Suppose that an object travels from one point inza m;0rzds wwh8o+6 jnk/z-.apmpa9 2 space to another. Make a comparison between the displacement and the dp 8zh9ajmok/s dp .m-+0;nrzaa 2z 6wwistance traveled.

  When is the average velocityg(t/nl22ynu:x hl vv+ of an object equal to the instantaneous velocity?

  A new car manufacturer advertig3;8 tcnm uxkmo 68igj*jv6j/ses that their car can go "from zero to sixty in 8 s". This is a description g v/gj3x omt668k8jcnm*; j uiof

  An object moving in the +x axis experiencts .c noi8:t 2nrm6n5r(8p1 .gzvp,ehakxa. des 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 dowytrg/ utnw2 zwx-2zb;l ).gm3 ytp -)pn as it approaches a traffic light. Mayx pt n.wlg/w2-b;p)mt)zy 3tgzu-2r ke a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x dign )/kwy 8s*ngrection) begins to slow down as it approaches a traffic light. Ma kg8n)sy *wng/ke a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statement jv,/+ rvk0hjk concerning ikhj k,v0r/jv+ ts acceleration.

  If the velocity of an object is zero, does it mean that the accelewtd.c3hv3aw* tz *+e fration is zero? Support your answer with an . whca*t3e*3tvzf+dw example.

  Can an object's velocity change direction when its acceleration is constant? Skf9c*4bf k f ms8vl):bupport your answer with an examp kblfcb fk v4)9:8fs*mle.

  Suppose that an object is moving with constant accelera+mn oan e.-uijj q4v5,ip,as1 tion. Make a statement concerning its motion with respect to time+1 qo.,-isi naup54av,mjjn e.

  Can an object have increasing speed while its acceleration is decreasing? Supp. ujj-p, kr1madm)l. iort your a. pdki raj-,1)ml ujm.nswer with an example.

  Suppose a can, after an initial kick, moves up alonztko(4 2 y404 1p;z 9b8zkmjmozsrddzg a smooth hill of ice. Make a sta m k drmdp0otzoz4zbs;2z4( 89yz1jk4tement concerning its acceleration.

  Under what condition is average velocity equal to the average of ra7:m:/lwu grd; kz2r the object's initial and final w / mzklgdr ;7r:u2a:rvelocity?

  Objects A and B both start at rest. They both1;a(nc(nbyf d accelerate at the same rate. However, objecy(bnacf n;d (1t 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 restelu6t azu6 py6r2b),x. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance tra 6z),6x6lpturbe2y uaveled by object A compared to that of object B?

  When an object is released from rest knh0u wrq0p* i6x /bxv,k f0,qand falls in the absence of friction, which of the following is true concerning its motion6kk , *r xhv/bp0nqu0,q0fwxi ?

  When an object is released from rest and r75wv 5- ght.:yfw-lq)qqj)d1t fbp20uks f cfalls in the absence of friction, which of the followi5w 2uf-s)1f-):l t dvy7p.r 0 qbjwkghcftqq5ng is true concerning its motion?

  Suppose a ball is thrown straight up. Make a statement abou: z:mw fph;zzn 0f8w )mm:emv3t the velocity and the acceleration when the ball rmzpz 3;:hvm:0)wwmm :z en8ffeaches the highest point.

  Suppose a ball is thrown straight up. What is its acceler ,6 hizlq4ca2eation just before it reaches its highest p6iqhzca 2e, l4oint?

  Suppose a ball is thrown straight up, reaches a maximum h s5wu1.pxt 2 /qrnm9nheight, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is going q pnh1/ws9rn x.t25muup.

  A ball is thrown straight up, reaches a maximum height, then fa atkz 1ic -xs2or10mywve8*s3lls to its initial height. Make a statement about the direction of the velocity and acceleratiom1a3vio scw ery-8 *0ktz1s2xn as the ball is coming down.

  Suppose a ball is thrown downward in the absg7 x1 ildxtel.b090 ozb,z9yvence of air resistance. Make a statement concerni0t.l07xd g,vxzyio e1zb99blng its acceleration.

  Suppose a skydiver jumps from a high-flying plane. Wh.3pv4wlj a 0lccbr.7 tat is her acceleration when she she reacheslpjwac c7r03v .t4l .b terminal velocity?

