Suppose that an object travels from one pviftsf( aeh4j clns ;r5+ 15 bt4fg1y*oint in space to another. Make a comparison between the displacement and the distance traveled4fgs4+es1jfbh*v a51l; (ctniy r5tf .

  When is the average velocity of an object equal to the instantxx+5li2xvgw-lm mm o 1;tp. )taneous velocity?

  A new car manufacturer advertises that their car can go x03q) jgzpr(m "from zero to sixty in 8 s". This is a d0z3r(xqmg)j pescription of

  An object moving in the +x axis experp5z 6muty)q d *xpiq/6iences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x directiov 1nv kd79oiu(n) begins to slow down as it approaches a traffic light. 7v i1u9nodk(v Make a statement concerning its acceleration.

  Suppose that a car traveling )ayjwh2/ wsthl6/2d pnd7i0 rto the West (-x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its accen/)t j2i72 0wa/y rdlph w6hsdleration.

  Suppose that an object is moving with a cons87zx-1cu u bjt zgd*z7tant velocity. Make a statement concerning its gt*-zuub7 1zzjxd 8c7 acceleration.

  If the velocity of an object is zert2lmb-5w, oh wo, does it mean that the acceleration is zero? Support your answer wit-bm tw,ol2hw 5h an example.

  Can an object's velocity change direction when its acceleration is constant? Suu3j 1u3+. cdfzks+(umynz l/ d,; zzzrpport your ans zdc 1usl+j(fz3u/ y3. ;+r kmu,dzznzwer with an example.

  Suppose that an object is moving withx5o8hyb +4 2fcs/dyaa constant acceleration. Make a statement concerning its h+d 5/ abo48fyay2 xcsmotion with respect to time.

  Can an object have increasing speed while its acceleration is deaw-8nhg /82f 3vp6t lwsq8xt: 9mdu vgcreasing? Support your answer with andh8/npqawt :v8wu3 -l 9m8 gvf62txsg example.

  Suppose a can, after an initial kick, moves up along a smooth hill of ice. Mak 2v-mir0xo c p-j-z+x t9.hkjxe a statement cjxh0 mjc9r-k +-2xzptx-.oi v oncerning its acceleration.

  Under what condition is average velocity equal to the average ofzkgwx-u05dm ; the object's initial ag0md5k-w z ;xund final velocity?

  Objects A and B both start at resl:q kxs,l. bnu;am2p4 2 /lxqu1f(wzot. They both accelerate at the same rate. However, object A accelerates for twi2mwl:fa ; 4q.l1x sl(x qbuzn2okp,/u ce 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 from2w/,oc;nbfyz 05k6 8fr f gxpa rest. They both accelerate at the same rate. However, object A accelerates ;cgo fxk/82z5b6f nraf0yp,wfor 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 and falls in the absence of friq z( z2 q-y(.wqd aaw5mg6a6gxction, which of the following is true concerning its moti6q-dg(5q (ma2y6a zaqg. wz wxon?

  When an object is relelhrv6j(4 cs/ g 4c:d kfa/t6otased from rest and falls in the absence of friction, which of the following is true concerning ca6jsg (od/ 6k4lh cf4rt/t:vits motion?

  Suppose a ball is thrown straight up. Make a statea 9nv+ .efcp1qxf:nclm1 (i v;ment about the velocity and the acceleratn v c9fi:l1(e+ v.;xpfm1ncqaion when the ball reaches the highest point.

  Suppose a ball is thrown straightk53(a xl* )r2jvzoqc9bloe.cww+i b . up. What is its acceleration just before it rq9wic*wx. vr.2 az(c l5b+eb3)o okjleaches its highest point?

  Suppose a ball is thro h;2qx;e +(j*pdg+mgj2 5)ejzpvgpwcwn straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of ;pp)*h;2z eqd5+(gjmgjxp +v je cg2wthe velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to its initu a746wpab uv.ial height. Make a statement about the direction6a4 w7b.vpu ua of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward sxwl2)udi )/din the absence of air resistance. Make a statement concerning its accele dd)2sl)xwu/i ration.

  Suppose a skydiver jumps from a high-flying plane..9ltw*d fj n;b What is her acceleration when she shelbnt.* 9j ;fdw reaches terminal velocity?

  A ball is thrown vertically upward wickf )w6n qd p)4wh+n.ath a speed v. An identical second ball is thrown upwardnc.+ k d4wnq 6wpfa)h) with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from t 1jri4icd9 f2fhe top of a building. One second later, ball B is dropped from the same building. As time progref 2r4ijdi91fcsses, the distance between them

  Ball A is dropped from the top of a building. One second later, balmp5p vt hlav9 477o9 qfozd/s2*fk) ecl B is dropped from the same building. As time progresses, theo 4vf 7o*9d2apf h)tv5p kl7em/9qzsc difference in their speeds

  Two objects are thrown from the top of eyj;a 4; -f,o(bgmgiw x87u jra tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds whe ejy78bfa(im ,guwjog4 x r-;;n they hit the street?

