Suppose that an object travels from one point bty3 8ll( -fopin space to another. Make a comparison betf8llt3 (-ybpoween the displacement and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velocity?zw-/j+gn3ih 2u fwic7

  A new car manufacturer advertises that their car k; q vysmk;+i*:(i nqlcan go "from zero to sixty in 8 s" qisk+ qv*;:yl; ink(m. This is a description of

  An object moving in the +x axis expyy z ;aks+v:9reriences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+jf :vjcc-nf *a. edo+0x direction) begins to slow down as it approaches a traffic light. Make a statement conca cf .+d:ve*cjnj-0oferning its acceleration.

  Suppose that a car traveling to the West (-x d(up fc1 1u5nuxirection) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleratiouu5 (1 pcfun1xn.

  Suppose that an object is moving with a constant velocity. Make a s4da-uqn)ubn)cy jaq-6c 75 bitatement conce jyu qcq aa)i)7u--4n6 5cndbbrning its acceleration.

  If the velocity of an object is zero, does it mean /+p mfo rqg6.zg;q6.g;dnt6rzv4 yad that the acceleration is zero? Support your answer with a6v;tf 4+grdyr pmaqnd 6;.z/go.g6q zn example.

  Can an object's velocity cha,d9t v:-nmfti89 mjbvy2 k+w x)vgkn/(j jne6nge direction when its acceleration is constant? Support your 9ijj8f+nm9,( n)6bxv:yvdk wtnvekj- 2m /gtanswer with an example.

  Suppose that an object is moving with constant acceleration. Mawqj,edsl ( czjo(mq,o/3w 04+d rkyk;ke a statement concerning its motion with respect to 4wje+ d/,3qro ys(,mlk;zkd(cqw o0jtime.

  Can an object have increasing sdm2fwuh.s0 ye6(56khf5yy.,keem -l y wc1fspeed while its acceleration is decreasing? Support your answw le.ce5s.my61 ,yfh 2dm0fs(wf6-yk euy h5ker with an example.

  Suppose a can, after an initial kick, moves up al 5svqapho ;s8r,7+p qfong a smooth hill of ice. Make a state , sr;a7p vo5qs8p+hqfment concerning its acceleration.

  Under what condition is average velocity equal to the averagemug9q g.3mv); ;ai 3yzxx;kyw of the object's initial and finaavkyzm93;ygi 3; w )q;.mxxug l velocity?

  Objects A and B both start at rest. They both accelerate at the same rjs1z1sj -0 ;bnl v4pssate. However, object A accelerates for twice the time asps1s - 0jbljs1v4 nz;s 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 both accelera bhak 8lkha9 al*gm2 aq:n:ds 6uo*v5:te at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared to k:ovubk a* a:8d:gl*s9hqn5ma 6a 2l hthat of object B?

  When an object is released from rest and falls in the absence of fr+z z jt2bm hpw+7oc22ykehlf)/u;4syiction, which of the followink+;t2u/e mls4zh p7y 2 bh2)o+zyfjc wg is true concerning its motion?

  When an object is released from reo)i 9+p -xyr 8) jrqoudzbck+.st and falls in the absence of friction, which ofpi)rq cx98dr obz).u k -+yoj+ the following is true concerning its motion?

  Suppose a ball is thrown straigh : wq:d mjhnisi6l53oyem:4/mt up. Make a statement about the velocity and the acceleration when the ball reaches the highest point.sjmm:d:e:435 i 6wnmlh q oyi/

  Suppose a ball is thrown straight up. What is its ac xd;x;uxc-e7zd my 6;)od z(rcceleration just before it rxmoxu;d ce-;drz)dy( xc6 7 ;zeaches its highest point?

  Suppose a ball is thrown straight up, reaches a maximum heigv,zx1kxp/ 5r c7yoq3i ht, then falls to its initial height. Make a statement about the direction of the velocity an,z1qxick5y 3vx op7/rd acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then faf 10nb4)engyy lls to its initial height. Make a statement about the direction of the velocity and acceleration 0f1n4 ng)bey yas the ball is coming down.

