Suppose that an object travels from one point in space to another. ) aie+pltp n, 63z+bpobm4az) Make a comparison between the displacement and the distance travelez63 )epb oappa +ztnb4)m,li+d.

  When is the average velocity of an obje7*g:asqc*ncp:y4t (c j +em ghct equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "fro)jgxecz. n:t41odo t;4 zct o:m zero to sixty in 8 s". Thisj4tco1eo:: . n4zxt;cdtgo z ) is a description of

  An object moving in the +x axis expy) dp6):m bbk :ot(yzperiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direct phq+j/zjdxiojs.8no p+* rggoz) fg m74h/ -7ion) begins to slow down as it approaches a traffic loh+ zzponf + po4d)/rj8jgjhs-q/x.m7*7ggi ight. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x directi7m*:eqv:1/t vc+i qf rtpz0 dion) begins to slow down as it approaches a traffic light. Make a statementt/+vvqc iz:er p*q1 d 7imf0:t concerning its acceleration.

  Suppose that an object is moving with a constant velociai 0,86c i fg0wtdouv/ty. Make a statement concerning it0uci t ifdo8va w06,g/s acceleration.

  If the velocity of an object is zero, does it mean thaj5ap 8 n0qnb(pi3g mr7t the acceleration is zero? Support your answer wit a npn5i 0qg873jr(pbmh an example.

  Can an object's velocity change direction when its acceleration is constant? Sjnq :j)un4xyax +3/u5ecm m) rupport your answer with3/mjxrx)n:qunm e5j4a+ c uy) an example.

  Suppose that an object + q4h*b ru960xjp fubwm2snn /is moving with constant acceleration. Make a statement concerning itw 6p+bqrub nh2fn9/x4us0*jm s motion with respect to time.

  Can an object have increasing speed while its acceleration is decreasidoqr5iai8xn qfzh-e e hf *c91a51it,7me5q:ng? Support your anrfci95h n:a1m5tqqha*i5qx e7d,e- fi 1ezo 8swer with an example.

  Suppose a can, after an initial kick, moves up along a smooth ;b gacac9 ai(z7 y2zvv0 7yp4mhill of ice. Make a statement concerning its bi4a 7m2zcyy7aa0 9pc(g zv;vacceleration.

  Under what condition is average velocity equal to the average ofg.w,jg/6ugx2f sv-m xf nmx*+ the object's initial an.wxm2*sugg-x /fmjg 6nfv x,+d final velocity?

  Objects A and B both start at rest. They both accelerate awrb)e i)1bae :i++ uskt the same rate. However, object A accelerates for twice the time as object B +b)aewi erksib+):1u. What is the final speed of object A compared to that of object B?

  Objects A and B both start fromce x2t1gyi* /d rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distandtgx1iy /ec*2ce traveled by object A compared to that of object B?

  When an object is released from rest andzx tupuqx2+0i8 y(g /o falls in the absence of friction, which ofo/yzuux i t0+ pq(82xg the following is true concerning its motion?

  When an object is rele g,p p.byz-dys2s9 9h4gvcf.z ased from rest and falls in the absence of friction, which of the following is true concerning its motion4 ,y9c9zvfp p gszbdh.g.2-ys?

  Suppose a ball is thrown straight up. Make a statement u oybwi 4 uy6 3(gcz bj/d+ph2deu9i-5about the velocity and the acceleration when the ball reaches the highest uecuj93 6 +y /zow5bpd i-4g i(yubd2hpoint.

  Suppose a ball is thrown straight up. What is its acceleration jus5 1pqp) tyb9k dpis+3ord; p4ot before it reaches its highest p;t1o45 pkqo prsi)+9bddp3yp oint?

