Suppose that an object t0bj he m(:3qmmravels from one point in space to another. Make a comparison bemeb0 (q mjm:h3tween the displacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velocitduk4:8fbr4u3x9 x sycej2o 6oy?

  A new car manufacturer advertises that their car can go "from zero to8o tb sy3,m7yoj; zv6g sixty in 8 s". This is a desby3o 68zvjs, ogm 7t;ycription of

  An object moving in the +x axis experiences an acceleraef)uxt5yjg q u4x:9k ,tion of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to /bo- wrm 5bno1r/ez3i the East (+x direction) begins to slow down as it approamren /z3 r-1oo5w/ibbches a traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x( -msqdt:vjf, direction) begins to slow down as it approaches a traffic light. Make a statement concerning its :qs(-, tdvfm jacceleration.

  Suppose that an object is moving with a c; -vr1o/xz, jkci;6u ybu qo6sonstant velocity. Make a statement concerning itsko6 /xc-qoy;sj1u z;uir6v,b acceleration.

  If the velocity of an object is zero, does it zq u5 3oo5t*h2zda+lvgy,zp2 mean that the acceleration is zero? Support your answer withq*zvghta 2u3lz5d ,+z25py o o an example.

  Can an object's velocity change direction when its acceleration is constavkgy9wyh9 x/j+64fisen;k/9gmj c6c nt? Support your answer with a ihn9ejsm6 v9ck/gj;g+ /kwf4xcy69yn example.

  Suppose that an object is moving with constant acceleration. Make*,cbr , k3m.nt;f8(saxjnl8t alaui 5 a statement concerning its motion with respect. k inc 8s(luj,35a8*x;fmrl,a abntt to time.

  Can an object have increasing speed while its acceleration is decrw.gcrpy esrwg;r o 2 b/9.+sam1i y2q8easing? Support your answer wim2ps r 2w;a9orri +wg8 ys.c/ygbe.1qth an example.

  Suppose a can, after an initial kick, f7nn0su.v(*52 l ab e*cz.mjsvcbb-pmoves up along a smooth hill of ice. Make a statement concerning its accelerau*bvn-s..b7j f(epcnvzba s 02l*c 5mtion.

  Under what condition is average velocnw- l4t5e: yc8n ij:v /qy oknzsld. bsg-d4.6ity equal to the average of the object's initial and final velocity?lsn4bw45vd:-y. z86.dqnseltc -kio / nyg :j

  Objects A and B both start at rest. They both acceleratm4vc x+/kors pvl n2m.9kk7e846al ii e 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 that of 8+v.c4k7nm4ela9 k/i6v kl2op srmx iobject B?

  Objects A and B both star/gu 7ok*c ly8mt from rest. They both accelerate at the same rate. However, object A accelerates for twice g78kl*/mcy u othe 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 and falls in the absence of frictirwbv-u o(7.uvt5k /gbon, which of the following is true concerning /vv .wg kbou 7(rt5ub-its motion?

  When an object is released fromocvm llxywfs 4nn9 .y*89a ),d rest and falls in the absence of friction, which of the followinglny4.cmyxa f vo8*,wsdn9)9l is true concerning its motion?

  Suppose a ball is thrown straight up. Mqyyt1 zj0 ;tx yh8:aoy5o2ne;ake a statement about the velocity and the acceleraty o;yqa tj:;x8o yth 1z0nye25ion when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before it awf6uw cbl+:5 reaches iaf+w6wl c5:u bts highest point?

  Suppose a ball is throwy6x*-8kg5.w2dds ff u ov(pgbn straight up, reaches a maximum height, then falls to its initial hexkf *yd.gsv6 2fdb5gu-ow 8(pight. Make 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 height, then falls to its initi emn cj;hicsi*, k5*8mal height m*mesh58k*j in; ,icc. Make a 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. Make4q zm5p(3 v7ar5nucvh z7c rqp (h(:nb a statement concer qhmrc z3 (5(nn(:ucv4b q7 h57vppazrning its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her acc 094bmpx*d 6a+xsid jjeleration when she she reaches ter 0xj d+mjpa6bd 9xi4s*minal velocity?

  A ball is thrown vertically upward with a speed v. An identic-01)l xbeish1z gep4zal second ball is thrown upward with a speed 2v (twice as fast). What is the el0p4h1xz -ib e)zgs 1ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a bui l1sfzssq16j;t c s.e*lding. One second later, ball B is dropped from the same building. As time prt.qf11zesl;6ssc js* ogresses, the distance between them

  Ball A is dropped from t(.ptep 7wb4 ag7bskk4 he top of a building. One second later, ball B is dropped from wkb g47et(p7 kba4ps. the same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, anv18 wzr.0 gayju drx).d the other is thrown down, both with the same initial speed. What are their speeds when they hit td 8)xjvy zwr 1u..rg0ahe street?

