Suppose that an object travels from one point in space to another. Make rlis0nj 1 m p(*b;1tyna comparison between the displacement and the dista(trb;y l0j npnms 1i1*nce traveled.

  When is the average velocity of an object equal to thh4rg.: ir owv;7tq2n2q+htgoe instantaneous velocity?

  A new car manufacturer advertises that their car can 0c.y; *hovm3 ev7jdcvgo "from zero to sixty in 8 o vy7je .cmvd; v30*hcs". This is a description of

  An object moving in the +x axis experiences an accelea.cxy5hx oecv*))3frma 3 fe* 0 ul-dnration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East +o )mtf.a ;k0okui0tt(+x direction) begins to slow down as itot0ta;ofku+) t. ki 0m approaches a traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (ty2demi,,tcrm: m 1s 5-x direction) begins to slow down as it approaches a traffic light. ,tm1y mrs, 5cm:ed2t iMake a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statement 4l4bjjs: wz 9rconcej4s4wjz:brl 9 rning its acceleration.

  If the velocity of a9.d7, /cxl1ce kjdl zkn object is zero, does it mean that the acceleration is zero? Support your answer with an example.ljzk.ck9 7 x1 lddec/,

  Can an object's veloy ,e8i i7xr,ovcity change direction when its acceleration is constant? Support your answer with ai8, 7er, yvixon example.

  Suppose that an object is moving with constant acceleration0,pznm 7zaqd0fh d,v)s ee72 b. Make a statement concer 2d)z7h,fqm ndvspeab ,7 e0z0ning its motion with respect to time.

  Can an object have increasing speed while its acceleration ip 7 wblov0ew8k0o ,-cz gpy*-ls decreasing? Support yo-p ey*,oblwkgwzl 80o-v70cpur answer with an example.

  Suppose a can, after an initial kick, moves up along a smooth hill a02kfe5m-tavp q b*xs7uj;h2 of ice. Make a stue5vk2hs tbm -;0f 7xp*aj 2qaatement concerning its acceleration.

  Under what condition i/s/vf:0p7 fius 3tdo os average velocity equal to the average of the object's initial and finals:o/u vi p3/fods07 tf velocity?

  Objects A and B both start a5n5/ udp5a r2uag 3 9xuz;biect rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the fi55g3 dx u zb9r2paen; 5cuua/inal speed of object A compared to that of object B?

  Objects A and B both start from restvlz4t v9r)krq axxm zh. w(w9h. 2)n6q. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A comparedw 96.m 2lx9 vw)n)z.rqzq(h 4ahvrkxt to that of object B?

  When an object is released from rest and falls in the absence of friction, whichn,g a5y i7wx-ma:ws4h of the following is true concerning its motg7h m:-yxwaw s,i45an ion?

  When an object is released from res; - rr.qfhx g0xk)yxl/ ;msd8jt and falls in the absence of friction, which of the following is true m ;- 8slrj)0fkr. /xd;qxgxhyconcerning its motion?

  Suppose a ball is thrown straight up. Make a q+ 4:ou f/t(aevsz. pqstatement about the velocity and the acceleration when the ball r/up4tq eavzs (f.oq:+eaches the highest point.

  Suppose a ball is thrown .hkgd8i j4jqi8 d/yxaz*: 5rpstraight up. What is its acceleration just before it reaches its highest dqa :ijph84.k * yz58/rjgidxpoint?

  Suppose a ball is thrown .e pax3kft/8/wp9kmxvv7.lnxhhh7 0straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball /07. e pl/ak3hmxv8.7f wxh xpvnht k9is going up.

  A ball is thrown straight up, reaches a maximum heighutsl xh,d :shz, ,ljwnb.b8 *9t, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the* s9ld, .x,s hnt:blzwub8h,j ball is coming down.

