Suppose that an object travnl2k + vmm3hj2els from one point in space to another. Make a comparison between the displac2jm l v32m+hknement and the distance traveled.

  When is the average v47 xl9gi olay;elocity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises thy.;efy- vhal7: tggd rwfvw406 2,hy,nux /ndat their car can go "from zero to sixty in 8 s". This is a description o ,4/veldva,t:f -ydywxyrn7gw0h6.u ghf n; 2f

  An object moving in the +x axis experiences an accoud amvhsi1,,dr*zdh 7iq )u 00g :myf0/g6pieleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East r jdfj28ahkg 4 2(kjy8(+x direction) begins to slow down as it approaches a traffic lhajk2f8kyr jgd2(8j 4 ight. Make a statement concerning its acceleration.

  Suppose that a car travelin 0 .4i0t7,wllc frxt /csu3cng 3g0tobg to the West (-x direction) begins to slow down as it approaches a traffic light. tx3 clil0gb.tsf0o 3 g,7c 4ut0n/crwMake a statement concerning its acceleration.

  Suppose that an object i+2p tut qzs9hd:o l83zs moving with a constant velocity. Make a statement concernin8t 2h+:q zls t9zu3dpog its acceleration.

  If the velocity of an i:y) pfi1:j/:e it l+g thi/nnobject is zero, does it mean that the acceleration is zero? Support ti:pe:t/ il1nhg:y)j if+in/ your answer with an example.

  Can an object's velocity change direction when its accelerati:-mjtu (c+s uwon is constant? Support your answer with an-(+ stu :wmujc example.

  Suppose that an object is moving with constant accelerat/. ytbinqfm (1ion. Make a statement co (nqmbytf/i. 1ncerning its motion with respect to time.

  Can an object have increasing speed while its acceleration is peayzp2c:r/0 8h mr9rjtgs 27 decreasing? Support your ans :2m0c82y rrjtr 9/psh7pge zawer with an example.

  Suppose a can, after an initial kick, moves up along a smootl4f1r6 o0(d ofe+yqnkh hill of ice. Make a statement concerning its accelerate oy06o1 4+dfqln( rfkion.

  Under what condition is average velocity eqq fy*h1v 2-but57gq la jp/9shual to the average of the object's initial and fi psb-2 *avyjtqu fq7h5l9/1h gnal velocity?

  Objects A and B both start at rest. They both accelex8wx(qib gn/ p i ,nhr)vke61;rate at the same rate. However, object A accelerates for twice the time as object B. What is the final speed of obx;)i p/kbgve(1ixnq,8rn h6 wject A compared to that of object B?

  Objects A and B both start from rest. They bot87ucvlby p9ugjz/5 x2h accelerate at the same rate. However, object A accelerates for twice the time as object B. What ux 278vuy/gz5 b9cjlp is the distance traveled by object A compared to that of object B?

  When an object is released from rest +;x+u7 ivxag5g t6yp jand falls in the absence of friction, which of the following is true concer+u+x j6i t5x;p ygav7gning its motion?

  When an object is releaser ixsu9uo0pn8 ic.) 3vd from rest and falls in the absence of friction, which of the following is true concerning its motio n3.px rovi)9cu is8u0n?

  Suppose a ball is thrown straight up. Make a state o2sx(a gi2ufqz 73jm4ment about the velocity and the acceleration when the ball rea(m4 sg7 oi2aqxujf3z2ches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just 4v0gg.yt/vzexi z38 nd9vbu1 ;zdk .rbefore it reachezg8 v.r0;bn v4uzz edk91it xy3.v/g ds its highest point?

  Suppose a ball is thuhi 8b0hg.9ypyg1e4-s: s fb; bib 5mqrown straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of tg.bm1 8g h4b: b iy9usp-by05eshfi;qhe velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then faxpla.v6()u h slls to its initial height. Make a statement about the direction of the velocity and acceleration.ax p lh)6vus( as the ball is coming down.

  Suppose a ball is thksu (,bv )qtk. n5o(9lknm5im rown downward in the absence of air resistance. Make a statement concerv( s o.t)95lk (m,nnik5um bqkning its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her acceleratio; 5omwvt;+;io *v dwgdn when;g5o;dvi ow*v ;m +dwt she she reaches terminal velocity?