  Suppose a ball is thropss:4, ns7v9ie8z g zown straight up, reaches a maximum height, then falls to its initial height. Make a stat zso8speg 9,z:7s4nivement about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, -m pk;zwnxb 194mqdw 4then falls to its initial height. Make a statement about the directionx44d; kbqpw m-91wmzn of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downowi*8ix8 o4l)ylnwc+ ward in the absence of air resistance. Make a statement concerning its ayl )w 8oi low4*+xni8ccceleration.

  Suppose a skydiver jumps from a high-s d0wgvmqv2 84flying plane. What is her acceleration when she she reaches w28 vdvq4gms0 terminal velocity?

  A ball is thrown vertically upward with a )olfwxwp :/j,speed v. An identical second ball is thrown upward with xw )/j, :fpowla 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 higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a buildi 34yaoeui/ su5aoe6s :r5u 0uung. One second later, ball B is dropped from the same building.e55u/u u sryu4isa oe:u0oa63 As time progresses, the distance between them

  Ball A is dropped from the top of a building. One second later, ball ua4 6yzsymr*5p6pu5n B is dropped from the same building. As time progresses, the differencep*u5p4y 6rs6 my5zu na in their speeds

  Two objects are thrown from the top of a tall building. One is thrzz tc3:x+ s v,dli 8b9w.n6wfbown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the streetlzsx 8v,f+icb:zd9nw3.w6 b t?

  A brick is dropped from the top8 *oadvqvkteqa+:pp, ;ixn;/ of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare a p+*daq; itqo; /v:ne8,pvxkthe accelerations of the two bricks.

  An object is moving witrbfzmnhn +-6t ql/d89 h constant non-zero velocity in the +x axis. The position vers h9+z6l -qn8/rmtndfbus time graph of this object is

  An object is moving with constant non-zero acceler7jsl:6 qfj4uom 0 nqt-ation in the +x axis. The position versus time graph of tfuq0qsjomn46-:l 7j this object is

  An object is moving with cav pg ngq7 z;gh/7b ocr:2j7 n99tr)lxonstant non-zero velocity in the +x axis. The velocity versus time graph of this object isn 99cohgxj r gglvt)bnzr772/;paq7 :

  An object is moving with constane/e(9b t ryai:t non-zero acceleration in the +x axis. The velocity versus time grape e/i:tbyr(a9h of this object is

  The slope of a position versus ti ,mpbo djg : 2 sg/a-yq6/nn+(4qzatghme graph gives

  The slope of a velocity versus titudlqff 9 j3z85 en-m3;k(u jn ys*w+rme graph gives

  The area under a curve;ucv* l0bzwiz 8:ws( x in an acceleration versus time graph gives

  The area under a curve in a velocc (5mwy fi(k9nmxt+*zity versus time graph gives

  If the position versus time gn9* q tyo:ti6vm(ofql8)3 hj braph of an object is a horizontal line, the object f6) 89noym q( qivt t:b3*hjolis

  If the position versus time graph of an object is a vertical line, th wav73f04n v-t.k+ abi 7rvtbse object isiavks -t40bnrawbvv+t f737.

  If the velocity versus time graph of.xb,1 epuf,hu an object is a horizontal line, the object ixpf,,ue1.b hus

  If the velocity versus time graph of an object is a straight line making an ang945t7 tl;qxziag 9lg mhsz(w/h jei 87le of 30 degrees wzi5x9a97 zwmhi8jl;t(t4lqg g7e/s h ith the time axis, the object is

  An object moves 15.0 m north and thenru19ugfmav37hb 1 6ln 11.0 m south. Find both the distance traveled and the magnitude of the displac 1mul71n9gafb ru36 hvement vector.

  A boat can move at 30 km/h in still water. How long will it take to move 12 - qyl1vi74f;xn q(hqu4zneo/yj ;;gfkm upstream in a river flowing 6.0 km/ ni y-;ln;ff7zquyqvq4o gx1; 4j(he/ h?

