Suppose that an object travels from one point in space to another. Make a 7kh r +-a04 b,euozvkbcomparison between the displac4keaoh zrv -+bb,7uk0 ement and the distance traveled.

  When is the average velocity of an object equal ta+pg-n9 yi/af.h jzg8ur/ za+o the instantaneous velocity?

  A new car manufacturer qgadcael** j(bn m8 .6li5-bkadvertises that their car can go "from zero to sixty in 8 s". This is a description ac*mkjb(5a* 6.eb n8- dglliq of

  An object moving in the +x axis experiences an ac8g2jt beie) /gceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow do*uu7-r.hz wn 2b2o xgdwn as it approaches a traffic lig2zx-w ub*2dh.onug r7 ht. Make a statement concerning its acceleration.

  Suppose that a car traveling to gpf i tn;3p9t6the West (-x direction) begins to slow down as it approaches a traftn p 9;ip6f3tgfic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statead*f0k) 78) wo awdzeus*z dsmh/j w:2ment concerning its *2) kadd*jdhz7/m w e:0s 8zfwaosuw)acceleration.

  If the velocity of an objecteiy, pi3,q;+bl s+4bq ok/ jeej 2kc.o is zero, does it mean that the acceleration is zero? Support yourok eyj2/p3+ b,biok q4 ;j+l ,ci.sqee answer with an example.

  Can an object's velocity change direction when its acceleratyh zqlt0 :u;g5ion is constant? Support your answer with an exa q5uy:g;tl0 zhmple.

  Suppose that an object is moving with constant acceleration. Make a statementnd2yf( uuv b:t/b0v3z concerningdbfvu/(:n vb0t3 2uzy its motion with respect to time.

  Can an object have incr*1 k9p dsib+h8tcaj.czyb)w9 easing speed while its acceleration is decreasing? Support your answer wizcac.dth)pb1sjwb + y9i *8k 9th an example.

  Suppose a can, after an initial kick, moves up along a smooth hill4.qinc)qc*ipo lu gr8x,65nb+ l bn j: of ice. Make a statement concerning its ac8l5g .:nciq+nb jnb6 lr*ci qp,ou4x)celeration.

  Under what condition is average velocity equal to the average of the object', gmd wf:*bf4kyi65fhj6zw l .s initiali6yfdkm *g 5h4:bj f6 w.l,zfw and final velocity?

  Objects A and B both start at rest. They both accelerate at the s 404ykl/vlv//g68ogven zvy vg- su)e l0.l vbame rate. However, object A accelerates for twice the vy0/0 l 48o/sl zee.gyvgbkl4 ugv) -vvv6nl/time as object B. What is the final speed of object A compared to that of object B?

  Objects A and B both start from rest. They bo6q*fva s mzy*l7;9qr uth accelerate at the same rate. However, object A acceleratesq;s 6**mvy uazl7q9rf for 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 ine ozsxqjwr3 ,. it4k dw6,cs9( the absence of friction, which of xsz 4w eq.s cr(j,kw6t3o9id, the following is true concerning its motion?

  When an object is released from rest and falls inm,qzzbhj 4fwucn )3,s:bv-m cc 1w.. a the absence of friction, which of the following is true:4anw cm3vzw-mhj. fcsubz,)q.,b1c concerning its motion?

  Suppose a ball is thrown straight up. Make a statement dspo3 g eh(cb-w5 *ju8about the velocity and the acceleration wheno5dp(*u8cej h w3gs- b the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceler+f:6ud(ah+- favic oaation just before it reaches its highest po v+ hua(a :d+cia6off-int?

  Suppose a ball is thrown 5xp7jf, o/spystraight up, reaches a maximum height, then falls to its initial height. Make a statement xp7f s5/j,yo pabout the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum hu )u d xp6m3bm+mpgog,:hwj(t90gry w8a. kw0eight, then falls to its initial height. Make a statement about the direction of the velom)80p+hgup a .9b,moj kmy : tw3wgg xu(rd0w6city and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absenchc(3 ful)djpd;6o x0 nf4+lu2 dqpj)h e of air resistance. Make a statement concerning its accele(j)j2;) 0h+cdhx43l lupffqdund p6 oration.

  Suppose a skydiver jumpswxloiow-*8 5 s from a high-flying plane. What is her acceleration when s -l5*xwsow8o ihe she reaches terminal velocity?

  A ball is thrown vertically upward with a spee o4 cx+kuv*o9sd 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 second ball to that of the first ball? (How many times higher does the second ball go thau*xv 9 4ok+cson the first ball?)