  A ball is thrown vertically upward with a spe7 bl2*kje5pp hn37uxtrhwbkz 5)o1/ f ed v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the seco3z 7 obn7h 5l5)kwx /hup*fer1tjbk p2nd 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 buildin2b8w a ma t-0hjkl-f:pg. One second later, ball B is dropped from thjwfalp -at-82b0khm :e same building. As time progresses, the distance between them

  Ball A is dropped from the top ox yb xl0(9 2k64csrtcab y*)ynv:h/:f cnvv 2of a building. One second later, ball B is dropped from the same building. cv6o/v:yn( 4*vhx2 :2c0b9ytxy b nlfa )srkc As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. los9nnj/7dqtz/f03rp(e2 lcm dv* q4 One is thrown up, and the other is(znol79 mt 3/ds/efn2qvlq *0crjpd 4 thrown down, both with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown stre.2w2ar 6gbb caight .2r2b6gceabw down from the same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with 8ucudu., xcg)constant non-zero velocity in the +x axis. The position versus time graph of thi). gc xduc8,uus object is

  An object is moving with constant non-zero acceleration in the +x ax+nc ,n8pyzs8 pis. The position versus time graph of thisny+8z,ppc 8sn object is

  An object is moving with constant non-zero velocity in the +x axis. The veloc/k )u zdl+-4q8ap cech w(a6fyttu/ .jity versus time graph of this object iaack-w.dey p jtu/l cf(4+6h8utq)z/s

  An object is moving with constant non-zero acceleration in theim0l z5ncpy23/ 6oynl,k 3vsqpz jc7my.1 d5v +x axis. The velocity versus time graph of this objec lyq1,y/30 2kynzmj d cp7n zl .mpso55cvi36vt is

  The slope of a positioz0zltw +jeo5rh-sgw1 ,+de7 e n versus time graph gives

  The slope of a velocity 8 irheh/8.wy g6ci:h:nry( +qw;wydrversus time graph gives

  The area under a curve in an acceleration verz w6b:bzfx+.tsus time graph gives

  The area under a curve in a velocity versus time grapgidjrp8y/d hwu, ; -)th gives

  If the position versus time graph of an objectqnp:lor-a /t2 is a horizontal line, the object aql: -ro /npt2is

  If the position versus timaqepq,w,j .i2 r;t r o,;l3kwwe graph of an object is a vertical line, the object is;jrqw,,lqwr ei,k.opw3 at ;2

  If the velocity versus time grapi29/x tw b1kl lu4iry;h of an object is a horizontal line, the object isit1lli uy; bk92/4rwx

  If the velocity versus time graph of an obje7gxpmr4ql+n 0 ,g ig0wct is a straight line making an angle o4+0gglp0w7rq mxi gn ,f 30 degrees with the time axis, the object is

  An object moves 15.0 m north and then 1fkts7b1u36sa 1.0 m south. Find both the distance traveled and the magnitude of the displacs ftaubsk1736 ement vector.

  A boat can move at 30 km/h in still water. H.20hqlmt vb(now long will it take to move 12 km upstream in a river fnhql.tv mb02 (lowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 16 1zguz 3-rmr k b:7*ed;ba8fin09 m)

  What must be your avera v8 rh0*h t,l( ;ttktnyw5i*u3 zpbz+pge speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (r5;a3zo)aavhdi1-(l a7 x ;i rbiai/gapproximately 42.0 km) in 2 hours and 57 min. What is the average speed of ih/vz;75al ;i) xir1ba3 r( gaaio-a dthe runner in m/s?

  A car travels 90 km/h. How long does 8u oea0a4fwl3it take for it to travel 400 km?

  A ly (light year) is the distance that light:nmxset q6d g tr7i;dh t6+.8u travels in one year. The speed of lightdix7ug6tshq + .:6mtr;n8 edt 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 ror4p3c wo t8+vbums8:n.cc b: xad and you look to the side for 4.0 s, howx.c b c m8:nbpt +4ucr8oswv3: far do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 945wdjh v eu u4px3x77om rm0pum4a8a 100 s, your averagp 0 om w3u8vue774a9x4 mdurxh4 5jpmae velocity is

  A polar bear starts at thex -o 7( tmyeqyy(*pdx( North Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km(7 xq(xoyd*yp(ym e- t 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 thef*wh v ws*+e8q North Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km ehq +f **8wsvwnorth, then 1.0 km west to return to its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles. It .yqb00 r(lkoithen starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minu(0iqr0 .oyklbtes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h 1:gxgyloas; he7 (7wzzs(dk.. What is the average speed of the e(sg zkas(x.wzd 1:yh; 7ol7gmotorist for this trip?

  A motorist travels for 3.0 h at 80 km/h v(6ni)cz0 x2x mqb;o aand 2.0 h at 100 km/h. What is her average speedqo)xm 6 ;2azcvbx 0(in for the trip?

  An airplane travels at (5j3jok m(i. 4g 1ibs f2lqijh300 mi/h south for 2.00 h and then at 250 mi/h north for 750 miles. What ish3(foqmk2 .j s j(lbi4i1ji5 g the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 1vr2 tpd) /:;ykuwrr7/6+ki epl6d ri e00 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 the largest lead the team B runner can have when the team A runner:rvwit/k7yredr dp u2k +/r )p eli66; starts the final leg of the race, in order that the team A runner not lose the race?