  55 mi/h is how many m/s? (1 mi ve n-nx6k/:y 0 t;h2dsdec-kt= 1609 m)

  What must be your average speed in order to travel 350 j )v ..mdvio-l89e7krkrz 7gxkm in 5.15 h?

  A runner ran the marath yeal0i16 pdo-on (approximately 42.0 km) in 2 hours and 57 min. What is the average speed of thee 6a0lypod1-i runner in m/s?

  A car travels 90 km/h. How long does it take for it to .2jut1 qfx(o1 h fn(3x:r8vd9t0ylz jvjko3mtravel 400 km?

  A ly (light year) is the distance that light travels in one year. The speed of q d. :nuw)km-s:yrr9tz k42qx light is su:w n. m-qy 4t)9zkdkx:2rqr$3.00 \times 10^8 \; m/s$. 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 fc:o4 *;o xlbuadvh* yc7+s:vmd4vh/ror 4.0 s, how far do you travel during thish4y4 :+ buvorc**av osl7mx;cd: h/vd inattentive period?

  If you run a complete loop scz;+td obb brcr71p4,c b,p(around an outdoor track (400 m), in 100 s, your average veloccd4b,p1 7pozt ,b(b+cr;s rbcity is

  A polar bear starts at the North P4e( xr ujjrai 7mm)v):ole. It travels 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 takes 45 min )ia j4:mjm u)re(r7vx. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km sou g8xnh: .fuo1uth, then 1.0 km east, then 1.0 km north, then 1.0 km west to retunx8uu: .1gfhorn 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. It thvrezpxhe z:(p .66tw7 en starts to snow and you sh wzpv.z6x ept6:7r e(low 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 km at 80 km/h and 160 km at 100 km/h. What 9gd jyhv+feoj2j) :r4 is the average speed of the motorist for this tri+yvjj e g:f94ojh)2drp?

  A motorist travels for 3.0 h at 80 km/h and 2.03v; pg4gx9o z qxq;+;/g jryur h at 100 km/h. What is her average speed for the trvr rjx;xg zy+/9qg;o uqgp3 4;ip?

  An airplane travels at 300 mi/h south for 2.00 h and then amkxkcugl6cn 52 umx**49(ece t 250 mi/h north for 750 miles. What is the average speed for the t k49x6gue c *m52lcem*nukxc (rip?

  In a 400-m relay race the anco0 paxt ,kbr7iye03, vhorman (the person who runs the last 100 m) for team A can run 100 m in 9.8 s. His rival, obxiv03,yp 7ke0t,ra 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 team A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 10 sp, jgzzk l q+p8l39 :ig7g-aof. The car's average velocity during deceleration was 57 km-oplazkp g9g8q i37 glj+z,f: /h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 1 3fji6 ;hxiwv -( *qj9*r)ax iipidu4t00 m/s to 160 m/s, at the average rate of x;* -i(t4 rhjd f6uqpjv*iwx)i ai39i$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelnw( /n drc3/)ru(ltpcerates 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 accelerates sn69 5rrrm*8 m07baac5b f.i rcu3i2fxw.vjmat $4.0 \; m/s^2$ 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 r236 xn69gi ;1gtna sh a .wt03ihmnfcthen speeds up with a constant acceleration ag6 f 3a c0h9itsixr mg6h3n; 1w.tn2nof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 5.6 m/s experiences a con4,k : k xn6a9yd;oipvwstant acceleration ofodvy,;n iwx4ka:p k96 $3.2 \; m/s^2$. What is the cart's displacement during the first 8.2 s of its motion?

  A bullet moving horizontally to the rig) pkdrcu );la2 1t5puyht (+x direction) with a speed of 415 m/s strikes a sandbag and penetrates a distance of 59.49 cm. Wht;ldup p2rk5u )1cy )aat is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carrier. It reh *v,p gyvg/ -msm/e8yaches a speed *mpem/vh ysv y/g 8,g-of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant acceleratc g0obp2mg+ t,)4f6wk fm g.kc0jg lj4ion 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 distance of 20+d6o4qdem bwsav; *-,hwrd i+0 m. What is its average acceleration?idrm+ as-dvd *;4,wqeh w6+bo

  An object starts from rest and undergoes u 1(qkbd1adn 4xy1 6afugus.6aniform acceleration. During the first second it travels 3.1 m. How far will it travel d6dbau1 46aan.f(x1 k1q ugsdyuring the third second?

