Suppose that an object travels from one po6sx g21. iwzoy:j;ozdint in space to another. Make a comparison between the disply6x1owz:ogdjis.; z2acement and the distance traveled.

  When is the average velocity of an object equal t76cpj)b9zesjsg1z 1f o the instantaneous velocity?

  A new car manufacturer advertises ,q2s )zn;d+ t rsqas9t r1+nfqg/ ujs+that their car can go "from zero to sixty in 8 s". This is a descriptiozt s+qnuqf) dt+gj+r1 s9rsas n,;2/qn of

  An object moving in the +x axis experiences acv h7 4nyi4zi+bt7d;s n 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 +2g bde ynt9o1c5wd+u s6q- xsdown as it approaches a traffic light. Make a statement concerning its acceletsg1d +- 5ned2q +wybo9csux6ration.

  Suppose that a car traveling to thf g )bu*jvn,8ze West (-x direction) begins to slow down as it approaches a traffic light. Make a statement concerning it jbn*u,)vf8gzs acceleration.

  Suppose that an object is moving with a cons*,nb zv0e9wfj tant velocity. Make a statement concerning it,f ezn 0w9*jvbs acceleration.

  If the velocity of an object is zero, doeydzo:*(,nq5/u p bi qis it mean that the acceleration is zero? Support bi*/,q qd zi:ou(pyn5 your answer with an example.

  Can an object's velocity change direction when iu:t7x3viqw ,/t7fg 0a+oej-b yg+bfkts acceleration is constant? Support o7-tg 7 k wfbga+tf+bxqv: e/j,3ui0 yyour answer with an example.

  Suppose that an object is moving wpnc-m ypf4k .fmjh;fd8-qwwj/*e9 3oith constant acceleration. Make a statement concerning its motion with respect to ti k4wfqomp. pjy;-/m jhd*3 e98wf-cnf me.

  Can an object have increalj-1d pm3nqz,z lw 93zsing speed while its acceleration is decreasing? Support your answl wd3q9z-3mz, p l1nzjer with an example.

  Suppose a can, after an initial kick, moves up alohenl zq0u q6h) 5u(ru-ng a smooth hill of ice. Make a sqneu zh- 5u6()qhur 0ltatement concerning its acceleration.

  Under what condition is average0tohyvi303 btqu0 av hiu*5 l9 velocity equal to the average of the object's initi3ht09y 5otuib v0 iu*ql0h3aval and final velocity?

  Objects A and B both start at+rb0 okji0tem vy 56j* rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final speejrvjmo+e*t5i 0 ky60 bd of object A compared to that of object B?

  Objects A and B both start from eu87glx5ml,.fz t+mpo5v1 fy, sfy)a rest. They both accelerate 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 thatftovglxy 5ye m .zul5) 7mas1ff+,8,p of object B?

  When an object is released from rhx()to oz7ci2shibr 7--jnr 9 est and falls in the absence of friction, which of the following is t 7 - rsh)znb o7iji9or2(-thxcrue concerning its motion?

  When an object is released from rest and falls in the absence of frxf7 zr6 qfk1m1l, lqs-iction, which of the following is true concerning-x lr qfzs1l1 7mk6,qf its motion?

  Suppose a ball is thrown straight up. Make a statement about the velocit6ikg1g*dx8q i se/x 3fgnle2:y and tl sigdxienf8 x /3g1q gk*62e:he acceleration when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What if7-jc+sq j f6p;7psba s its acceleration just before it reaches a;+pp7j6jsfqb7cs -f its highest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then fallsnahdd vfcqg z17/- fq35ist 4) to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is going1 f f5qnhav4t-/zqs dig3 7d)c up.

  A ball is thrown straight up, rtb qa1bpz;,4 heaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming1,b4pt;h bzaq down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a stgy/ 8w 2(yiu dtw p l3vlw0;;g)uqcil;atement conce wqlp y)3(i2lc8gwg; ;;t/v uwuldy 0irning its acceleration.

  Suppose a skydiver jumps - lzjqq/mpk9 xglztv4m9u y85fx ;5+hfrom a high-flying plane. What is her acceleration when she s9+55htzx;myzm/xfg4 lu9k q-p l8qvj he reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identical second bjtt31x1 kz9yds+b1iq37y ivp all 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 higher does the second ball go than thjqz1tpbix33iv d y 7tsy9 1+1ke first ball?)