  A car decelerates uniformly a4b/m7lca4 kfb lhb)ye-tf1pzk8 hlk0o ( mg4;nd comes to a stop after 13 s. The car's average velocity during deceleration was 40 km/h. fl/ok;-41780gb) k b clhbhzml e 4yfmt(a pk4What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 v(v(tusf4mf7tuxu9 e (qqp*9 m/s to 160 m/s, at the average rate of vqmf97est4 xu u vp((u9q*f(t$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accel(ufmt9dlnu sdq,3e ;n t n-c/4erates 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 ta(fik f-rl44if6 1zxaccelerates 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 pbf2 -r,cd,i6s v3t qiup with a constant acceleration oftc fdiiq,3r,s6 vb2-p $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 2.9 m/s experiences a constant acceleration oqa0. /ryq m;n0kloz p(qebz e1(;l,cho pj(y-fey-rob z(;enq(( 1;/.j hzo0,qp 0 kypallqc m $1.6 \; m/s^2$. What is the cart's displacement during the first 8.3 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of/t 9j+eje u6q.rnz( cxi-w sw- 481 m/s strikes a sandbag and penetrates a distance of 6nq-(e-r/ js9zc i+ t.wwe6x ju6.98 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an0ou z;9ock9 wn aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requi;okunowzc 909 res 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves withrzl+o-ei.s,p wx o3 1j 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 a distance cuy c,dn))(soof 200 m. What is its average acceleration?ou ns)d,(cc )y

  An object starts from rest and undergoes uniform acceleration. During the*dt6cc:r x;ea vb+ cz5 1wn6iy first second it travels 8.5 m. How far will it travel during the third seco*6ct vin15x +c :aey6;rwc zbdnd?

  An object is moving intl09f,fpa hp y 337qvbu-igs( a straight line with constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this t (7g hil0bqa3v-pfus,p9y3 tf ime?

  A car starts from rest and accelenhkf6oe7 b67hrates uniformly at $3.0 \; m/s^2$. A second car starts from rest 6.0 s later at the same point and accelerates uniformly at $5.0 \; m/s^2$. How long does it take the second car to overtake the first car?

  A car with good tires on a dry road can decelerate at about r fn49 jhtu)f* 2-lofzo1mcm:y /1lyg$5.0 \; m/s^2$ 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 lj 3z-no*3 shzxight turns green, a car that has been waiting at the intersection starts ahead with a ch33xn ojzs*z-onstant 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 spee1;n-9btm)0 2uw n cy8*qufimcvmsa9t d of 12 m/s on the surface of planet X where the acceleration due to grt*fs8t 90)v ym- c 12n;9miuca mnbqwuavity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward wi.suvu7w q 3vva/-tx j:th a speed of 12 m/s on the surface of planet X where the a7j/:vu-.xav twv3 squcceleration due to gravity is $1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

  An object is thrown upward with rns 4 d6(tq35 2*g p-lpnhqfvqa speed of 15 m/s on the surface of planet X where the acceleration due to gravity i2rp fl6qgv (nd*ptsqhq n54-3s $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

  An object is thrown upward with a speert3d 1kci1k)d d of 14 m/s on the surface of planet X where the accel)3k t1 rdidck1eration 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. Ifq jv76j(nj 0 kdgwv8wx/ra e)k 6y1rp, your friend holds a ruler between your fingers and releases it witrawv/wv, gn 0qkj7d k1)r8py6( xj6jehout 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 )b:tk)y 8)vi lybo sd*is its velocity after 3)vk8sob *yylti)d : b).00 s?

  A bullet shot straightapyfd)// xw-a up returns to its starting point in 7 s. What is the initial speed of the bullet?dy//a px -w)af

  A ball is thrown straight up with a speed of ja,qo4n* kqiam) ;7 4q/jmxv-pv ycn;36.0 m/s. How long does it take to return74o4vq)amc;;-* y ,/nj njqxvpikaqm to its starting point?

  A ball is thrown downward from the top of a buildinzle bd2/vlpy4 j(lln9 *,fjl48yiem,g with an initial speed of 16 *lbz4 yyf i8ejdlm2 ,4l(/nvlp j ,9lem/s. It strikes the ground after 4.5 s. How high is the building?

  A ball is thrown straight up with a speed l/uxfg4d3 uddsj10+d of 30 m/s. (only fill in numerical value in the blanks)f x3/+gdld10jdud4su
(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 inv.b-zari/yk) ei5jkc l5ng(*to the air with a speed of 43.2 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 3 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 6 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 6.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocit;q z4bpbhwx m;/ 1yqm7y at t = 1.0 s?

