Suppose that an object travels fromtm.y -(.yo wnqog5i;q one point in space to another. Make a comparison between the displacement and the distance tr oyqq;tog..y5 n (-wimaveled.

  When is the average velocity of an object equal to t3gzvhi( en2eav5rac.kw1. s5he instantaneous velocity?

  A new car manufacturer adverti nk:)+u v9lqjases that their car can go "from zero to sixty in 8 s"+jul9vk :aqn) . This is a description of

  An object moving in the +x a t.bb;(n8p 7b t(g,mkhuvimn8xis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (( kt:uv*0+8 . qbehz uoxes+fc+x direction) begins to slow down as it approaches a traffic lightuuz*s efxo0 .qve8 :h+(+ctkb . Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to sl4xm t x;z*d .go)tzcoht y3t71ow down as it approaches a traffic light. Make a statt3todo1tg.y x7z x * ;tm4)chzement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a sfkuw a- 90l.rytatement concerning iklry9w .a-0 futs acceleration.

  If the velocity of an object is zero, do( ln b6;nkum3+4q+i w nq-+notne*qnees it mean that the acceleration is zero? ql4u-i+ +nwent on;*q n b(nnm kq6e3+ Support your answer with an example.

  Can an object's velocity change direction uy) dt l91g,;+(bkrt,iwopzdwhen its acceleration is constant? Support your answer brtyd( ;ud kp,i9)tgl+z w,1owith an example.

  Suppose that an object is moving with constant acceler*e4 igxe0qzh 7ation. Make a statement concerning its motion with respect to time.0ixeq7h 4ze g*

  Can an object have increasing speed while its acceleration is decreas8;18rk z-; cwog zzb,dvbmc;xing? Support your answe ,xgcr;wmzo; -1; zzbbdkv88c r with an example.

  Suppose a can, after an initial k-g n/nm 000r)iw wyxagick, moves up along a smooth hill of ice. Make a statement concerning its acca0-iw0ynrm)n / wxg 0geleration.

  Under what condition is averaged (hs0f 7vnbkg.a/ow8lz e)gg5g 6mha63 mgw; velocity equal to the average of the object's initial and final v)/eg (oab.3w6l7 va; hw zgndm0ksfgghm6 g85elocity?

  Objects A and B both start at rest. They both accelerateqvqb0x t9-g+j hs)5vs;,eado at the same rate. However,vj9-b g;a e q+d5,xvsqt)0osh object A accelerates 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 r alw20cqf/gy: ate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared to that of object Bg2lq f :w0yc/a?

  When an object is released from rest and faq4hh1 +o;idy lp z573 hbl.rjclls in the absence of friction, which of the following is true concerni4h qbrdh5 yz;hc .i1lo3lp +j7ng its motion?

  When an object is released from rest and falls in the absence of friction, wk l mp*p*eix :ldq+mp dj494a+hich of the following 9xpi*d *l+ jed q4:l4ap+pmmkis true concerning its motion?

  Suppose a ball is thrown straight utz8bqa, 69)3 ng-ehi c pepy.fle6a70garhz1p. Make a statement about the velocity and the acceleration whene6 n8a,t7-fb)69 pycgqz3z laae.1 hrghi0p e the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before it r0ye*b0k (dz .m39)mthficjt beaches its highest po(e kdjczmm*9i ytfh0.bt)3b0 int?

  Suppose a ball is thrown straight up, reaches a maximum height, then fala q1and8/r7pa.3 r*ozo9;x4.i effx b4dzjcg ls to its initial height. Make a statement about the direction of the velocityb4o q enx dg.prfo/z4 z rad;f8.x c379aaj*1i and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then3sg+ *hfk -o9b*qna sc falls to its initial height. Make a statement about the direction of the velocity and acceleration as then39sb hgac*osq*fk + - ball is coming down.

  Suppose a ball is thrown do2 mn3p *jp4yd(lo,;papzbk*xwnward in the absence of air resistance. Make a statement concerni z*p*k(4 abyp3p2;j mpdn l,xong its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her accelerati k p1 f:c 49m((xp5+7lhuddy0efsnmwnon when she she reachesfx: ((ls 057ypmhd+epk4fn mwdu1nc9 terminal velocity?

  A ball is thrown vertically upward with a speed v. Avd 21a*jf8y xxn identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of tx 12yaxvj 8df*he 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 fro nv9nf4 qvf:afgbb8dg9d d*( 5f t9dj.m the top of a building. One second later, ball B is droppeq(nfvb v59f afdgj9 4 :nd8ftgd *9.bdd from the same building. As time progresses, the distance between them

  Ball A is dropped from the top of a buildingbgjvfi 6wgp7k4e- t/q4no1w0 *0ics 83bwpra. One second later, ball B is dropped from the same building. As time progresses, the diffeig fe-nok47b*j68w3qr/p4 vswgc pt0 b10a iw rence in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, an db7 uf5yib-onel8z) 0d the other is thrown down, both with the same initial speed. What are their spee ed 80f5oiz -)b7nyulbds when they hit the street?