  Ball A is dropped from the top of a building. One second late .r npxzp9w5s/( zedle2fpm2:r, ball B is dropped from the same building. As time progress wpms: r(2 expezf/zn5d.p2 l9es, the distance between them

  Ball A is dropped from the top of a building. One second later, b-0ts 0l1ym34wl wxkutw* , mupall B is dropped from the same building.s kupu yx 43l,01*-w0twwm ltm As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall ,koa73vj4n8obdka d *building. One is thrown up, and the other is thrown down, both with the same initial speed. What ,3d ba7o8ndj*a4okv kare their speeds when they hit the street?

  A brick is dropped fromu /p o*d:b)/ dnedupt) the top of a building. A second brick is thrown straight down from the same buildi /d)deo bnu)p:dp/ut* ng. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +u fei/6 3mbk0l2k b l5jb0+lpgx axis. The position5/lbkj6k0g ilbum3 f02e pl+b versus time graph of this object is

  An object is moving with cons5t3-j6cc; +m4:1udgqqqm was e cq q;stant non-zero acceleration in the +x axis. The position versus time graph of tq; 1mm4qgqcuc+swj:3 5q6s q a;-ec dthis object is

  An object is moving with constant non-zero velocity in the 9fnj2otbs3 y4+x axis. The velocity versus time graph of thj3yfobn2t 94 sis object is

  An object is moving with constant non-zero)cw dm r. fr9*r dosdgtdr26c87:e 1wz acceleration in the +x axis. The velocity ve*rrf2omdw.6:1)sd e7 d z cd rwtrc89grsus time graph of this object is

  The slope of a position versus t.w;)f+ ewxahy ime graph gives

  The slope of a velocity verwyt p4lla- 1qdsz5di/**ge 5ksus time graph gives

  The area under a curve in an acceleration versus tktg c oksz0g gv,9u7521vmk o;ime graph gives

  The area under a curve in a velocity versus time grab dw5 +ogik let4 5j4qx-23uq3h0graz ph gives

  If the position versus time grap20 nx80x d dwo4psc88py-hs(r td avr)h of an object is a horizontal line, the object ir-p8)8xd0 a wvsd8 ohn4 ds2pctrx(y0s

  If the position versus time graph of an ob/u)ze a,/ cfmr9qzrr4ject is a vertical line, the object is94 ,qum rarcez )/rf/z

  If the velocity versus time graph of an op58wh da9 bpcdp+2kp/bject is a horizontal line, the object idh2dpw pk 9p8/+5bpcas

  If the velocity versus time graph of an object is a straigm4uu(/qie: ftht line making an angle of 30 degrees with the time axis, the object isu :/tf uiqe4m(

  An object moves 15.0 m north and then 11.0 m y3 *t;qq3lftx south. Find both the distance traveled and the magnitude of the displacement vecttfqt ;3x*l3qy or.

  A boat can move at 30 km/h in still xjnpgm +g2g71z*hm 4 bgu .s)vwater. How long will it take to move 12 km upstream in a river flowing 6.0 km/h.4gx ng)mspg mg1h7z 2*vj+ bu?

  55 mi/h is how many 7oe.qc;x44a cntf( f rm/s? (1 mi = 1609 m)

  What must be your average speed in orek ci1hki6jg /k v3;l8der to travel 350 km in 5.15 h?

  A runner ran the marathon (approximate2x lx.hic5)za ly 42.0 km) in 2 hours and 57 min. What is thx5clxa.)2i z he average speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to tra 3 q95fndcnkw2 aci91evel 400 km?

  A ly (light year) is the distance that light travels in one year. The spa fbcln54qgzwy99x5k):3( ct g c pp,weed of lightc3pag5p 4c9,zxt9qc5k :fg w(b n)l wy 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 p.xq:0 hj42ovg/lb ov straight road and you look to the side for 4.lvh2 v:bqgo0 . pox4j/0 s, how far do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, youen/za, *ie 3eqr average vele *3e ,/qnezaiocity is

  A polar bear starts at the Nortr.u(tv n ,(qbah 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 t, (.tarubv (nqakes 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.+/ 69hemdzimr0 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 was the bear's average/heizm 9dm+r 6 velocity?

  You are driving home on a weekend from school at 55 mi/h for kbzd67qoqqcsue 8757+ m+rqc110 miles. It then starts to snow and you slow to 35 mi/h. You 6qcocz7 k+7sq5 m7b 8qqdreu+arrive home after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 kjb.wpcpvfs8mbw; :y m:5pb9 4 m/h and 160 km at 100 km/h. What is the averagy::f85mp 4; vwcmsb.wbjp b9p e speed of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What irf)d+vu1 2i6 ,mkfh abs her average )fmai,6f2k uv hbr d1+speed for the trip?