  Suppose a ball is thrown 4hg4yip z 3,8g gzhhk5*jf mn7downward in the absence of air resistance. Make a statement co,4zyi m 3zghh4g* 5kh npfgj87ncerning its acceleration.

  Suppose a skydiver jumps from a hig.rep1434rp s34ciejql w q1m;syah5vta4e 3 lh-flying plane. What is her acceleration when she she ry wc315tar 4vlh 1rsem e .elipqq4j 3s4p4a3;eaches terminal velocity?

  A ball is thrown vertically upward with a speed v. (3;isl,n on,zb ahmcg; ;wwns ;gk2(o An identical second ball is thrown upward witi (nz;2w og(kb l cmn,w;;os3 ngh,;ash 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 the top of a building. On4suvmz,tg qk72z./ g se second later, ball B is dropped from the same building. As t gtukzsm7s.z4v, q2/gime progresses, the distance between them

  Ball A is dropped from the to tgjq8a )30msh-av2wu p of a building. One second later, ball B is dropped from the same building. As time progresses, the difference in thev q ja8m320- agw)tsuhir speeds

  Two objects are thrown cy; sd r9y4tg3 iq3:pyfrom the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit;t 9r:s3pcyg34yiyqd the street?

  A brick is dropped from tp7/iozel -nm.he top of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air zl-o/pi7. e nmresistance. Compare the accelerations of the two bricks.

  An object is moving with constk-sx6i pt:yx, kbr r-jlz8en f:*ph(*ant non-zero velocity in the +x axis. The positionkkpi6 r,*-:xt yfe8-bph*nlx ( z:sjr versus time graph of this object is

  An object is moving with constant non-zero acceleration in the +x axe ys zis44ru9)is. The position versus time gi r)4ssz4y9euraph of this object is

  An object is moving with constant non-zero velocity in2 pq3 8h4q kfktt.zf9kf s8. */fiacitrw53pf the +x axis. The velocity versus tim aik pf w.r8fz*q.k4t f/t3iqh92 kpsftc853fe graph of this object is

  An object is moving with constant non-zerokt8 gjopg/: ejvp/+ (tl s7d3q acceleration in the +x axis. The velocity versus 7gs3 ljjtgq pk/v(t:dp8 oe+/time graph of this object is

  The slope of a position versus time grapq3tq y a u.6:/ldlq5eoax ;tg3h gives

  The slope of a velocity versus time uui7 6fge0/cu;v fv68ohdm*zgraph gives

  The area under a curve in an acceleration vw4:v)9 hie w,jxa:g vyft4a s6ersus time graph gives

  The area under a curve in a veloc a6 2 (+r9zd rcd*hepezx4n3waity versus time graph gives

  If the position versus time graph of an object is a horizonta 3e.eso;nth *gl line, the object isgn ;ee3to*s.h

  If the position versus time graph of an object is a vertica vssigpl/r e(o8bb5t o gdw4485)pw,nl line, the object isn5pgpd/o4si8 b 8v,tolbr4g) w(es5w

  If the velocity versus time graph of an objec xa37 w0wufdxqm5, ;zvt is a horizontal line, the object iawzv;xf 50w 7dmqx3,u s

  If the velocity versus time graph ojd0neo0 64s4 brpf* rcf an object is a straight line making an angle of 30 degrees with the time er4 0sb0f 6p*or4jdncaxis, the object is

  An object moves 15.0 m north and then 11.0 m south. Fi qfzbux,d.f3z1v+wu )p 2zigkr+7 ce6nd both the distance traveledc+u,.d 2 1zfz7wpbi+3k qzxf rve6)ug and the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long mp)bdgxl-v- ytzv/t) djg 5 15will it take to move 12 km upstyd5d b)tx -g-/pm51)gv vtjzl ream in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 6mutf mg(0+ mm5:qhguu7 uzef;-wh kmt9le/(1609 m)

  What must be your average speed in order to travel 350 o mpo6i)lpz7-+ enpl-0dr7 ge km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. m(n i0l h2p 3f58biangWhat is the average speed ofl 8p0mnh abgnf i25(i3 the runner in m/s?