  Suppose a ball is thrown downward9l74j yjgho++t ko1wukif l)lq4 wt-8 in the absence of air resistance. Make a statement c 4kjowgk w8)o9 t+jt7+iulqllyf41 -honcerning its acceleration.

  Suppose a skydiver jumps from a high-flying plane.ytsf7efq- 1wth5 n+j - What is her acceleration when she sh+fh7ys tqwf1- t5 enj-e reaches terminal velocity?

  A ball is thrown vertically upward with a spowt0n(n 1k /;eewacj j91d r;reed v. An identical second ball is thrown upwet1;;c(koa/ wn9jr1d n0jw erard 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 thek uq-7i;plih:.1x.t5 zydo nt top of a building. One second later, ball B is dropped from the same buildih-7iyk1 xt:pdl;n. t5ui oz.qng. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One sec3h ,xb( ljj4/ izy4ajoond later, ball B is dropped from the same building. As time progresses, the difference in their speeds jiz o/(,jxy3alj b4h4

  Two objects are thrown from the (z. s yuwed0 wumfhdw**4j x*6top of a tall building. One is thrown up, and the other is thrown dowu*6 uzf w4*(jw0ym. eshwdx*d n, 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 seco. i,)lxvzl xnms3+ -oand brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare + zla3lm)s. ,o-i xvxnthe accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The 6kr9 r/n otpx0position /0 ro 9xtrn6kpversus time graph of this object is

  An object is moving with constant non-zero accelervz0bto)ro4 p03 i(tq eation in the +x axis. The position versuvzb 0 o3itp)0q4 r(teos time graph of this object is

  An object is moving w0er)6 3vdy cpyith constant non-zero velocity in the +x axis. The velocity versus time graph of this object isepy603 d)cyrv

  An object is moving with constant non-zero ac1rw/k,v0 zsb cj8c soj7mf l+:celeration in the +x axis. The velocity versus timemj:+ 0lzc/b,ws vcr k7 1s8foj graph of this object is

  The slope of a position versus tim2yx z1za* m kx.v9: t:fmpxri(e graph gives

  The slope of a velocity versus time graph giveop n/d.ht;q*7 c ;:pyzit:wdu s

  The area under a curve in an accelet z7is1r;gm*e +9x/-tfdul xtration versus time graph gives

  The area under a curve in a velocity versus time grabf+wok,c1l c9 ph gives

  If the position versus time graph of ana;v xo(.eezz( object is a horizontal line, the object ( o exeav;(z.zis

  If the position versus time graph of an object is a vertical line, th43umjda1vzw2o7 oap) e object ispd7a1 3ov wm)4ouzja2

  If the velocity versus time graph of an object is a horizontal line, the obj gzz3pbh12gmk3nmq(s q u, e3vxx;:0hect i;2,31zmz xg3g shqpqe(km:xv 3u 0hb ns

  If the velocity versus time graph of an object is a straight line mn4v 3v:p ij+ddaking an angle of 30 de nipv:j+4d 3dvgrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both the distance tra8n2vxvm/ w u:x nu*bqp52 q;hjveled and the magnitude of the dis:uxmbxw/;58j 2vuhvnnp*q2 q placement vector.

  A boat can move at 30 km/h in still water. How long will it take to mo;d-tvgh d3 fi6pc1+re ve 12 km upstream in1r+g3;hi 6epvd t-cfd a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi =e-wzyd8 c)q1g tg.eq 3ct5)sm 1609 m)

  What must be your averag hsua+o k73k7ueydlz6 8j91 lie speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 m5c 6)rb0ha6p9hzr ker/ltz zg6u3sy5 in. What is the average sp rhbchlt/gk0 6yr9 )eaz63 6zpr 5sz5ueed of the runner in m/s?

  A car travels 90 km/h. How long does it taoa ,2)et 8 ovq8l7(8dnjx rfjoke for it to travel 400 km?

