Suppose that an object travels from one point in space to another. Mak hq4e-q 0b:mzue a comparison between the displacement and the dis0m- z4qeu:qbh tance traveled.

  When is the average velocity of an object equal to the instantan nz3a:-fkgvd9 n8+tdveous velocity?

  A new car manufacturer advertises that their car can go "from ze 6rplt,t zno3 fe28ih9ro to sixty in 8 s". This is a descript i3 f6 o2t8htzp,9nlreion of

  An object moving in the +x axis experienc-,bzy:cll 3b*b lk,s xes an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begq9twui9,(csf a1.*e zcy 2l m xh(u/okins to slow down as it approaches a traffic light. Make a statement c*sfkh1cz ,yt.x9olau / 92m(iew q(cuoncerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow down as i: ,(nz:gaczpv t approaches a (,: zznpg :acvtraffic light. Make a statement concerning its acceleration.

  Suppose that an object is movivb)t3qt/v 5l1hete tt4o8cb kz0:dy7 ng with a constant velocity. Make a statement concerning its 0tvbe /t q 4o3k5v:y8zc b7t dtteh1)lacceleration.

  If the velocity of an object is zero, does it m*l5x kl9o3kz5n1m8ejhl 4dta ean that the acceleration is zero? Support tekh9 4j1* dxmano 55l83lzklyour answer with an example.

  Can an object's velocity change direction when its acceleration is constant? Sur kd*(dz28i 9m s0iz; b7ywtbxa3pu5vpporbdux52 pi80i3 vr7 b;z(kd*9st yawzm t your answer with an example.

  Suppose that an object is moving with constant acceleration. 1avbddv ;:hw4rtt2 s+ Make a statement concerning its motion withwh drav+4t2t s:d b1v; respect to time.

  Can an object have increasing speed while its acceleh tnd 8i6l.kis(h4.2i pn 5julv5,xpnration is decreasing? Support yourn,6p852(tx dni hhl4sji.l. nkvupi5 answer with an example.

  Suppose a can, after an initial kick, move3q9xkm( e8zt(o h ai3gs up along a smooth hill of ice. Make a statement concerma8h (3q tekzg9o(3 ixning its acceleration.

  Under what condition is average velocity equal to the average o2brv p.,pe :kv,vuel0h:0zligy t4 ,hck ,dt;f the object's initialp etk:4,zy 2tlgrk epi:v,lhh b;0u .v,c0,dv and final velocity?

  Objects A and B both start at rest. They both accelerate at the sam cn2h7fdf,t e:e rate. However, object A accelerates for twice the time as objecdh ftef2c:, 7nt 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/gax t.7t4nqa. However, object A 7xq. gt an4at/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 and4 cvdv 3sm:0kk falls in the absence of friction, which of the following is true concerning its ck s:k40 mv3dvmotion?

  When an object is released from r*u4v xfem x*w,est and falls in the absence of friction, which of the following,*4vfxx e* umw is true concerning its motion?

  Suppose a ball is thrown strazq ot 1. 2oaou3apb mixg/*63tight up. Make a statement about the velocity and the acceleration when the ball reaches the highest oap 3 o xt/at*zo3q26uib.mg1point.

  Suppose a ball is thrown straight up. What is its acceleration idn; +r;zwgujjzr+5yx*i (3ec; -wtp just before it red n;rc3 ; gzt5 w;-jrui+jip*x(yz +weaches its highest point?

  Suppose a ball is thrown straight t0g6 o+ bst.y;u6wrh rrayt *+up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velott+s 60oa hrwyb .*r+tu yrg6;city and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a ma,n3 3cdc0 .d9 pejwvapximum height, then falls to its initialawc dp 03vjc 9p,dn3e. height. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downwar qj.7v)7dkjt z7exz1z,o o+mx d in the absence of air resistance. Make a statement concer7 vj1xxzzd7 +qe,)7km tz.oojning its acceleration.

  Suppose a skydiver jumps from a high-flying pbm q: jhx)w5hb sp*nf v+,,d erjf9d)5lane. What is her acceleration when she5 5dh+vm*wx sj9, ,:j )bpfbnrq)edfh she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identical secon n p /z7w2bdkkkzjf83lq ph,2 3wq s1ovy.no9:d 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 m3hql:o v3/nkzonf.ps2 kywjdz1b q ,8p 2 97kwany times higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One seconxh5jjq2k-w n,0m inf-d later, ball B is dropped from the -iwjk 5j, x2nnf0 h-mqsame building. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One second later, ball Bad1 xsmjw+* ykpn4m. 19oq.vq is dropped from the same building. As time progresses, the differena.wq4 n.o v+9xp1j dy1 *mqkmsce in their speeds

