Suppose that an object travels from one point in ocdz*1m r8 x ,e4zywn364jr yq.o pj8gspace to another. Make a comparison between the displacement anr*y8oz8c3xjp 4dq1my wo z,ng6 j.r4ed the distance traveled.

  When is the average ve:4colirds *umoq0)0y dz-a;f 4p bja4locity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "fromp)1 9w skwk(ul zero to sixty in 8 s". This is a descriptiok) w sk91u(lpwn of

  An object moving in the +x axis experiences an acceleratio4xuz )2elw :gon of $2.0 \; m/s^2$. This means the object is

  Suppose that a car travel zgkq57yd;6krv.n+ qr ing to the East (+x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleration.rkn5k;vrqd .7 zgyq6+

  Suppose that a car traveling to the West (-x direction) begins to slow dogz0o 034ngo* s2hbmjh wn as it approaches a traffic light. Make a statement cob0mhso4 *0zhg nogj23ncerning its acceleration.

  Suppose that an object is moving with a cok(cjgaw 8/bp,mxbei 7 27f u4nnstant velocity. Make a statement conce7cxkp7am b w/428fjeibg n,u( rning its acceleration.

  If the velocity of an obj qbqje:txf 9*cnj1( spe+ 69uua:1pxmect is zero, does it mean that the acceleration is zero? Suppor1 1(*e9f9:pm6ajtn + bp c xquuq:xjset your answer with an example.

  Can an object's velocity change directioen mh*q4 tsd:f e)eo;4j5g-irka 77ajn when its acceleration is constant? Supportfje 47 ) odeha7ngtkqijaer*-s 5m4; : your answer with an example.

  Suppose that an object is moving with constant acsdg9w0 b66hmzceleration. Make a statement concerning its motion 6s9 bwdg06mhzwith respect to time.

  Can an object have increasing speed wh:6 7*zfttnj(cx err/k ile its acceleration is decreasing? Support your an /rcrx :t*j(fnt7ezk6swer with an example.

  Suppose a can, after an initial kick, mo: ( w+86h kncyvddm6mmves up along a smooth hill of ice. Make a statement concerninghmm+vddyc866km: wn ( its acceleration.

  Under what condition is average velocity equal to the average of the 9u uf4f1jd(1gv,q hjnobject's initial and ffun fv( jj19,q1hg4duinal velocity?

  Objects A and B both start at rest. They both accelerate at the gua,e:z-m9 lhsame rate. However, object A accelerates for twice the time as object B. What is the final speed of objectae lu:9g-,hzm A compared to that of object B?

  Objects A and B both start from rest. Thec*v.x i ,9vmeml twq:)y both accelerate at the same rate. However, object A accelerates for twice the time as object B. v:,9mm.)vw*e tcxi lq 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 ab js+n)mr,oy9d * 2k: z:6rfjwcbmvr.zsence of friction, which of the following is true concerw jfmr k9*, r:o2yvr.zmd)6ns+z :bcjning its motion?

  When an object is released from rest and falls in the absence of frictios4d4+1 xrrsg+rubbc - i o/1ehn, which of the following is trueu/ 4orsg i cd14rr+- +bex1bhs concerning its motion?

  Suppose a ball is thrown *-f k xq.nc+wp-alue) straight up. Make a statement about the velocity and the acceleration when the ball reaches the hi. *pfknlae -+)q-cx uwghest point.

  Suppose a ball is thrown straight up. What is its accelev f57v+bj7ei s/eae 7oration just before it reaches its highee57ai /7e evfbv sj7o+st point?

  Suppose a ball is thrown straight upie ew,zpls; 16 iakqo /p;0xe5, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and aws;/i0,6ape5e1lxz kqp; ieo cceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, the0l6mm .-mt( cc x0by a*lce+bcn falls to its initial height. Make a statement about the direction of the velocity and acce6ml. cma*x -+ lcm0e bbc(tc0yleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a st(lvh:0vl4o b1oapt. latementl v0val(1h.plobo4 :t concerning its acceleration.

  Suppose a skydiver jumps from a highh(,0 d888j8mpwrk l+fvzd fhe-flying plane. What is her acceleration when she she reaches terminal velocmkfj0 h(h 8d,pr 88vd+8zwfleity?

  A ball is thrown vertically upward with a speed v. An identical second ball ixu rws0v8 t+:tcuhoh-( f0bn9s thrown upward with a speed 2v+r uh :tfw cx-08o0svn9tu(hb (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. One seconwd )6nyh,i qff.p9w m4d later, ball B is dropped from the same building. As time progresses, thew .)9qwh pfd46iym n,f distance between them

  Ball A is dropped from csyra3r6 usul/,sc62 the top of a building. One second later, ball B is dropped from thec/3u6r y scsus,6rl2a same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrownur 65ug99t w:vpxxeer ojg(po58 7ct9 up, and the other is thrown down, both with the same initial speed. What are the 5pxto j95gpx89cr67:gw9vtueo( u e rir speeds when they hit the street?

