Suppose that an object travels from oneq0 e kjp3pfh 2xa z/d4vh75ar* point in space to another. Make a comparison between the displa47* khpfvr2/530aq phd jxeza cement and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velocity?r uat*l :)uin)

  A new car manufacturer advertises that their car can go "from zero tozb)2axj x7z;i sixty in 8 s". This is a description72abij)zz x;x of

  An object moving in the +x axis experibq ap*gu 37x(d32suel ences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x directial0ud),c4 ud zon) begins to slow down as it approaches a traffic light. Make a statement concernu d)dc,z04aluing its acceleration.

  Suppose that a car traveling to the West (-bl 4ywi2h(1tvt6k1 da x direction) begins to slow down as it approaches a traffic ligaldy h 2 twt161(vkib4ht. Make a statement concerning its acceleration.

  Suppose that an object is movi boehai0u*stc(*o2-v23rhq6 kw u g hu2z0u5xng with a constant velocity. Make a statement concerning its ac05q ca2i2w 6ke(h3b*zuxgo u* 0h -sv2ouruthceleration.

  If the velocity of an object is zecm7 qrdb8kmg *kf ym*n) m0/*oro, does it mean that the acceleration is zero? Support your answer with qo brf**7m* )c8 nmdg/m0 kmkyan example.

  Can an object's velocity change direction when its acceleratixel m,8w iy+gmp9 *y 7mvfdkj,/5 / v1eiy+cpqon is constant? Support your answer witg9i7,wyqemekli +m//pv,*v+cy f 1p 8dxjy5 mh an example.

  Suppose that an object is moving with constant acceleration. Make a u 42x7hqzn,ys statement conce4n qhxs2y7,uzrning its motion with respect to time.

  Can an object have increasing speed while its acceleration issyttin 225-hbebca*g c7)u /g3w+ rmb decreasing? Support your answer-/gitu cbc5)37 y g+2bwsna2e r*hmtb with an example.

  Suppose a can, after an initial b2h0j h*kr 4cfieq0r/ kick, moves up along a smooth hill of ice. Make a statement concerni ckrjfhe0i4hqbr/*0 2ng its acceleration.

  Under what condition is *zyqtpo5,t08 hp mcs5zq1p1waverage velocity equal to the average of the object's initial and final q w5s1t zc pz8ym ,*qpto5h10pvelocity?

  Objects A and B both swou 97j6f p0aktart at rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final speed of object A compared to thf kauwp076o j9at of object B?

  Objects A and B both start from rest. They both accelerate at the savdmyv5 thuy+8k9z7 k i0 9zc0jme rate. However, object A accelerates dzzh+mv5kky78v yut0i90cj 9for 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 ancs7y;;bgyjkcbd2opgig3 +2 (a sz/y ,d falls in the absence of friction, which of the following is true concerning its motion?b+gyoz g7(d2sg p c/b3i2a; sk,;ycjy

  When an object is released from rest and falls in the absence of friction, which h7zddoux6d+ i3g31 h9z9*dqvtp 7jv+hgdh r2 of the following is true concerning its3hq26 opgx9 3*t+ uhjzddddhr9i7vd1h7g +vz motion?

  Suppose a ball is thrown straight up. Mro3 dkn-yrms:ij/mg e 2o)r44ake a statement about the velocity and the acceleration when the ball reaches thej3:4)mn-ye42 gkioo rsm r/dr highest point.

  Suppose a ball is thrown straight up. What is its ac*wxkn f 6hc; +2/f ot.y:6wnnmr;xh fhceleration just before it reaches its hig: +nnwhckn; ;hf6 x hfwr.2ym6x/ of*thest point?

  Suppose a ball is thc4d 53 ywq/h-v6kppci 4caf7z rown straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the veloci/3hwp k cpc4d6qz-5afi7cy4v ty and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to its i z(j0(qjqj 3bv im;2rhnitial height. Make a statement about the direction of the velocity and acceleration as the ball is coming jvq3j((b j2 m0ziqh;rdown.

  Suppose a ball is thrown down q,7 hy*u7zyfzward in the absence of air resistance. Make a statement concerning its aczhfq7uz ,7*y yceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her : 3b deovqdw-2uz,l.h acceleration when she she reaches termin:,bdl-ode3 zuq .whv2al velocity?

  A ball is thrown vertically upward with a speed v. 9exy ( *3fiieiAn 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? (Hif ey3*9iei( xow many times higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, ball B is :qzy hsg ,2y9f9t:bmndropped from the same building. As time progressmq 9:f,y92hyt ngbz :ses, the distance between them

  Ball A is dropped from the top of a building. One second later, 4 ,oa*-nhl*nbfdd, xqball B is dropped from the same building. As time progresses, the diffn o4n*d ,fq *hla,-dxberence in their speeds

  Two objects are thrown from the top of a tall building. One is thrown7qkm hko8*;yw4rub o u6td2g tux5r (8 up, and the other is thrown down, both with the same initial speed. What are their speeds whenqu8 5*htxur 8247 otbwokr; (umgyd6k they hit the street?