  A brick is dropped from the top of a building. A second brick is throwss/ead69 t mnu7a/ -sxn straight down from the same building. They are released at the same time. Neglect air resista n muas-9e/satx7 6sd/nce. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velociti a--5 kah:6+8vs vei5lpf1w vr1p tegy in the +x axis. The position versus time graph of th er5:a1sph f t5v8pv61eiag+kv i-- lwis object is

  An object is moving with constant np)m0pijvap1tq a9tgw // 6 t)lon-zero acceleration in the +x axis. The position versus time g t96pplq1/ )aj pgt0)mitwva/raph of this object is

  An object is moving with constant non-zero velocitym zv6h;l(wjtbn 76) qpzm f+3kv5w*s u in the +x axis. The velocity versus time graph of this obf6l3 u jq 7)ms5tkmwvbn ;pz(+vz *h6wject is

  An object is moving with const fzp1y r6*0gqan55nj jant non-zero acceleration in the +x axis. The velocity versus time graph oyn j gq0j6p*n55fr za1f this object is

  The slope of a positgn c1izkoe2wht.-68 sion versus time graph gives

  The slope of a velocity versus time grcfjwt dlkt)d tyw4;v6;,h: w+aph gives

  The area under a curve in an acceler;f6m;yr lec: wation versus time graph gives

  The area under a curve in a velocity vers*(ec x/7z .:zowufyxxus time graph gives

  If the position versus time graph of an object is a horizontal lin2ryzzniva) ot9k2kkun3.f,1q *p v4ne, the object i,v it)2o9.*nzuzkkfy21nn4qp r3av ks

  If the position versus time graph of an object is a vertical g 4/c yyx9rr-pfkwga6 ,,ik4lline, the object is4x,gf agr,/wlk 4yc kyrp-i69

  If the velocity versus time graph of an ob2+d40js+ vcitaer p 4 s(9nzlrject is a horizontal line, the object is0 +4zptevc ar s4ldirn+9 (s2j

  If the velocity versus time graph of an object is a straight line makqux;08g px f(gfp1z(yi( 3d g 2djf.wving an angle of 30 degrees with the time ;fd (v x(px j.udw 12 0zggyq3(8pffigaxis, the object is

  An object moves 15.0 m nor(uveey:9 im 0u.gl1 tbth and then 11.0 m south. Find both the distance traveled and the magnitude of (b:1.ute9luemy gv0i the displacement vector.

  A boat can move at 30 km/h in still water. How long wila 8f(jkw ; ,ej*./fuif:bzjz9ai0 rhvl it take to move 12 km upstream in a rbf0rj aj;9z, fjwzvhkuaf:e8*/.i(i iver flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 hfsjoq66*d3/ dxyqc 4mi = 1609 m)

  What must be your average speed in order txgr )ta ybov) *r *lftvah )7cem6z/(ww18z 4to travel 350 km in 5.15 h?

  A runner ran the maratjkfa37ef g+ 43bk k7. skw/wexhon (approximately 42.0 km) in 2 hours and 57 min. What is the average speed of the runner in m/s?w/gk+aj sf 7kk3 k4wbxee 73.f

  A car travels 90 km/h. How long does .qf6oy+jq3z+ c-rlvh,cc ikd o vkt9:b (d9e1 it take for it to travel 400 km?

  A ly (light year) is the distance that light travelst3;4eo5( h0ow/b 4jr lu4ijdo1rdv nn in one year. The speed of light t3h4oo/rjd 4 (;e5ubojdw n10 ilr4nv 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 strai mmg)2 ydzzn,)ght road and you look to the side for 4.0 s, how far do you travel during this inattentiy m,dg)m)zn z2ve period?

  If you run a complete loop around an outdooy tcq) 9ie0 +s vj5i46 zvoc+1wxd0bter track (400 m), in 100 s, your average v vqt 1os0)ijvyc+edtwe x65z 4ci9+b0elocity is

  A polar bear starts at the North Pole. It tmd jwe9p3i 8a(ravels 1.0 km south, then 1.0 km easwj8 d9ai (3mpet, 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 speed?

  A polar bear starts at the North Pole. It travels y,5,f,yz2ae .wlj817 dinhuwji; mpf 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its smiw8, ,7pa dn jyjef.y 2uz l1,hwif5;tarting 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 thenvubp4a 4 1ou/y starts to snow and you slow to 35 mi/h. You arrive home af/14bpv ao 4uyuter 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 is the averezdonv o /2,3iage speed of the motorist 3/zeo,2ovndi for this trip?