  An airplane travels a je;zu(i: dpb+t 300 mi/h south for 2.00 h and then at 250 mi/h north for 750 miles. What is the average speed for the trd:pbj;ez +i u(ip?

  In a 400-m relay race the anchorman (the person1rkj:mw uvlt jc:)45p 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 of the race, in ordel1:tv )pw 5rkc4: jjumr that the team A runner not lose the race?

  A car decelerates uniformly and fcxgb6p-+l- * wd+ig ccomes to a stop after 8 s. The car's average velocity during deceleration was 44 km/h. What was the car's deceleration wfpx d+c* l-+-6wbgic ghile slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the averageoh8 v8emrp 2:kvc s(jmw uy*22 rate of e 2v:2uhswmcj o(mr yk8*v p28$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/nza 4j bq6ls. kl) 9.v2ghm;+r uya6fyh 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 reyvo* ;y( 1tl +bleq0xwst and 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/stari-)efw +: ,qgc dj* for 10 s. It then speeds up with a constant acceleration dc+*tqjfae : i- r,gw)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 7.4 m/s experiences a constah*fcvd-+j0h xnt acceleration ofjv*-x+d0fc hh $4.6 \; m/s^2$. What is the cart's displacement during the first 9.5 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a hd94 lmz* svi(;15cdbfjahy z.i/e d *speed of 334 m/s strikes a sandbag and penetrates a distance of 94.14 cm. What iz/9hcbajd4 5vfdy1d;(ilmsiz*he* . s the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircrzvcwir8g2 v/wu .vt8gap9qkip ; c e45 bl,v5,aft carrier. It reacev.8iiaplc gb52rvcw;4 vtz g u8,9/k, p w5qvhes a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from r c(f 0h 4yc/d3apnaqz8,dd6x 3w:kkmqh7 :vt cest moves with 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 ddbk.s gh3f zo; 6z,3ujistance of 200 m. What is its average acc3gd,3 ;zsz bu k.jo6hfeleration?

  An object starts from rest and 0sy5 js;o9num undergoes uniform acceleration. During the first second it travels 9s ;nus5j mo0y1.0 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. s.a ) wn4tf 5iziw9evc1,5xs fInitially it is trave5z n ,fwv9wi.ex 4ss5)ic1fatling 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 accelerates uniformly a.to, lgrl q0c6t $3.0 \; m/s^2$. 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 onpb1 x*57zr:-f1 ilscxj a 9fyo a dry road 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 d;.uznfx3 jr+ 1( n+eyq(c hvc esh46ygreen, a car that has been waiting at the intersection starts ahead with a constant. ye(6x ur f;he( nq4hc3sdzy+v+1njc 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 withnlkl4tyt*r*+ a speed of 12 m/s on the surface of planet X where the acceleration due to gravity is y rkt*l4ln*+t $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12 m/s on the surface oox1w01ckscm/ vv ns cs n4j0b;kmx.59 f planet X where the acceleration due tmn1 j4o9cx5ms/ ;0kcnbkss0x.w1cv vo 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 sur 6 ytjp3+k+jwip4y qj8face of planet X where the acceleratipitq wj 8+yy43j+pkj6on 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 surl d6; 9dh*1jvce)j cc4ybqg8 5uwxxp 4face of planet X where the acceleration due topdc 4uxe8q64x dc jgy*1hl; )5cvb9jw gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually 76 zdmce5 e)y /d.na4taqz l)ogreater than 0.10 s. If your friend holds a ruler between your fingers and releases it wiz)d aqz4tda o5e7e m/ly.6n )cthout warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What is itsa tbli omxn5m z(1*4c7 velocity after 3.00 s?mita7 ln ox5*1bc( z4m

  A bullet shot straight up returns to its starting point in 19 s. Wha 8gvhy,5o,/igre vp.tt is the initial speed of the bvy perg. ,58v,i/hg otullet?

  A ball is thrown straight up with a speed ofz7qwas,uc1w -eyx)k ) 36.0 m/s. How long does it take to retu7cexs1kw)zw q)-,y aurn to its starting point?

  A ball is thrown downward from the top of a building with an initialcz r w70r,qg5y*dcn9i speed of 6 m/s. It strikes the ground after 1.7 s. How high is the buildr*59 wy c 07ncrdzqig,ing?

  A ball is thrown straight up with a spe (mx t x,a+gsjrc:(0yged of 30 m/s. (only fill in numerical value in the blan+jxy(mc, xs(:t0r gagks)
(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 ta8fz-dxf;g rgi ,h 4wi,hp;5 nhe air with a speed of 38.3 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 8 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 8.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1.0 +gpat;lj xiv7 9; 4qdfs?