  A brick is dropped from the top of a buildi /b2th : qjzj:j,/e2ylq;k zmpng. A second brick is thrown straight down from the same building. They are released at th/:hjkze;pm: jl 2,qytb/jz q2e same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant nonu, z7ceul.*nm0ma z h,-zero velocity in the +x axis. The position versus time u7.0, h,l maeucmz*nz graph of this object is

  An object is moving with constant nong p++fzf g*.rkr9b-yg,*szxs-zero acceleration in the +x axis. The position versus time graph of this obj+b *g-p s9gr*. zfz ,xr+yksfgect is

  An object is moving with constant non-z )nd .nny0n3xg ,e em*te7m-akero velocity in the +x axis. The velocity versus time ggn,xd n). 3eamktenne* 07y-mraph of this object is

  An object is moving with constant non-zero accezcu qj2e5cx0t2t+- p h r5)zfyleration in the +x axis. The velocity versus time graph of this ozyc fp0cq jrzt25+xu-t)e2h5 bject is

  The slope of a position versus time graph u;-bblo7r v 37br; ieigives

  The slope of a velocity versus time graao2 tu wop5q z99y+,2i:n8 lmpp3rrydph gives

  The area under a curve in an acceleration versus time g+ect4c(g2sp txir1k * raph gives

  The area under a curve in a velocit/.-yazqe zx,-gu4jvh y versus time graph gives

  If the position versus time graph of an0j-s)pg-g:od: f f fbh object is a horizontal line, the object ish): bjff--psdfog: g0

  If the position versus time graph of an object is a vertical line, theit ,nh.p*me .hr m01xz object isz0 hm *htx,.e1p.rn mi

  If the velocity versus time graph of an object is a horizontal line, h k 2n4depugp 4z*p-e+(w pwk2the object ipg+pek(u4wehz pn *dk -224p ws

  If the velocity versus time graph of an object is a straight line making a,p pvd* 2b;m2cv94kfb xuuxp6n angle of 30 degrees with the time axis, the obpp9km2u4pxd*b c xu6v,;vfb2 ject is

  An object moves 15.0 m north and then 11.0 m south. Find both the dista sses * 93b /zb,nk+g+: vj3oeq5we;ocrnx9qfnce traveled and the magnitude of the displacee9kb3 o+rn /qx9 5,3f:j zs s+oevcgwes*b; qnment vector.

  A boat can move at 30 km/h in s(;sosu.i hl/w k y7i,rtill water. How long will it take to move 12 km upstream in a river flowing 6.0 km/hhri( so klusyi,/;w .7?

  55 mi/h is how many m/s? (1 hzgl .uk5 g5znff),o-mi = 1609 m)

  What must be your average speed i.zhkd 1k4cw ,wn order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. Wd:l7dan vd,1 that is the average ,dv:td na7dl1 speed of the runner in m/s?

  A car travels 90 km/h. How lgn,ba mx upu+/hiz ;yydc10.: ong does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one year. The speed +j8jv uc7nhonlxm*5m p-j7w ighr7; + of light is p775ohjjw+ jxnrimmu+v 8l -cg;h*7n$3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 72 km/h along a straight road and you look to the side for z;h8u(6lkvw/ mm 4evy. 0.myclj8kyd 4.0 s, how far do you travel durin/clvj yd 6h0e8m (yuy.m8kwk4 v; mzl.g this inattentive period?

  If you run a complete loop around an outdoor track (4v/ p,tw hqhe6800 m), in 100 s, your average veloct,6qwhev8/ hp ity is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km a6r xia7 2 mxo/ oo*hs74dqcn/east, then 1.0 km nc 77d6h x xs o2aooimrqn/*/a4orth, 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 Pole. It travels8-jjzho7 /wuu 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 tak/j uh8joz-7wues 45 min. What was the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles.c3exlms(87h 1 xraa ; b-.dmjn It then starts to snow and you slow to 35 mi/h. You arrive home afte 8lb7axd3r ;-xsncm ah 1e.(mjr 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 10l 4ghhr4+b5oikyb(k; 3jmyo70 km/h. What is the average speed4h7y r3b + (okkjgi4oyb5hm;l of the motorist for this trip?

  A motorist travels for 3.0 h at 1,p-aa ez6hjl80 km/h and 2.0 h at 100 km/h. What is her average speed for eh, p1l6j z-aathe trip?