  A brick is dropped from the top of a bu+e../25twjxy6zr)v uwazxv i ilding. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistancewrwtvjz /xu aiy26 .+xz)e v.5. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The po)nzj ;yeb* )xxx+z0/mvpue 7i sition versus time graph of this object is upxvn;)ejy* )i0zb+ mzex7/x

  An object is moving with constant non-zero acceleration in the +x axm,nlqmw. w)ht*o. :d his. The position versus time w. mdwtolmh: n)q,. *hgraph of this object is

  An object is moving with constant non-zero velocity in the +x axis. The ve8zw e rztl exc1dh )3u 7*zk.y306xdy1jtg 5oylocity versus time graph ozd 7ewkoy hec*uyt6j)g x 1l8t5z1 .33yxzr 0df this object is

  An object is moving with constant non-zero acceleration in the +x axis. Th iv+p8)gs 1lj nz,w j6jd,wec.e velocity versus time graph of this object)8 g6dwisjejvwn.cz l1+, ,pj is

  The slope of a positqt4oxu x z/0277m0bniql egq3 ion versus time graph gives

  The slope of a velocity t4wut t2c9e.y versus time graph gives

  The area under a curve in an acceleration versus tnkhxxpt j s5))*yu0mjd0zowl* 5gi93ime graph gives

  The area under a curve in afpbcg0ze( m 5rpu* v3j,jt x16 velocity versus time graph gives

  If the position versus time graph of an object is a horizontal line, the object s4b f)uf ,.z k2wnms9w+zr6hbimfk+2 s uzw s6zbhw)9.bn ,4rfs

  If the position versus time graph of an object is a vertical line, the obrcg-ng 0gmn 6ae1c: rn vi.9h.ject ise : hggmna.1cr9r 6v0n.ig- cn

  If the velocity versus time graph of an object is a horizontal line, theqsu3i nu0hes j+1nr 46 object irq 4nuns i3s0eu+j6 h1s

  If the velocity versus time graph of an obj:4)e4ic9 f+czf ltkeb ect is a straight line making an angle of 30 degree:ctf )4k+c4zfe9el ibs with the time axis, the object is

  An object moves 15.0 m north and the0,zgw2 a 4m wcx24pooon 11.0 m south. Find both the distance traveled and the mazc4 xowom20 po2w g4,agnitude of the displacement vector.

  A boat can move at 30 km/h in still c a /e;arb2kzbsj2fr2ynv ) 1c0o7rl2water. How long will it take to move 12 km upstre/ebjc7 kl202 zar)vc2af1y 2r;sbrnoam in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1er z5fae /d0p8609 m)

  What must be your average speed in order to travelcf ug.ygqmirj r)1 / en+ni):7 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in. k acb 3et8m5b-1bj hoqll.z0 f9wo9c 2 hours and 57 min. What is the ave.mzch13- l5j9t0efo c 98qbako w lb.brage speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to tra6es,p-lbn/l lh.wy / lvel 400 km?

  A ly (light year) is the distance that light travels i ak.ck /ut/9xhn one year. The speed of lit/a 9.kuxkh/ cght 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 along a straight road wz / /y- b6 n)wf5osvah6e/k9rrr am3wand you look to the side for 4.0 s, how far do you travel during this inatten e ksfrz 3/w yvh6ar/)5rmb69wn-/o awtive period?

  If you run a complete loop al*g* 61mchw dwyt;i2nround an outdoor track (400 m), in 100 s, your average velocit 6; dhcynl2g wm**1wity is

  A polar bear starts at the North Pole. It travels 1.0 km south, t,km la( 0lso5 t6j1gmjsv+iws5g)l0lhen 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 average +gisl5t al)j0m0l5l6w ss m o,kjv1(g speed?

  A polar bear starts at the North Pole. It t4,1vy )fb6uhy biru( lravels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km wes)fyh i4 bur,lb6y1vu (t 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/h for 110 miles. d*,4g vttrdkaf6 p25z It then starts to snow and you slow to 35 mi/h. You arrive home after,d 5pftt4z6kg*d2avr 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/h. Whaku-.ju,0r--aoy p3lkkpbxu 7 t is the average speed of the motorist for rl-.u yj-37auok0xk - bkp, upthis trip?

  A motorist travels for 3.0 h at 8bgv 52 1ojfl1 (cfulr/0 km/h and 2.0 h at 100 km/h. What is her average speed for the trfc2lfo5vu/j gb1(l 1r ip?