  A brick is dropped from the top of a building c(owrce 7kj(2. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Comparek 2 (cejc7(row the accelerations of the two bricks.

  An object is moving with constant /z rl6vml+4gm non-zero velocity in the +x axis. The position ver m4 r/lg+mvl6zsus time graph of this object is

  An object is moving wim zql5d: zief-:iiu82pr bz,4 (ahb8ath constant non-zero acceleration in the +x axis. The positlrpq5 fa2z b :adiiu4:,(8hb8-zz ei mion versus time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis)kcsz*ts1 sgtds ton,huc (/-9i(m3,)judvm . The velocity versus zku */dj s,m)vgu(c1 io9c(3s)stt,n th-msdtime graph of this object is

  An object is moving with constant non-zero accele( 8-vlws+aqq7 njoes/ration in the +x axis. The velocity versus time graph of this objej(-wo n/sq7qsve8l a +ct is

  The slope of a positioq8-nqulqz)97) zlep y n versus time graph gives

  The slope of a velocity vn, wh*my; 6tj;c5( ar:*gkzp . 0grkthkiz9e kersus time graph gives

  The area under a curve in an acceleration versus time g3qw,vckj 3 nvw)n d/3yraph gives

  The area under a curve 4doq, s j5imp3+nufa8in a velocity versus time graph gives

  If the position versus time graph of an object is a horizontalwxy4 ;*cy enx472cdnc line, the object ncx4*4dc7wxcy;n2 e yis

  If the position versus time graph of an object is a vertical li xbhpov nfl) bteb(9-1aqbirw+13o: 9 ne, the object is3vpeba-o9bb l1fw +i1tb(:qr h)onx9

  If the velocity versus time graph of g heo-l-amd5p((bv w:an object is a horizontal line, the object ieblo(m a:d (wh- pg5v-s

  If the velocity versus time graph of an +4ff4eo1z xlwco0n 7rmzc x2 k(x e8b/object is a straight line making an angle of 30 degrees with the time axis, the f74zxn(2zeowoklm/c 1+fxb8er0c 4x object is

  An object moves 15.0 m north and then 11.0 m spmqii*zcs g ayn *g6pw+8g; )/outh. Find both the distance traveled and the magnitude of the disg)g/pyqc*niap6s;*m+ w8zig placement vector.

  A boat can move at 30 km/h in st l gimzeypjwt8 :u(1,+ill water. How long will it take to move 12 km upstream in a river (e mpywtlji,u+1:z 8gflowing 6.0 km/h?

  55 mi/h is how many m4+ )9ein )lkdnd;pejh /s? (1 mi = 1609 m)

  What must be your average speed inx6zw/() any xh order to travel 350 km in 5.15 h?

  A runner ran the marathon (app-nnz od5 1maolbx9c -;f :jho/roximately 42.0 km) in 2 hours and 57 min. What is the average speed of the runner in m/-xonaom zo/ 95lf :-b; 1hjcdns?

  A car travels 90 km/h. How long d4v-gu yxdk(,: m1yhbooes it take for it to travel 400 km?

  A ly (light year) is the distance that light travelsicesn 1ck8*c 5 in one year. The speed of light iic*c sne85kc1s $3.00 \times 10^8 \; m/s$. 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 strunedjkhy q;/6q33euv 7;is :xaight road and you look to the side for 4.0 s, how far do you t6h3nq:; e kd7/ ys;j3ieuu xvqravel during this inattentive period?

  If you run a complete lo y,53dwvvcex* op around an outdoor track (400 m), in 100 s, your average velocity *ex 5vcydw3,v is

  A polar bear starts at the North Pole. It travels tbl7l qqv,s, 51.0 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's avblqt , s5v7,lqerage speed?

  A polar bear starts at the North Pole. ; ;rl,lu,wypuyl7y 2uIt travels 1.0 km south, then 1.0 km east, then 1.0 km north, 2ypwl7yu; yl ;,lruu,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 weekhhb*-0rerx5,sr so9jend from school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home after drxh 09sre*so ,h-jr5briving 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/h. What ilvof07v1 j8p/ soa4g xs the average speed of the ml 0o /g7x1pjv4ovfsa8otorist for this trip?