  Ball A is dropped from the top of a building. One second lg -f5+bxp gs5bater, ball B is dropped from the same build5f bggs5b p-x+ing. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One second9z.j.5bf9 haw0 zmf un later, ball B is dropped from the same building. As time pru w95mzf.b 9az j.0hfnogresses, the difference in their speeds

  Two objects are thrown from the top of a t skc5p0qs 2mx 2ubs5c .ptqtz ift,2p.5qc(k-all building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds whc0p xz(c -.q.i q2ssbk25ttq5p mu ,52fkstcpen they hit the street?

  A brick is dropped from the top of a building. A second brick +w)zk)e-t ehq k7x bw1lj7iu8 is thrown straight down from the same buildingz eku))7bw7 te-ljwk i+q8x1h. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. The positi3u; e wnv0himmwj. 5:lon versus time g.0meu3wjvw ih:m;5 lnraph of this object is

  An object is moving with constant non-zero acceleration in the +x /gh(ckj0ttp;-y +hr g axis. The position versus time graph of this object ishg(rjktpc0-+hg/ y t;

  An object is moving with constant non-zero velocity in the + t9tvzp/rxwwc4o1qdy: (s81 gx axis. The velocity versus time graph of this p dwt(:o1zqsv 4rtwx891gy/ cobject is

  An object is moving with constant non-zero acceleration in the +x5 v+i tu(aakn( axis. The velocity versus tianvai(t+5u( kme graph of this object is

  The slope of a position versus time grapea vm)6d 38zrth gives

  The slope of a velocity versus time graph givez/ndckq *v5 *bs

  The area under a curve in an acceleration veu 2br85tlw4is rsus time graph gives

  The area under a curve in a velocity versus tim- qts.)ry ce88 mdkzy6e graph gives

  If the position versus time gra4yj azq7hvgu/4*x( xnph of an object is a horizontal line, the object xh74 4n qgxazu/(v*yj is

  If the position versus time graph of an object is a vertical line, the z rg46b-ewu)ja ozmlw5x1 2p6object isgw-e)m 5jou r6b62zaw zx 4pl1

  If the velocity versus time grap; 9ztf )c :bupkt): k8yry/ftth of an object is a horizontal line, the object fb8 :c/ ytytuk;p9))f:rt tzkis

  If the velocity versu4ym cn6a)aled( -y-jxvdq ,9k s time graph of an object is a straight line making an angle of 30 degrees with the time axiq9(jy,d6eca-m- lky4a ndxv) s, the object is

  An object moves 15.0 m north and then 11*e1 5k h au)pyef 3.92ypuzbcf.0 m south. Find both the distance traveled and the magnitude of k)ue 1pfac ypuf3ey9 .*h52bzthe displacement vector.

  A boat can move at 30 km/w6gzalg .w3kd4 *w3tth in still water. How long will it take to move 12 km upstream in a river fl.4zwlgt*w6 tkg 3 ad3wowing 6.0 km/h?

  55 mi/h is how many m/66 aekw8f y2dk wv26xnox.sg r9o, z2is? (1 mi = 1609 m)

  What must be your averageq bhqg 5(s1rs+ speed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 4i jb/5bukt+0 j2.0 km) in 2 hours and 57 min. What is the average speed of the runner i bbkji/05j+tun m/s?

  A car travels 90 km/h. How long does it take fojkh) f.s x4p8yd2 xpf, r*fww6r it to travel 400 km?

  A ly (light year) is the distance that light travels in one yh1)el7muto4 a lvl-doj;x z*.ear. The speed of h4ldza)x em 7*tv1 o-ul; ol.jlight 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 fa:64l,3*zv3rf (ex uja( c:epu zvwmdor 4.0 s, how far do you travel duringv3 am u: 4vfd 6x3upc:ez(e(wzal*,jr this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, y+y /1m bw*rgnjour average vel1m/wgyr* n+bjocity is

  A polar bear starts at the North Poy/ 2mipx.c/ vsp 5uclq/4zqw6 le. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, thenyis4 qx p2/l/qc5.cmvwu6 /zp 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 1.0 km south, then 1.0 kmc61)s;jsaowzy3u 2bnz b3oq4 east, 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 velocisbnqz1y 4o3 zsw 2ua;o)6bjc3ty?

  You are driving home on al9hl2m-w16l jbf hu*1lslws2t :,x ba weekend from school at 55 mi/h for 110 miles. It then starts to s1w l2lll12hs ht l*:j-xbs,a9um6w bfnow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h.wny0 0/ yav b4ugd3+wx What is the average speed of tw/yywb4gd0 vu3a +x0n he motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/hjx3u xigh)+ ed+q7.x r. What is her average u+xqj)e7 +idgxxr. 3 hspeed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north f8 gv4x8m5n1d zbah hgup9(80u eb:icuor 750 miles. What is b8mhua8uhez gc15bn4vi0 9(ud8 : xpg the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for q q)sg)v2c,ghw+yn)q3 oc7pateam 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 l h7w)vnq)c sgy3g q+o2a ,cp)qose the race?

