Suppose that an object travels from one point in space to another.5ytdezx/71n a Make a comparison between thedty ex5z1/n7a displacement and the distance traveled.

  When is the average velocity xq*hy2t 3y;en of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "from zero to g ,shoona0k0daf6hc 4zk0nr130+nk xsixty in 8 s". This is a de0 nksn ad0rghc f ,xnza6kh0401oo+3kscription of

  An object moving in the +x axis experienjdyz w/syp(o( 2g m,- 5i:7+dsnqway xces 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 down aswe)b(*uf o;rxkv-f1g.q8me n itee.*nff1o v;g k)w(m-u8 qxbr approaches a traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction;t 5:7g gb/jpkdkz5rj ) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleratio 5pkt7gjdg /z: r;5bjkn.

  Suppose that an object is moving with a constant velocity. Make a statemew rvk1(dlz i5r,o3nl9nt concerning its acceleration.liv onwr5z,9 rl1(3k d

  If the velocity of an obkyzmj5/6zdt s1 p8 qe6ject is zero, does it mean that the acceleration is zero? Support your answer with an exek dm 5t6qz/pz s1y68jample.

  Can an object's velocity changc+3k8 su4t khwe direction when its acceleration is constant? Support your anssthk c384 u+wkwer with an example.

  Suppose that an object is moving with constvbmupi1v 2lw:0 (3ed hant acceleration. Make a statement concerning its motion with respect v: delh1ib3(0 uvpmw2to time.

  Can an object have increasing speed whin7kp j oyw,h/7 d 7tw.x9uq8djle its acceleration is decreasing? Support 9y8h7xou/k7ndw.djqj p 7 , wtyour answer with an example.

  Suppose a can, after an initial 9 :voky3z76x u5os-.c irrnufkick, moves up along a smooth hill of ice. Make a ns 9xvc-i ufokoz:rr63.75uystatement concerning its acceleration.

  Under what condition is average velocity equal to the average org fe+l se+;bq; 3nx0cy4hcz ;f the object's initial and fi+brscnce; ;eg;zfy+43x0lq hnal velocity?

  Objects A and B both start at rest. Thxe-cwy 7h)x- y azy:0bey both accelerate at the same rate. However, object A y 7xy--bxa: ce 0)whzyaccelerates 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 accen((nd1(udh fnlerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A comparen 1hnf(dn(( dud to that of object B?

  When an object is releas5) ,o yk kf(u4sum0hbwed from rest and falls in the absence of friction, which of the 5 swhk0uy)bo kf4(,mufollowing is true concerning its motion?

  When an object is re 4wa2 z rqf*ip6x.n.xsleased from rest and falls in the absence of friction, which of the following is true concerning it nrp f .*ixw4q62sza.xs motion?

  Suppose a ball is thrown straight up. Make a statement about the velocha zryqueoxm-w-6-/f1g1 gw- ity and the acceleration when thm6gfxzq/h1-ou -eaw-yw1rg- e ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its a51;pk m) ab gv.duwd3vcceleration just before it reaches it bk. 15vm)gpw3duvd ;as highest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then falls mptntze+cv56dkb/ 30 to its initial height. Make a statement about the direction of the velocd0 ept6 c+ tkmb5zn3/vity and acceleration as the ball is going up.

  A ball is thrown straight uyq 7,0mqfnk5t ft4w- up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is comin-k ft qq570ywuf4 mn,tg down.

  Suppose a ball is thrown dowbcfv+rl()bkd2t s 7x0j 5jp)bnward in the absence of air resistance. Make a statement concerning i)+frj x5 7lb ks0b(d )jtvp2bcts acceleration.

  Suppose a skydiver jumps from a high-flying plane. g :m5 k(6 2d-osmhco whcs6/oc What is her acceleration when she she reaches terminal velocic: g2 - /5o6chcdwsso omhkm(6ty?

  A ball is thrown vertically upward with a speed v. An identical second bm7t di dwtkgb8d/3tgy99f/) ,oq; xhdall 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? (Ho f/xtdhg);ddwq g ot3imtb/d9k,y9 87w 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, ballqtev8 1adu :f, B is dropped from the same building. As d, 8atf1ve:qutime progresses, the distance between them

  Ball A is dropped from the top of a building. One second la8kz t8e) kyrhr+ sa3i9ter, ball B is dropped from the s9 yr+keth8)skir3za 8 ame building. As time progresses, the difference in their speeds

  Two objects are thrown from the 2 rjq4/q (kxm pe,q 4,hlt7ozbtop of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hip qx2k/ 4bqh (rqz,7omle j4t,t the street?