  An object is moving in a strav6( xilieo. e-gjb. *pight line with constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. Howxe* i.gi eo(vl.6p-bj far does it move during this time?

  A car starts from rest and accelerates v0uvb0ke *oirf3db- .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 r7tvw5fq.f w ,ggr+1gw- uek k/oad can decelerate at about $5.0 \; m/s^2$ when braking. Suppose a car is initially traveling at 55 mi/h.
(a.) How much time does it take the car to stop?    $s$ (only input numerical values)
(b.) What is the stopping distance?    $m$ ((only input numerical values)

  At the instant a traffic light turns green, a car that has been w yksb7i 1uv,o.q94, nclc gu0jaiting at the intersection starts ahead with a constanu ncsj1lu y7iov, 40 9cq,bk.gt 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 xoo7j1x e kda8c(ck/,speed of 12 m/s on the surface of planet X where the acceleroj o 7,ckak1x/ec d8(xation 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 *l6 51z,2w1wgpx:mb r twu2zzir(g0sc,s dou of 12 m/s on the surface of planet X where the acceleration due to gravity is uz ml,0*gub z:2 1w5x( p r16zcrtiwd,2sg sow$1.5 \; m/s^2$. 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 of planet X w(arvum j/mt; p2n:ew3here evu nr;jpt ma/3m w2(: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 h9j5bwu)m x 7lmy9,sw of 14 m/s on the surface of planet X where the accel 99h,yxw5wjmlb 7mus )eration 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. Ifcv fk.*qf;2e z5 l/ulp your friend holds a ruler between your fingers and releases it without warnilk ;vqz lf.cfue 5p*/2ng, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upw,kr ohsnz;9k2-x . hldard at a velocity of 19.6 m/s. What is its velocity after 3.00 9z2okkrs;x h.nd-lh, s?

  A bullet shot straight up returns to its starting point ic uncs:zg3l71py3uxj*r cdc3b,962ey tn g*wn 5 s. What is the initial speed c 3*6u29y j *z3p,dcg yur:tncbc3 lwensx71gof the bullet?

  A ball is thrown straight up with a speed oc;q 72g9uv m3 ci*gjjwf 36.0 m/s. How long does it take to return73q*gc w9 ;micjv2 gju to its starting point?

  A ball is thrown downward from the top of a building with an ixpez fqxj7 yxs4t;- kaa7k545nitial speed of 15 m/s. It strikes the ground after 5.7 s. How high is the buildin;5z5xatja f p7 qxxe k4ys7k-4g?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numeri.aych lrh lqd83 qy,7vf)8 (lafl +2ppcal valf7f8 2h(a8.prvhaly+cl)lql3dpq y ,ue 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 wiku5 uh/fo c03o mub 97pj4l3)chamt4w th a speed of 40.6 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 9 m above the point of contact between the bat and ball for the first time.  (数值)  $s$
(f.) Determine the time at which the ball pass a point 9.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the vf.;my1ap ffmp2 (kf e7elocity at t = 1.0 s?

  In Fig. below, what is the velocity at t = di ( n3b2o(ffo2.5 s?

  In Fig. below, what is the velocitf 3h8nykm)2 *hk2 efd3u cv)xny at t = 4.0 s?

  In Fig. below, what is the rktjgm7s+7 5 8wdmum0velocity at t = 5.5 s?

  In Fig. below, what is the g a4d1b(od)rvaverage velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity from 0 to 6.h5x9g rq,nc)9uh q2al0 s?