  An airplane travels at 300 mi/h south for 2.07 al5.pj.cqtc 0 h and then at 250 mi/h north for 750 mj.75l.ptc a cqiles. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) azrb.fw5g-7n for team A can run 100 m in 9.8 s. His rival, the anchorman for .r5nfzw-b7ga 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 team A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 10 s. The car's avere5 n*m4u xgebylq*(0 wage velocity during deceleration was 74 km/h. What was the qee5 *x(y4bu*gl0m nwcar's deceleration while slowing down?

  An airplane increases its speed from 100 m/o 36: tbas 1frd0qoh*us to 160 m/s, at the average rate of h6q 1d:abos3* o0ufrt$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at tu6 t i on)+oo9(sfv5f2+ npuluhe 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 accelerat+,tx oegik++hes 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 c e,bv3eko1patzg v4 73onstant acceleration ov ao1733tbpkzv 4e,g ef $2.0 \; m/s^2$ 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 acceleratiova8w;4aarn : nr bnv:/n o8 arva:/nnn4b:wv ra;f $4.8 \; m/s^2$. What is the cart's displacement during the first 4.2 s of its motion?

  A bullet moving horizk 63*nr -h t.shihu2hsontally to the right (+x direction) with a speed of 404 m/s strikes a sandbag and penetrates a distance of 36.53 cm. What is the aveh36t nk.uhr h2sh-s i*rage acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carrierg:9i0b* +efivfqp(t adc+o3 s. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the ac9 *gei0+sq fvib3o( a+fdpt c:celeration is constant, what is the length of the catapult?

  A car starting from rest moves with constant accws0pk6s;3i ykeleration 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 distanz 8r,jfno, gw+ qp 551tyey;h wc4mqw,fw6 8opce of 200 m. What is its average acc16ww g+ptw8jycwro f,fon e4,z;m,pqq5 h 85yeleration?

  An object starts from rest and undergoes uniform acceleration. Durzsw c3,i2f),.ex owi.8 vpgti ing the first second it travelixc.,w ig3,vt)z .ofe 2i w8sps 6.2 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initial-c68r(mpg zoe q/+b/c- m7ecas31q rnvzeh5bly it is traveling at 16 m/s. Three seconds later it is traveli- b5v /meeg6-q z +(ms3a7zc8qcrn cobh r/pe1ng at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates uniformly at)s4yyvby/2 tkg-:n(i a i2 cet $3.0 \; m/s^2$. 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 canob(psi;w1/fd 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 gebx9o,359 (gfqmtz qp reen, a car that has been waiting at the intersection starts ahead with a cx95qe m9to bzf,pgq(3onstant 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 surface of gd7wuai03 vq6 planet X where the a6gv730 qi waducceleration 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 tcth 5/p*y kxy. ho+gw9he surface of planet X where the acceleration duexhptk 5h9cgy /*.wy+o 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 th/4bb; ;r9pba tm 3sbn m1cr6k/uh +alze surface of planet X where the acceleration due t6 b/rs akm;hbzml t+4b3u a/9r nc;bp1o 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 with9ipjy2bb 8z*qy -8hnq/x6bw n a speed of 14 m/s on the surface of planet X where the accelerj9hq 2b*x6/z bwqyy8 -8bpnni ation 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 0.10 s. ; (fnubxvotc sxd 0t:5tl*4l (If your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler tonv(tbst c oduf:xl;54( tl x*0 fall before you catch it?

  A ball is thrown upward at a velocity of 19.69g d. yocw*j19iva3ey m/s. What is its velocity after 3je9ay oy*1g3cd wiv. 9.00 s?

  A bullet shot straight up returns t1 )1.puyi.27+ qwwtjehrq lb-(gva kzo its starting point in 18 s. What is the initial speed of the bullet?a(ejqli 7q-zpgk w). 1h+ru.ty1v2wb

  A ball is thrown straight up with a9wlslg//, xqf0,/ zzns zkl.a speed of 36.0 m/s. How long does it take to/z0a9z,,/lfl/ kw.s xn qzgl s return to its starting point?

  A ball is thrown downward from the top of a building with an initial speed of xci2 p zfsg0;mu/w/lt2 er,aj7ss8/k 7 m/s. It strikes the ground after 1.9 s. How high is the buildin2wua m/g/xcskssj 8ep 7r,0 fil2z/;tg?

  A ball is thrown straight up with a speed of 30 m/s. (only fills-l41ql )-slyp.rtz g in numerical value in the blanks)t)r -l1y.4z slsqp-lg
(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 stre-w8az,cx/9 xe 3 obkaaight up into the air with a speed of 23.7 m/s. (use $g=10 \; m/s^2$, only fill in numerical value in the blank)
(a.) Calculate the time required for the ball to rise to its maximum height.  (数值)  $s$
(b.) Calculate the time for the ball to fall back to the height at which it was hit.  (数值)  $s$
(c.) Calculate the maximum height reached by the ball.  (数值)  $m$
(d.) Calculate the ball's speed 1 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 12 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 12.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity a1/.svhspkqeih -kx5lnb /76lt t = 1.0 s?

