Suppose that an object travels from one point in space to anoth(s9fik dnlgn,- i e7l9er. Make a comparison between the displacement and the dk9 ng 7iid(len 9-,sflistance traveled.

  When is the average velocity of an object equal to the instantaneo bhs4,dj8k yrjg3(*3 k .vluutus velocity?

  A new car manufacturer advertises that their car can go ybo;nhk w/lp0p o6 9y5"from zero to sixty in 8 s". This is a descriptionhkp9yl5;/b wy no6o0 p of

  An object moving in the +x axis experiences an acczx3 5pkk0y3wd eleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction)jg0tgk0 eq j*,rh- a-si/0ckr begins to slow down as it approaches a trafficr*sikk/he -0qgcra-jt0j 0, g light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x dire/th+o i1px m59w)scnac(v w .rction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceler ai(1wstcx n9v.) w/phmr+5c oation.

  Suppose that an object is :h 5rtmea/9icmoving with a constant velocity. Make a statement concerning its acctc/a 59i: mhreeleration.

  If the velocity of an objecd;o4w +tlxb3k 2gzj8yt is zero, does it mean that the acceleration is zero? Su2gk+ w ;ybd xtz8lo4j3pport your answer with an example.

  Can an object's velocity change direction when its acceleration is constant?82i5vko hty p; r*lia0*p*d jm Support your answer i* l h*mak pvijp*8;o02r yd5twith an example.

  Suppose that an object is moving with constant acceleration. Make a stateggwwhfx 0 r,9f )hd9t8ment cg),0rh8wwf hdxtg f9 9oncerning its motion with respect to time.

  Can an object have increasing speed while its acceleration is decr2jm1mov0 3mn si( 0cyreasing? Support your answer with yo3s jimm(1mn r020vcan example.

  Suppose a can, after an initial kick, moves up alu:r ;briq.sc-l0hc) q 7 (tfnrba48ndong a smooth hill of ice. Make a stateme7nria t d-ql0cr;hnu( 8qrbc4s b) f.:nt concerning its acceleration.

  Under what condition is average velocity)5p/ d+da kiobtno,8 w equal to the average of the object's initial and final vela+ )nod ikwp d5t8/o,bocity?

  Objects A and B both start at rest. They both accelerate 67kttcl . s/pkat the same rate. However, object A accelerates for twice the time as objetc/l k .p6kts7ct B. What is the final speed of object A compared to that of object B?

  Objects A and B both staubd67+s hpfn,rt from rest. They both accelerate at the same rate. However, object A accelerates for twice the time as obnhf7s+6ubdp, ject 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 t7 hoyj4b /w.sx)+piwgnd3-lbq*8ys t he absence of friction, which of the following is truebdys3 wh8+n /7q.igobw ys*t 4x-pjl) concerning its motion?

  When an object is released from rest and fafcho ,81xxp w(* l8u-qwsh+vnlls in the absence of friction, which of the following is tr-8hl( ,sopfvx* 8c +1wxnhu qwue concerning its motion?

  Suppose a ball is thrown straight up. okaw)vm*t,g wd -kvy8,a8, dxMake a statement about the velocity and the acceleration wkdvw,d ,ay,v)m8go atx-*8wkhen the ball reaches the highest point.

  Suppose a ball is thrown straig384nkjw7ma6u3hru4lni (o p n ht up. What is its acceleration just before it reaches its highest point?aju r3p3 lhun4 wo4imk867(nn

  Suppose a ball is thrown straight up, reaches a maximum height, :rul 9 6j5sd87b np6wetjaespbs85 t3then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is going tns s pa:ptedub89w6jel b576sj 58r3up.

  A ball is thrown stra3 1 rk5wrwc(wdight up, reaches a maximum height, then falls to its initial height. Make a statemen3w1 wr r5d(ckwt 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. Mrk+ mnrcfjyq 6lisr(n3.a 6p::;1pwtake a statement concerning itc r ;.wy m:+:nalr6r 1ftn(6s3kppjiq s acceleration.

  Suppose a skydiver jumm4(:aoxh55 .j ;njfz2j jo7lpft*b9omv rdo:ps from a high-flying plane. What is her acceleration when she she reaches terminal :oh(o9zb ofnt;5* 7 lpjm5f.oa2r jj4d j:vmxvelocity?