  A brick is dropped from the top of a building.k c ach8qmeq2j (:m8 vu5p+oq9 A second brick is thrown straight dowmek p h 89qcqmaou5v2c8( +qj:n from the same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constf2xay2nujbh , /1wu2oant non-zero velocity in the +x axis. The position versus time grj2 ofa/,2b 12hnux wuyaph of this object is

  An object is moving with constant non-z2z uik8kfa75 y4)cs (k qrm)gdero acceleration in the +x axis. The position versus time grapkg4ikrdc 8fyuk 5q ) s7(mz2)ah of this object is

  An object is moving with constant non-zero velocity ijgnl*f ) az- wev+/ws4n the +x axis. The velocity versus time grapfeavwsz gnj)/-4w* +lh of this object is

  An object is moving with constant non-zero acceleration in the +x axis. The vernc+ya,8qxl)(k8vndmy6 9cr ; aqb p:locity v69 n8 x b8+adplkr myn)avy:qrqc;c(,ersus time graph of this object is

  The slope of a position versus time grap/cmcw+ mk 3.68u jt,e+f avucth gives

  The slope of a velocity versus time graph givt+,zpnm6zii 7i qd6x +es

  The area under a curve in an acceleration versus2jayrx ky n3p.kt49y) time graph gives

  The area under a curve in a velocity versus timefoiy ;wo*ravkf(p60d2c rn w2o5j 2r0 graph gives

  If the position versus time graph of an object is a horizontaw p9t c(bliqc1 , 9o*cdh:k,aql line, the object is9,*(wlpq da 9qb,cc khi1co:t

  If the position versus time graph of an objectg aw l0aaa(l6o04em.b is a vertical line, the object ismela(6ab o 4a.0g 0law

  If the velocity versus time graph of an object isuovoymnu*q 9(am )b9 + a horizontal line, the object iso)*(q9ua + o9nbvmmuy

  If the velocity versus time graphau57 6nngo)i wr5 ngk( of an object is a straight line making an angle of 30 deg )n5n6(5nirk oauggw7rees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 a8 l9 zj/zx v9a2fj(/2yvzim am south. Find both the distance traveled and the mz/m a9 9axaf2lv2(y8ijj v/zz agnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it t :kdp6w h ucjc94/u0ydake to move 12 km upstream in a river flowinuud6ck0/h pc :wjyd49g 6.0 km/h?

  55 mi/h is how many m/s? (1 mi =.mv.auqqba v8ds.2qf y6ky 7(u jn5t4 1609 m)

  What must be your average speed in ordevj ) gvz6;n 3wgo p8t0ieibl67r to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) iyu h ;ptfw0o/7tq7.kny h:+y on 2 hours and 57 min. What i7;7qh/ :ok yo0puh+fw tt.ynys the average speed of the runner in m/s?

  A car travels 90 km/h. How long d299vu:c jxzrqoes it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one year. The mfn5 n +*9:xcqm pf..vinvjq/speed of light i9qpm:.n.n /vfxn 5+c*vjqfm 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 sgim/pj0a;6y92hn lsx b: is0 aide for 4.0 s, how far do you travel durixg6/mah9b0nil:j ip2ay; s 0sng this inattentive period?

  If you run a complete loop aroun/ ac7 ws(m ,ei1c/rlfj9cv3qzd an outdoor track (400 m), in 100 s, your average velociej/cwz9r( l,7 q3vsifac mc/1ty is

  A polar bear starts at the North Pole. It travels 1.0 km souj- rmwqs*i- v.th, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting pointsq-.*jiv mrw -. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at t:,) if -a nqhn6masbuk 3 4y-ceh*8oslhe 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 treqfn,3)6l8*a: on ac-ui-4 h hsmsybk ip takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles. xe,95y6)w say+v06 rnitzugy It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. 9e),6v50 y ta+6grwyszyxui n How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 kmlorw q: nrpu/ m:spkr;ei,60uul7o94/h. What is the average speed of the mqp4w0,76oop mn:srrki9 ul elu /:u r;otorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h x5js agz9-a(e at 100 km/h. What is her average speed for the tr-je95(sa gazxip?