  An airplane travels at 300 mfh dl -a4*-an3ywhiu6i/h south for 2.00 h and then at 250 mi/h north for 750 miles. What is the average speed for the trip?-6* dyh4a uhafl-wni3

  In a 400-m relay race the anchorman (the person who runs t8 7dfchn;8)v5p vhxlnqo p1 u0he 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 d78fxop1u 05l8 ; cv nnqhphv)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 after 12 s. The car's 3vuu7zt+hcp9rz - m /eaverage velocity during deceleration was 72 k9het3upc-u 7/rz m+v zm/h. What was the car's deceleration while slowing down?

  An airplane increases itq1kc 7f7yvcwrx11 x/fs speed from 100 m/s to 160 m/s, at the average rate of 11wx1cyf q/c7v 7rfxk$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h 9:wmwwvrbw ).d f 1vx-accelerates 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 accelexp/ hmnidpso nk: 6pn;:sq+2n (p1 p)mvquy9.rates 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 consta edus f 3j+0 *bk5-5cmwyq2mz0rghrt*nt acceleration zu2 3wydjt * 5 hsrkc0g mfbr+e0*-m5qof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocit01ny c9:nn, *(o bougdpzbrp;lo7b6 gy of 1.1 m/s experiences a constant acceleration or7b 1ng up(,oo;*6:lndpgc obz0ny9 b f $4.2 \; m/s^2$. What is the cart's displacement during the first 5.0 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of 53; 0 gojk72cevym 1xrz70 m/s strikes a sandbag and penetrates a mzye;ov1x32g 7cj k0rdistance of 52.39 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapulu e0pf -l7,dlcl7 j.u4xqw c f(dw:yn)t 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 co jd4 fdc ,wll70xuf:cpy(qul.-n7)e wnstant, what is the length of the catapult?

  A car starting from rest moves with consta)jeqna m2lk7(.l 4vl ant 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 distanc +:5uklrnjo r.kx;9mme of 200 m. What is its average acceleration9molxrk. j+k :;um5rn ?

  An object starts from rest and un8g z().r co x;r2kcggkdergoes uniform acceleration. During the first seco.z rgxkc(;)2grcg o8knd it travels 8.0 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initially.xicqfjxqsyoazd5is yu 895 y, )9z96 it is traveling at 16 m/s. Three seconds later it is traveling a.y 9uoafzx58i)5y, 9djcs y xi6qzq9s t 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates u2t 4yjd7 jin7rniformly 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 roadp9,,5arij/ p qkykw 9h 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 6v.g t04m: gmt*z9qq f,hr2sp2llyjz that has been waiting at the intersection starts ahead with a constant 26 j2 vhyp m*tl. qgzlg9zm,0 ft:4qrsacceleration 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 speed2 (ekyi)ay1 aypy+ bt) of 12 m/s on the surface of planet X where the acceleration due to y21a y (i+)y)kpeaytb gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed ou;9vb6i 8d1qql9 5pht ah-lxy 0d6dd hf 12 m/s on the surface of planet X where th1 5h- 9dx8d;d9a hvlut ibh6qd0lypq6e 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 0 7h2) tjomerpfe8)uiupward with a speed of 15 m/s on the surface of planet X where p8e7r h02)ofm)ituej the 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 16 jex3mo t lpq3f(rz::4 m/s on the surface of planet X where the acceleration due :o qtf:3lemz x j63(rpto 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. I :2u s k7iqy.jr/gipk/f your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fall befojpq s7k/k iyg:/ 2.ruire you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its n8m8h lvd:vqou)5s)o m8,my ovelocity after 3.0dnm:)u5vm 8o8 y8hovm qsol),0 s?

  A bullet shot straight up returns to its starting point in 6 s. What is the inid 9ngk-5btxshd 0:4uh tial speed of the bullet?h k:9 0sx4 d-g5dhnubt

  A ball is thrown straight up witqk3pu t u-ob94h a speed of 36.0 m/s. How long does it take to return to its4 put9 uq-bok3 starting point?

  A ball is thrown downward from the top of a+qyz,8 qfpx q;4 -rkd4f5inek building with an initial speed of 18 m/s. It rpy,+xz;ef-kq ifq kn8q454dstrikes the ground after 4.9 s. How high is the building?

  A ball is thrown str e0.hi irg2o/faight up with a speed of 30 m/s. (only fill in numerical value.0g/rie ohi2 f in 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 up into the air with a speed of 41.7 mk5sf7fg2d/ g; 3n*xtb .t5ws ,zxtpnc/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 15 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 15.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the v3-fjd+i +xk7k rpxmwsif x i)-: v5/onelocity at t = 1.0 s?

  In Fig. below, what iy /5blc*,qb.l.ibt xks the velocity at t = 2.5 s?

