Suppose that an object tr .0hhc )g:roxmavels from one point in space to another. Make a comparison between them0xh )c.r: hog displacement and the distance traveled.

  When is the average veloc0.ytz+ln du6tlrxk1 2ity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "from zero to )ks/je4t ,d bslh3 :ghfrh-9xnh; g (rsixty in 8 s". This is a dgjbk9sheshx; h ,l :t )fh3rn/r-4dg(escription of

  An object moving in the +x a,x qnvu/ u/zl9xis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow u a0d. pdulm),down as it approaches a traffic light. du, d. 0alu)pm Make a statement concerning its acceleration.

  Suppose that a car travelin*vd(7gow ; o,jvt:lp cd) ;j0bmj c/zrg to the West (-x direction) begins to slow down as it approaches a traffic light. Mak ;w(ldz b/opcvj;*djov t),cm7:g0 rje a statement concerning its acceleration.

  Suppose that an object is mx8lp-v7c rpu *offa7anb(6s/) t m,ocoving with a constant velocity. Make a statement concerning its acceleration.fu v roco8bp,7n 6slm-aft/* (axc7p)

  If the velocity of an object is zero, does it mean that the acceleration is ze: ).y:r )6tgc ofguzrfj(eg. rro? Support your answer with an exampgutfgf)ror6 ze:.cj(yrg) .: le.

  Can an object's velocity change direction when its acceleration is covx p681lqzkbz/i5 int 5/2vn anstant? Supp/ i6bk i2nq l5vzzax1 v8/n5ptort your answer with an example.

  Suppose that an object is /w,mg ;t+h4zwk9 dflgmoving with constant acceleration. Make a statement concerning its motion with respect to g+k 9f4wl/, gmdht ;wztime.

  Can an object have increasing speed wh:.kev3 jzr3 huile its acceleration is decreasing? Suppo3zrv uk.:eh3 jrt your answer with an example.

  Suppose a can, after an initial kick, moves up along a smooth sm- c )vpz*1kghill of ice. Make cp-mvk g*1)sz a statement concerning its acceleration.

  Under what condition is average vev ia,;t.tcpj+locity equal to the average of the object's initial and final vela,;i.tp c+j tvocity?

  Objects A and B both start at rest. They both accelerate at the sam*2xk26ov; yih a.jh dpkjd.4j e rate. Howev..j2 hj6odpy k4vhxkd*i;2ajer, object A accelerates for twice the 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 both acceleratet,-ef r *xtvr;-xm/(h)qsc iz at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by obje f xev(tmr-*,;qxc/ - hsz)ritct A compared to that of object B?

  When an object is released from rest andm;2b +a r7 tx4zjm,wvg falls in the absence of friction, which of the following is true concernia4rvx 2;z+wbtmjm g ,7ng its motion?

  When an object is released frompg/erv5qv ;;q rest and falls in the absence of friction, which of the follv5gq rq;pve/ ;owing is true concerning its motion?

  Suppose a ball is thrown straight up. Make a statementx.ntb(gyk0;f4++ w z +vv4ewht( dze z about the velocity and the acceleration when the zv4y+ ;t eh t+kgbw+(n z4z.fxve dw0(ball reaches the highest point.

  Suppose a ball is thrown strat.,r85hvno ciight up. What is its acceleration just before it reaches its hig8rc5vo ht.,in hest point?

  Suppose a ball is thrown straight up, reaches a maximumzfal4,l.uvy7h xqis z-e-3s* height, then falls to its initial height. Make a stateml-.lhe 3q uf4sx* ivaz7 y-,szent about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to its initi, qeolj5kjb-;w4n3 ow *y2udual height. Makeudjln*-w ouj3;,w 5b4keyo 2q a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence ofew .hjir e:n*)u,g;xa air resistance. Make a statementhi gw:* ra,n .e;jexu) concerning its acceleration.

  Suppose a skydiver jumps from a high-flying u-dzumf de:;hdx-n -1 j da4w7plane. What is her acceleration when she she reaches terminal velojd:dzfdumu-nw 4-dh xe a;7-1 city?