  An airplane travels at 300 mi/h south for 2.00 hxe eaa2fi+li33 l.+ +hbrj7mu and then at 250 mi/h north for 750 miles. What is the average speed f 3mabhe.7+i3flj 2ar+l+u ie xor the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) f ged--9s e3+ yeynab5zbxal58or team A can run 100 m in 9.8 s. His rival, the anchorman for team B, can cover 100 m in 10.1 s. What is the largest lead the team B runner can have when the team A runner starts the final leg of the race, in order that gea5ne5d-s8bx9l ae3yb+- z ythe team A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 14 s. Thec)rstcvw7pevt.3 4b9 car's average velocity during deceleration was 54 km/h. What was the car's deceleracp.)t 9t3evscv7w 4 brtion while slowing down?

  An airplane increases its speed from 100 m/s to e 1wq(gh3b6ynz+o 9gd160 m/s, at the average rate of 9 zd3(o1h+y6ggewnb q $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate 7 )bf)j az )psv6nsw 04jbpt2vgtse9 .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 accel0v(by,y wskq+ ixho+) erates 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 fo,)te rslofa32: uuu l0r 10 s. It then speeds up with a constant acceleration oe: a23uu0us)tlr lof,f $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial 4a4; eolzal0kl*yx/qij9 , rtvelocity of 6.1 m/s experiences a constant acceleration of z4tq/yao*l r;il 409xljeka , $4.7 \; m/s^2$. What is the cart's displacement during the first 7.3 s of its motion?

  A bullet moving horizontally to m 5d7(rjlie2 pthe right (+x direction) with a speed of 264 m/s strikes a e52midr (pl7jsandbag and penetrates a distance of 47.82 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carrvg 88pjv(7.pq q9uco4 vs,td,x b. cz0gpqs; rier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assumi9cbtgsjv8qu pq84,zp v d,vxq7s.rc o .(;gp0 ng the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constantp7qvsw .n aphlhf/( ), 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 i43xj3,wana0c /zpxrxh+zvy3 ni k,f4n a distance of 200 m. What is its average accelep3xj x3rw +4/0xz n kcavanh4i,,f z3yration?

  An object starts from rest and undergoes uniform acceleration. D) ,q(rp.lc k5o ms(/qimc5 +p)otla hvuring the first second it travels 8.8 m. How far will it travel du5h/5picqm()km .os t)+ vr,ap l loqc(ring the third second?

  An object is moving in a straight line with constanus 8g 7bnzb2z:fh/j6aka -.zct acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during tha -/k7gcz.h b86azzf :ns2 ujbis time?

  A car starts from rest and acceleratkxj7+l*zl r: wmpe n4/es 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 canyruibkzi (nye 2/ 0/a (xw3jr.mf5e:t 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 beb, y.exhjy,r;en waiting at the intersecexh;y yb,j,. rtion starts 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 1bnq9kj7ef ,o;(zgf 9v-wsh n of 12 m/s on the surface of planet X wherek97fj-oq( b h,9ezf w1nn;sv g the 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 )/1u dnzz/wm0ov)l0cdz 8gzzof 12 m/s on the surface of planet X where u o1cgd//w0 v8)zznzmd0 zz)lthe acceleration 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 the surfail9swi 4k2 -ilvht- 7vce of planet X where the acceleration due to g2 iiswli--vhk tv 7l94ravity 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 su* e/oy p91nspy93 yoderface of planet X where theo9*e3y/ 9ny1 yeopd ps 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 usuallyo 4sc8qal4a yw/ 40ieo greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, hoe s8 ic0ywla4 o/oa4q4w far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a p yl-gts1)bn 7sg .n(mvelocity of 19.6 m/s. What is its velocity after 3.00 s(bnysn-.pgl m7t1g) s?

  A bullet shot straight up returns to its tfkbu :r,q2h. starting point in 7 s. What is the initial fhb kt:2qu.,r speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/:da1 +nse n*,hzqqy/w s. How long does it take to retsw 1neqa* dy,+hq n:/zurn to its starting point?

  A ball is thrown downward from the tom/q k5qjbaud1zfhv cdc-: 9520j-4 dupxo p;z p of a building with an initial speed of 10 m/s. It strikes the grodh5 o u 4 k;fav50c9/-jj-pudz2bcxm q zqp:1dund after 3.6 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in n3bl lwf/h2o x;zd s7(kumerical value in the blanks)b;o(7sxf 3 ll wz/kh2d
(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 air wqp qg:h. (ke(hith a speed of 45.7 m/s. (use $g=10 \; m/s^2$, only fill in numerical value in the blank)
(a.) Calculate the time required for the ball to rise to its maximum height.  (数值)  $s$
(b.) Calculate the time for the ball to fall back to the height at which it was hit.  (数值)  $s$
(c.) Calculate the maximum height reached by the ball.  (数值)  $m$
(d.) Calculate the ball's speed 3 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 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 the velocity at t = ipas(q, 27do r1.0 s?