  Two objects are thrown from the t.ll4h yeo l;80v 4tuyuop of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What areyv.y84u 0hll4luo te; their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is throw2 .l3n4ydhvat31u051bb: ,azylpcklln 5zw xn straight down from the same building. Thulc 1dp l:5lyz ylvkn.w4ta 2,5nax b1b0h3z3ey are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving witm 0--wqevc xc/mr-gp 2h constant non-zero velocity in the +x axis. The position versus time graph of p g q0--mevm2w/x-c crthis object is

  An object is moving with constant non- zws0i0n no)*ahk:/ vquup(. ezero acceleration in the +x axis. The position versus time giankh:e* vnoz. 0 p)u(0u/ sqwraph of this object is

  An object is moving with constant non-z hg r-glimk12d1u8p4.7cloyn ero velocity in the +x axis. The velocity versus time graph of this objek u 8dmo c1g72ilyrl4 gh-pn.1ct is

  An object is moving with constant non-zero acceleration in the +x axv mu8b9t/r6-*h j5uu by,g wec(ff u7xis. The velocity versus time graph of *ebj9bw,g 5v /x 6u8rfum-fh u7uct(ythis object is

  The slope of a position versus time graph gix 8o cwr-*trs9ves

  The slope of a velocity versus time graphm 88fs mlu8-84fg f0rlidp .vz gives

  The area under a curve in an acceleration u9x4 rpch5dh4 versus time graph gives

  The area under a curve in a velocjsd60--ay zj* xqs xi1ity versus time graph gives

  If the position versus time graph of an object9/a 73qu.fe idu ,ofjv is a horizontal line, the object uiea d,./f9q o3ufj7vis

  If the position versus time graph of an object is a vertical lineo2rh91 cw1ah- 06kv :bv qeyme, the object isba 6q:9 v11hoecm-y 0rkev2w h

  If the velocity versus tks.md8,x- vl7ie /kd.u0ek ay ime graph of an object is a horizontal line, the object i 0k .k ey- si8aldkduem7vx./,s

  If the velocity versus 9m/kdhz*3 3pal9ck5o ,cf,ekvcx6 iptime graph of an object is a straight line making an angle of 30 degrees with the time axl *ckkif cv3 63cpd/h x9pae5o,,9k mzis, the object is

  An object moves 15.0 m north and then 11.0 m south. 1hirch:f kq8 4k*g1ji Find both the distance traveled and the magnitude of the displacement vector8:4icki hghq* 1r jf1k.

  A boat can move at 30 km/h iy: dskx02 f3lv*ni,mo.-vwpdn still water. How long will it take to move 12 km upn.s0 * l:iw d-,kp3ov2dfyvmxstream in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? v nbvikduj g;: sgq y./h20y7+(1 mi = 1609 m)

  What must be your average speed in order to travel 350.skz64 u2), rdrq duiw km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 minwc +t13l yvnm;y 9n)fa. What is the averamya flv1+nctn3; w 9y)ge speed of the runner in m/s?

  A car travels 90 km/h-f ,:vz)5 3r6mojsohnadds:j . How long does it take for it to travel 400 km?

  A ly (light year) is the distance that 3cq3v6 f ly0splight travels in one year. The speed of light is pqlf063yc vs 3$3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 72 km/h alo r c-r;sh-.bftng a straight road and you look to the side for 4.0 s, how far do you travel during this ina. ;tcr-bsrh f-ttentive period?

  If you run a complete loo1*kle-q u *v o;.ktzhkp around an outdoor track (400 m), in 100 s, your average velocityk e -lo;1*t ukhqz.v*k is

  A polar bear starts at the North Pi: evwa45u 7cup-7, isxpy::sn u6bm )f8ign iole. It travels 1.0 km south, then 1.0 km east, then 1.0 km norxi46y8bv uifws:757pas,u ) iucne:-i p mg: nth, 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 Pqopplcqk8 i) tr4-+ b(ole. It travels 1.0 km south, then 1.0 km easrkpqq84b-)opc+l i( t t, 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 average velocity?

  You are driving home on a weekend from school at 55 mi/8it /p udz7w-uh for 110 miles. It then starts to snow and you slow w d78ptu-/uizto 35 mi/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/h and 160 km at 100 km/gj(4j uj(ksx ;zo +bs3h. What is the average speed of the motorist for this trik+ 4(zjs(bjsjx3;ogu p?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is hmf 7b 6v,em-x):nsuower average speenomm b7x, s:ewf)-vu6d for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 2l46 k) u7of: yki:cyx3gpcf:l50 mi/h north for 750 miles. Whatcoplcf:7 ykx:6 3ilyu:4k fg) is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for te5nx/ t ;.gwzcl9aw 8diam 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 tw 9c.x 5;l8z gwa/nidthat the team A runner not lose the race?

