Suppose that an object trafs.np3ub(;wl vels from one point in space to another. Make a comparison between the displace(b uw;pl n3s.fment and the distance traveled.

  When is the average velocity cz*le 3.vp .qiof an object equal to the instantaneous velocity?

  A new car manufacturer advertises svv.bw816 l* mgy +w8weuxy5,qz0bz g that their car can go "from zero to sixty in 8 s". This is aw8gz8,1 sxzluyg6wy+ ev 5 0bw*.vm qb description of

  An object moving in the +x axis experiences an acceleration ;vtaty . nc-gnix v:13of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to th8fnx pet1*fbc. (d j)xe East (+x direction) begins to slow down as it approaches a traffic light. Make a 1fcx*(fbt p .e )x8djnstatement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow d6 6yeyxt-fs;n*8jix r ) 6cpsxjw,j 7nown as it approaches a tsc 6s8yn6r* 6x )j ,jxfi-pxwnej ;7ytraffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a consta,o*-k p4 ( ev9ci7qeguk7zsn6,ko mqx nt velocity. Make a statement concerning its acxi(,e7uqp zoqk-nosk*7 , g 49 evk6cmceleration.

  If the velocity of an object is zeropw66glsieqd3w z+ 4o3, does it mean that the acceleration is zero?3o6ig4z+3pd wsqlwe 6 Support your answer with an example.

  Can an object's velocity change direction whq lu/: m7nni )ylah42sen its acceleration is constant? Support your an) 2u llsa:myq7in 4hn/swer with an example.

  Suppose that an objec ,oedtsid0. od1khs z: o(8 ,4hf.mji2p)ualdt is moving with constant acceleration. Make a statement concerning its mo 1af pd0,ostd2hi(zuji: mdh)8 s,.l e d4ok.otion with respect to time.

  Can an object have increasing speed while its acceleration92r8 i99 vs.jnq .w+yi kwuesq is decreasing? Support your answer with anwusq2e.iq9rvsi9yk+ j 8 w.9n example.

  Suppose a can, after an initial kick, moves up along a smo (ejx61 kv 7;qjdhsml*vk d-t4.rgv8ooth hill of ice. Make a statement concerning its accelek8rjh-;vjl14xdk6ot. vmeg 7 dqv* s(ration.

  Under what condition is average velocity equal to the-de hzqpl5 33n9hx ag6 average of the object's initih53q6 9a3d-gnhzle pxal and final velocity?

  Objects A and B both start at rest. They both accelerate at the s10q ,otybh mx4ame rate. However, object A accelerates for twice the time as object B. What is th1,qxyot0m 4hbe final speed of object A compared to that of object B?

  Objects A and B both start from re,: r j,c2jc/;b vucfpln+n,qfst. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A comv/2, l fp:,f;rnj+cn j qccu,bpared to that of object B?

  When an object is released from rest andiy 4b4 d8 yv.;cte guq9g9wii6 falls in the absence of friction, which of the following giv9dtb4 ywq6i84cyi;9 u .egis true concerning its motion?

  When an object is released from rest and falls in the absence of frictu7bom y 4t pbe-olot fv)s(npp 0ct2l0*h67o1ion, which of the following is truhbt no oup1 tvp0y)toms*(oe f4 - p20l6c77lbe concerning its motion?

  Suppose a ball is thrown straight up. v ).z)zwvie3r Make a statement about the velocity and the acceleration when the ball reaches the higzvz.we)) r v3ihest point.

  Suppose a ball is thrown straight up. What is its acceleration just before ity:vx.axbp) bo51 -c gz reaches its highest poxb:pb.1g)vc az- xy5oint?

  Suppose a ball is thrown straight up, reaches a maximum height, thhgx/c x nh+di7jy1 (6ken falls to its initial height. Ma d6gij/ck xn+h7x (1hyke a statement about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum hu*/ j9b9pnzewu7wks+ azvv8t).2ne reight, then falls to its initial height. Make aujv 7t8 .+erbzw9se2w )upk/9nvzna* statement 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 resistance. Make a statea t tnm+ d2u(26dqk.jtrt x4,obxx,.mu 7xo)hment concerning its accele+x ( ,djxxr.qx t)hu 6ttbmma2otdk4 u27,. onration.

  Suppose a skydiver jumps mj6-jx kdnb**hfme)5 from a high-flying plane. What is her acceleration whe jxn-mj*b )*5mfd e6hkn she she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An,0l-vm9 b+r:r p4 ;spspaj *yj0rrcsm 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 high ,v pr0rppml;*a:4sr0jm cbj+9ys-srer does the second ball go than the first ball?)