  A ly (light year) is the di; zizdx8uf9+pstance that light travels in one year. The speed of light fxz d+8izp9;u 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 side fo, vvt9 fe*f/+hag(g+cpz*a6t 9sv cmqr 4.0 s, how far do yogz(+a f, p /aqs6ve+v9 t tm9hg*fcc*vu travel during this inattentive period?

  If you run a complete,/, 7dxrmnvd, utidb 2 loop around an outdoor track (400 m), in 100 s, your average ve27,rxi,uv/n bddmdt,locity is

  A polar bear starts at the No i 4viyuzwk*x -6c7kbbj,) b kql,nyt*ki.z; /rth Pole. 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. Wh ,*.zy,qlyxi-6b)wi7zjvc ; k4tkkbi/u*n kb at was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 *om71h:z q du,zf opd*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. What wah p:z f *,1zmdodq*uo7s the bear's average velocity?

  You are driving home on a weekend f97, vdqpp q( be6i2ehbrom 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 15 minutes. How far is your homeb 9bp6eh eq (2,qpiv7dtown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. What is the ave;v .t:f4eilsn rage speed of the milef.st v;4: notorist for this trip?

  A motorist travels for 3.0b k.) i:darropt,7sy +;kitq/ h at 80 km/h and 2.0 h at 100 km/h. What is her average speed for the ty/ka)it, s.r i o:dk;7pt+bqrrip?

  An airplane travels atgme 6krb+f4qjjs,- 0p 300 mi/h south for 2.00 h and then at 250 mi/h north for 750 miles. What is the averagef-jrqk4g,b0 m6js e +p speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 pd)v:y dxs0 8ra*+axiy9 +nvr 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 starts the final leg of the race, in order that the team A runner not loseay*y +8 adxd r9+iv0xrp )nvs: the race?

  A car decelerates uniozdtc,k.9,,e a vhweo:azo )5formly and comes to a stop after 8 s. The car's average velocity during deceleration was 60 km/h. What was the car's deceleration while slowing down?v5, oz,caow dheo. ea tk)9z,:

  An airplane increases its speed from 100 m/s to 160 m/s,p19oyp: zmugq z+/om ; at the average rate of ogz1p9y: + ;p/oqmzum$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate6,h.tih z,0rufax l9 j 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 w1.2; mmdu2*v)kfb( khrex (i c,tls,p(rkig accelerates at $4.0 \; m/s^2$ for 5.0 s, then maintain that velocity for 10 s, and then decelerates at the rate of $2.0 \; m/s^2$ for 4.0 s. What is the final speed of the car?

  A car travels at 15 m/s for 10 s. It then speeds up with a co(khmo5e p v69anstant accelerationk(oe6 mpa5h 9v of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocitrm xw(r9j(pxg2 4q0ovy of 1.4 m/s experiences a constant acceleration of (rxp49jxog qw 2(r 0vm$3.3 \; m/s^2$. What is the cart's displacement during the first 5.4 s of its motion?

  A bullet moving horizontally to t u9mgbk9y-z z:o(+nde he right (+x direction) with a speed of 537 m/s strikes a sandbag and penetrates a diszu g-9(d:b9km ey+nzo tance of 42.10 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on uxk4e ;8kinc vf.yrw3ry-11q 0 fqfj;;mhu7ban aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming th uunv;cr1 hw f;f7kk;3qe 8ji q1m0 fr.4yby-xe acceleration is constant, what is the length of the catapult?

  A car starting from rest movesu;f2x r.v )vpop;wv)u 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 rerhk3j6 p 3:d*dajs2in a distance of 200 m. What is its average acceleratiors3 d2hde :6rkaj*3j pn?

  An object starts from rest and undergoe-kl g0 ayu7g5dppk9k.s uniform acceleration. During the first second it travels 4.1 m. How far k9uy5- 7lkpkpg.0dag will it travel during the third second?