  A car travels 90 km/h. How long does it take ,k,oc *(wclhjm6, kqffor it to travel 400 km?

  A ly (light year) is the distance th9ce)kko94ar rx 2 qx8tat light travels in one year. The speed of light r2 a q9o x89kt)cxkr4eis $3.00 \times 10^8 \; m/s$. 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 for m0sv2 :c, ao r)r8e0kufh wq0ihtw -3m4.0 s, how far do you travel dura kvt:uh0qm-80eiwh)wm2r3 cs o,f 0ring this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, your a49/t) t y2dxics .hbyf(ayzu)verage velocsyuc)2x9)dh( i z/ y4 ytf.tabity is

  A polar bear starts at the North Pole. It travels 1.0 km south, the7 fk*ffjfpeyx 5*s3ufdubq ; 7u+:) vjn 1.0 km east, then 1.0 km north, then 1.0 km7e pff *5f*bu3f7+jvf)q xsu;:uy dkj west to return to its starting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts atzxzm4e r*08 ou the North 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. What was0zzxeo * 84urm the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles. It then41 t 0,xig7fir+u izn.vlx9 as starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometown from schoo7. +x4l irizn fgx iv,9tasu10l?

  A motorist travels 160 km at 80 km/h and 160 km at 100o g 76gh a-q-oqx2.kdc km/h. What is the average speed of the motorist forgq.o-gd2a-7 6cx oqkh this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. k9n3zfw(nbk2eonh t5 +s:td2 What is her average speed for thehen2btf3 zn:dknswo2k 9+ t(5 trip?

  An airplane travels at 300 mi/h s )lr:oqctlyt- tmrf gk. 49v*0outh for 2.00 h and then at 250 mi/h north for 750 milt9 rmt). kf4lv:l0ry*-cqg otes. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who ru.aiciu.v0 is k n+79vrns 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 10.1 s. What is the largest lead the team B runner can have when the team A runner starts the final leg of the racevic .ui9nvr0a.k7is +, in order that the team A runner not lose the race?

  A car decelerates uniformly and sj-6ft uwe1+med v,p0comes to a stop after 10 s. The car's average velocity during deceleration was 33 km/h. What was t1 dvp0,+mewste f j6u-he car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the avcjt,*6n gs +mverage rate of n,mt v *+s6jgc$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h j,l -m-i8p*wr ed-f8f fs -u9ptz m-aiaccelerates 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 accelerates at bcxj2 fs*qkn/ 9gz3j4$4.0 \; m/s^2$ 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. Itirg5 seyt,-u7 3etca r 9)fy2 lb;2ztm then speeds up with a constant acceleratiomt2-ut ry53lbcest );gif9a,2z y7e rn 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 3.6 m/s experiences aek yt9gw1j.x 5 constant acceleration ow gy5tke x9.1jf $3.8 \; m/s^2$. What is the cart's displacement during the first 8.0 s of its motion?

  A bullet moving horizontally to the right8 ni-q1 :5tnb rsy2 hoo:c aj8tfyiy(( (+x direction) with a speed of 374 m/s strikes a sandbag and penetrates a distance of 67.20 cm. What i:( sb cjtyny-(n8oar 1yhqi2 : 8io5tfs the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carr)f.zkof th;m *ier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the accelerationtk;z.f mo* h)f is constant, what is the length of the catapult?

  A car starting from rest moves with constan*.e 3cz*zs2vf.kh 0dp qhda0h,kt f,bt 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/) f+/wp vu+rs5f)qp we8ewa :elr8r0bs in a distance of 200 m. What is its average accelerati)e+ff+eslq)w0p wvr /rw8br a e85:upon?

