Suppose that an object travelsgu+oqpjw c4 e7kr2we+g1q u.9 from one point in space to another. Make a comparison between the displacement and the dis7u2 pg4 +goqe1j wuqwk .ecr9+tance traveled.

  When is the average velocity of an object equal to the instj)n s2k;+q hnrl h onwuw24/n;antaneous velocity?

  A new car manufacturer advertises that their car can go "from zero toaoo.nv:e( y, tij1rj5 sixty in 8 s". This is a description ofey:rv t1oon(.jjai ,5

  An object moving in the +x axis experiences 1 sk5uwm+durbt*z / (oehx*4han acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x d qp ss(),el tkuxmown8 p*-25direction) begins to slow down as it approaches a traffic light. Make a statement concerning its accelerat(emp)p q2w ox n,tks5du8l*s -ion.

  Suppose that a car traveling to the West (-91b x;yer+ j d(f4v6hxkw1nzvx direction) begins to slow down as it approaches a traffic light. Makehv e( vk r1dx4bw+9yfz;n6 x1j a statement concerning its acceleration.

  Suppose that an object is moving with a cons pzpdfu19msz*)28 pof:n n l2xtant velocity. Make a statement concerninz*fd2:82n9pfx 1l)zp usp mong its acceleration.

  If the velocity of an object is zero, does it mean that the acceleration is z)l/s sn;ha4(u2w zlqpdh,ys ,t f ;jscz5(6oxero? Support your answer witwhy(o,/s pxuzt;sjlqs, )(d5;a62f s4znl ch h an example.

  Can an object's velocity change direction when its accelerath,,/ ,x zb ssfntp7y6tion is constant? Support your answer with an exas6p /,n tbhz,x fy7t,smple.

  Suppose that an object is moving with constant acceley0;hq 3p8s tykration. Make a statement concerning its motion with respect to;tqpk8s3yh 0y time.

  Can an object have increasing speed6 )b736c+f6 hvg ,cvks dhztba while its acceleration is decreasing? Support your answer wd6v6 b kg3f,)t h6s+acc 7zvhbith an example.

  Suppose a can, after an initial kick, moves up along a smooth kdvn ,y6)t1n8 kic0hj hill of ice. Make a statement con,6ihdky08v kt j1 )ncncerning its acceleration.

  Under what condition is average velopmnvtnkx504u a45 iim6+ -wbrcity equal to the average of the object's initial and final v0 5n5n bpuwi44v+ m kxir6-amtelocity?

  Objects A and B both start at rest. They both accelerate k w-x+1(xuhrpxn u,um:(ta 5j at the same rate. However, o,pw-m 5k1xr+au(:x uthxj u(n bject 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 rnczkw(4(y/;-as ; 7rbhsxihaccelerate at the same rate. However, object A accelerates for twice the time as obcw-kh(r(rsi xs7bhan;z 4;y/ ject B. What is the distance traveled by object A compared to that of object B?

  When an object is released from rest and falls in the absence of frictioncrl)6xb( km a2m1tcp5ju q;h7, which of the f rt7ux)ql maph1m(2; kc5cb6j ollowing is true concerning its motion?

  When an object is released frop8 92b/q zaifbm rest and falls in the absence of friction, which of the following is true concerning its motion?z qb9/bip 82af

  Suppose a ball is thrown nr7 cd (f9x8m,rpdh:e straight up. Make a statement about the velocity and the acceleration when the ball hr7 mr9ec (:,dnx8fpdreaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before it 7h mkz-fi 8zc98gbz /vreaches its highest poin8 c7z-ik8fm9gz hzvb /t?

  Suppose a ball is thrown straight up, reaches a maximum height, thc(w 4, l8+x*zgwa)o/cb bsqgv en falls to its initial height. Make a statement about the direction of the vecb ,8lx)soa v*b4( q+wc/ggwzlocity and acceleration as the ball is going up.

  A ball is thrown straight up, reache,ohmvv j+hvm ,k,:e/ws a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming downv/vhv wmj h+o,,em k:,.

  Suppose a ball is thrown downward in the absence of air resistance. Make a stat*p/i+bqsp,3koto pw - ement,pkto*bw3p oq- +/ips concerning its acceleration.

  Suppose a skydiver jumps tibqj: a1zqe-1 e efpai 4;-(;tg*a2ooaa*bafrom a high-flying plane. What is her acceleration when qqabi:j4eagt 1 -oaab(-*te1z*e ia;2p;afo she she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An ide9phm 2m h.;d+,myw 1hornbvu5z-m2lfntical 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; 9 v22w1 my5dhml mnzh+ou,fh .bpr-m higher does the second ball go than the first ball?)