  An object is moving in a straight line f5crzgmy 0p58with constant acceleration. Initially it is traveling at 16 m/s. T cg8myzprf055hree seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates uniformlyl(xz hsb.d5 : gs5b-zr 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 a y*o -l8eoz)nft 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 gre) 21utz z*zh:(x5zlq8mqmzdhen, a car that has been waiting at the intersection starts ahead with a constazm tm 8*uzqhlz1 zxq)(2dz: 5hnt acceleration of $2.00 \; m/s^2$. At that moment a truck traveling with a constant velocity of 15.0 m/s overtakes and passes the car.
(a.) Calculate the time necessary for the car to reach the truck.    $s$ (only fill in numerical values)
(b.) Calculate the distance beyond the traffic light that the car will pass the truck.    $m$ (only fill in numerical values)
(c.) Determine the speed of the car when it passes the truck.    $m/s$ (only fill in numerical values)

  An object is thrown upward with a speed of 12 m/s on.9/g8go6 mej1p6 urhaj6j w- lpxyu; b the surface of planet X where the acceleration due to gravityo;8lj-. jg/6mrap u e6g169ywb u xphj is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with 9:xk9rpu1r di:2ijcda speed of 12 m/s on the surface of planet X where the acceleration due to gravity is 9x92:ik :ddrjcr1ip u$1.5 \; m/s^2$. 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 ocm 9jbqnj-;*43;r.d b d daypof planet X where the acceleration due to gravityyb*3.nqdb;rc4 9jjp ;o mad -d 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 spee4uvlpgf. 2- 0wz pbfz/yj,rk/d of 14 m/s on the surface of planet X where the acceleration du4 f/j.fp2zb/gp-,uyr 0zwl vke 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. If yot qinx.7*b :quur friend holds a ruler between your fingers and releases it without warninnt: bu*xq7i.q g, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upw+ht9c;wx culd l8uny w3.t++kard at a velocity of 19.6 m/s. What is its velocity after 3.0ncucu3 wd+k xhl9 t8 wy.;+l+t0 s?

  A bullet shot straight up returns to. -cbwvk5 j g*hi,/cxx us3uuo2x)*p b its starting point in 7 s. What is the initialhx .5px jb 2vu3g -i*osuk)b/ x*c,ucw speed of the bullet?

  A ball is thrown straight up with a speech5in l) +uvin1q4j.n t28plvd of 36.0 m/s. How long does it take to return th. tpijln)qi4n+c1n52 lv8u vo its starting point?

  A ball is thrown downward from the top of a buix 1j1.,ct(lwp6emclmxhg n.6lding with an initial speed of 13 m/s. It strikes the ground mp, t 6hjw6cx1.l1n xcmg.( leafter 1.2 s. How high is the building?

  A ball is thrown straight up ;8:8 u h uvwimqg7jxm6with a speed of 30 m/s. (only fill in numerical value in the blang88u 6wqj u7vi:mmxh ;ks)
(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 ilal7q 1u 0;clszq/n6pyn-w :rnto the air with a speed of 47.3 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 14 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 14.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity a *vb6*j v tx:vk0hapw*t t = 1.0 s?

  In Fig. below, what is 9t w*,cc 7jedethe velocity at t = 2.5 s?

  In Fig. below, what is hryyt1 (de;j/vra5 )c the velocity at t = 4.0 s?

  In Fig. below, what is thec gjivdw5a x(,x5)gj, velocity at t = 5.5 s?

  In Fig. below, what is the qxu:j 8;weee0* ly s.laverage velocity from 0 to 4.0 s?

  In Fig. below, what u;phmr df 4 4g1ok/rpae90x4 2g ford/is the average velocity from 0 to 6.0 s?

  In Fig. below, what is thqb5f(3tqp/o g e acceleration at 1.0 s?

  In Fig. below, what is the accevo83x ktz*yjr5 vr s90; uc+bzleration at 3.0 s?

  In Fig. below, what pni+vlqcdsg-9 w;n, ffg;n /+is the average acceleration from 0 to 5.0 s?