  Ball A is dropped from the top of a builuh, k.2txi1e:yg p r8x 8nm4cdding. One second later, ball B is dropped from the same buu8dthxyp:n g,k.x2m er814 i cilding. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One second later, baln byns yl*d+i-, 9ieg.l B is dropped from the same building. As time p-gb es9,.*d+l yny inirogresses, the difference in their speeds

  Two objects are thrown from the top of a vy)z8.98fngla oi tto.mydjc); y1v;tall building. One is thrown up, and the other is thrown down, both with the same inotm)ynja lt)8y1c.d.z;v f 9oyiv;8 gitial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick i:h21okn xoec:4wroi j+ k.g1ss thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare cxensoj ri 1 o+w4ok2h1g:k.:the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The pxa,2h -7v;m ju,m j wj/4s zlgvj6i(hhosition versus timel,vxhj47(2uhswi; vmjgz/ mhj6 -,aj graph of this object is

  An object is moving with constant no.emgdkd9*t7d n-zero acceleration in the +x axis. The posi gt.*dd7 9mdektion versus time graph of this object is

  An object is moving with constant non-zero velocity in the +x gdn2c /sc)*ux axis. The velocity versus/s)*c2ugdn x c time graph of this object is

  An object is moving with constant non-zero acceleration ovc.m;5 kk(y7hwtr pzhbw es9yz 046/in the +x axis. The velocity versus time graph of ;p .trcm(zkyo76/0b9wv e4 hh5 ykwzsthis object is

  The slope of a position ver)u6, i9 ew cx4mpjmun-4. nknusus time graph gives

  The slope of a velocity versu:r *hrb:;z .lgcvn.recw s77 qv )cbe(s time graph gives

  The area under a curve in an acceleration versus time gr2j4m6dj3a irz aph gives

  The area under a curve in a kp(j+xux z23-lh1qw w velocity versus time graph gives

  If the position versus time graph of an object is a horizontqt89q.3s-wwc h6 t pfsal line, the object 63-ssq hw8 t cft.9pqwis

  If the position versus time graph of an object is a vertical line, the o em5gl sj9aup+1nb+*ybject islpm15san*++ b u9je yg

  If the velocity versus time graph of an object is a horizontal /9 .g;o2 qae6g dblayfline, the object bqo6l.dyag 9ga;/e2 fis

  If the velocity versus time graph of an object is a straight line mak4ufny7 8j, io vvgm1.qing an angle of 30 degrees with the oj v. y v74i1fn,u8gqmtime axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Finx7r j1pcu yxn *0pa;0w fiw8y,d both the distance traveled an8,7yxr f0i a;0pn w1yc*jxwupd the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it take52kuv+7qltr lveu nf/y;cy(qe .0v2 z to move 12 km upst(.+;z2ee v c luk5y/ q2frvy7ult0qnvream in a river flowing 6.0 km/h?

  55 mi/h is how many m5s5if10 avfpt5wsgj nx2* gr)/s? (1 mi = 1609 m)

  What must be your average speed in order to travel 350 ktvic8 y,,m :d b0y a4qi*bkw:fm in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours an zphrkii1xgnvr 20tz8d(wc(2 t cv4.: d 57 min. What is the average speed of the runner k 0t wczp:r.(dht8 iz(gx c4vvi2nr21in m/s?

  A car travels 90 km/h. How long does it7k;-8i, zttcwxd6tfv take for it to travel 400 km?

  A ly (light year) is the distance th yq4l5a;*xpnx9uco3d lxdx 1 /at light travels in one year. The speed of u dx*59/3x4pxon l1yqcad ;lxlight 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 alon:i: 1m0 gidtvzg a straight road and you look to the side for 4.0 s, how far do yougid: mv1zt:i0 travel during this inattentive period?

  If you run a complete loop around an outdoo 1xm96cd(haey r track (400 m), in 100 s, your average velocity a196mcxde (hy is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 xdkal+9tp z :vh126*i oduu1vx-b 2uzv) z+a ikm east, then 1.0 km north, then za1*i+ 2zi6l: vuvkxt oa+v-p2 h xdzuu9)1bd1.0 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 travelo4ykdrl.k*wnu5dum w )ug /:,s 1.0 km south, then 1.0 km east, then 1. .kud wnyl5/ g4rk,ouw mud:*)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 schr/-sr.dj o* kdool at 55 mi/h for 110 miles. It then starts to snow and y*-.d/rj s krdoou slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 +wvwy3mjf/ 5fbo( :v*sg.( h, snxjn ukm at 80 km/h and 160 km at 100 km/h. What is the average speed of the motorist fonf v*3x n. /(b sjwsgmu(o w,5hyfv:j+r this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0w+yijk 9kqm .;i/3o(0p y+ciu gmcq5f h at 100 km/h. What is her average speed for jiiyy w5 pmkic 03/ko(g9 qqfmc+u+; .the trip?