  A motorist travels for 3.0 h 07r9flx ;lw. a9/v zoo*sjpmfat 80 km/h and 2.0 h at 100 km/h. What is her average speed for t9 r.fo9s7 pf;lxwz 0ma*v/ojlhe trip?

  An airplane travels at 300 mi/h south for 2.00 h and then j p jm41 as,1ncqo:/c7n1xnbhat 250 mi/h north for 750 miles. Whap jocnnh4sj1: 71xn/b m1qca,t is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who n, qh). a5+pfysra/nhhz9p nlz 5/pa:runs the last 100 m) for team A can run 100 m in 9.8 s. His rival, the anchorman for team B, can cover 10h95p)az/hyznnq/.pfar :+an sphl5, 0 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 9 s. The car's aver 60bhiqy656sfieg n ek y15x.nkg.gf-age velocity during deceleration was 77 km/h. What was tk6f1bsn .yh5i60xqk 5yn g6gf-ig e.e he car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average rate of2v 6e/ jeo ynvljo5b/0 beo/ jlnev5 j2o v6y0/$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acsryq+ 8tqd+/h celerates 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 accelerate - d9sszdi8 t.drm-(jvef7ga6s 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. Itf ;p8hjwmq)cl d)a8 c* then speeds up with a constant accelerationwm;jh 8) )8cpdql a*cf of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial v 16gxajp3wx6w *ko8 unelocity of 2.0 m/s experiences a constant acceleration ofu1 63* 6axgk8xwow pjn $2.4 \; m/s^2$. What is the cart's displacement during the first 9.1 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of fq;)0huuhm,vq h6 e4q294 m/s strikes a sandbag and penf qh uh4;h60e,qq)umv etrates a distance of 40.11 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carj/cbpbj8le-/w .yun-aqh 88zz 7qxo7rier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant, 887ox-hqe-ubzaw/ 7j zb8p/yljcq.nwhat is the length of the catapult?

  A car starting from /b *lm2m )p0( vortniv9j x-aet4a,barest moves with constant 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 6:r q hiy jit59 rwvau-8tt9p5a distance of 200 m. What is its average acceleratio y5vaj rt pi5h:w68tiq9 u9tr-n?

  An object starts from rest and undergoes uniform acceleration. During the fir4p ) 2ew m)yhi0:*vkcpwaxtss t9 ,q4wst second it t,y2iw9pp)q c)0*xtt 4 wea wvkhs m:s4ravels 7.6 m. How far will it travel during the third second?

  An object is moving in j itb;i(bhhi:.cbs7 4 a straight line with constant acceleration. Initially it is traveling at 16bh7j4bi( i ;tc.s hb:i m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates unifw7xa 7/oblxjk dh,9 w1ormly 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 bu6 )z,fbn2pson a dry road 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 traf.ws etg 6etg3w utw,r,dhkb t2-n8pw3x y) g4/fic light turns green, a car that has been waiting at the intersection starts ahead with a constant accelerat3t/ktw)6b, wn4gg- tdpsxw y 2ru3e., egth8 wion 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 upwa5q6 8tpb w4wrpl.x z+culc9 4grd with a speed of 12 m/s on the surface of planet X where the accelpzc c5.twp44g8b9qlux w6rl+ eration due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward (ya l. rjim+k8with a speed of 12 m/s on the surface of planet X where mj8+y akl(ir. the 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 upward wi,9fz7gg r/wiijd6* pith a speed of 15 m/s on the surface of planet X where the7dii6i z/pg9f, w*rgj 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 14db;w 3b*x0c+f 5pe j9/sajm qx m/s on the surface of planet X where the acce3*ew/x09sjcjqp dfm b 5ax;b +leration 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. f4rd5/l,8*(vok0tba sf seff uyo(v2If your friend holds a ruler between your fingevas/4u*2l 8eo0,kb(frft sffvo (5d y rs and 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 vel vb9.sonf twoz*wz15 .ocity after 3.00 s?s .59zw. vzt1n*bwofo

  A bullet shot straight up returns to its starting point in 7 s. i mygml9m)ly-p3 *u0; ax9bduWhat is the initial sp;laib39-d )g mm9 yupyl *u0xmeed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does852cju p ;tz*/kj/( oii(xfmcucs*gf it take to ret;g* u( p/2s/f5j cj8ifz(utm*kocixcurn to its starting point?

  A ball is thrown downward from the top of a building with an initial speedz +tm3 c; .c;;8jnkis*ejkwp o of 29 m/s. It strikes the ground after 7.4 s. How*co+3ti;.zm;8epjc wk nskj; high is the building?