  A ball is thrown vertically upward with a speed v. An identical .ap*e)t d *y/:dblizisecond ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum h* d/:izl.beypi*) a dteight 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 t:i g.b c9- f,og(ytyupdw y15dhe top of a building. One second later, ball B is dropped from the same building. As time progressfcp:5ybit91dwo du- ggyy.(, es, the distance between them

  Ball A is dropped from the top of a building. One sejqqx/ q-t9dbk3w ,zqx7g(1sijr ..j mcond later, ball B is dropped from the same building. Aq,(qgbwkjmzqdr 9/7x- 3j.. qixt1j ss time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall buildhnt 0*p5bi qk09dq3ji ing. One is thrown up, and the other is thrown njb9 pkqhqi5i0dt3* 0 down, both with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown s,p/8( 2mr*m wxz:mtz eerunj;z vw3x7traight down from the same building8t7wz,pjze* mmu x3r zre(mn:/xv; w2. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving opm/9s1 r0xdc with constant non-zero velocity in the +x axis. The position versus p9/dos xc10 mrtime graph of this object is

  An object is moving with constant non-zero acceleration in tb/y ;z7segad/unv wq f ijn(/i(6g)6lhe +x axis. The position versus time graph of this qjwv(a/g/7(n)ie sly ig/ 6b;dzf6un object is

  An object is moving with constant non-zero velocity in the +ys twf0y,k0mi 2) dpp4x axis. The velocity ve tsk4 0mfy0iy2p),dp wrsus time graph of this object is

  An object is moving with constant non-zero acceleration in the +x axis. The vr 13bnq 2n4s+ keqts)jelocity versus time graph ofrq1stq+k2 sbj3en )4 n this object is

  The slope of a position versus time n ew08g6qmm 6q.)gbjlrsr+8s graph gives

  The slope of a velocid1j - 5w)ip6fobbf;ky ty versus time graph gives

  The area under a curve in an acceleration j148 y ,4kssq7m uvifzversus time graph gives

  The area under a curve in a velocity versus time gra:o vr6p: .qvfdxv) qf6v9ht9xph gives

  If the position versus time graph of an object is a ho* vlc4a b,9gz.xqlhj (rizontal line, the object 9g,cbvl(j.*al z xh 4qis

  If the position versus time graph of an object is a verti9;w- mkej)use pc2 0iocal line, the object is2-ec oem)9k wju0ips;

  If the velocity versus time graph of an objectp k5xv:fj1,y7j5znsd is a horizontal line, the object 5 j,ky57 :f xpnjsv1dzis

  If the velocity versus time graph of an object is a st6fmga8py i6a4raight line making an angle of p m8 aai46gy6f30 degrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both tir 66n0,7 ic*x2zl xv2nj4sog kyhs c.he distance traveled and the magnchgs2x06n z4 cni i.v2 s*o6jkxrl,y7itude of the displacement vector.

  A boat can move at 30 km/h in still water. How long wilac-a+rx8+s. pp)lch,vab j.f (zq* f il it take to move 12 km upstream in a rivchp, 8lvf+pa)(ra. qf*-+bcx.s zaijer flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609w7g*k*bdc 0 imikf:+qkjd6j9 m)

  What must be your average speed in order to thc*siu 5( ggs3y4 j;hxravel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 minkjiyo/;krw; o 5 an5:n. What is the average speed of the runner in m/5i5:or;knwkaoj/y ; n s?

  A car travels 90 km/h. How long does it take fo 22dfk)pb6 1f/mokm2tf dv tcy.k)4ydr it to travel 400 km?

  A ly (light year) is the distance that light travels in one year.wvxjz(:7 r( pd The speed of r w(zv(:px jd7light 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 si syc)xd5 q-54 ms p9d18eihszude for 4.0 ssy pzdxim9) e8- sq c4hd5s15u, how far do you travel during this inattentive period?

  If you run a complete loop around an outdoor3svpuf4*ad2dr1-a y l 0hjuj* track (400 m), in 100 s, your average vel4 vau1lf*hsrup2a j30y*dd- j ocity is

  A polar bear starts at the North Pole. It travels 1.0 km sk. cnn4,/ldh vv(caxchq8 t *(outh, then 1.0 km east, then 1.0 km north, then 1.0 km wesktlvq hh. c(x(*4 /,cvca8nn dt to return to its starting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the Northvk (b9 d2ws29bn9uv rd3pf2om Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to retunb(29w kf2s939odvb2d v umr prn to its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on 1ys(s zpwfn ;,a weekend from school at 55 mi/h for 110 miles. It then stfw1 (ns ;pzs,yarts 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 school?

  A motorist travels 160 km at sga : ia5b;ie080 km/h and 160 km at 100 km/h. What is the average speed of the moea;a0i:gs5i btorist for this trip?

  A motorist travels for 3.0 h at 80 km/hq8/h qat 7z3 .ac+kle11 zkqmjz9zq)lnhl v 7* and 2.0 h at 100 km/h. What is her average speed fo qqt zka7hkl)qlcnjz qh18z9v/* z1e7m+l3a.r the trip?

  An airplane travels at 300 mi/ a fts6w f5)8xw6jt8fwh south for 2.00 h and then at 250 mi/h north for 750 miles. Wwjwa f fx6856t)st w8fhat is the average speed for the trip?