  A motorist travels for 3.0 h atjx zv;s** /a e3zxgq.s 80 km/h and 2.0 h at 100 km/h. What is her average speed for the .gx3zs *;s* qz/ejaxvtrip?

  An airplane travels at 300 mi/h south for 2.00wkfdp:kz*/6-onw c)* aewzozts 63f 2 h and then at 250 mi/h north for 750 miles. What is the average speed for -t/fd2 a6*kcfww)*np zwo sezoz: 6k 3the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for5 eqq 0iyflbprmf -p 3ekm/sjbd-+ ./4 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 that the tee4 / p+i-jsmeyrfk/m5bq l.q03-dpf bam A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 9 s. The car's average v(g eg+4 wei,nqelocity during deceleration was 62 km/hi gw4nq (e,+ge. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s e-(a(1 0hi rzc8vslc.yc xn:f, at the average rate of .x8 ne( (l cy:c0- saifchv1zr$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the ratef c,/va7xi vn8 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 accelph ei847t4b4dw pspp 0erates at $4.0 \; m/s^2$ for 5.0 s, then maintain that velocity for 10 s, and then decelerates at the rate of $2.0 \; m/s^2$ for 4.0 s. What is the final speed of the car?

  A car travels at 15 m/s for 10 s. It then speeds up with a consta5u37nquoy//gs g5xh 2dv+9qq sn 4p xlgx 1ov9nt acceleration oo sy o d/gg+5xqv97px12 5lxg9/uhvs qnq4n3u f $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity 2b xu 5/-j0 c+epvtcwbof 3.3 m/s experiences a constant acceleration otp 20w bubjecx5c/ -+vf $1.5 \; m/s^2$. What is the cart's displacement during the first 4.6 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of 247 /dwua88dwz md 8ik*z,m/s strikes a sandbag and penetrates a distance of 43.86 cm. What is the aver zdw*8 kz8 8ud/wi,mdaage acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a cawj,b.r da ;f;z.t8npw tapult on an aircraft 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 consra;fj.ww;ptz. , 8n dbtant, what is the length of the catapult?

  A car starting from rest moves with cof3w4z90 k:ef t* abl7xwysd17 p2iwjq nstant 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 menvr5 m .;j6iaoras25/s in a distance of 200 m. What is its average acceleratioemo;a.s2r5r nj iva 56n?

  An object starts from rest and undergoes uniform accs1 +ntm 6edim,eleration. During the first second it travn,me+t1msd6 i els 7.8 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Inity epebnu pb3r 7hhz6up-3gc+ji/+06yially it is traveling at 16 m/s. Three sy u7nr ip/h+ygebjhupb6+0 3-zc 36epeconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accel5sz79lu7fsnbx(1kbdl :bim * i27frd+ mx oe1erates 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 jf8i;l ( +hox04; le;ui jzntacan 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 cap7 /du-9-ksvsb6hu xz10a ntor that has been waiting at the intersection starts ahead with a constant acceleration of /9 ohb-zu1dsknuvs6 a7-0pt x$2.00 \; m/s^2$. 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 upwa-8ztvnwq m ;9 31a;9ucwqnmxhtk (mj;rd with a speed of 12 m/s on the surface of planet X where the acceleration due to gr v ;3(nxnm8;u9j9 ;-mktaw h zqwtmqc1avity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speewxr3;xop h4c8artpm / l))h1r d of 12 m/s on the surface of planet X where the acceleratiorhorxtwm )pca4;1 )h3r8x /p ln 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 of 15 m/s on the su m ky:n.uu;nhv+1fp) qrface of planet X where the v;nh k1:nf)yupq+m. uacceleration 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 surface 6q-qd3u(kz gsof planet X where the acc-gzdskq(qu3 6 eleration 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 g5 kmz:s3hq aw)40nio0.10 s. If your friend holds a ruler between your fingers anza4ws0on:m)3 qkh5 ig d releases it without warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its velocity after 3 ,8dfciwg/6qj / cjdi q6wg8f,.00 s?

  A bullet shot straight up returns to its starting point in 12 s. What is the 0y+g x+5q29,sjizt*nrdj dbwinigbd s ,5++*njyiz092rtx jdwqtial speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How c6z840s x9-;yieg v a 5niv50rugxfz:iwrx5mlong does it take to return to its fzrmei;6yz:aw u8s 0gx-irxv 9g5n0xcv 4i5 5starting point?

  A ball is thrown downward 9z/r0ymkfmd6cx+ 3j 1 p3tz dbfrom the top of a building with an initial speed of 11 m/s. It strikes the ground after 4.1 s. How high is the buildzby0 tdkd3crj9mp/+f 31 6m zxing?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numericalk:ry5p0y.;wlu wwrtbo:y0h 4 e k 3z/q value in the blanks0.yk kr; wbu 5y0e:y4pw:wrot3q zhl/)
(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 wiubgpq.5l d*f 9th a speed of 28.1 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 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 veloc1 dz9 6 du1dyw6 avh-2t;gwttwr9dgh)ity at t = 1.0 s?