  A brick is dropped from the top of a building. A secz5j2c ntuk654am u8-agb kma;ond brick is thrown straight down from the same building. They are released at the same time. Neglect air resistan54aja6zb 58uunmkkt -m;c 2a gce. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x ax2 c .2wepj4u94x ik.r 3a5ghn azhtcg.is. The position versus time c .u3g jw.4 kta ar4h5zx2e p.gch92nigraph of this object is

  An object is moving with constant non-zero acceleration in the +x axis.smh, pqv 4vu 0an*a:)/mpzm0g The position versus timvag mu0)4qs0*npmap zmv, :/he graph of this object is

  An object is moving with constant non-zaprp-(-ch- 4n 0pltnxero velocity in the +x axis. The velocity versus ta cp- -4hx -(trnplnp0ime graph of this object is

  An object is moving with c*ajosn+ sx., 3fvqy5k onstant non-zero acceleration in the +x axis. The velocity versus jyn3x, fv5+.aos sq*k time graph of this object is

  The slope of a position versus time grapp.vj sd1m8 0o dcfte-3h gives

  The slope of a velocity versuhom;+oejo; iitt )ydlm.kma+k /) dpg:)+* jts time graph gives

  The area under a curve in an acceleration versus time graph giv mf1gw*m*lmx+h01ko d es

  The area under a curve i,) : hfjyjl,aozyn9r9n a velocity versus time graph gives

  If the position versus time graph of an object is a horizontal 0)b+ayfhm7e p1 wx 8yoline, the object a8b)07p+ h1xyfme ow yis

  If the position versus time graph of an object is a vertin6s+x:lsu e ()ngsv)k, o0qqscal line, the object is eqs(v )lg qso+,u6kx) snns0:

  If the velocity versus time graph of an object is a horizontal line, thet8jgmbry q5 ov:7 ;bm7 object isb;vm5 tb m:y78qrgo7j

  If the velocity versus time graph of an object is a straig ;96rv9 22; xntjqtrmzvx)vx xht line making an angle of 30 degrees w;v29xr9 qj62xnv t )xtvm ;zxrith the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both thqd+esqq93ww:k *t27g wn bvr3e distance traveled and the m*2nkt9qrb 3qg w:wd7e+q 3s vwagnitude of the displacement vector.

  A boat can move at 30 km/h i b9xf)f-, rqo/f5pd jfn still water. How long will it take to move 12 km upstream in a /or f-qbjpf) 5x,9 dffriver flowing 6.0 km/h?

  55 mi/h is how many m/ wt dsek(j4h78ne4x 8;kyj z;ks? (1 mi = 1609 m)

  What must be your average speed in owx5o3)s,z coi) 7fqzyrder to travel 350 km in 5.15 h?

  A runner ran the marathon (ap2-s5uh.:5vh ;* err) wjbcrusl/e kfnproximately 42.0 km) in 2 hours and 57 min. What is the average spee5:ejk.hshebu- 5nrvsfl ;2/ wrc *ru)d of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to trave0 css:p m me0..rd1u m. :1y.n7tabjmxay: chjl 400 km?

  A ly (light year) is the distance that light travels in one year. The :z 9)vle o. 9fxhtg0qyq0 cz6wspeed of light itv6)0gy.qx z0c h w99leq:zof 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 straight road and you look to the side for 4.)edvhkfdwp1s ( /,5u r0 s, how far do you travel during t erfdv5kp,w /hd1 ()suhis inattentive period?

  If you run a complete loop around an outdoor track (400 m), in pxaxt */g5h li1tl: b)100 s, your average velocitph ilg) t*:abtl x1x5/y is

  A polar bear starts at the North Pole. It travels 1. f wlop6p.,i*o0 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 speed6 iolpw,pf.*o ?

  A polar bear starts at(6n2stnewbz wesgqt13 ;,) :advflj + the 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 trip takes 45 min. What was the bear's average velocitz,s1jebavt(es wnt2ql: 6fdw3g+); n y?

