f epxq-x6w ,yown as it approaches a traffic light. Make a0x w p-v2exf,jyzqx- 6 statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statement*ix assf: hq.+ concerning its acceleratia:*if+qsh.s x on.

  If the velocity of an object is z+ 4*kkgbcb.b obqn pc8+ coc+8ero, does it mean that the acceleration is zero? Support your answer witbb o gp+b*+n8c b.+q4 c8ccokkh an example.

  Can an object's velocity change direction when its au46tw5oi(s,x v rm *hocceleration is constant? Support your answer with an exawvh6tos(5m4 * o xri,umple.

  Suppose that an object is movb8exw81ik9 ipl,fuca* 6m- gu ing with constant acceleration. Make a statement concerning its motion with respect c8i fl au916uix pk8* bm-,egwto time.

  Can an object have inczuz vou1 ;qi:agk;8tf +h+ nzd4jc) 0creasing speed while its acceleration is decreasing? Support youku)nca h:4j;z +u;zi18q0od fzg+ cvtr answer with an example.

  Suppose a can, after2lp,dbbxj2gb(n il0 8 an initial kick, moves up along a smooth hill of ice. Make a statement concerning its accelel b82j2lix( p0d,g bnbration.

  Under what condition is average velocity equal to f;r; q obak5-xthe average of the object's initial and final vel x f-kraqb5;o;ocity?

  Objects A and B both start at rest. They both accelerate at the same rate. gb pvmq5x5r6 2t y:zttl56,jc However, object A accelerates for twice the time as object B. What is the final speed of object A compar65v tgy txbrpc2qm55 lj:t,z 6ed to that of object B?

  Objects A and B both start from rest. They both accelerate at the same rate *th5gr7k7h :jit y-ve. However, object A accelerat5 *vt7-trikegh y:h 7jes 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 rcrrjr;mc 5; 2l5:mg kbest and falls in the absence of friction, which of the following is true concerning its motio2gjmrm; rkb;rccl:55 n?

  When an object is released frot4;1/onw ikq+rd 2s*uk 9*o8 cdmyqk. rq lgy1m rest and falls in the absence of friction, which of the following is true concerning its motcond*kk*qqrik2gusm lt/r1q o4+d.;91y yw 8ion?

  Suppose a ball is thrown sf ld4bsf)iwvl 3dapt.o2k *5,traight up. Make a statement about the velocity and the acceleration when the ball reaches the highest.vfaws 2li dtlpf3 o,b 45)d*k point.

  Suppose a ball is thrown straight upex5xy4 yl d2*zehlm , z9bds41. What is its acceleration just before it reaches its higheze 2dz* ,9 54sdby1lxxmy lhe4st point?

  Suppose a ball is thrown straight up, reaches a maximum height, then,hln*m,ngt.ri9+ tfn:z 9cz rcuh,+y falls to its initial height. Make a statement about the direction of the velocity and acgzyz*9ilc+r rhnt,.u+nf9 t ,c,m nh: celeration as the ball is going up.

  A ball is thrown strax ci+j - ogkq;1mwx e1gxn34;efik( n9ight up, reaches a maximum height, then falls to its initial h; x i-1j9i1 gck +3xeen;mfgw(qknx4oeight. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward i :acol4;lxud 0rq+c 7bn the absence of air resistance. Make a statement concerning its acceler u;qlc0xoc:r4+7d balation.

  Suppose a skydiver jumps from a high-flying plane. What is s:,su,nlwad,4hxz :gdq +d, 84sgagjher acceleration when she she reaches terminalsdjah uw:g4dd+4ql n,xs8sgag: z ,,, velocity?

  A ball is thrown vertically upward with a speed v. Angl 9 epw-h42+j c5fnct identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height ofl tgw4n-e92fj +5hpcc 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 of a building.j,w knq m2njbiwn-/ 9qn2s+0b01 yk+d2fum rz One second later, ball B is dropped from tk1bmmznjq+iw 2+yn- jqur2 k9 ,n ds0/fw2bn 0he same building. As time progresses, the distance between them

  Ball A is dropped from zqkt+cgfztv 81uib9 :m6/ 6uk the top of a building. One second later, ball B is droppek:vtcu8 9i +tfzb1gq6k 6m/zu d from the same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One i9.wnmmt;6 ztxs thrown up, and the other is thrown down, zm.t;x 9t n6wmboth with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A )9+p77 vbtaolb yxs c*a:b2j msecond brick is thrown straight down from the same building. They are released *aj7xat+bbp:7m)o lcs2 9 byvat 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. The d+j bt5/ps;b z5+6dik9fp xk rposition versus time graph of this objectkbkr;z6j59+d 5s f+b p/di pxt is