  Ball A is dropped from the tkb3;l eq 3gz *j4ub* p+-deb6:iusnoxop of a building. One second later, ball B is dropped from the su6lesdjpq:* - b+no33e k ;*bi4ugb zxame building. As time progresses, the distance between them

  Ball A is dropped from the top of a): gk: r)g2rl qlrb2yf)apvy6 building. One second later, ball B is dropped from the same building. As time progresses, the differen klgf): )rbqrl) yvya:6pg2r2ce in their speeds

  Two objects are thrown f 3 lrogr42mpl;rom the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. Whatr opmr43 g;2ll are their speeds when they hit the street?

  A brick is dropped from the top of a/ qb1stb ra*w)sd v:4r building. A second brick is thrown straight down from the same building. They are released at : b)qard 1w*4 tr/sbsvthe same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving wity)ebdb0y0b w3n v2xe4h constant non-zero velocity in the +x axis. The position versus time graphdyeyvb 0b3x2b )e40nw of this object is

  An object is moving with constant non-zero acceleration in the +x axis7dom0 q as+/pwj*a hs(. The position versus time graph of this object d*/aha wmo+s(0 s7pqjis

  An object is moving with constant non-zero velocity inx nkj 54vz oar,-d-r2l;zi4vd the +x axis. The velocity versus timezdr -;a 2jlr,viokzdn v45x-4 graph of this object is

  An object is moving wp+o7q. epsynl5sy w 0)ith constant non-zero acceleration in the +x axis. The vel0p.y7 )sqo+ne 5w lspyocity versus time graph of this object is

  The slope of a position via+8vjpxreuxb( ;i wm7iz9cd8 3o p 8-ersus time graph gives

  The slope of a velocity versus time g+,bg7it,qfken0 whs h .-h ni7raph gives

  The area under a curve in an acceleration v787-l erlfy 7 p.d ffwhv-0hveersus time graph gives

  The area under a curve in wdqkbv)mops a71+:b5a velocity versus time graph gives

  If the position versus time graph of an o pr7sp:z5-m2- k 2gp yr0z/jn h;/co1cku peribject is a horizontal line, the object i u -2i-prcp/nck sz:5koz7;1rg0r/hpjeypm 2 s

  If the position versus i adat77jqb) b.bgw19time graph of an object is a vertical line, the object is 1qab 7)9tg bba7j.idw

  If the velocity versusz g60q8q2 gzr5dgh/vh time graph of an object is a horizontal line, the object i dqv/z gg8q2hrh65 0zgs

  If the velocity versus time graph of an s*/5 kly y.kee.vs6baobject is a straight line making an angle of 30 ds*/y e.5lyv6sb k kae.egrees with the time axis, the object is

  An object moves 15.0 /: bwguq4-dji0( r*pwz xukv.l56atu m north and then 11.0 m south. Find both the distance traveled and the magnitudiv (w .jp t5 u4ukl- d0wa:gxur6z*b/qe of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it txj-v9oj 3 iww5ake to move 12 km upstream in a river flowix5-ow v39j ijwng 6.0 km/h?

  55 mi/h is how many m/s? (1 mi hkuvkz/c :h5 /, /9.w0nz(ovf ndprvr = 1609 m)

  What must be your average speed in order to 9u5ro-m/d9zdn 8xh kutravel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. What :bvuha.fhe+f+ w th8ri7 ,d9pis the average speed of thfd+hh8 vibr+7 wp:9tf,.e haue runner in m/s?

  A car travels 90 km/h. How lon0 +pgj lrm/pg+g does it take for it to travel 400 km?

  A ly (light year) is the distance that light8 9b kqp,aac8o travels in one year. The speed of ,k89ba aoc p8qlight 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 thru5 a455df wjzyo sbu.1up:e6 e side for 4.0 s, how far do you travel udo re51p4 u f:y.w5 abzu6j5sduring this inattentive period?

  If you run a complete loop around an outdoor track (400 m), 8g82 fm(ybu u:hib k 0s535ypy jwpp,fin 100 s, your average velocity jpm:h i,53pw8y kfpyu 2b5f0ub 8gy( sis

  A polar bear starts at the North Pole. It d /wu 6cbu lr-r+63tnetravels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to itsn bwd3uect u6l/rr6- + starting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the Nor)q48 jkktk1jt e vdi55b4rt 7bth 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 war75jkbe) 44dk q85t tbit jvk1s the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h5 s+a*pvigq6*dun*gv for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive h*ud5*+ig vgsav q p*6nome after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h anp8orfs/e8a+mp v 9m tf ,ye9lxxz. /;ld 160 km at 100 km/h. What is the average speed of the motorist for this trivm xs x;,/9.p/yffa pr8et+e 8l 9mzolp?