  In a 400-m relay race the anc6h5xl93lvp w chorman (the person who 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 10.1 s. What is the largest lead the team B runner can have when the team A runner starts the final leg o llx6v9w ph35cf the race, in order that the team A runner not lose the race?

  A car decelerates uniformly and comes to a stop kw+gc8y3ovpo rs) )x6j al(y)after 11 s. The car's average velocity during deceleration was 42 km/h. )wro)sxa8jp3k+vy()gol6c y What was the car's deceleration while slowing down?

  An airplane increases its speed from 100xc0 xs4g52c9b u sd8zon 0k+*u;xdusb m/s to 160 m/s, at the average rate of u0;u*u bb + x8x n2ozc4d 9ksd5cxgs0s$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acj)s;j3 )k:lgk6 sv.jehbb h y;celerates 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 aja8 mkc0vds+ 9pyp1r7bzw,1g nd 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 cpry, pqs.z*6xonstant acceleration of pyspqrxz,*6. $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 7.0 m/s experiences a constant accelbs:p9 xcg; yngi2pvs8s/4i k9 eration oig4y9igsv;p: s 9/xkn8c2 bspf $1.6 \; m/s^2$. What is the cart's displacement during the first 9.7 s of its motion?

  A bullet moving hori 0c-2+ij uuczmzontally to the right (+x direction) with a speed of 442 m/s strikes a sandbag and penetrates a distance of 16.95 cm. What is the aver-ci2cm zj0 +uuage acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched frovi-o1,ioa1o ym a catapult on an aircraft carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the ai1 1io yoa-,vocceleration is constant, what is the length of the catapult?

  A car starting from rest moves wi19jvq c k64u:)zkhifbth constant acceleration of $2.0 \; m/s^2$ for 10 s, then travels with constant speed for another 10 s, and then finally slows to a stop with constant acceleration of
-$2.0 \; m/s^2$. How far does it travel?

  A car goes from 40 m/s to 80 m/s in a distance of 200 m. 4g;sdhx07a p k What is its average accelersga 40 hx7dkp;ation?

  An object starts from rest and undergoes uniform acceleration. Duringvz8ax*unu(-0tyhic (way 2k+ the first second it travels 2(yi+zhy 2ac-atu w( x u0n8v*k.6 m. How far will it travel during the third second?

  An object is moving wopnozpg9+26 in a straight line with constant acceleration. Initially it isp w2ooz9+6npg traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rec pttvq;3: dj2s-:r, bpnd9vfst and 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 can decelerate at,e7 ekp(oa9 wuyywcw4ef4: g0 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 t y9 lgw-;ye;8igbp hb*hat has been waiting at the intersection stay;gg;8lp -9 e y*hibbwrts ahead with 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/s on the surfacey aly/gc-dr,1q 0;/uk lt9jmr of planet X where th,t ;-0 d/ rj /qlmyrukg19cylae 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 on8ywf*v*g c w(qgl (o( bhrfu /b 0;;nppchi9k, the surface of planet X where the acceleration due tcgw 0 rnkp/( ih *l; gc,ybqup;(vo8fw(9 hb*fo 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/sh .p+9rm+90nguz vxeliv, (ts on the surface of planet X where the zling.e (0,xtru9v vs9p++mh acceleration 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 planehv7,c *ou1.yq3 nnbo mt X wheub*1v3o7oqy m,nch.n re the acceleration 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 friend hor,o50:eb v;otp 6 qw7f m,ncholds a ruler between your fingers and releases it without b,o c m0eq75fro6ovwt ;ph:,n warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward atf mfg+u/nse;cgg /te*-i 1j- c a velocity of 19.6 m/s. What is its velocity after 3.; cs* mgi/nu f/fee--tcgj +g100 s?

  A bullet shot straight up re/ na+t,q,;0bnr saskqturns to its starting point in 17 s. What is the initial spees,q,;knr t0qba/n a s+d of the bullet?

  A ball is thrown straight up wi dsii c8gh9*.zth a speed of 36.0 m/s. How long does it take to return to itsi 8 zdsi9ghc.* starting point?

  A ball is thrown downward from the top of a building with an initial speed of 14p x/hi ekwhztha8czdt23: /3n-*tf)/( cz aew m/s. It strikes3ch2 ti/d ezxw*3/ea(zz/twa) phn8tf :h-k c the ground after 6.6 s. How high is the building?

  A ball is thrown strheaxsk *uznw/ r pka x 99/l4+kz:ekme7yz4: .aight up with a speed of 30 m/s. (only fill in numerical value:u4k:/ns9z.z xp7h +kze rky k9 e/xaa4*le wm in 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 strambp4r.d / z)ysight up into the air with a speed of 22.1 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 6 m above the point of contact between the bat and ball for the first time.  (数值)  $s$
(f.) Determine the time at which the ball pass a point 6.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is thel12jhd4 6,b gvgvxjos(7hh * w velocity at t = 1.0 s?