  A car decelerates uniformly and comes to a stop after*u0 ol)3zk0i jsoep2v 14 s. The car's average velocity during deceleration was 78 km/h. What was the car's deceleration while slowing down2eo kj *uio0 s)vl0z3p?

  An airplane increases its speed from 100 m/s to 160 m/s, at the averagejr sdhp0aw*y9f 8b1grv/60 gp rate of wya/r p1p9*rb08vf dg hs6j0 g$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerate z 2rx ig*5b.x4vexf-us 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 acctd6bpx6y h.0f elerates 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 t.x t5ks+m.xm h;c)sk then speeds up with a constant acceleration x.ctkx +) ks 5mht;ms.of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initiali1t( 8(k1lieq, ly o3ct/zepy velocity of 2.4 m/s experiences a constant acceleration ofke3zl(p ,11e yit(y olt/8 iqc $2.1 \; m/s^2$. What is the cart's displacement during the first 5.2 s of its motion?

  A bullet moving horizontally to the right (+xblx14 zatftut(f0* /w direction) with a speed of 572 m/s strtuf0t1f 4t*labx/wz( ikes a sandbag and penetrates a distance of 57.81 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched71 gab86 2b()rx rlif5dgueh y from a catapult on an aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requiradr 86gh b(2bfix)lrg7eu1y5 es 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant acceleration of134g ec*ghh-n aoem n.ch:r v4 $2.0 \; m/s^2$ 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 ap;141et(mymdg gbf5 y distance of 200 m. What is its average acceleratiobyg1ym4et1 f5;g( pd mn?

  An object starts from rest and undergoes unifoj3jzzy r+o+ 9yrm acceleration. During the first second it travels 2.0 m +yz jjroz+39y. How far will it travel during the third second?

  An object is moving in a straight line wity*xakk*a3-0rot+h2 mujt z o9h constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far doeso9u2r* t kxmh3a0jytz -o+a*k it move during this time?

  A car starts from rest and nas;7.a.tt/ eroi+-wfdv y w8 accelerates 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 y:k 3p8lnyucv;ui g70wshs-( can decelerate at about $5.0 \; m/s^2$ when braking. Suppose a car is initially traveling at 55 mi/h.
(a.) How much time does it take the car to stop?    $s$ (only input numerical values)
(b.) What is the stopping distance?    $m$ ((only input numerical values)

  At the instant a traffic light turns green, a car that has been waiting atm(rma 31ysee 8 the intersection starts ahead wityre3(samm8 e 1h a constant 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/n+gqi*(f mv oit2y3t17gtk r-s on the surface of planet X where the acceortgy723(igq n k if*mt+t-v1leration due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12 m/s on the surface of planet0/b wx jlzu2m5 X where the acceleration ul5 zj/x 0bw2mdue 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 surface of psc .-(9n, vp lbg-hafdlanet X where the acceleration due to gravity i- .gb,fda(hc9 spvln- s $2.5 \; m/s^2$. 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 -rur cl3ttyp3. nbcmc2/ lsa:e0 gh)6 the surface of planet X where the acceleration due to tyu6 t bpc3ncl ec r.g0)h2l-:/3amsrgravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually greatero/4w (v-zvp qu(fv m+k than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can youv ku p+-om4vqv/ zw(f( expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of9f6kti6y s(hjx)n: hsd+:o sd 19.6 m/s. What is its velocity after 3.0 dh:st+) x(ho: ski6f9ydj ns60 s?

  A bullet shot straigh mmb52)x+inhu -be*w2 um-mtet up returns to its starting point in 4 s. What is the initi2-u + mmh- )m*nt5xu eb2ebwimal speed of the bullet?

  A ball is thrown straight up with a speed of 3c vetsw))2ekd6 c-q 8n6.0 m/s. How long does it take to return to its starting pw2 nec-dq6)ect)8 s vkoint?

  A ball is thrown downward from the top of a building with an initial speed cwve() 0hw:1 hbwy mi7of 26 m/s. It strikes the ground after 5.2 s. How high is the (0e)y 1hvw:cbw7imwh building?

  A ball is thrown straight up with a speed of 30 m/s.u1asq39nh n 0cc4wg3 pgb ,sc, (only fill in numerical value in tspc c33uaqb0gc9 w ,ngsn1,4hhe blanks)
(a.) How long does it take the ball to reach the maximum height?    $s$
(b.) What is the maximum height reached by the ball?    $m$
(c.) What is its speed after 4.2 s?    $m/s$

  A foul ball is hit straight up into the a er,f3qh,fyn 1ir with a speed of 37.4 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 11 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 11.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t =zozm3( g ;jpbfq 0z+bac w;l-/ 1.0 s?