  A motorist travels for 3.0 h at 80 kmrnr0lh;oxf /xcyp(l/ *ci1 7x/h and 2.0 h at 100 km/h. What is her average speed for the trip?cx x nc r/il/;*ofyl(x1p70 hr

  An airplane travels at 300 mi/h south for 2.00 h and thegu59c dbydy- bc0-vz4n at 250 mi/h north for 750 miles. What is the average speed for the 5 4gyc-ucb9 d0bd vz-ytrip?

  In a 400-m relay race the anchorman (the person who runs the last g kf.x eh3l/n-/ jiyor*sy6r9100 m) for team A can run 100 m in 9.8 s. His rival, the anchorman for team B, can cover 100 m in 10esy*nj /-og69 3ix.yhfk rl/r .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 lose the race?

  A car decelerates uniformly and comes to a stop after 11 s. Thh7 7, :aqpv *3xbljhnxe car's average velocity during deceleration was 41 k7*jna7:lbx3pxhq h, vm/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average r)n z/ l2dbjrd3ate of )drnbzd/l3j 2$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/hkpch+3 uzc,ij52nk)d gz 3iv* accelerates 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 accelerat rsa3utq 8y)+0avs .zues 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. iq5ay)qjg 6qw: xby p)we:85j It then speeds up with a constant acceleration of a5xib egq5wypjy86q: j wq:))$2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial vot:ticd; h,w(b )7bh gztv7zh6wzjfe w4 0(w6elocity of 6.1 m/s experiences a constant acceleration of ((7z dbwohhiwzb ;)7cvw6ttwtg:0hz4 fj 6 e, $4.8 \; m/s^2$. What is the cart's displacement during the first 6.2 s of its motion?

  A bullet moving horizonn8rg z.o;i8 uotally to the right (+x direction) with a speed of 555 m/s strikes a sandbag and penetrates a distance of 41.67 cm. What is the average acceleratinio 8o8;gruz.on, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on q-/f1lk6 : ok3 kblshxyjs74i 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 acceleration is constant, wqlb4y7sj- kf6ik l3/xo h:1skhat is the length of the catapult?

  A car starting from rest moves w bz8-+4whyn zwiknn8, /rla -hith 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. What is itsttxi1)dxf2 8a)8cgv( yp uj.y average ac gxi.tp 21fxyvuc(d y)tj88) aceleration?

  An object starts from rest and undv +vfbep cze3 u0s0b*-ergoes uniform acceleration. During the first second it travels 7.6 m. How far wi3vez-0c0fspbb +uv* e ll it travel during the third second?

  An object is moving in a straight ha g.)v:sm g/rqoa8m( line with constant acceleration. Initially it is trave:. 8a gs /q(gmroh)avmling 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 rest*fb/bhf4u hm4x /h)rm 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 roao496 v.oskuw:wc a5ql d 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 grck3 ga)qmd;;;b .oq0lbw3a yt :5zeiceen, a car that has been waiting at the intersection starts ahead with a constb3aeamlc bq5.oz);k tiqdw;:cg3y0;ant 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 rq:pevungx);88- m rr of 12 m/s on the surface of planet X where thrmn8 8g-er ru :vp);xqe 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 9uuldn9b 4qv 9surface of planet X where the acceleru99q9dul 4nbvation due to gravity is $1.5 \; m/s^2$. How long does it take for the object to reach the maximum height?

  An object is thrown upward with a speed of 15 m/s on theb0j0;9 /ol*u vz0iw: uqrlgdv surface of planet X where the acc9g0 ;blwr :u 0jlu0ovdq/ v*izeleration due to gravity is $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

  An object is thrown upward with a speed of 14 m/s on the surface of planet X w b,7i*i kh( yv ys0afbwme1*w,here the acceleration duyiv e *1,,w aiw(s0kby*bm7fhe 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 h o;3n;ng8xwq zolds a ruler between your fingers and releaswgz;n; o x8qn3es it without warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19q cc/s08fsh g4)im8gc.6 m/s. What is its velocity after 3.0s /88scqfihmc04g) cg0 s?

  A bullet shot straight up returns to its starting b/l484fm )9de kws/ag8 0i jb0awyhks point in 13 s. What is the initial skfdl8h ykbbg0/4sj8)m/w409s ea wai peed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. H:b0n al5ev-qzbxl36 hap(i * kow long does it take to return t a5aile3zpq(l06 n :xbk* vh-bo its starting point?

  A ball is thrown downward from the top of a building with an ine 40o) sjlasw2itial speed of 6 m/s. It strikes the ground after 3.7 s. How high is the buildine osjaw) ls024g?