  A car decelerates uni v*tavv j71 1(uyv+lmiformly and comes to a stop after 12 s. The car's average velocity during deceleration was 52 km/h. What was the car's deceleration whi7vvj1mvlt +1v( iuy*a le slowing down?

  An airplane increases its speed45nth4emtx u + from 100 m/s to 160 m/s, at the average rate of uttex4 n54hm+ $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accely a 8:koej*a2g6t t,maerates 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 accelerate/9bg4b3bfnd, yr x, bxda4)p1fd-f ibs 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 fy+7otgs zq9ck4(p/h qbki,;a constant accelerationpiq4ky; b+(gk f, c9s7/thzqo 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 2.6 m/s experiences a constant acceleration gfh31ly 4d3 ovolhvdo 1fy3g 34f $1.3 \; m/s^2$. What is the cart's displacement during the first 4.8 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed1 zf(zu( k59c-bfs+czf vc14s7-gxm4 tos u xt of 236 m/s strikes a sandbag and fuzcbt94+ 1c czsm-guf( z5o1 sf(k- stv 7x4xpenetrates a distance of 32.71 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on anz)b0bs ya,u /ojrx* d*c28 ipf15 ajkd aircraft carrier. It reaches axs/p da),2az 5d* 0ikuo r8j*bb1ycjf 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 catapult?

  A car starting from rest moves with constant acceleration z) n8;-tbos(e*oexkir n*- tuof $2.0 \; m/s^2$ 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/j swme+ .+sky3s to 80 m/s in a distance of 200 m. What is its average accy.s+jkes w+3 meleration?

  An object starts from rest and undergoes uniform accel0 31pv(vvpodh: 8aumaeration. During the first second it travels 5.8 m. How far p0vodv:p uah3(8v ma1will it travel during the third second?

  An object is moving in a straight line with constant acceleration. kdtpo; g4x/yp fho5d*yh //. cInitially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during pxyygoc/kdp f t ;hh4/do*.5/this time?

  A car starts from rest and accelerates uwal+kv1 tj/z7niformly 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 yz-e (vr,7zgxg0rzp 8dry 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 that haso l:3 /y(v (w0iu-c ywmgw(md)h1w.a/wguy oq been waiting at the intersection starts ahead with a cons uyw oqc)hg :gwmy1w(w//3wm -i a(vdy.ulo( 0tant 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 speed of 12 m/s on the surfa d4k/8koxljzt. y)ww-e(dgp/ce of planet X where t/ wexd8zokwpt l /dk(4g .)y-jhe acceleration due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown z) *2tq 0anti3 iuodxd(fi-9wupward with a speed of 12 m/s on the surface of planet X wher(xtf3iq90 izndu2) wod-tia*e the 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 a speed bkbf *v2i x2xft0; 7yyqtfh6y nk/ )n og;-hf5of 15 m/s on the surface of planet X where the 2*kiy/h 2bx5n)-t7n q gkffvfy0;ho6;tbxyf 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 14mzr2xhc2qf f *; rdc;a7; s8phy,jx /n m/s on the surface of planet X where tcrn2hqf;/ 7c;dh; za* fmx2y jrs xp8,he acceleration 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.o evi rvym92/io)4bq( 10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fall before youeq2vrv(o i9)oiymb4 / catch it?

  A ball is thrown upward at a velocity of 19.6 m/s.c6r d+7d9a mca What is its velocity after 3.0r mdd+9ac 76ca0 s?

  A bullet shot straight up returns to its starting point ins3vc yfjppiq;: 3+vg:wj grk2k6po2, 10 s. What is the initial speed of thkkj, cgypsp+o 26 3irgq f3w2vjvp;::e bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How lonnyl g7(nqx9epdf0y l,fztr6mq 30)ygf7 j 62sg does it take to r lq0,3smrne6n gqyf)(72yj0z9 y7p 6 dt flfgxeturn to its starting point?

  A ball is thrown dowh9f1p n00nnn6oi:rslaoj8w zu;,mq 4 w7(oftnward from the top of a building with an initial speed of 29 m/s. It strikes the ground mw jlu6z ta80no is7o4 nforwn0p;1(9qfh, n:after 6.1 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numerical .ecxv h9iizih :4ha2;u/:bt7tkp ky* value inuit*4 kheh ;x7y:z b.t2 i/ikvhc9 a:p 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 kj :(h f)qxz,eup into the air with a speed of 23.2 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 velov* igdswcn)7:y8 7s jwcity at t = 1.0 s?