  A ball is thrown vertically upward with a ssky/.1 x0kz1 .blrvz lpeed 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 seconl sz. /kl1y01.zkxrb vd 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 second later, ball)x0tkh 7tgz z1 vkvdx.o8a26p B is dropped from the same building. As time prv1t x x.zhta 80dzvpgk67k 2)oogresses, the distance between them

  Ball A is dropped from the top of a building. One second later, ball z78is 4 b*xxnt;zukd3B is dropped from the same building. As time progresses, 8nbz7 zx34*ut; sixkd the difference in their speeds

  Two objects are throcdqj:tbn(klnt- 2o7-c3 te ,xwn from the top of a tall building. One is thrown up, and the other is thkt7eo: njcqld,n 3bt 2t (--xcrown 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 bcgwyi n/*p+w:9m1 2ufb7 cxsu rick is thrown straight down from the same building. They are released at the same t7 1iw+ c*/nb:f9 us 2mupygwxcime. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity h,lde gf5g.5 kin the +x axis. The position versusd,.h5 fggk le5 time graph of this object is

  An object is moving wa8ckh:+ 1kgjxymld(:ith constant non-zero acceleration in the +x axis. The position1d xl+hka8g:j(y:cm k versus time graph of this object is

  An object is moving with constan9v ecj q3n0f3 fki*yi4dm.hnqdi16d )+zgsw 1t non-zero velocity in the +x axis. The velocity versus time graph of this oj )3nqkidw*e ih9c 4n zs1fi6301+qy dmf gvd.bject is

  An object is moving with constant non-zero acceleration in the +x*lm e-dnsnj 0q jrvz8g79 2y)j axis. The velocity versus time graph glnzj me-* 9jv nrs807) dqy2jof this object is

  The slope of a position versus time graph give f h:c7jj)2cx;cg ug-96ihl lvs

  The slope of a veloc ns/p+bg9o i,mity versus time graph gives

  The area under a curve in an accelsi-somjtzhro(pvz 9105t.2q eration versus time graph gives

  The area under a curve in a vepof2 y3gm1dfto ln30+np : ;bqlocity versus time graph gives

  If the position versus time graph of an object4yup ,gk7i9yuc2g q miz. kl*0 is a horizontal line, the object isk.kq imy2ui9ypg 47g0zlcu*,

  If the position versus time graph of an object is a vertical line, the+m3i2x 2 nftbdk5yjhle+ nm+;-dg4 y x object iskmyy db++nj24ftg5 -i mx; 2nl3de+hx

  If the velocity versus time graph of an object is a horizontal lin yw1lcow/5 :hre, the object is1 :5owyhr/wc l

  If the velocity versus time graph ofmsgj u-q*u0sx; +l .jc an object is a straight line making an angle of 30 degrees with the gmcsls* xjq;u.u+- 0jtime axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both the distance tsg,1)f:unb qv1adg7bn. drq 7 ravele7ndnu17 gbqbr 1 agd)v.qf:,s d and the magnitude of the displacement vector.

  A boat can move at 30 km/h in sv rl8h u,,t,7gzdma06iii ,ng till water. How long will it take to move 12 km upstream in a river flowin,rn6 dim,uzi 7hgt 0lavig, ,8g 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609 z2(5zfs+z+z+tvga kzm)

  What must be your average speed in orjfp bwccxz+xw7 tg:vv/z k04*l3v7iept:((rder to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. What itoe8h**edika3tm pbw0 pe 53*s the average speed of the runner in3tbd em0eea*8kohp5 *w ti3 *p m/s?

  A car travels 90 km/h. How long does it take for it to travel 40ih:;ugu e(uu; burh :b23ka7 hnh 6t.y0 km?

  A ly (light year) is the disn;x :-3pn srudtance that light travels in one year. The speed of light iu:sn- 3x drpn;s $3.00 \times 10^8 \; m/s$. 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 straiyl,afgtlz 37,x *wy9cght road and you look to the side for 4.0 s, how wlza,x yg,ft 9l7c3*y far do you travel during this inattentive period?

  If you run a complete loop around apqkx: / noyalv 3us2bq,c mjw2un 6u2z-1e9, an outdoor track (400 m), in 100 s, your average velocity isa ymz q:ne /ox2 v ,2wqkp-9,b6 ajsu1clnuu23