  You are driving home oiw) ,z o9lw52w1x,lt yw4fhj;x 4pnr an a weekend from school at 55 mi/h for 110 miles. It then starts to snow and you j; x2oli5za h19rpwt wl,,f)ywn4wx 4slow 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 km5pg:6l 5zwnzv at 100 km/h. What is the average speed of the motorist for this trip?v:g5z pn5 zw6l

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at /a4nyovg b/i /imz( g49gyi2g100 km/h. What is her average speed for the yg4 4vi/ggoma2(yi9 gz bin//trip?

  An airplane travels at 300 mi/i clp zl 9;/z2-ppbt bcgs2/*eh south for 2.00 h and then at 250 mi/h north for 750e*clz2ip /zbgpt2 l 9/s;p- cb miles. What is the average speed for the trip?

  In a 400-m relay race the ak6qw3guvq6b; nchorman (the person who runs the last 100 m) for team A can run 100 m in 9.8 s. His rival, the anchquqwv ;bkg63 6orman 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 the team A runner not lose the race?

  A car decelerates uniformly and comes to a st1 he3ly2yi4 (nxhfy+ qw 1ec*gop after 13 s. The car's average velocity during deceleration was 47 km/h. What 42lh*yc whq y(n +yex11egif 3was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average7dtgr6a:db f1qe r1 1r rate of 11tfrgrqdd e 1a:r7 b6$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the r72 j9z91g ze cee*mouhate 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 accele3g1e bedj1ja )rates 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 16.vtapc/ bzy for 10 s. It then speeds up with a constant acceleration 61cv/tzybap. 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 6.3 m/s experiences a constant accezzf uli+g2 6;a+7 g4 ubwp)ywjleration of ;)gpfb 762a g z 4zuiwju+y+lw$2.5 \; m/s^2$. What is the cart's displacement during the first 8.4 s of its motion?

  A bullet moving horizontallykvwqq * **gkcv +jz2v. to the right (+x direction) with a speed of 427 m/s strikes a sandbag and penetrates a distance of 57.46 cm. What is the a+kv*.g qcw2 *zvkqvj*verage acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraftm. 9ms) gbgbh 20vonyhj0p ;e, carrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2bohpmns9 m,j2;b0 g.0)v eyh g.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest movey2i n/jsex k;bq.uo89s 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 distancs cvx8q)i*9 klj;l8 cce of 200 m. What is its average acceleratiosqj8;cil *9ckv cxl)8n?

  An object starts from rest and undergoes uniform acca* ce2u5 ph8(uc ybuz-eleration. During the first second it travels 1.7 m. How far will it travel*zbu 2eu- 5hpyca8c( u during the third second?

  An object is moving in a straight line with constant acceleration. Initiallqu82k is8h.(khj/ll c 9us ,oty it is traveling at 16 m/s. Three seconds later ilj,/ch tukh8oslq9(k s8i2.ut is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates uniformk0wfi7r, x o:m,ij2fng2w 1v xly 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 dryh98a v +*g4zikax/qce 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 gie xe;2 tq) ,,sy:ifqhreen, a car that has been waiting at the intersection starts ahead with a constant acceleration ofs y:) f;,qhxe,2 iqtie $2.00 \; m/s^2$. 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 plc0:d4r0/jcrhw2 owpfp t -(ebanet X where the acceleratio 0(ep-c0t2prwhof cdj4b: w/rn 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 surface of plvo /uago zfo.e4b/8 7yanet X where the acceleration due to gravitz. ao 48/uog7 fevbo/yy 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 sjo 8hr f a(1dpe.p)cz3peed of 15 m/s on the surface of planet X where the acceleration duo.(h3fze)d pcr8jp1ae 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 a4/dz wrzk4 9hj7looa6dy 2q*i6 z,cge speed of 14 m/s on the surface of planet X where the acceleration due to gravizz6*2d o a g i 4zcky64/w7o,jr9eldhqty 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. loz:;rs 7w-4ofah : hs If your friend holds a ruler between your fingers and releases it without warning, how far can yolsz7s4ohr:- ow:f ah; u expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m:(qqa; 8c4vpiw n;hfp/s. What is its velocity after 3.0c f;h48wq:aq ;n vp(pi0 s?

  A bullet shot straight up returns to its starting point in 10 sg0rk dvhewp+b,32 xh6 . What is the initi+b0krxgd v6hh,2p ew 3al speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long doesn6gyhvyues+k : 03b3d it take to return to its starting +:s yh3gb6eknuyv03d point?