  A ball is thrown vertically upward with a speed v. An identical ;8s:m m(o lse qo 3l+aganu4d1second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the :lu84 q 3+(mslonsaead;mo1 gmaximum 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 building. One secon 7i(/ek/g itks *kxhfsq2d-4 ad later, ball B is dropped from thgaek/ft7ss2i/qd hx-k4 i *(ke same building. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One second lapgb-s nes1qud52ees pzr 6 )0/ter, ball B is dropped from the sa1up r5/ szp6de qgn sbees2)0-me building. As time progresses, the difference in their speeds

  Two objects are throfv:o /w s ;w7t48fvx)mvhwy(wwn from the top of a tall building. One is thrown up, and the other is thrown down, fh/:;wow)8fwy v m(w 4vt7xs vboth 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 throlxkvb::-q ;dp (5jecfwn straight down from the same building. They are released at the same time. Neglect air-fe::qxjlvdbp ( c ;5k resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The positi 9 ylf4xjrz:lmt6k41uon versus time graph of thuj 1z4k tlmxr4l :96yfis object is

  An object is moving with constant non-zero acceleration in the +x axup0h2 jj)i q+qg.t/cvj+ 0ycwis. The position versus time graph o ycuit+cq)v2jq .+jj/ h0p wg0f this object is

  An object is moving with constant non-zero velocity in the +x ae.pqe6 de2uh 5xu1yi/ ,x,;kd1d wuetxis. The velocity versus t;kdue.2t/ep5x,uyde ,d 1e wui61 xhqime graph of this object is

  An object is moving with constant non-zero acceleration in tirihq(1;5)1zh2hu a e)x tx 3qjwfm) rhe +x axis. The velocit1f)i)rm i2 j)5;zq(e wxrthh1 u3hax qy versus time graph of this object is

  The slope of a position versumd-be-gly/ lul9,(z w s time graph gives

  The slope of a velocity versuslc6kyzrfcv*.y)t ) 8*+ibo dv 8o8bur time graph gives

  The area under a curve in an acceleration versus time graph giv7edzp tn:/a5h( oa/nhes

  The area under a curve in a udwvo-;8h 9ui-4lkgs5 4bgctc ,xh ;w-mezb7velocity versus time graph gives

  If the position versus time graph of an object is,/n4mg fco .(ad w79zs,fyafw a horizontal line, the object iw,/w (yzmc f .,fsdn479gaa ofs

  If the position versus time graph of an object is a verti)twh.jh3g-tstx9 d4c cal line, the object isct9h-wxgtd s 4h.j 3t)

  If the velocity versus time graph of an objc*d)bpdn/rc s;1; ab oect is a horizontal line, the object is1)bo;cns/ pd da*bcr;

  If the velocity versus time graph of an object is mx;mdaco1r+yc w7b-v--5g3dtff qzu:1)j fua straight line making an angle of 30 degreesdmgt3 1c5zou br-m-+;w1)7-vqfx j:u adffyc with the time axis, the object is

  An object moves 15.0 m norbt st5y vdl77vt4n3 g5th and then 11.0 m south. Find both the distance traveled and the magnitude of v7lb n5y743t5dvts g tthe displacement vector.

  A boat can move at 30 km/h in still water. How long will it take to move 1 g*v( 4wivyjg:2 km upstream in agi : gvvj4(*wy river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609m1wh7wgp +:f+en , lta m)

  What must be your average speed in oir1:ves :py 4order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. Whatzsk2 qzl-nx zt./296wrgia+w5 i(:f2ar b bjt is the average speed of the+af. zaw2x(rz rbi262i-:w zqst9gnlt/bj k 5 runner in m/s?

  A car travels 90 km/h. How long does it take xkr 3zylo 3*j 1o5fyr3for it to travel 400 km?

  A ly (light year) is the distance that lightdm:mb)bx7:o z travels in one year. The speed of lzm:m 7bbdo: )xight 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 and you look to the v1m6h/hwf4xjxw o 4wbigq.; )side for 4.0 s, how far do you travel during xwj;f4mi)h.6hwog4w/1qxb vthis inattentive period?

  If you run a complete loop around an outdoor trat)ukx13vjc*ce b2 ffo ;,gw,nck (400 m), in 100 s, your average veloco g;,*f bc jn1ewcvfu, x2k)3tity is

  A polar bear starts avqo4-6htlg,at the North Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km gqt,vl a 46ho-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 1.0 km south, then um w /(82b9pu8akelol 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. This / wmb88 upellkao29(utrip takes 45 min. What was the bear's average velocity?

  You are driving home on a wegn)m an;0/*hh5 wqi s4ju88 s(4dfk-iwl kqd bekend from school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15q(8a / lh)84nqkims;0wskhgf5 -u dwb*jd4 ni 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 -ye38 stasxn/sy22aqi um 70waverage speed of the motorist for this trnseys0 t -7usim8q /yax2a3w 2ip?