  A ball is thrown straight up with a speed oi5x qm 80oc 8*infhwl4hk4/ngf 30 m/s. (only fill in numerical valuqkfm8oh8wlc4i0 5n*i h4nxg/ e 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 straight up tu9n/rz w82opn d0us5into the air with a speed of 40.4 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 1 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 9 m above the point of contact between the bat and ball for the first time.  (数值)  $s$
(f.) Determine the time at which the ball pass a point 9.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is ti: w 3ejkyya*2he velocity at t = 1.0 s?

  In Fig. below, what is the velocity u6bz1 8hd tj)qn:s(xu0 y 1ilkat t = 2.5 s?

  In Fig. below, what is the velocity at t = hs6pft *xkhrp3,b*;i4.0 s?

  In Fig. below, what is th/n,xvv,2 bnm xn /(fbsv45a nue velocity at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 tt;ckkgq9y 8q48e*vyto 4.0 s?

  In Fig. below, what is thu uby;1o3q)ui 94adean-gr 7 ze average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration at 1.n24kjvr( f, yb0 s?

  In Fig. below, what is the acceleranc;xohl(6n /yl.o8o x tion at 3.0 s?

  In Fig. below, what isadgt ,s* ;fm3x k0hrj* the average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleratiorh e mpa;0i2p,uy:i)on from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to 8.07g mxhq;fkb 1*mhpg3/ s?

Does a car speedometer mea.tzlxo0n + :: ;g5q9gxn.rua.1 cspvi7hpwnisure speed, velocity? {speed|velocity}

  An object can have a v/zb79bx k *ai j;.mwx go9x,bkarying speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is pos (8fvvm b tlw8wx.e*lbhk-r-8u t41jiitive.

  If one object has a gwf z*ju 6gnt)j :juf++reater speed than a second object, the first must have a greater acceleration.jjg+ z *un6)wjft+u:f

  Two cars emerge side by side from a tunnel. Car A is traveling with a sp (c*mb wmv4,o6-fyhj jcp04bteed 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 acceleratiib,shi9,2z ; -p2g l l*wxwdxevmnc90hp5j6 zon decreases.

  A baseball player hits a foul ball straight up into the air. It leaves the bat wk od(h aai+/zdpnds4 mu+h+ pya ;**5rith a(/r p +ddn do*4iahz+* m5uh+syaap;k 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-j- 5v ip0uzus up, what is happening to its acceleration, how does it chvs -5uzpui0 -jange if air friction is ignored?

  As a freely falling object speeds up, what iso(jk nf dmd km2736y*h happening to its acceleration, how does it change if air frict*kjd ny2om7d( 3f6mhk ion CAN NOT be ignored?

  An object that is thrown vertically upward will return to its origia,qbz 8 lcq,4enal position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will tlc, eqz, 84abqhis result be altered?

  An object can have zerooo,hk: a;s /td velocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero aci k6f-,lcu/u7r3d a j,brip *nek)jr;celeration at the same time.

  An elevator moving from the second floor to the fifth floor vt 2xv8gqw 58 9t6vrkumaking no stops along the way has zero accelerati t2vuk88rqt vgvx56w9on all the time.

  A rolling ball moves fr6 s4zh/f/4m x,pvxktxom $x_1=2.4 \mathrm{~cm}$ to $x_2=-8.5 \mathrm{~cm}$ during the time from $t_1=2.4 \mathrm{~s}$ to $t_2=5.6 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.1 \mathrm{~s}$ is at $x_1=3.0 \mathrm{~cm}$ and at $t_2=4.2 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quara v4rvr:zv 2))to xjp4ter-mile ($1 \; mile = 1609 \; m$) track in a total time of 10.0 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 lin91s)jd.f e rl;eoe( nz1 2srnde, moving 105 m away in 13.9 s. It then turns abruptly and gallops halfway ;n .selr)dznsejr(9 1ofe12d back in 4.5 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 from v1vk aonvi4kc e105(p $10 \; m/s$ 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 fromrn/.nw 4k qy;-8zaduz* d4aky $15 \; m/s$ 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 of.qlh*zo (n y/o $33 \; m/s$ 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 blc q hfmk69q*:amea,t2ocks to essentially top speed abouthk:m6e9tc m, f2q*aaq $11.0 \; m/s$ in the first 12.2 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 sp 11lmce yr4cr9eed of $20 \; m/s$ to rest in 4.55 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. Anaoa u61 b3w-w*gqpa :5o3awissuming a deceleg:i- pa3bawa6wn*oq513ou wa ration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck go+ip,;tam, b hying $25 \; m/s$ 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 lqzop gpm:;+*ca 8q *uness than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then accelerate at poc8:+ *u aq pg*qmnz;$0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$