  A ball is thrown straight up n7 l1gqdicdr*e73ss -1n7jvw with a speed of 30 m/s. (only fill in numerical value in the blanks i11dn7j gvl7c-r*3 dqn7sswe)
(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 at92r-/5w7wc.f is y hyjl2a vzir with a speed of 27.8 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 7 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 7.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the iqtff0ic ac-au12b1 (wq4 o4gvelocity at t = 1.0 s?

  In Fig. below, what is the veloc k8qsg yi.f3o u s;0v8dd2wn3sity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0 x/ydr0h jn*pv9h0 ;o ls?

  In Fig. below, what is the vel .b veu0 , )(qn-ie):yyx bmg (yxj.grrru/rt,ocity at t = 5.5 s?

  In Fig. below, what is the 6sp)p6hneak+im8+ me average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity from 0 to 6.(fd/ rsduay ,f,-, p-m(wbjis0 s?

  In Fig. below, what is the acceleration at 1.0 4qg)983 t0zuxea wguk s?

  In Fig. below, what is the gpa:5 3bs,n1gcsjdf +acceleration at 3.0 s?

  In Fig. below, what is the averagog+t-q8t k 9xge acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration f vbvi+vxynwm/k9. e3n 3 lyy99rom 0 to 8.0 s?

  In Fig. below, what is t*0 /h hlrcczfnl)237e ynaqk 9he displacement from 0 to 8.0 s?

Does a car speedometer mdesl 2n2yu 13keasure speed, velocity? {speed|velocity}

  An object can have a varying speed if its velocipu)5t7hi -gw l rd*pv;ty is constant.

  The velocity of an object can be negative when its vn8j8 5skt4dg acceleration is positive.

  If one object has a greater speed than a second f)q t:t5jbe: nobject, the first must have a gr:j nbq): ttf5eeater acceleration.

  Two cars emerge side by side from a tunnel. Car A is traveli1s6gze2 71 pymenf* icng 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 i:ov k00upy+qtts acceleration decreases.

  A baseball player hits a foul ball strxl/zn j;)*punaight up into the air. It leaves the bat with p; nljz* )u/xna speed 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 4ug:/0 jovm ldc7yw1vto its acceleration, how does it change if air frictionv41d7 w gyolj0uvcm:/ is ignored?

  As a freely falling object speeds up, what is happenin3/ kvhm2n23lfbcv c7n g to its acceleration, how does it change if air friction CAN NOT be 7h2b23l cvn 3/ mkcvnfignored?

  An object that is thrown vertically upl ll3mrc3i .0+gl;djeyi9)qr ward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how willig)l0 . q;3r39cdje+ mli llry this result be altered?

  An object can have zero velocity and nonzero acceleratdg))ex iq+u4c1zyve *ion at the same time.

  An object can have nonzero velocity and zero acceleratq f- sgcr8m1j.ion at the same time.

  An elevator moving ffsei 23 vq;l4nrom the second floor to the fifth floor making no stops along the ;iqs3lefv 4n2 way has zero acceleration all the time.

  A rolling ball moves fvf0 q exc*u,0sh *vxh,rom $x_1=1.7 \mathrm{~cm}$ to $x_2=-7.0 \mathrm{~cm}$ during the time from $t_1=2.8 \mathrm{~s}$ to $t_2=5.9 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.4 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.3 \mathrm{~s}$ is at $x_2=7.8 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete lapsugq nm ,y8fmd vp83b-9 around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.3 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away u7o no)sy b+gaf mcr0r8*r;7 kfrom its trainer in a straight line, moving 90 m away in 9.0 s. It then turns abrupt*; 7fr7sobg0)uomk n yac+r8r ly and gallops halfway back in 4.6 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 frnx +m h8-tljr *o-fg(iom $12 \; m/s$ to $22 \; m/s$ in 5.4 s. What was its acceleration?  (数值)  $m/s^2$ How far did it travel in this time?  (数值)  $m$ Assume constant acceleration.

  A car slows down from /q,4+lgnoda +bf q;nn $22 \; m/s$ to rest in a distance of 61 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a spli91 ,rcjfwe; eed of $26 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.6 \; m/s^2$ ?  (数值)  $m$

  A world-class sprintexd, -:va: vdcer can burst out of the blocks to essentially top speed about : xaec -,v:ddv$10.1 \; m/s$ in the first 14.7 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 dgnwa :gyi33g4m y4d5 a speed of $17 \; m/s$ to rest in 5.41 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 hibnn9fa78 sze7ghway. Assuming af8asen9 b n77z deceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck (mdfb+nn0l /igoing $25 \; m/s$ 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).    $m$