  In Fig. below, what is the +zegac.,v92tj st * fpaverage acceleration from 0 to 8.0 s?

  In Fig. below, what is theap.*j k;r2 aov displacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|veloc u pwa2o(- tr8)dxbh4pax:7 nsity}

  An object can have a varying speed if its velocity is emwcaab;t1l a1g h;kad. tj2y r)1 4w7constant.

  The velocity of an o1.y gwsbkd-3 i)n7cdw ;xu1mybject can be negative when its acceleration is positive.

  If one object has a greater speed than a second obji* 8v1z(qfrjjw 4zvi2ect, the first must have a grvjj 2z8rvf*4zi qwi(1eater acceleration.

  Two cars emerge side by side from a tunnel. Car A is traveling with a spee,)hb i.fzwl q0qpu 8otbj 2f83d 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 c8go *m4hc7k4ncdq :wl/w)l has its acceleration decreases.

  A baseball player hits a foul ball straight up into t5gw5 ;rm-o4b/ke zrzl*ad f) qhe air. It leaves the bat with ar/5 b mw k*4;oaq)ref -lzz5dg 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 to its acceleration,omo :zx,cr/h 1 how does it change if air friczm1orc:h/ ,oxtion is ignored?

  As a freely falling object speeds up, what is happening to its acceb8cg ,v1j; mj6b iwdk6leration, how does it change if air friwgmc6b8 v,;d i6 1jbkjction CAN NOT be ignored?

  An object that is thrown vertically upward will returo 4g5ku)*lnzkdr l( ehgmw2n15 m: w)jn to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this res)mu gg5onmld:ek(n2 )zw5*lr kh41jw ult be altered?

  An object can have zero velocity and nonzero accelerati+y2 .es ijil;9l xbzk+on at the same time.

  An object can have nonzero velohgmfdl39wyv:ckd 6765f6( lfzb86 v 9iu oad mcity and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor making no stops alonyr39pcy tblkh5c x xjdf,oor(;2jol4 -+f ;6xg the way has zero acceleratior;o(l,t 3ox2-pjl x4dh9; 5r ykofy6jcx+fcbn all the time.

  A rolling ball moves f mzfh9u(c7s-d:nhn1 arom $x_1=3.0 \mathrm{~cm}$ to $x_2=-8.2 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ to $t_2=5.2 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.1 \mathrm{~s}$ is at $x_1=3.3 \mathrm{~cm}$ and at $t_2=3.4 \mathrm{~s}$ is at $x_2=7.9 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete z r-:dz2x k)b5s 8jtqrt1rkbj )iqm bw-z;u2: laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.3 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 113 m awajt6 yvan 1ttb(s,,g q2y in 8.8 s. Ijq,s gbt1 ,yt2ta n(v6t then turns abruptly and gallops 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 frrbb tax9y,m.u d*f-)lom $13 \; m/s$ to $25 \; m/s$ in 4.4 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 t; 53vfl. eavi 38btl;h5ml mi$16 \; m/s$ to rest in a distance of 70 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must rg m+1wu*yh+voeach a speed of $25 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.9 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speed (kxjc+q ,hz3h 0zo7v 9ujemyw+hi 5w, abouzz0 m5h kyw+,ji,(xc+3evhuwh79 jqo t $10.5 \; m/s$ in the first 14.4 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 of yxx p-d;,;ac w$20 \; m/s$ to rest in 4.78 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid m cpxvn/lo1pa4u673t *iv-bk zarks 92 m long on the highway. Assuming a deceleration4 kclub7tx pzv/ 1ivo -p63an* of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck go 0u6 xhom /p( 2kra0w4,v +w.rn5mxqbqfi:vtning $25 \; m/s$ 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 30.0 min. After 6u4z/ ir4o qx//a gvlfexactly 27.0 min, t//x rao4qu /6zfi4lg vhere are still 1100 m to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$