  In Fig. below, what isl 23. aq*es6hdjfbqp2 the velocity at t = 2.5 s?

  In Fig. below, what is the velocitykk7u; or7. tuh at t = 4.0 s?

  In Fig. below, what is the velocity at t d1, f*c :0jex+6mczwj:h ury0u x6hw h= 5.5 s?

  In Fig. below, what is the average velocity from 0 tx.e9kz*y cfve ;p ,ap4o 4.0 s?

  In Fig. below, what is the averagosj sdam1 ;* 7jq(dos9e velocity from 0 to 6.0 s?

  In Fig. below, what is thal)z a .a9hou5e acceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.y..4f+gb8i 8s/ b, blntagtrj;xzyz 4 0 s?

  In Fig. below, what is the average accelej 4i ihujk2a-;- vw/ p-ym8plfration from 0 to 5.0 s?

  In Fig. below, what i sw8fjp t(heg 559+rz)rh8rv:us jzm9s the average acceleration from 0 to 8.0 s?

  In Fig. below, what is the d2l3(/mvf,,k yws, yja ize)zkbx 5a3 sisplacement from 0 to 8.0 s?

Does a car speedometer mh xjh8 j8rcz*hmt( ;r,gh3r-deasure speed, velocity? {speed|velocity}

  An object can have a varying speed if its au8qjwe-py 7+z- k7lz velocity is constant.

  The velocity of an object can be negative cttz*u v 4yrtvgl+r4(rb4 *0zwhen its acceleration is positive.

  If one object has a greater speed than a second obkmy9( b.sqw u8ject, the first must have a greater acceleration(y8 swmq kbu.9.

  Two cars emerge side by side from a tunnel. i fm 26j5h1tzxs .md6j5b+wli 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 d(tdc lid8m2p 78xckp4ecreases.

  A baseball player hits a foul ball straight up into the air. It leaves thee.+i y 4g/v lelsp:s+b bat with a .y eg+ispsl:bv4/+elspeed 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 i7hbc ej n.,b1mts acceleration, how doe.bme hnb 17jc,s it change if air friction is ignored?

  As a freely falling object speeds up, what is happening to its accel e y y0ftnkx5g5l 11s.c(cgb;qeration, how does ityb; nk fl(5g.g1 tqcs1e5yx0c change if air friction CAN NOT be ignored?

  An object that is thrown vertically upward will return to its 7deoawbcu/l f: 8-y9q original position with the same speed as it had initially if air resistance c:w-qfau/9b7 yedo8 lis negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velo begk*(cpgyw,-.o2/ ;oasvpzcity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero flz5ofz 9do ;p4tk+a. acceleration at the same time.

  An elevator moving from the second floor to thej bjmcn9(y ,5o fifth floor making no stops along the way has o5yj,b m9 n(jczero acceleration all the time.

  A rolling ball moveszy*crsc c;.z9 from $x_1=2.0 \mathrm{~cm}$ to $x_2=-7.6 \mathrm{~cm}$ during the time from $t_1=2.5 \mathrm{~s}$ 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 $t_1=-2.0 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.9 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps a)zwxcq3v /uu5. p5lv7ec4 leyround 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 86 m away zg55hg 6l2i8m xbg. enin 12.2 s. It then turns abruptly and gallops halfway.5b 5m 8gg6n2xhieglz 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 frusr(e (ye/ xd/+x y/v(+q voil/lj6 ;f:l bwvoom $13 \; m/s$ to $24 \; m/s$ in 5.1 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 0c+1cc2 y dg-fyx*cv a$16 \; m/s$ to rest in a distance of 68 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reaczev i6-bq 36r2cj7j gxff34cnw,vhz 9h a speed of $29 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.1 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to ess *.+ x52mel7co+jyos pdj /dtwentially top speed abou*d+.lo x/e7ctjjdo p+w s5ym2t $10.2 \; m/s$ in the first 12.1 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 from prgx r c drjkfx6*qw6hs;+9,yv rg-oo*4 u /6sa speed of $16 \; m/s$ to rest in 4.65 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. Assuming qla6 .jcw,r3w,wrqjwlc 3a.6 a deceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trucm4p oq -)iuq3qk 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 i ailw,g;e 7/ntn less than 30.0 min. After exactly 27.0 g;,ate/w ni7l min, there are still 1100 m to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$