  An airplane travels at 300 mi/h south w1gazwtj4 gx52ma00k x48rb bfor 2.00 h and then at 250 mi/h north for 7x 1zr agwgab02mkt x4j wb458050 miles. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for te nyyl4hm1-:or wo, d lujm48d)am A can run 100 m in 9.8 s. His rival, the anchorman for team B, can cover 100 m in 10.1dyh:wu -o 1rmj48nyml4d ) l,o 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 that the team A runner not lose the race?

  A car decelerates uniformly and comes to a stop af0pa;)if3jtdg,z- avc0; dq j fter 10 s. The car's average velocity during decelerationct pdf 0dja03zqj,;ga- fiv); was 74 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average ratc wbq:-7w6u4 dp er:bse of :4w-:qred6ubpbc 7 ws$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at cdcv: +1xi.zn 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 at8e;y*md c d ckzx5i72nd accelerates 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 folm(9i xt/xop+s5 cd 7qr 10 s. It then speeds up with a constant acceleration d5qpc9+i sxlmt7 xo(/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 2.5 m/s experience,m kjs a*v x 8rvni562v3yr*zfs a constant acceleration ok rjv2yvv,zaxs6fm 3 i5r** n8f $2.3 \; m/s^2$. What is the cart's displacement during the first 8.0 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of wq4 d1f1f1 ji*huie;lrf+ vu5346 m/s strikes a sandbag and penetrates a distance of 23.13 cm. Whh qe +if4vfj f5;u ui*d11wrl1at is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catajvxl50k+.b, uv6bet b,u h)xfpult on an aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, )kf5huv tb .+ub0,vbe,x 6x jland 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 mfe 4mi,j1mdh4,k* fwof $2.0 \; m/s^2$ 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 it7g9c.ies(ljkxt t*;d s average acceleradgtek97xt (s;.i*j lc tion?

  An object starts from rest and undergoes uniform acceleration. Duringnkb rp:mkpp 4a3pm(/; the first second it travels 2.9 m. How far will it travel during the third seconppm /3(ank4;:k mprbpd?

  An object is moving in a stc;q3j d84imq d,7tlg,qwi g+ iraight line with constant acceleration. Initially it is traveling at 16 m/s. 4j7gil iq ;d,q wc,itg 38qm+d Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerateh:f0-peh0 *3 xl8oeuu boreu(s 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 ca et9l(qtu2ng(ixo k msu+o5 2atc/ o1:n 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 turn2 1h1dc7k ooraw8tnd (s green, a car that has been waiting at the intersection starts ahead 1 kn1 r2d7d8oa (hcwtowith a constant acceleration of $2.00 \; m/s^2$. At that moment a truck traveling with a constant velocity of 15.0 m/s overtakes and passes the car.
(a.) Calculate the time necessary for the car to reach the truck.    $s$ (only fill in numerical values)
(b.) Calculate the distance beyond the traffic light that the car will pass the truck.    $m$ (only fill in numerical values)
(c.) Determine the speed of the car when it passes the truck.    $m/s$ (only fill in numerical values)

  An object is thrown upward with a speed of 12 m/s on the surfac3)rz0*p exxuu-zujeyrz//7 o e of planet X where the accelerauz0 rz/3x x u)r*ejp/o ey7-uztion 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 surgokv:kj(ulc, ryy/ feqw 5u3r ff152/ face of planet X where the acceleration due tow/:kuc2 g k f5e1for3jlr y (fuy/,vq5 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 o9zumybj7je 1) f planet X where the acceleratiomy eb9juz 71j)n 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+b 3:n q5tbte5ju1u* qilke-s on the surface of planet X where the acceleration due to gravits:euqt+ i*t u1jqb b -ne5l3k5y is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time ir/; r 1jtmq5qvs usually greater than 0.10 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 you catch qrvmtj;r/q 1 5it?

  A ball is thrown upward at a velocity of 1an+d:;tv6hm t : ijau19.6 m/s. What is its velocity after 3.iv+ a :judm6;ta:nht1 00 s?

  A bullet shot straight up returns to its starting hu v( 0umemu5dd,,s3jq4pf9 apoint in 13 s. What is the initial speed ofmu(d qv5u jae34hm0u ,,9d fps the bullet?

  A ball is thrown straigk4aj m oky+p)2ht up with a speed of 36.0 m/s. How long does it take to return to ) +ajkok4y2mp its starting point?

  A ball is thrown downwar(hxu(w-wrd; id from the top of a building with an initial speed of 19 m/s. It strikes the ground after ir;hwu -((wxd 5.0 s. How high is the building?