  A polar bear starts at the N cak h-1.kf;tc+f *chnorth Pole. It travels 1.0 km south, then 1.0 km east, thenthc .n fc1kc *;-fak+h 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 speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, thwg85.r gn(mdf en 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 was the bear's av8r5g.( g nmfdwerage velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles. It t4l oow8 noi:5then starts to snow and you slowwo olo:58 4itn 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 9r 8 l brbl)5fdf5gm/kkm/h. What is the average speed of the motoriskflr 9mfldr 5)bg8b/5 t for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her avh)b+oh1ob w opc1v,4 xerage speed for ,1+b ) wbvo1oxch4hop the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 25wf;uviaoy* 06 0 mi/h north for 750 miles.v*yao6 f i0uw; What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who rj2nazw7b 8qc9uns 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 leacj2 7b8n9awz qd 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 ay:z7:ub+ez wc fter 10 s. The car's average velocity during deceleration was 40 km/h. What was the car's deceleration w7zyb:z+uce : while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, ak2*2.we zsr.q fehrg .t the average rate of s2q.2kgr*zrefw he.. $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the r0b0c 3(/con o3 gzejawn/ l)s ,yjwj4a ;n+fnzate 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 acceleratiw -,jbw1 ; n h4v9khm0jkihx+es 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 constant acceleratio /+cjapt. 9 -o8pkahion opoat+ hpj.ka8-oi 9/c f $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 5.6 m/s experiences a constant accele,5geif m8fer+nw5 h0m ration of +mnwrhf08mi5 fg ee5, $3.7 \; m/s^2$. What is the cart's displacement during the first 7.3 s of its motion?

  A bullet moving horizontally to the right (+x direction) wi /b*wz+bqpchc,:qw n+sd:4n ith a speed of 396 m/s strikes a sandbag and penetrates a distance of 25.92 cm. What inpbqq*c isw:/c+:4+,z nbwhd s the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on lo((9h2- d m ccnmj2jxp;,agman aircraft carrier. It reaches a speed of 42 m/s at the end of xh(m cp( dcjo9alj2nmg-m2,; the catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant aq:3. 8lat0jw uzd ubn6cceleration 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+czl9l ld z8 +2g61prk1m ,3vdfoycy.rupb ) b to 80 m/s in a distance of 200 m. What is its average accele3gr+vlkz 2ybz r6c11l+9.mo dc)lbp 8dpuy,fration?

  An object starts from rest andledzcm5+ v-f+sy8ln 7 (s-x pd undergoes uniform acceleration. During the first second it travels 3.0 m. How far will it travel during the tms--f+v s (epz5cllyddx+n 87hird second?

  An object is moving in a straight line with constant acceleration. Initially 8. (aq/dunuwx it n.8 (uau/qdxwis 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 rest and acp.ifqq 9w 8wv0q+jh g)e o2p:vcelerates 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 -a7lm68(ktgbx f)reml q*z2 labout $5.0 \; m/s^2$ 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 traff 0wq4o9abuj, yel eu,32r,brnic light turns green, a car that has been waiting at the intersection starts ahead with a co2jn,,oqrr4wbu la u0, eeb3y9nstant 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 surface of planet X w7tiin n2 x4t6where the acceleration due to gravity isnw64 2x7n itit $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12 m saxp6+4w3yo x/s on the surface of planet X where the accelexo4 6pa y+xs3wration 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 upw3pe8h +plpb vg/ px/;u o1u5eas) et;jard with a speed of 15 m/s on the surface of planet X where the acceleration due to gravity i3/g ;lop;ppsut/1puaj)xv e5 +hee 8bs $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

  An object is thrown upward w8p l7cq mpmv43ith a speed of 14 m/s on the surface of planet X where the4qv8lm c3pmp 7 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 usualoh.,8vm0 ajah ly greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can yo8., ovamh0a jhu expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is its velocity h kua,ciua)2)ksm*i)h 6ni4 iafter 3k4iis,c))2mnhu*ih)i 6ka a u.00 s?

  A bullet shot straight up returns to its starting poijj3 w up4*wb1(fbf1 utnt in 18 s. What is the initial speed of the bul3(1 uwj1f4 bubf* wptjlet?

  A ball is thrown straight up with a speed of 36.0 m/q0qn, +s o2x4ew,l 1pinnf1w us. How long does it take to return to its ponw,l+wsi , q20q1nuxf4 en1 starting point?

  A ball is thrown downward fromx8a0wq2w hk)v7kq/ /yyi ke t. the top of a building with an initial speed of 26 m/s. It strikes the groundkh.qx7v820y atw ek ) /qkywi/ after 3.9 s. How high is the building?

  A ball is thrown straight up with a sphcwo9cw+5bz:bpyc .3 eed of 30 m/s. (only fill in numerical value hcob53+y:zbwc wpc.9 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 into+dor2 rirh r1ab+a7q6 the air with a speed of 31.6 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 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 = 1.0 sxqdw x)zov 5xo 1 meg9j-g62x5?