  An object starts fro);m rt g:qjp3ket 5dj 5j(rfd6m rest and undergoes uniform acceleration. During the first second it travels 10.0 m. How far will it travel duringjj pkmt3)j(q65dgdtr f5 er:; the third second?

  An object is moving in a straight line w *6ignzm5d tx- pc9r;2bhr4h l0p/lf cith constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. i*l;c 6ghx9 b p5 rrf/clmnd0p2-4thz How far does it move during this time?

  A car starts from rest and a1q5l *nwji6p1vqg7w :k5g pg b:r-csaccelerates 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 qdkmfgo:la3n fg0puy* 9 ,4g6decelerate 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 ha.i7s(i wxikl7v74v-/uegszjs been waiting at the intersection starts ahead with a constant acce7s 4(siwz7ikv-/ .x iujv7gelleration 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 w a 0 q/w7s-4hhkypmx+rith a speed of 12 m/s on the surface of planet X where thraskx47 /hy-pqw+ 0h me acceleration 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 plan4vucf1we j br86qsl9kpi 29c. et X where the acceleration due to gravity 8flsrbi2 qcpjk.9 9 v ewu16c4is $1.5 \; m/s^2$. 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 plaer j4mn,- ;7ec eewa-iq ;7uwcnet X where the acceler,77-mcre ie ; eu-c q4wjnw;eaation 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 fluj8hi . i(aswep6kv;/vyk; )2vfr: the surface of planet X where the accelera kf;(;av y wuvrf8k2/isv :iej.h6p )ltion 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. If your frienmx;jifd, vyz+ 4 hli:0d holds a ruler betwexv ;ihj+yz, il 0m4d:fen your fingers and releases it without warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upwar4hv7*z: hjxc/donv-c d at a velocity of 19.6 m/s. What is its velocity after 3.vjdhxhov n:*c/7cz- 400 s?

  A bullet shot straight up returns to its iaod)fiw :3ii/67zrlstarting point in 7 s. What is the initial speed of the bul/:zowifir di a i3l76)let?

  A ball is thrown straight up with a spee0klbstgx-tl.q 8 s*j0d of 36.0 m/s. How long does it take to return to its st.tss*gk xb0t8 qjl0l-arting point?

  A ball is thrown downward from the toj-g6 /vqpjo1 wp of a building with an initial speed of 10 m/s. It strikes the ground after 4.4 s. How high is- gw6ojj qv1p/ the building?

  A ball is thrown straigh,5j5dnl t 4j;;vpjjr vt up with a speed of 30 m/s. (only fill in numerical value in l ;jvv4npr5,j ;tdj5j the 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 /:7vaeehd,d fqx e-6iinto the air with a speed of 36.8 m/s. (use $g=10 \; m/s^2$, only fill in numerical value in the blank)
(a.) Calculate the time required for the ball to rise to its maximum height.  (数值)  $s$
(b.) Calculate the time for the ball to fall back to the height at which it was hit.  (数值)  $s$
(c.) Calculate the maximum height reached by the ball.  (数值)  $m$
(d.) Calculate the ball's speed 1 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 10 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 10.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is t5 ou)9kqdvz y-:3uuatyp 3/k bhe velocity at t = 1.0 s?

  In Fig. below, what is the velocityy-t2g dc-m(kfd.h(k a at t = 2.5 s?

  In Fig. below, what is the u7 mqt xfhs*k a0(pti*k14 *ynvelocity at t = 4.0 s?

  In Fig. below, what is the velocitnjg4d xf uv4+af240. v d8bpndy at t = 5.5 s?

  In Fig. below, what ian1 pl fpteg2chzqi6b6r/)s:mr+g )3s the average velocity from 0 to 4.0 s?

  In Fig. below, what is the,2 nebneddpa vhi 82)0 sgd44w average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration cq .rtq3tq9n pm/+8 ilat 1.0 s?