  In Fig. below, what is the acceleration at 1.0d6r*ugm+tr.** a+8od l 5fp v my6g.sx tnpq.w s?

  In Fig. below, what is the accelgmifcoqy1(ou+h06c:2 p1ki m eration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 8 tii/yvz- 3owto 5.0 s?

  In Fig. below, what is the a2dq, tbuh2.2/qipm foverage acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to j/4(gs,eox5 v ,tbtcg8.0 s?

Does a car speedometer measure spee huw0vid t/n*r2((w hnd, velocity? {speed|velocity}

  An object can have a varying speed j/zns oz0.y fu7kg,k+if its velocity is constant.

  The velocity of an object can be negative wx i.invy* qzedo(tihpl 15 txv6p74- 9hen its acceleration is positive.

  If one object has a greater speed than a9i3sa0q dhhc 4 second object, the first must have a greater acceleration. s ca3dhi4h09q

  Two cars emerge side by side from a tunnel. Car A is traveling with a3yfx5*3h98v0poj 8ax j7jjh s)os rx i 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 increasi*vulu5j n3zbja.u)7r+ vu0 pd ng in speed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It leaves theuunbh/h;se(y7vbw tz6q 6 5y) bat with a speed o ;u /wh6ubbez yvyt75q()6 snhf $120 \; km/h$. 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 acceleration, ulc22f y04kmlhow does it change if air f4m22lk0y lfucriction is ignored?

  As a freely falling object speeds up, whats3hvu3fh )t7v.cn6 wq is happening to its acceleration, how does it change if air friction CAN NOT be ignore.hhtvsuq3wcv7f 36n )d?

  An object that is thrown vertically xtb7.vy 7 2yai8n*-evcqo; ukupward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, 7xy;k o.n * 7ta2qe uy8-vivcbhow will this result be altered?

  An object can have zero velocity and nonzero acceleratio,9de44qzk zd/3dmpns 01b mc 7h+qyxfn at the same time.

  An object can have nonzero velocity and z1c*nl a9/vw kiero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor md,lmwr(a+) wb5,ici n aking no stops along the way has zero accelerationica +b()r5wl w,ind,m all the time.

  A rolling ball moves fro 7i67btmd.hs fm $x_1=3.3 \mathrm{~cm}$ to $x_2=-6.1 \mathrm{~cm}$ during the time from $t_1=1.2 \mathrm{~s}$ to $t_2=5.0 \mathrm{~s}$. 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 $x_1=3.2 \mathrm{~cm}$ and at $t_2=3.6 \mathrm{~s}$ is at $x_2=7.8 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight co y kx.oeyy7n8ld(lr1yf2to 1, mplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.2 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 100 m 2q /7+qb .whbbk0qyabv5jrp :away in 8.5 s. It then turns abruptly and gallops halfway back in 4.7 s. Cal .bq r0v7p+y/q ahwbbb52:qkjculate (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 cpy9usk;d,b -$11 \; m/s$ to $23 \; m/s$ in 5.3 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 lw7 s:qz-:0 qoz(znkf;bv 4lt$21 \; m/s$ to rest in a distance of 73 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must rerli *g57p4d 99 ioa2t4t0fbos k7 hnfdach a speed of $32 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.4 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top spetr0w 18jg)stp ed abouttj1g) rp8 sw0t $11.3 \; m/s$ in the first 10.2 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 f 7z6)548ylsiw f/ez trvh(njdrom a speed of $17 \; m/s$ to rest in 5.05 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, x;ek ia (eiied9 p3w;q3 :8mnua car leaves skid marks 92 m long on the highway. Assuming a deceler iwip ;a8:um ;3inxdqeee (k93ation of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goictndj;yl7b5+ uizs 8;ng $25 \; m/s$ 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 rktn6ma * rnu2(un in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then accelerate at nt* 2a 6n(murk$0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$