  A ball is thrown straight up w.az 4zh9 cd/8ah q0ztx fxj*n4ith a speed of 30 m/s. (only fill in numerical value in the blfh 4h*dzz048az cxnajqt 9x/ .anks)
(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 s/ed1pi7* + ; s.,hu6itjpkf 6+ +valuuki qopitraight up into the air with a speed of 20.5 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 velfvt71pkh5 ; yh(i,kfd1i kg p:ocity at t = 1.0 s?

  In Fig. below, what isrix6,q69sbu f ,s ln mp/m*px:jugx:/ the velocity at t = 2.5 s?

  In Fig. below, what is thep hu2; vk7(tub velocity at t = 4.0 s?

  In Fig. below, what is the v ln/2)2sn/:gw dwxhg xia2)whelocity at t = 5.5 s?

  In Fig. below, what is th cdilubrb(05c:7mu cl*65jvx 9wti m+e average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity;qu70h d mrlc+ from 0 to 6.0 s?

  In Fig. below, what is themi9v3xk)cr:.ds , k lib (ie8o acceleration at 1.0 s?

  In Fig. below, what is the accelerations7eeo5 jo*c ;cr (x04x3oh fhq at 3.0 s?

  In Fig. below, what is the average accsw 0lvvcq90e+ eleration from 0 to 5.0 s?

  In Fig. below, what is the averageka tuv;; g6o)l acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to y6cmvb2 h v+kt5q n80a7z9oyd 8.0 s?

Does a car speedometer measure ctc5k-6xd 1 b g7sntrc1ob53ospeed, velocity? {speed|velocity}

  An object can have a varying speed if its velociw2 hrnog/8kf)ty is constant.

  The velocity of an object can be negative when 59g pajl(ypal;/yfx .its acceleration is positive.

  If one object has a greater speed than a seconde.tklcg:0 h; r4qw 3rb object, the first must have a greater acceregtq34l;0. cwkrh:bleration.

  Two cars emerge side :b) 4jf1 byc.beio q49sg0our by side from 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 g6j1b7emx0q - lil i6icb+vx4its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It bga, ; d;p7wszleaves the bat with a speed bz7dgsa p;; w,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(5ixrxpx p +*7vx/moc is happening to its acceleration, how does it7+ro vx(cp5x pmi */xx change if air friction is ignored?

  As a freely falling object speeds up, what is happening to it ye;.gbp/ hfmyd,hs (4s acceleration, how doeph gym;e(b,d .hy/fs4s it change if air friction CAN NOT be ignored?

  An object that is thrown verticall5nu8:zy ev*;9xl ,wawe) j icmy upward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how w nij,*5cwu: ;ly)e eavzxm98will this result be altered?

  An object can have zero velocity/3: dv+fetb8 kkwz2p5 kkez6x and nonzero acceleration at the same time.

  An object can have nonzero velg3+0js9pzos hocity and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor mgkki;v6 *yd3d zznp llv;i, z9a ,z--oaking no stops along the way has zero acceleratia*iozk;l,g6l;d-,3-9 y vizz n v dkpzon all the time.

  A rolling ball moves .d) olyg3 uof3from $x_1=2.2 \mathrm{~cm}$ to $x_2=-5.9 \mathrm{~cm}$ during the time from $t_1=2.3 \mathrm{~s}$ to $t_2=5.7 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.8 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.7 \mathrm{~s}$ is at $x_2=8.0 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight completef/cczvj)1cwm8ik.n - laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 10.1 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; o lo1 2;jtz+sj-a6ubz 1srd;2ztiwv straight line, moving 106 m away in 8.3 s. It then turns abruptly and gallops halfw121 ;arb j;;6o-tz ti+z2sjslvzdouway 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;9ywf:)xfe7k 1c jnb 8gv3c qi $12 \; m/s$ to $24 \; m/s$ 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 fro3) +wfz ruk+cnm $18 \; m/s$ to rest in a distance of 72 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed oi o wt3w8lbv)o y:)wuq8d9s0qf $25 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.4 \; m/s^2$ ?  (数值)  $m$

  A world-class sprintg9 x;a5 jdt4cter can burst out of the blocks to essentially top speed about td g9x4at ;5cj$11.3 \; m/s$ in the first 10.9 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 uniformlf b*sr; w fn69wrhoj+;y from a speed of $16 \; m/s$ to rest in 5.78 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 high,9r -.hft y;c*r i8e *fcqoawpway. Assuming a deceley f i8ro qwae-c,;9p.hf**ct rration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a tru i7q:ozb, /wiyck 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. Afrdv6q*9jm9wtjww (.2dkirq , ter exactly 27.0 min, there are still 1100 m to go. The runner must then acc9ri,qjwwkrtw (6dd q. v2m9*jelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$