  In Fig. below, what ijhgl)ohk.c, b -;3 fqis the acceleration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 to w ipi5oq 9ol765.0 s?

  In Fig. below, what is the average acceleratio 1 8:kbk.cxpa/a n3eqiqy9h-vn from 0 to 8.0 s?

  In Fig. below, what is ths:g s4on/s; mvjc6s s5e displacement from 0 to 8.0 s?

Does a car speedometer mea-r oli x kk 04- e02+v69nirsuhvwy iion.il-1sure speed, velocity? {speed|velocity}

  An object can have a varying speed if its velocity s.z0qy/x a qf:is constant.

  The velocity of an object can be f/ucwkomni: f;:lb m.w)c2 1c negative when its acceleration is positive.

  If one object has a greater speed than l8 4cqy( ovwk-3ec j3ta second object, the first must have a greayl 8ckc4 (3t e3wovjq-ter acceleration.

  Two cars emerge side by side from a th:+h pbzlk /c2 x+vuon u51i:uunnel. 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 acceleration decreasei is;(f kw-fh0s.

  A baseball player hits a foul ball straight up into the air. It leaves tm +-z9di zj-b08jkfo)8rredn a+obbg:02y hwhe bat with a spee z kr mn-9bd0f bjz )-+ao2yibw0hro+ge :d8j8d 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 +h q6kyh;k n3jobject speeds up, what is happening to its acceleration, how does it chan3y +;qhk6jkh nge if air friction is ignored?

  As a freely falling object speeds up, whatwwmdg sl773 382wvxfr is happening to its acceleration, how does it change if air friction CAN NOT bewwx2w77r 8mf3d3 slgv ignored?

  An object that is thrown vertically upwabjx 2n8cv2u3h*qepb q c-2e r1rd will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appre2*bpe hb3qx rq8 u2j-nve1c2cciable, how will this result be altered?

  An object can have zero verq3sf s58srx2u2u /ij locity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at the same timezzbgfc,p(qw 3 i.e8q).

  An elevator moving from the second floor to the fifth floor mayc u,2.6co71ygla+bgey h ;cyking no stops along the +6cyh.y;elgoy 27bg ,c acy u1way has zero acceleration all the time.

  A rolling ball moves frow2u9d2vsvh9x z t0upd 9kox65 m $x_1=1.6 \mathrm{~cm}$ to $x_2=-5.2 \mathrm{~cm}$ during the time from $t_1=1.9 \mathrm{~s}$ to $t_2=6.0 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.4 \mathrm{~s}$ is at $x_1=3.2 \mathrm{~cm}$ and at $t_2=3.5 \mathrm{~s}$ is at $x_2=8.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete ab.6/ bfdqg vlln-(oa++mba0 ep l:1klaps around a quarter-mile ($1 \; mile = 1609 \; m$) 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 stra4,9esl)xoisn*nmy : g ight line, moving 88 m away in 13.2 s. It then turns abruptly and gallopsosi* n)n9 xg,: y4slem halfway back in 4.6 s. Calculate (a) its average speed  (数值)  $m/s$ and (b) its average velocity  (数值)  $m/s$ for the entire trip, using “away from the trainer” as the positive direction.

  A car accelerates froyuuu6i cz gq7 vn11cr (6e89sam $13 \; m/s$ to $22 \; m/s$ in 4.7 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 i t psw232ca yb-w8v1x8 ycb+q$22 \; m/s$ to rest in a distance of 65 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a sm 5+o3nv/pby -bhc lh+peed of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.6 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially topb4;id+;em yql speed about deq;4+b m;ly i$10.6 \; m/s$ in the first 10.0 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 z.qdtn*i2o 2y from a speed of $20 \; m/s$ to rest in 4.40 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 hzc;-x zo sj g4lgcb5 7b4y*fv3ighway. Assuming a bzv5j37z4g4cfx - lygs;cb* odeceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goi8 09j wwhgzcb:ng $25 \; m/s$ 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).    $m$