  In Fig. below, what 0a67ms8c h lzdy2qt kk4t5/9*llc ooy is the velocity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0 em**jztpgkm .6fww9r r-lj6; s?

  In Fig. below, what is the velocity at t = 5.5 pb2oqx)mn qmq e-aw.iu/4a: )s?

  In Fig. below, what is the average velocity from 0 to s( b8ukd.y3u)5g1/ca *biua nugn3ya 4.0 s?

  In Fig. below, what is the average velocmjju tu;o syu; 8o)6r(ity from 0 to 6.0 s?

  In Fig. below, what isc.s 1l ttqq3t m:i9ep- the acceleration at 1.0 s?

  In Fig. below, what is the accelb /wp uiu2p0**w 4dmcneration at 3.0 s?

  In Fig. below, what is the sb aa62 qe,y7f9p l d03n pmcm2b0xct6average acceleration from 0 to 5.0 s?

  In Fig. below, what is the averagkdh z p8z1l;rgp27oadl 7y32 he acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement fl5 hf202e9zrtdqui:b rom 0 to 8.0 s?

Does a car speedometer measure speed, velocityf(toap e 73z-s? {speed|velocity}

  An object can have a varying speed if its velocity is constant.)m2fn oe:ers90jh6 q*ldsn;p

  The velocity of an object can be negative whet)rfh/j7egtl1 iu * n0n its acceleration is positive.

  If one object has a greater speed than a second -pc05s e,l4auow7a goobject, the first must have a greate cls4,op7ao-5wag0e u r acceleration.

  Two cars emerge side by sido mr+ xt1qg+ 6hl7jpd(e 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 increasing in speed az6u j*7i,a2d m4wezbic6 drh1 s its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It leaves the ba)ednb q 87tr7coea0 k:t with a speed of er8q7) nkcd0t :o7e ba$120 \; km/h$. 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 upi,1ugp*g.,;u( li.xj zdvi p u, what is happening to its acceleration, how does p,i.;j z* .xu 1pdi(uguv,lgi it change if air friction is ignored?

  As a freely falling object speed asek y;.*nt6cs up, what is happening to its acceleration, how does it change if air friction CAN NOT nc6.sk;t *yae be ignored?

  An object that is thrown vertically upward wi 11n6jaba c4+1pzf tfill 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 bejbzi fnc1at1 a +4pf16 altered?

  An object can have zero velocity and nonzem, o2sjlatrzt)ka4 *0 ro acceleration at the same time.

  An object can have nonzero velocity and zero acceleratio7d7 lxbis- sb8(2vrq en at the same time.

  An elevator moving from the second floor to the fifth floor making no stops alonkktza704k(oh c,uss -c;r .svg the way hk, hstkk 7rvac ;4.(oc su0z-sas zero acceleration all the time.

  A rolling ball moves fromi axl bga:m0m cr(,. wcy)x-3y+to1 zr $x_1=2.8 \mathrm{~cm}$ to $x_2=-6.6 \mathrm{~cm}$ during the time from $t_1=2.3 \mathrm{~s}$ 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 $t_1=-3.8 \mathrm{~s}$ is at $x_1=2.9 \mathrm{~cm}$ and at $t_2=3.9 \mathrm{~s}$ is at $x_2=7.6 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete labb3ev8 z 2e/5a1tqv bzps around a quarter-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 strai3n0u3csx-a - )isjap qn+4p bfght line, moving 102 m away in 10.3 s. It then turns abruptly and gallops hala3x-p4+c3 q n sus0 nf)aipbj-fway back in 4.8 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 e/ rm1i b9-ngwny 3w,i$12 \; m/s$ to $25 \; m/s$ in 4.1 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 fromn 3 tzhxa:6lu: $17 \; m/s$ to rest in a distance of 73 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed of ;, ;kx0s7n nrt3 dgvn3axs bl+s)j5ac $30 \; m/s$ 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 h :uxh mbn5kjfn*y3f-;4c0 l ressentially top speed aboum*fjc3l4fny 5 h0nh;b -kxu:r t $11.4 \; m/s$ 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 uniformlyq 9 e es.t1lnd2 nbrl,7xwt8y8 from a speed of $20 \; m/s$ to rest in 5.51 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid sl.i/,ul c imhs8a5.jmarks 92 m long on the highway. Assuming a deceleratic.hj.ism5/s iu 8lal ,on of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a tru1:-mm pa oxwd- i3x3qhck 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).    $m$