  An object is moving with consta )qienl5z6* t+ble nkxvzzq -q8-e -c1nt non-zero acceleration in the +x axis. The position versus time graph of th e5-q8qzeixklc- tn)6+1qnb*l -ze zvis object is

  An object is moving with constant non-zero velocity in the +x ax 7.c,rd *;xox ipxgq1bis. The velocity versus t1bid;x*rg o7pqx, c .xime graph of this object is

  An object is moving with constant non-zewm db nmav2s8 :g bn.b3e4+qt9ro acceleration in the +x axis. The velocity vere38ts b4+ nmmdag9bv 2.n b:qwsus time graph of this object is

  The slope of a position ve;2ywns vv mve7i+w 58hrsus time graph gives

  The slope of a velocity versus time graph giv1/gom(cu gqnu+2v v:des

  The area under a curve in an acceleration versym r,);)r kfbmb9 .zlvx9,eg sus time graph gives

  The area under a curve in a velocity versus time graph ;fu.v thc( )s5mdn( i:dval: wdoi)t6gives

  If the position versus time graph of an object is a horizontal line, to juax8.c3)sbhe object i.8a 3)cso bjuxs

  If the position versus tim-r fx0rj z2nt8+*c+rg qbi* ike graph of an object is a vertical line, the object is+k+*rbxnc qg i0t2- r j8izf*r

  If the velocity versus time -edxrn8zpn lq6qg4m ri d)2u dh -6;m/graph of an object is a horizontal line, the object ih i4l-)ddn;-6r8ed rqx/qgzu m 2n m6ps

  If the velocity versus y3hjvd(jnm -o4b.a yrw6 ofe,/4 ca1ctime graph of an object is a straight line making an angle of 30 degrees with th4b .ajyv e/nm4j1-,wr(yf3 c co6ahode time axis, the object is

  An object moves 15.0 m north and then 11.0 m/vq c 2m-lhfrckl/p6f d;m,ahro93;n south. Find both the distance traveled and the magnitude3h6hol9 ln fpa/;cq, rdk/-frm2 mcv; of the displacement vector.

  A boat can move at 30 km/h in still wi/n wodg f+3i1ater. How long will it take to move 12 km upstrw iiognf/d+ 31eam in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1602qzcjg/fx ;z2xdzx-6 qx(qgc5.kc yyk p :j((9 m)

  What must be your average speedtg1 g4n eh9nevg.4 rmy82jz +f in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 m 4.9 nxnp ;crahj :n7u;pb4kcuin. What is the c ;ncx4pk 7p9j na.u;r:uhbn4average speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to travel 400 r, 8ql.hv7;f9xag qra km?

  A ly (light year) is the distance 3 xhq;*4kewcethat light travels in one year. The speed of ligq4k3wh *cee x;ht 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 kmg:1 c(bte, wca/h along a straight road and you look to the side for 4.0 s, how far do you travel during this :a(,cw1 egbtcinattentive period?

  If you run a complete loop around an outdoor track (40 3+d:ulsf3 vky0 m), in 100 s, your averag3 yd 3+s:fuvkle velocity is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.km0fo*qk ( f tyfbo;:v33p d(z0 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 averagetf (z;(bofdky33*mfp:vo0 k q speed?

  A polar bear starts at the North Pole-ox ;o:) 9j9wpakxabb. It 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. This trip takes 45 min. What was the bear'xkw:9j)o- xb; 9po baas average velocity?

  You are driving home on a weekend fro 2lcae )ljg ttjmd9.5bv p)m)ptr:;5vm 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 bjmt): ; p9pa5 j5vr d.2tl)t clemgv)hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. What is the av3y7 45taeqgd7oo y ,w;ajshdh. k. iop-r 1*mkerage speed of tmr.5t7*pi -7jqywy, o1 do4aadks;h.ko heg 3he motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. lwo9yy8 (d-b vWhat is her average speed for theo8yy9 ( dbwlv- trip?

  An airplane travels at 300 mi/h south for 2.00 )xi8al.r rcs+ h and then at 250 mi/h north for 750 miles. What is the average speed fo8ci+ rlr. s)axr the trip?