  In Fig. below, what is the velocp go- s,dx*pfqr0 jihk b4v y6d/)sac6t6u.9oity at t = 2.5 s?

  In Fig. below, what is the p wt he4vo*l/o -g.u.evelocity at t = 4.0 s?

  In Fig. below, what is seyy z0wu3 j+2l4ig2hthe velocity at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to 4.-cdr +uykz fnc h1;;jdao 5i*70 s?

  In Fig. below, what is the bsbfzv.v/ (m .average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration at 1.0.b 59zsis z0sgvja/q : s?

  In Fig. below, what is the acceleration ,qa7; r++m eh:hrdrmnon2y u3 at 3.0 s?

  In Fig. below, what is the aver *ov ,grpy:m7 vfx8b 5k/aob 3fa6bg,eage acceleration from 0 to 5.0 s?

  In Fig. below, what is the average accxq)g+ u 5uk+vs(dce6j: cu9dgeleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to e boweh7 zik)7(* 6xcx8.0 s?

Does a car speedometer measure speed, velo8xhtsy6 51yv5 fd; aw64kujjxcity? {speed|velocity}

  An object can have a varying speed if itugljca ,dtcyhq6:;bz7tl 39 ilj 4/,ts velocity is constant.

  The velocity of an object can be negative when its is7gd-0dn v(i (rzx)zacceleration is positive.

  If one object has a greater speed than a second object, the first7789xe.rtgb vufq)zf must have a greater acceletbq 89 e).z xffru77vgration.

  Two cars emerge side by side from a tunnel. Car A is traveling with a speed oy2 3w y8 d9 e:o2xxnr57pideihf $60 \; km/h$ 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 sp iw/(jaty2f/zh-i qa.eed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air x,j on.(khvbb 3v4k1a. It leaves the bat with a ,hn3x jo1.vkb (bkva 4speed 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 accelerat7, z4c.iajvmi ion, how does it change iazm4 .,v7ijcif air friction is ignored?

  As a freely falling object speeds up, wh6sjoje q47,zz at is happening to its acceleration, how does it change if air friction ,j qzo4z7es6 jCAN NOT be ignored?

  An object that is thrown vertically upward will return tos .vqkv bw-; pc+9mwv, its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be altepv.qsvcmkw w,; v-+ b9red?

  An object can have zero velocity and nonzero acceleration atifat53gh(k/ e the same time.

  An object can have nonzero velocity and zero acceleration at the same timep)(hjp/ ur(za g++igf+1 ckle2/v :kjm0bzvx .

  An elevator moving from the seconcmig(;* /3xt )ukr/:prdzcs ad floor to the fifth floor making no stops along the way has zero acudx)szam: /p3ccg* kr;r(/ti celeration all the time.

  A rolling ball moves frox-fw*ejix*0z ek0 / k8bwret *m $x_1=2.3 \mathrm{~cm}$ to $x_2=-7.6 \mathrm{~cm}$ during the time from $t_1=1.6 \mathrm{~s}$ to $t_2=5.8 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.8 \mathrm{~s}$ is at $x_1=3.2 \mathrm{~cm}$ 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 comple rrlapi*vd4 :;te laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 9.6 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its trainer in a straight line, moving 90 m away in n7ynj50z)es fyxs5us dsr50f;7 efg) 12.5 s. It then turns abruptny xee)5sn7fy;50 u jg s d5ssrf7z)f0ly 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 frolqw9 nu 2+oxg8m $12 \; m/s$ to $24 \; m/s$ in 4.7 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 fromq;z+( u(er)h fucid2xe i)hs3 $16 \; m/s$ to rest in a distance of 74 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must rv9p i7xa ld;b t4,t6e/e6il wseach a speed of $31 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.9 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burstq;r4v:,6wa 5abw5 gecp 7m 0hmx,o*tsjtl 8qo out of the blocks to essentially top speed abouttthv7wp 5, j brm5*xc40:wg8oa ;osmqae6,lq $10.2 \; m/s$ in the first 11.6 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 uniforw(u+(+tms l 9zz+w vajmly from a speed of $21 \; m/s$ to rest in 5.15 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 highwa* r2 33f71myf 0)fqqfqcshbo oy. Assuming a deceleratio of2q 0f hcys)f37*b3m oqr1qfn of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck:bzp4i.w /xqq4yqi( mw1iar :+zo mw, 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).    $m$