  In Fig. below, what il ;5 lwn9j21k eljl8wls the velocity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0 sre:c) i(kyh(:nqdb + b?

  In Fig. below, what is 7gzs1 u1pb ,cnthe velocity at t = 5.5 s?

  In Fig. below, what is rqp xjs9*k 3x5the average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity u+. )ksp yqd-cfrom 0 to 6.0 s?

  In Fig. below, what is the acceleratikv9 obin l 3pb-cz es2)g*x3r,on at 1.0 s?

  In Fig. below, what is the accdkd8ei f2tt,i9al(v*stk 48* /l fpnbeleration at 3.0 s?

  In Fig. below, what is the average acceleration from 4 orj9p 0mswql8c87 xz0 to 5.0 s?

  In Fig. below, what is th wquea-o-y8 4se average acceleration from 0 to 8.0 s?

  In Fig. below, what is the d43kkkt*do:tj; ba id;isplacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {spee *ucrigg.+ mfekrlf1:s 9s6:7izrt i0 d|velocity}

  An object can have a varying fqujdu-c17l3 (4kkag 1u h*gfr va +n4speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration iso+b2611tyss7 mr y bum8yfk:x positive.

  If one object has a greater speed t ;zlx5gggt7:it pp2uzz20 p r*han a second object, the first must have a greater accel2pggt;lr git :uz7205 xzzpp*eration.

  Two cars emerge side by sideprk/(-f ,lac.(g hega 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 acceleras*:3 j 9 jlr,m agktoz1 pet6sn6e;e;ation decreases.

  A baseball player hits a foul ball straight u52kp c;7pt+ q-aw e(o.qo tgyut/;uq yp into the air. It leaves the bat with akq+o( ; /p-ycqt.ut2eto wupy g5aq 7; 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, whn,gmfx;1 f6*dl9hx 5l g.9fdm: ej rnhat is happening to its acceleration, how does it change if air frictilhnxmd; gd6rm,*g1 fe:9f fn9jl. 5hxon is ignored?

  As a freely falling object speeds up, whzs(whye 0 d+yf)*6in3j)cect)q v6nyat is happening to its acceleration, how does it change if air fricth0i )cyjedqz3ys*)tn c6en6fw+) v( yion CAN NOT be ignored?

  An object that is thrown vertically upward will return to ituop(emu5 x *i9ser86n9+ .dm5frdr: n khlg 9vs original position with the same speed as it had initially if air resistance is neglignm d9f5g9es(v 6 xi*d n.r+urko eh:p u98mrl5ible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero accel uh+ckw) rp5( bwa/o4reration at the same time.

  An object can have nonrqe3sdv3 yh (0zero velocity and zero acceleration at the same time.

  An elevator moving from the secogtvh v;7f b/v/nd floor to the fifth floor making no stops along the gvhvv/f /b ;7tway has zero acceleration all the time.

  A rolling ball moves syb8j+,te.zvtle/kxw : /:o yfrom $x_1=3.3 \mathrm{~cm}$ to $x_2=-5.0 \mathrm{~cm}$ during the time from $t_1=2.4 \mathrm{~s}$ to $t_2=6.1 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.0 \mathrm{~s}$ is at $x_1=3.1 \mathrm{~cm}$ and at $t_2=3.3 \mathrm{~s}$ is at $x_2=7.6 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-milej:rcq* .+20)0hywlvqhxu rvd ($1 \; mile = 1609 \; m$) track in a total time of 8.4 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 9qd2m2jh) /vk9 uih- bq8 m away in 13.7 s. It then turns abruptly and gallops halfway back in 4.5 s. Calcu/qh22 h bd vu)-kmiqj9late (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 87/yd)ixoe a2 c6bni a$12 \; m/s$ 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 fro14d0(un nnvv3 r,a7 ,bcvvq) cvnfd ;nm $18 \; m/s$ to rest in a distance of 64 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a spwvcu6+za9x ,r:aem0 ueed of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $3.0 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can b 0kb0-)x +r :9bhzuw3k-mmrt ulskay)urst out of the blocks to essentially top speed about umbu mrb3w l0-+zxh90:-ayktk)ks )r $11.3 \; m/s$ in the first 11.7 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 a lxftz*4(;annw.wby fh l:40e 8e.wmgspeed of $19 \; m/s$ to rest in 4.11 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 .l+jkg q;3az2 gm3elca ge3g +l3zlq;. ca mkj2deceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goingef5y)e96xq/ii5 vj 5( acvio71ztiog $25 \; m/s$ 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 10,002:x .tv9rwcf x0-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then 2:trxwxf.c v 9accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$