  A motorist travels foroegs gw .)n: dls1)eu, 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her averagegw,.s unl1g) doe)s e: speed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h nor8 tthd7 nmyv87tnan/4th for 7504 tn/ta7nv8nd7 y mh8t miles. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person 10.4ygw ngllttso g2 9who 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 100 m in 10.y2.4 g1gtwosltg nl9 01 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 e/b;p9ip vs7 bgp6j y:5ooqwrj 2.hp 5after 11 s. The car's average velocity2y p.r5bip97pbw;5eqgovhops j :/ j6 during deceleration was 61 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the averag*pd )xaymt8q wj+ 6s.he rate of )6tjxpmq*8+h .sady w$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accel5 0 *xy3gxxz3ryh ciqc- 5gzu7erates 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 acc 3lw1 tt,h*hryelerates 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 sp6ec t 2vuch j*fow7)5w ql8o *uv)o2mreeds up with a constant accelerationtwfu jqu6o o8c )7w 2*vo2 l)5ve*crhm of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 1.4 m/s efpx. 2pn y0yr/xperiences a constant acceleration ofpnp. x2/ yyr0f $2.3 \; m/s^2$. What is the cart's displacement during the first 7.2 s of its motion?

  A bullet moving horizonthem0k 3:rdi9pally to the right (+x direction) with a speed of 230 m/s strikes a sandbag and peneek3:ihmp09r d trates a distance of 90.14 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 carrier.i1f)( ilou;j7d-t+up h/ury q It reaches a speed of 42+ 1 piftu q;/j7i-)lo( hudyur 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 accelerationb:2n8 * ahm:rvm0yf/fsmu .euign1 7 z 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 200 m. What is its oa0 j3mfr22mwd k45dcin 8l -n*dy6bdaverage accelercbmnwy0*4 l-d 3fnmdk2d j2d6a5ro 8iation?

  An object starts from rest and undergoes uniform acceleration. rmtgdra7,9+4 u+af on0dei 3i np4go 8 During the first second it travels 5.5 m. How far will it travel during +dinonaf4tm 4e83r g9g, pi0+d7rau o the third second?

  An object is moving in a straight line with constant accele+sw-, s2)b 00 qk)oic+kv ,accpwsohqration. Initially it is traveling at 16 m/s. Three secoc poc 2 v s+0,wiwbq +ok0hq-s)skac,)nds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates un5 obgo)- f3;r7mye3rjv. feuziformly 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 o0x4vvoi9a l-nn 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 traffic light turns gva+ z)dwnaa (uu72sp7(z )lxoreen, a car that has been waiting at the intersection starts ahead with a constanpaz (vl +)(zw ns7u)a2a7 xdout 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 speed2(y0jglb guf)4h2j ls of 12 m/s on the surface of planet X where the acceleration due to g blf2j )g4l(2hgs0 uyjravity 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.8:8vcor vztvky * m9v36yxaha pv4-y /s on the surface of planet X where the accc8a8 yv y*tyr:vao v4vzkh9.p v3m6x-eleration 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 a speed of 15 m/s on the supscb - wu/8/ 22odmwlurface of planet X where the /2d8-olups u 2wmc/b wacceleration 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 14 m/s on the surface of planet X wl s/+l+w;toc zt;vtxv (- s.gdhere the acceleration due tow/v(+zst.l-;cl gto ;tx +dvs 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. If your friend hodss x4c+4 8qtxlds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fcxd q8s4+t x4sall before you catch it?

  A ball is thrown upward at +aad7:ipus-qiwv .7c a velocity of 19.6 m/s. What is its velocity after 3.00 .7d7spa +-cqaivw: uis?

  A bullet shot straight up ret vc8w0unmc)h- urns to its starting point in 8 s. What is the initial speed of the bul cm0)-vchwu n8let?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does it takey,5qx wj92v(jv u 1tse to return to qevs9jw5j y,(u1xt2v its starting point?

  A ball is thrown downward from the top of a building with an initial speed,z4a.wurs) zg of 13 m/s. It strikes the ground after 6.6a.u4wrs,z ) gz s. How high is the building?

  A ball is thrown str4dhd-kine9rfmv,3 /e aight up with a speed of 30 m/s. (only fill in numerical value in the blandvee4i n h ,rf-9kdm/3ks)
(a.) How long does it take the ball to reach the maximum height?    $s$
(b.) What is the maximum height reached by the ball?    $m$
(c.) What is its speed after 4.2 s?    $m/s$

  A foul ball is hit straight up into the air with a 4+* u -dbordzbb;mnt.m.hnx6 speed of 35.9 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 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 velocity atr6 zrngyzg7grr+ /7p7 t = 1.0 s?