  In a 400-m relay race the anchorman (the person3 r7 dkdy *rn6rkjpj 3kmhos+s0y26p + 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 the team A runner starts the final leg of the race, in order tmpr khrs* 2yj6ksynd +6r3d3+ok7pj 0hat the team A runner not lose the race?

  A car decelerates uniformy )n 1qbp gpl0*28maqvly and comes to a stop after 14 s. The car's average velocity during deceleration was 72 km/h. What was2bag* v)p1 0m8qynq lp the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, avh3yxsky j+ k8b 5busq8p5;s/:h ;a w xqeb5a;t the average rate of h55s/q;b;+a8s xbk; yxywsh ap 5j38:bveukq$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate;n/ dkx j5x4ettq w9j- 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 acceleram4f8 9j1r7fu:g tl9 pqflq0yi tes 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 )ynowwq 2s1nl 4rup0 -m/s for 10 s. It then speeds up with a constant acceleration of 40w)lpuy2 n qsrn1o-w $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 8.0 m/s experiences a const y0ud ir:j,rner)ps 1,ant acceleration of )nu0r1pisjr, :y,er d$1.8 \; m/s^2$. What is the cart's displacement during the first 6.1 s of its motion?

  A bullet moving horizontally to the rigxgp8vcs9 ) i51;ycf 79eefjvqht (+x direction) with a speed of 598 m/s strikes a sandbag and penetrates a distance of 64.62 cm. What isvvy 1ipx9c 7 jeg8q fs)ef59c; the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an ai6 ,l ocjx tnf+2a7q+eyrcraft 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 6+eonq,atf 7yc lxj+2 the length of the catapult?

  A car starting from rest moves with con )5+ al4h kmuokds/:znstant 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 its avek5rj q9v- aphc. .+zvvrage ach9.pjvk- z.avc 5qv +rceleration?

  An object starts from rest and undergoes uniform acceleration. During the fir33bl n tgej.w4bj * r hd +*tiuvbcxya9,x7v2.st second it travels 2.9 m. How far wilaxj2vhw4it3*g3lvx+ne.. * yu ,tb9d r c 7bjbl it travel during the third second?

  An object is moving in a straight line with constantbbdv k7(mw) x5 acceleration. Initially it isw)xk m5vbb(d7 traveling at 16 m/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 acce:3j 5ssz)rv1mvvqts .lerates 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 ri2vlj,d/(v e0o, oxcpoad 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 tu tdun3q64w3adrns green, a car that has been waiting at the intersection starts ahead with a constant acceleration ntw4 d3du3a 6qof $2.00 \; m/s^2$. 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/s on the surface of uibb oi :xx0dn8 10+soplanet X where the acceler8x1+is ub0boi0d:xo nation 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 of 12 m/s on the surface of 8dpon92 (ta(g2( hb 8 wk hha;tktcu3gplanet X where the acceleration due tohd( 8 93k2bcnt(w ph;gg (tku a8hoa2t 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 surface of plan (+o qwy7u.bspet X where the acceleration due to gravity is 7u(y+qs p bo.w$2.5 \; m/s^2$. 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 :8xrpsays3 / dsurface of planet X where the acceleration due:y/8xds3s rap 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 your friend holw4m ;,aqq73ucdlq-b k ds a ruler between your fingers and releases it without warning, how far canqm-;w3d7 cqbkuq ,4la 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 velocity afte3 yefp41aijk *r 3.00 s?ayj4p 3ke 1*if

  A bullet shot straight up returns to7i)gc5,j obmj+z tl; w its starting point in 14 s. What is the ingtz wj)ljc, 5om+i7;b itial speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does itmx.uw2 - fpm+ zhz)vvd.(x v/v take to return to itw/xhzvp vv)dv.f-2 ( xmu.+zms starting point?

  A ball is thrown downward from the top of a buildinguc..rsr:m: iy a6gnj . with an initial speed of 29 m/s. It strikes the groundcuai .:r.: .6mryngs j after 3.8 s. How high is the building?

  A ball is thrown straight up w/entc bf 3tp9g2).oz fpd /b8hq( qa)pith a speed of 30 m/s. (only fill in numerical value in thcfoq)h/p()g2pnbpe3zdb /qt 9.tfa 8 e 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 ; 0j50duzbz jrjhiq1 ;the air with a speed of 25.7 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 2 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 velu7qu)3x hoy(( d6 pqjn- .ldsvocity at t = 1.0 s?

  In Fig. below, what is the velocity at t = 2.5 wlvo f 4d1:k(w0, gatxs?