  In Fig. below, what is the velocity atv jyg7 /o45i/dsrc5ak t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.0 fmn6gatbv i 1 bl m3,576fyrs+s?

  In Fig. below, what is the velocity at t = 5.5 s?j;oqy.g;vl; j3pa 1od

  In Fig. below, what is the average veln7b0 g 7qv)wvnocity from 0 to 4.0 s?

  In Fig. below, what is th-py7j8l hpyrs cv,4 a-e average velocity from 0 to 6.0 s?

  In Fig. below, what isk)cv zt6)yjo5 yh:v b* the acceleration at 1.0 s?

  In Fig. below, what is the ,b9s8kkq, oyz acceleration at 3.0 s?

  In Fig. below, what is the an--h *2kcewyc. mw lwn*bpt:4verage acceleration from 0 to 5.0 s?

  In Fig. below, what is the averaytov+-c8b8/u6d i 0 cainyfc-ge acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement f4s 6(s b4lgxdorom 0 to 8.0 s?

Does a car speedometer measure speed, (dcoc-v d jp*4zkkt -;velocity? {speed|velocity}

  An object can have a varying speed if itw,jn kxx00u,nbu7f u2s velocity is constant.

  The velocity of an object can be negative when its accm)d y/xa r59sueleration is positive.

  If one object has a greater speed than a second object, the fmezrz.-mwj7 6 s7wk9u irst must have a greater acc7wm jmekwz 96 7z.r-sueleration.

  Two cars emerge side by side from a tunnel. Car A is traveling withmt /q 8ma4dpf- 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 j yahh7 ln.w6.j)c9jaacceleration decreases.

  A baseball player hits a foul ball straight up into the airqmx:h 9yp j9bd841tgr . It leaves the bat with a 9 4rpq91mbtg :jd h8yxspeed 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, wu t,j..arofuxrgo*c(.dm ria s 449 ;rhat is happening to its acceleration, how .r4*9m , rot..j(rs ria gxfadu; cuo4does it change if air friction is ignored?

  As a freely falling object .* gks)(yadarspeeds up, what is happening to its acceleration, how does it change if air friction CAN NOT be ignos) ka(ry* d.gared?

  An object that is thrown vertically upward will return to its original positionvsj :5ihw -3xmbq,aiym)l ((d with the same speed as it had initially if air resistance is negligiblj a 3,):lwqy(sb(5 mvihd-ixme. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonz(a y jtva4/ywfu/3r/vmsl p3-wcc/p7ero acceleration at the same time.

  An object can have nonzero vefai f867k:: u5u tiyjmlocity and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floo/rz jmuy i97q*r making no stops along the way has zero acceleration al/u7qymij* r z9l the time.

  A rolling ball moves frogxw7sa (t d9p;m $x_1=2.1 \mathrm{~cm}$ to $x_2=-5.0 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ to $t_2=5.4 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.8 \mathrm{~s}$ is at $x_1=2.5 \mathrm{~cm}$ and at $t_2=3.4 \mathrm{~s}$ 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 a k3mftf6ze rug+( gq3t.ph14 ($1 \; mile = 1609 \; m$) track in a total time of 12.2 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 strm0mv (wym*erz0 z / iy 5n-mz2o*b:shgaight line, moving 95 m away in 8.9 s. It then turns abruptly and gallops h5ny2z-mwhmm0:ob zvi e * rsy(g*/0zmalfway 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 froma7p7z .px abc3 $12 \; m/s$ 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 from 87anelos 5qrc9bh 39d $16 \; m/s$ to rest in a distance of 76 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a hoko nz* 9v5- 6z+fcmykstk, 5*i,tdh speed of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.1 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can bursvx 7hof4-8xn8zkb17 /fy u r,ohdti b-t out of the blocks to essentially top speed aboutdhnyiro- 7vbbx8f7 h1ouf 4z- /x8, tk $10.6 \; m/s$ in the first 11.1 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 uniforaig a8,4apoy5 mly from a speed of $17 \; m/s$ to rest in 4.09 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m lon kpzaf*,64d ynqw ,kk+g on the highway. Assuming a decelp4 +wz*ad,k kynq 6f,keration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck going dd2, jay7wpyz 0w 2r5h$25 \; m/s$ 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 less than 30.0 min. Aftergkj n16)w4tr e exactly 27.0 min, there are still 1100 m to go. The runner mu tw gr1jk6)e4nst then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$