  In Fig. below, what is the v rpw*0*sewm-5;k 0mln- sq i1jcov1apelocity at t = 2.5 s?

  In Fig. below, what is the velocity at t = gxujpt/2u 8*f 4.0 s?

  In Fig. below, what is the velocity at t = r c9y-h)wabn7 5.5 s?

  In Fig. below, what ygvj2(p2b-w7u b6frf is the average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity from 0 to gxl+xglse2(c/ v)q bjbd-;y) 6.0 s?

  In Fig. below, what is the acceleratiyor(k 6ryget6lm0wn1d y-4bqc0 d-7 yon at 1.0 s?

  In Fig. below, what is thex77c4.n*uoanuknw j zp(n:cp8db0 q ecy:)x 7 acceleration at 3.0 s?

  In Fig. below, what is the average accr84 zkevd *wsv kd5x// p*a-lweleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 9ulzcy/8u1hoto 8.0 s?

  In Fig. below, what is the ekug obeor ;:0p. )-cudisplacement from 0 to 8.0 s?

Does a car speedometer measure speed, veloci+ dh*8xv l mphblr2a9slq9 )*bty? {speed|velocity}

  An object can have a varying speed if its vdzgc,)u -0 m8wh7o gqywmw( l5667mcegfu j,zelocity is constant.

  The velocity of an object can be negative wh jq7pfps 2jcs)1ccjn:*36r5y00m jroe+c po gen its acceleration is positive.

  If one object has a greater speom/ch8 3 krmx260 tpkked than a second object, the first must have a greater acceler3x2 h6kpcmokmt /0r8kation.

  Two cars emerge side by side from a tunnel. Car d:sel( otsum gp z-e:,36u,e*ddat7gA 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 ism51h9,+meq(ca mo qy n speed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It leaves the bat wj epvc/be6 4j9ce.: nvv48ygwith a sp.gew:j9e/ yvvbn4 8j cv6pe4c eed 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 its acqi0g *xec myag3)(cab80* qaa celeration, how does it chacm a0ax*aeqc)gyb g*3(q80i ange if air friction is ignored?

  As a freely falling object speeds up, what i2.m32ee)vj imaw3r baw0or a c; :wo+os happening to its acceleration, how does it change ifa3m0r 2aajiob ev.) ;m2r3cwow w:e+o air friction CAN NOT be ignored?

  An object that is thrown vertically upward will return to ibbzlqf 5s, 1 5m*ty5pdts original position with the same speed as i5fbbzp*15s5tqml,d y t had initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration owz 2yihvjb* :*b oh(8j tsu2-at the same time.

  An object can have nonzero velocity and zero acceleration at the same tidjp(x b +t +lsjt0*5vome.

  An elevator moving from the second floor to .* mt a 53x:fexg;mzz*sq -cn)aoit(ethe fifth floor making no stops along the way has zert exq(nm:5z3** emx)gct;oa.z-a isfo acceleration all the time.

  A rolling ball moves f jxvfhx73),hinta )o2n1n ubv,kx 8wz*os17hrom $x_1=2.2 \mathrm{~cm}$ to $x_2=-6.8 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ to $t_2=5.5 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.0 \mathrm{~s}$ is at $x_1=2.9 \mathrm{~cm}$ and at $t_2=3.4 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps arouwpzh*nr5j9 arjs4 t* 2nd a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.4 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters awayyu;vgxq;) dvj kd /-2e from its trainer in a straight line, moving 93 m away in 8.0 s. It then turns abruptly and ga-/q)vejy;vgx;k ud d 2llops halfway back in 4.8 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 fr o1.x6hibjjj3yq 7cn-om $11 \; m/s$ to $24 \; m/s$ in 4.1 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 l dqf 2i ):sy7+v6ynsq$16 \; m/s$ to rest in a distance of 68 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a hwozkd3 v13t )speed of $28 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.8 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top spp4 mcv9fjn2zp y,:,xlum9yf 1 eed about m y v1p9 xfz4ufyjc:pm,9 nl2,$11.2 \; m/s$ in the first 10.8 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 speed oohd 90981s0g ry9xxd zjhmf/cf $15 \; m/s$ to rest in 5.99 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leavesq5syjn(j1 k *j83ecg5a4d g yi skid marks 92 m long on the highway. Assuming a deceleratioe5g qji(k38cn5dja yys4g* j1 n of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goin bw+nu**kvv*z 1xkab3 g $25 \; m/s$ 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 in less than 30.a;ul,25zid m ho-cgi r35+r bu0 min. After exactly 27.0 min, there are still 1100 m to go. The runner mhd5c ruu,mzbi 52i;lago+ - r3ust then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$