  In Fig. below, what is the velociw1 -syo z42a) hszbq .o(wtp-9xub *ncty at t = 2.5 s?

  In Fig. below, what is the vel0nzje21os k5pdmuz) pc +u 30gocity at t = 4.0 s?

  In Fig. below, what is the velocity at t = 5.ahdlakil1rqt.x e(8ce 1j:4 n5;e3 jq 3 nrf.d5 s?

  In Fig. below, what is the averagetaoash 0d596- ( ovwbq velocity from 0 to 4.0 s?

  In Fig. below, what is the average6yfi/c )5 bvedzjro *+ velocity from 0 to 6.0 s?

  In Fig. below, what is the accel/)h frn j-okn,t n3s8feration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 s 6 wni63pimh; 4mmvpj92a-youx+7 hvu?

  In Fig. below, what is the average7 y4f 76zj3zp0xyq oxq acceleration from 0 to 5.0 s?

  In Fig. below, what is the 3ra0t m/d-bvd- fv3 v.o-p,c.jm rgv)xdc. nwaverage acceleration from 0 to 8.0 s?

  In Fig. below, what is l j7rggf*+tuleo8gj a- f(7( pthe displacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocitjf 4qk:27afj jy? {speed|velocity}

  An object can have a v;.w1vh7+fnwo8 +sx1dch vu sparying speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is vv o.o.k sw8s 75wv)k:fuw1 blpositive.

  If one object has a greater speed th6qnvav -r /ryvcq- 0g3x1udt/an a second object, the first must have a greater accelerationgcqq0-tvx / r3 darv-v/y61u n.

  Two cars emerge side by side from a tunnel. Car A is traveling with a speed of n;xf dsk*tu. 0$60 \; km/h$ 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 itsuw+r5f9tx (c, fwt/nk acceleration decreases.

  A baseball player hits a foul ball straight up into the hs5/gjqp y1yqmxp22y 9 x 2gq(ue o:c6air. It leaves the bat with a spgxp6h( o2u 5 pxgmq2yqje1 2ysy:/q9ceed 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 ac7zg5 a;;z hoyg1ut/ e0q5fj rfceleration, how dof1y/qzg;0r57ej tf hz5 oa;gues it change if air friction is ignored?

  As a freely falling object speeds up, what ipf-z-t,t+t ys s happening to its acceleration, how does itz ytpt, ft-s-+ change if air friction CAN NOT be ignored?

  An object that is thrown vertically upward willz 2p*a-t,rqk ,tdky v. return to its original position with the same speed as *z,yqak dtv,tk-p2r .it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity an-kt xx,no7b5uaf uqqy,8 j j-8d nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at the same find vxwyyl3v*raq ) gs:;m-*ri ;y 66time.

  An elevator moving from the second floor tf ru11,2fq deb3(w 5jjgr2sh;nj zok0o the fifth floor making no stops alonz 2 jf3dkbgq2jsf er,oh;11j 0n w5(urg the way has zero acceleration all the time.

  A rolling ball moves f4hvx/ei3/xaa 0zoqi 0 rom $x_1=2.3 \mathrm{~cm}$ to $x_2=-7.8 \mathrm{~cm}$ during the time from $t_1=2.9 \mathrm{~s}$ to $t_2=5.3 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.4 \mathrm{~s}$ is at $x_1=3.3 \mathrm{~cm}$ and at $t_2=3.5 \mathrm{~s}$ is at $x_2=8.4 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete la95pecd8hft8i ,2bdlv9* b dpaps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.9 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,8 sdwvmzk-jqh,yg. rj2l6sf+q ++uy5 moving 114 m away in 8.8 s. It then turns abruptly and gallops halfway back in 4.8 s. .++qs8rs,vu6w-m5kgjhlf2 zy yj +qdCalculate (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 froa /vao9urk hu(wzvaz7f 69 z,)m $12 \; m/s$ to $24 \; m/s$ in 5.2 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 fro9czp)lfsqvh / y-9;zjm $17 \; m/s$ to rest in a distance of 62 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed hw+a +c1xl m+,onpz:vof $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.2 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially to (5 xbb6dyelbb563eb tp speed about l(5bb3d by56 b xbeet6$10.0 \; m/s$ in the first 13.6 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 unif gjp,2)w yh w,totvjkq n;w0*9ormly from a speed of $18 \; m/s$ to rest in 5.52 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid j+dmyb( +-.vw*kdo tj;w6nromarks 92 m long on the highway. Assuming a deceleration ovokodj;*++b.(wrwy j 6 tmd n-f $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goio2s5n aoe,ha z-7*nr jng $25 \; m/s$ 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 complb5 -h fhr2sn:s2sop :rete the 10,000-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 mh2p sssr:rnh 5b-o2f: to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$