  In Fig. below, what is the velocity nsbpw,78 sbs1 elud- mew4z*ega4g*; at t = 2.5 s?

  In Fig. below, what is the velocity d lxjl*c. 0d:yat t = 4.0 s?

  In Fig. below, what is the velocity at t = 552it lzwqjk 8tu/n2ws5nj;1 wzh ; m 93mo;nzo.5 s?

  In Fig. below, what is the average velocity fro 6sbuxju8eoqt ic z(k4d18)9h2gq2dgm 0 to 4.0 s?

  In Fig. below, what is the average velocity f07e , kc . zj)aw,u5wywz4ruwfrom 0 to 6.0 s?

  In Fig. below, what is the accele5b*ha k /uw(zqration at 1.0 s?

  In Fig. below, what is the acceleratif1 uo2icye6kjl +k c18on at 3.0 s?

  In Fig. below, what is theynu /)+ltlu6 p -uq :+;uf8wy)kxhea e average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 t lo k3xeys -svwo*626co 8.0 s?

  In Fig. below, what is the displacement from 9bli 80m 2ogxn0 to 8.0 s?

Does a car speedometer measure speed, velocity sxb 2/ 8x-76cmzmfhszz a86ra? {speed|velocity}

  An object can have a varying speed if its velocil,*as dd 5w7bqlo2o: 8(pymcv6vsi; kty is constant.

  The velocity of an object can be negative when its acceleration is positw t7h9 3e3h1jytblu 2bive.

  If one object has a greater speed than a secone)wd scrb 2r4zq)5h,wd object, the first must have a greater )ehsqdbc ,5 wrr)42wzacceleration.

  Two cars emerge side by side from a tunnel. Car A is traveling with a sl5nqz-qkl rhxnk0/3 -peed 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 decreaslq5a8clnvs1)jf8 ; f. hjhr w1es.

  A baseball player hits a foul ball straight up into the air. It lelj n5ok4us)y (aves the bat with ank( u5)lso 4yj 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, h, jpi/ejz2(b-fw ;/ bdewy l i4:ttl2uow does it change if air friction is ignotz;( lt-fpe//id:ebj2w,4jl2y b wiu red?

  As a freely falling ; cl0eh2uo+rxfn,x :u object speeds up, what is happening to its acceleration, how does it change if+2 uc uxx hfo:;e0l,rn air friction CAN NOT be ignored?

  An object that is thrown vegyktkqmh(0,u:umlh; w 7 an py, g45l*rtically upward will return to its original position with the sm hga5kmpgu,*q, y; (nlut lyh47kw :0ame speed as 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 and nonzero acceleration at t2 b k475csf od.xgi3fbhe same time.

  An object can have nonzero ve ca/0 29fyhopnlocity and zero acceleration at the same time.

  An elevator moving from w-flv8 n(-s uj.h.pxbthe second floor to the fifth floor making no stops along the waynvspj . --.w(uhfb x8l has zero acceleration all the time.

  A rolling ball moves froe4 kdosk b(qd7 7j(-wjm $x_1=2.2 \mathrm{~cm}$ to $x_2=-4.8 \mathrm{~cm}$ during the time from $t_1=1.5 \mathrm{~s}$ 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 $t_1=-3.9 \mathrm{~s}$ is at $x_1=3.2 \mathrm{~cm}$ and at $t_2=3.9 \mathrm{~s}$ is at $x_2=8.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-v(ym) txvou g98 5qqw.6 b(m0dczetl(mile ($1 \; mile = 1609 \; m$) track in a total time of 7.1 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 gg8x*e r+qt23/0d y wfmzgy3v straight line, moving 113 m away in 10.5 s. It then turns abruptly and gallops halfway back in 4.5 s. Calculxy 2ey +383g0/gg*wzvdqrtm fate (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 fromic-pa), nj:kr $12 \; m/s$ to $24 \; m/s$ 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 fro1+oem2 od(q4tp+:4qro pqogym $18 \; m/s$ to rest in a distance of 66 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reacu *xq* nc+s:foh a speed of $27 \; m/s$ 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 tu (*h;y73jeqf vydr)rhe blocks to essentially top speed abouq7rf* erd) 3u(yh;yvj t $10.7 \; m/s$ in the first 10.1 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 cetp,f2e5)s mof $21 \; m/s$ to rest in 4.49 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m long on the highway. Assuminq/51ymsb 9.bp fqrymp. / n)8vb+cj aog a deceleratiormb 1yb obm/c. n+v .sfj/q5p89p y)aqn of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goinc -os6uxu)(y ag $25 \; m/s$ 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--cwg7n o/ jk5gm run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then accelerate 5jo gw-n7kc/g at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$