  In Fig. below, what is tlpmq7u j+;8g *c5xeo k/jydrw lr:; ,xhe velocity at t = 2.5 s?

  In Fig. below, what is the velocitzbu5dh *xfsp9sgxs+ d/( k9 a(y at t = 4.0 s?

  In Fig. below, what is the velw p- -w0f9kq,irsov,i ocity at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to g 8a)ty05fsh b4.0 s?

  In Fig. below, what is the average5:wn s4p-d ah 0p nqxt:u/*k3tzz6jyg velocity from 0 to 6.0 s?

  In Fig. below, what gex.xgky 9f3tv*pg2 x/n.4r o is the acceleration at 1.0 s?

  In Fig. below, what is the acceleratio(s f -6uh4bazcn at 3.0 s?

  In Fig. below, what is the avjfxxzldjx 4 92;8yi u8erage acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.0 s:rd -2rjbiklkaxo: 0 *?

  In Fig. below, what is the displacemenjkd1 n:wj1:g8wk9 d,q+h+z rojd b3zmt from 0 to 8.0 s?

Does a car speedometvj ,w c;h,1(-oq/f0sxs dz3f:dshseaer measure speed, velocity? {speed|velocity}

  An object can have a varying speed if its velocy zqr. 48xh)lsoti3h4 ity is constant.

  The velocity of an object can be negative f gut6ysv g0b.m2((oz when its acceleration is positive.

  If one object has a greater p urx x +yr:s-vly;)x*speed than a second object, the first must have a grp: s+x;urvryxyl*x-)eater acceleration.

  Two cars emerge side by side from a tunnel. Car A is traveling withj zo/;om/fw v1 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 a,csbs7*xd( sx0+;mm8iwv sticceleration decreases.

  A baseball player hits a foul ball straight up into the air. It imw4l: jx1e/g4orgwj,9ad;x leaves the bat with:4 jd 1w94o/iggxle,rm;axj w 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 +yivq+eju; h1 0;ynbpqi;o- b object speeds up, what is happening to its acceleration, how doeshuq qv0+ pyjb1+b;;y;i-eni o it change if air friction is ignored?

  As a freely falling object *irs*a6o iqbi3e7s:muq 2j- o speeds up, what is happening to its acceleration, how does it change if air friction CAN NOT au7iqe s*r 2-*q6os3bj:mii obe ignored?

  An object that is thrown vertics in c4-c7ovt./vhb .pally upward will return to its original position with the same speed as it had initially if .s4.nthicovb- cv/p7air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have ze k(bh1hta8.ffr t:2 x0j)sjt hro velocity and nonzero acceleration at the same time.

  An object can have nonzero)idim4vg;j; b+ wvybx cu 9b49 velocity and zero acceleration at the same time.

  An elevator moving from the s(l ym sjni9k(lr4e: k0o3f,.s6a iehjecond floor to the fifth floor making no stops along the way ln( lfea 4k396ys: i0e(si,j komrh.jhas zero acceleration all the time.

  A rolling ball moves froma: 4+n(sqbue y $x_1=2.7 \mathrm{~cm}$ to $x_2=-7.0 \mathrm{~cm}$ during the time from $t_1=0.8 \mathrm{~s}$ to $t_2=5.2 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.3 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.8 \mathrm{~s}$ is at $x_2=7.7 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight crzf*0;p m 2vpcomplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 12.5 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away fronp u(b4lf,/iywy r52x 8s*ni25rw lvam its trainer in a straight line, moving 86 m away in 12.6 s. It th a ,l(2iypw4rwlib5n vn5fy/sxru28*en turns abruptly and gallops halfway 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 from qcw;u*zukql4 + .o9yc$12 \; m/s$ to $23 \; m/s$ in 4.4 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 from 5fwf e +yo3ck0-de1yh $17 \; m/s$ to rest in a distance of 58 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed of /p; dbl:mv hf6$32 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.8 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top sp.a0rn wsz+pgy3m t50yeed abouymsay. 3+ zpr nt500wgt $11.5 \; m/s$ in the first 13.6 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 frry f-kxz lpq7ei5*5:l om a speed of $15 \; m/s$ to rest in 4.73 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks geldur2q,g7alup.y 7 ry6+2 r 92 m long on the highway. Assuming a dec r6q.epd2rg,gr + l l27ayyu7ueleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a tru4/rm, a29yz(lqz,f,mi j zxqtck 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 les.jeb6u+ el teo)b- cd/s than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The run +/ j)c-6ebeodube.l tner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$