  In Fig. below, what is the c;kuy)a5h,;yf pp tn./c g:oo1ev u: uud-1rwvelocity at t = 4.0 s?

  In Fig. below, what is the velocity at t = go3 m7b puw-5ju k4bs(5.5 s?

  In Fig. below, what is the avervm m,08rb o0mz1y7 vhzage velocity from 0 to 4.0 s?

  In Fig. below, what is hag:yts7m9k - the average velocity from 0 to 6.0 s?

  In Fig. below, what is the accelerationw7 0x7rk 753arjc61ei bpv gbu at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 .s j; j8ne 6;5uaq,v2cio*hb8v cpuzos?

  In Fig. below, what is the average accelerationmgixq k fzi7)e: iwtol,/or;oxc .)60 from 0 to 5.0 s?

  In Fig. below, what is the average acceleration f :fhy0t lcy(.rk xa(1xg3r7zr rom 0 to 8.0 s?

  In Fig. below, what is twn.xq3udj-+xzpk)t ; he displacement from 0 to 8.0 s?

Does a car speedometer measure sp6cawg* q iqp9rteere *: 1n-6zeed, velocity? {speed|velocity}

  An object can have a varying speed if tzpj f:1kfb 8g+y(p: mits velocity is constant.

  The velocity of an object can be negative whenn67+mo(p m*q.zlswsp its acceleration is positive.

  If one object has a greater speed than a second object :cpaawfq) k9 g8dr))s, the first must have a greater acceler)aaqrpc8sg9 )k wdf): ation.

  Two cars emerge side by side tfbemh;8su ql o, ;3b) v,o.i/ljxc)zs1ur;m 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 its acceleration decre. l cu0 z3r/n62x yzi,v4nurfiases.

  A baseball player hits a foul ball straik jpd +dgg-6g2ght up into the air. It leaves the bat with a speed ogjk- 6 ggdpd+2f $120 \; km/h$. 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 objetsf1yd mkmd.*8sre : 2ct speeds up, what is happening to its acceleration, how does itm*1 e dry.fk82: dtmss change if air friction is ignored?

  As a freely falling object sgls0ehwiwb2* tk9 kj*g ,ev.e lr/hxe:u +n7+peeds up, what is happening to its acceleration, how does itwh+ehbg ei*ekgnk92,0t l7*u:.j lv s e+wrx/ change if air friction CAN NOT be ignored?

  An object that is thrown vertically upward will return to its original position jc ulji3ll2q78 g4f 0cwith the same speed as it had initially if air resistance is negligible. If air resistanlc ql8l3fig4j2 0 uj7cce is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration at the same t dn1/ ovvlhe+z c8v/h*ime.

  An object can have nonzero velocity and zero acceleration at the s 0syk / .zbia/t/, ,hxjvue;vqame time.

  An elevator moving from the second floor to theck mpi wscfynnx,x6*: 8:4o3b fifth floor making no stops alon 8o64xm:xs*: fwki3pcy bn ,cng the way has zero acceleration all the time.

  A rolling ball moveshwog36k/a2bj from $x_1=2.5 \mathrm{~cm}$ to $x_2=-6.1 \mathrm{~cm}$ during the time from $t_1=1.9 \mathrm{~s}$ 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 $t_1=-4.9 \mathrm{~s}$ is at $x_1=2.0 \mathrm{~cm}$ and at $t_2=3.9 \mathrm{~s}$ is at $x_2=8.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a qu*dr3y 2fe*c d:eaj1+h 7zxyrdxr t1o8arter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.7 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, moving4+-se9 oagjsx 94 m away in 10.1 s. It then turns abruptly and gallops halfway back in 4se+ og as-9xj4.7 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 -a2(vmg5dy nc$13 \; m/s$ to $24 \; m/s$ in 4.5 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 s9)l))tiqyui: fyjcj5 3m5s m$17 \; m/s$ to rest in a distance of 57 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must rfgq:; yr- 3o.f 2f knp1sdk)zxeach a speed of $29 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.3 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to esspe,x:i h3bi8tl,7x ud/n 1 segentially top speed about ,dn, e t183 7p:/ehxiluxbigs$10.7 \; m/s$ in the first 12.0 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 unifor-o 5jo hju)v:spa (k-imly from a speed of $17 \; m/s$ to rest in 4.93 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m long on the highway. Assumivvl v2-t ukeu6z//oab17w 6xsv58b eang a d7 12bx6wvo- u/zkvlbvvua6e5te s8/a eceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goh.fxack8 juj -4b(.nq ing $25 \; m/s$ 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 xew;t4c(/tfwf/ *l n 3 to/tudviqo) *the 10,000-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The wo/ * */q3lwd;txfntoie u)v /(4cfttrunner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$