  In Fig. below, what is the ve:yc20 7:sjb uvfmnjc:locity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0n/onxija5d r mi.0e 9* s?

  In Fig. below, what is the velocity at7x/)q j-k(ok kor7pgp t = 5.5 s?

  In Fig. below, what is the 5 0 m elhlnv7,x;ima, nu-tta8average velocity from 0 to 4.0 s?

  In Fig. below, what is :a qo5de sq1 g.0r 90rwxkxn1xthe average velocity from 0 to 6.0 s?

  In Fig. below, what is the accelj9q(/,g,fcom l3ih ob;gc4al eration at 1.0 s?

  In Fig. below, what is the acceleratii kf1v;cn27r;f ts a2ion at 3.0 s?

  In Fig. below, what is khbprdkbff-d7(:q/6the average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8. 5aiwwq5i8 w+rjvd/ d80 s?

  In Fig. below, what is the displacement f -y80erokc4(v14h fi5x y tpuerom 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {i tienvwc+; m ,0dypnl.5p. +aspeed|velocity}

  An object can have a varyn n ) t(6w 1f uvsnlrsu-;aemt9:,;jmcing speed if its velocity is constant.

  The velocity of an object can be negative when its aczooc. ys/1 tc .hasf/6celeration is positive.

  If one object has a greater spe .e0qt ccx62ikc,i 0 jyjk311)syrkdzed than a second object, the first must have a greaterq6s0kje0i j kiyt rz3c , ccxk1y2)d1. acceleration.

  Two cars emerge side by smft9r3 hm. c/uide from a tunnel. 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 incref+caygpulm/en3gior 6e98w . ;jgh+b9e j4x:asing in speed as its acceleration decreases.

  A baseball player hits a foul ball straight )bapq1f+3hmb up into the air. It leaves the bat w1b amp)3qf b+hith a 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 * ug ba)k,k;zmiqaj:e)awr:+ acceleration, how does it charj+kezamaw:a*),gi:ku;q ) b nge if air friction is ignored?

  As a freely falling object speeds up, what isd-4( ba7adsd otk:nx8zb 0o,d happening to its acceleration, how does it change if air friction CAN NOT be ixat ,7sdn-da(o db0k8bd 4z:ognored?

  An object that is thrown vertical,y88; x hull a55t3hc.wplvpa ly upward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be hhwc3,a58p 5;u lvtalxl .y 8paltered?

  An object can have zero velocity and nonzero acceleration at the same time.r4jr vg,qg6:o*a r (ux wgj.r.

  An object can have nonzero velocity and zero acceleration at the same m0ssyodh25o;time.

  An elevator moving frkejn,*s7 fm nk v)8hd:om the second floor to the fifth floor making no stops along the way has zero acceleration all thfn87 k:),k denjsh v*me time.

  A rolling ball movesh -z)(qt8 fvie4bt kw/ from $x_1=2.6 \mathrm{~cm}$ to $x_2=-5.5 \mathrm{~cm}$ during the time from $t_1=1.2 \mathrm{~s}$ to $t_2=5.5 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.8 \mathrm{~s}$ is at $x_1=2.0 \mathrm{~cm}$ and at $t_2=4.4 \mathrm{~s}$ is at $x_2=7.6 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-mile (xnon m;y *,-jq)ebq6b $1 \; mile = 1609 \; m$) track in a total time of 10.6 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its trainer in a straight line, moving 107 m away 5oge68;azzp 6z 4a k6j sj3bxti/ki q2in 10.0 s. It then turns abruptly and gallops halfway back in 4.5 s. Calculate (a) its average speed2jz86/k4gkxa bjzqz;e3i566s ta p oi  (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 c1n8,7koms to $12 \; m/s$ to $24 \; m/s$ in 5.6 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 fromd/ g0y+wf cl4l)z, cyyo 5goyce5,f 0o $16 \; m/s$ to rest in a distance of 83 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach (4y0tr7vz hd fa speed of $32 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $3.0 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of ),-e4 lnnjqvrp gx(h;q0l .ve the blocks to essentially top speed about )qelvn(0g ,pq jxh lnr 4;e-v.$10.2 \; m/s$ in the first 10.7 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 speh52ia-i.fw3.ad ; v(3 .efyoeo igsnbed of $19 \; m/s$ to rest in 4.21 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 0/ nfytf+sk: cib:t ,uu:7b pe92 m long on the highway. Assuming a deceleration0u: f,pb ibkn yutf+:7:tc/es of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck 7fv sb,vmy t(xq+f-r9 going $25 \; m/s$ 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).    $m$