  In Fig. below, what is the velocity at t =1vmn* y)kd: l4kvn2j wlta5: v 4.0 s?

  In Fig. below, what is the velocity at t = 5.5 5 anxyws,6:a gs?

  In Fig. below, what is the average )grxl0wqe0a-s : al,v pbq07:zqaa*tvelocity from 0 to 4.0 s?

  In Fig. below, what is the averagerx7ekg8f *fk)jh up(( velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration xk 4krueu9t6a:/y-if at 1.0 s?

  In Fig. below, what is the acc4k tlzm*uk6e i:i+)cieleration at 3.0 s?

  In Fig. below, what iszi2+s .fk (jndwmf8cd*+pcj 2 the average acceleration from 0 to 5.0 s?

  In Fig. below, what is te k9tr(dr1ksk92- pkvhe average acceleration from 0 to 8.0 s?

  In Fig. below, what 0iuth1uh)(hqf /lrj04 h/q vdis the displacement from 0 to 8.0 s?

Does a car speedometer mep n(w+6s dj3xiasure speed, velocity? {speed|velocity}

  An object can have a varying speed if its velocity is convlzwt*ujrwx/ 7g:d (7stant.

  The velocity of an object can be negative when its accelerk5cerf(+c1loeg mqzo,/ qa 8c1o 0i 6eation is positive.

  If one object has a greater speed than a second object, the first must*f t/kc 4-zr;tnwlnre 2hq ub8n(9h ;e have a greater acceleraw(ne lnz4krqrb2ue;-8;ct9h/n tf h*tion.

  Two cars emerge side by side from a tunnel. Carly(, v2 0yldst ;0 vs 2ga hvr+tjfa1qujg*2u- 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 d +q 0h;:siokeh:kg1zmecreases.

  A baseball player hits a foul ball straight up8mftrxni *h mudp,y 67n-63yj into the air. It leaves the bat with anythjdn, x *m-6 7 f3pmrui8y6 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 up, what is happening to its accelerationw50btws d1z(zzsw ( b., howdstwb5((wz zzbs 0.w 1 does it change if air friction is ignored?

  As a freely falling object speeds ubucr -0:;hwle p, what is happening to its acceleration, how does it change if air friction rl w;:-e cbuh0CAN NOT be ignored?

  An object that is thrown vertxmc7;abu+f h 5j 7k*x- ytx17nk4guboically upward will return to its original position withoxfu1- hx5 y*j74n+kt7 cxkg a;bmub7 the 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 the same tim3kfqrh 25p3j55f iq)pkq g zeqc/t6u 0e.

  An object can have nonzero velocity and zero accypqt:49eb( i.r pw my (aadzo5*r:jc1 eleration at the same time.

  An elevator moving from the second floor to the fifth 1+ . hlrhk2vhr-/ gvqqfloor making no stops along the way has zero acceleration all t v .k1qr-rqvhl +gh2/hhe time.

  A rolling ball moves from ncxq4hfd6r4xn 0s1 ) q$x_1=2.1 \mathrm{~cm}$ to $x_2=-8.2 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ 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 $t_1=-2.1 \mathrm{~s}$ is at $x_1=2.6 \mathrm{~cm}$ and at $t_2=3.8 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps aromgqapvg*j u:a- -p62hund a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.2 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,jup ---kb d-xp moving 99 m away in 11.8 s. It then turns abrupdux b--pjk-p-tly 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 fromixi1h6+d a)a esj(v0d $10 \; m/s$ to $24 \; m/s$ 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 fromtcd49 px+lp,2)i8 cry s:mgak $21 \; m/s$ to rest in a distance of 76 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a spee)gmb*d bk xw,9c*k1eqd of $30 \; m/s$ 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 essentialsxd kdq i q:cd(8r, p)kx/6i//vxin1 tly top speed aboutnc:xvd (ddki / 6r1qxp//qxt) ksi,8i $10.4 \; m/s$ in the first 14.9 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 -p n 2hm1wo;(dba ayl2+wsy1from a speed of $16 \; m/s$ to rest in 4.97 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 : d -q4j h+e,wvencd54fc*hay bm.tw -on the highway. Assuming a deceleration ofme- nfbjh.c4:d* ahdq+vw5,cytwe4- $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck 5hlosf01 lz0os*qe 3xgoing $25 \; m/s$ 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 iuj; a90 5t q/2hase 9 kxlnyw:7*jro3db(evhin less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then acceler;e9sja93/j*lk wd0avu2: r q7bey tohi x hn(5ate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$