  A ball is thrown downward from the top of a buil gt pkd6e64*x3z ye(uqding with an initial speed of 29 m/s. It strikes the ground after 3.9 s. How high is th kez4 ue66x*q p(ytg3de building?

  A ball is thrown straight up wih-x,++7jfiman. co ,,hrksxnth a speed of 30 m/s. (only fill in numerical value ,+x a,c,7xoh.sm n+hkfinr-j 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 the air with a speed of 1nbfgdv2l/o fi -a/ .covmjc56 pix1)47.8 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 7 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 7.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity acxe)azv/ :fj1pw+v zp /x5o/xt t = 1.0 s?

  In Fig. below, what is the velocity at z-ppw.9-a,(r4rivea qd ozwx2(ce;t t = 2.5 s?

  In Fig. below, what j b)5ctejsf6s g54h:kis the velocity at t = 4.0 s?

  In Fig. below, what is the velocity at t = 5.5 hh 6/m/dx)tzm phm) 5ps?

  In Fig. below, what is the average velocity fro 6+ nnqilms15ra 0z4 tusm-ea(m 0 to 4.0 s?

  In Fig. below, what is the avef jpjt89- x487xnr5aysj8ilj rage velocity from 0 to 6.0 s?

  In Fig. below, what is doqix4xi2vls 2- 7io;the acceleration at 1.0 s?

  In Fig. below, what is the acceler01clw4mpab8 l ,rsr; sation at 3.0 s?

  In Fig. below, what 7 vs+kbzlp92fqhfavg/c 433b is the average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 4;r u3ybe0lxjb (h.pm8.0 s?

  In Fig. below, what is ttrse a (yij2p2pt p6 h,a*;-vtnc9w 9she displacement from 0 to 8.0 s?

Does a car speedometer measure secfftd5hiuy7c ttwm(c053/ 3 peed, velocity? {speed|velocity}

  An object can have a varying speed if its veloc9a75 vea9px rwity is constant.

  The velocity of an object can be negative when its acceleration is positive.y g(lawa c/+lid-b4p 0c.v l/ranu7 )r

  If one object has a greater speed than a se 6)00 01iyhrbzml xpmicond object, the first must have a greater accelerati10l)xm0ip0 bm ryhiz6on.

  Two cars emerge side by side from a tunnel. Car A is zx0 .h2y ghr2zuqv z5u*vs1b 7traveling 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 increas1 kt)vl apcf3docl86yub;jy y5 4ux.7ing in speed as its acceleration decreases.

  A baseball player hits a /7va 1yl(c j29(i;v-mmobh vh ojvv;hfoul ball straight up into the air. It leaves the bat with a speed o/l 1 ((-hbmj 2hchvma7j9oovi;vv vy;f $120 \; km/h$. 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 fw0a1yevq 6-a its acceleration, how dow1v afe-ay 06qes it change if air friction is ignored?

  As a freely falling objer)hx2 gpc* )gznq)6cnct speeds up, what is happening to its acceleration, how does it change if air fricthc xz)g *rng qnp)c2)6ion CAN NOT be ignored?

  An object that is thrown vertically upward will return to its original pk1ezc(lpv+k 5ffd 0f/osition with the same sp01+f elzc/ vkd f(fk5peed 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 pg;eg n q(9g7dvelocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at the same time.cmt2 ut/*x; bsb -hr9o+fk6w i

  An elevator moving from the secondnbseb9jg:1 :w floor to the fifth floor making no stops along thgeb1 s 9b:nwj:e way has zero acceleration all the time.

  A rolling ball movesk ,bwl(yao0j1 p r2+b 6iipdk5*pkx4d from $x_1=2.9 \mathrm{~cm}$ to $x_2=-6.6 \mathrm{~cm}$ during the time from $t_1=1.6 \mathrm{~s}$ to $t_2=5.7 \mathrm{~s}$. 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 $x_1=2.6 \mathrm{~cm}$ and at $t_2=3.6 \mathrm{~s}$ is at $x_2=7.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight completsofxai *4hiysyf 83ipu1sh58h-n5,a sot6w6 e laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 6.7 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 ln omm: eu*j u1dp3j8(vine, moving 113 m away in 9.3 s. It then turnsneouuv8 m13( dmpj:j* abruptly and gallops halfway back in 4.7 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 froml,8hi tq4,cvm; yffx3 $12 \; m/s$ to $24 \; m/s$ in 4.9 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+z ,mbgg/u gq0 $20 \; m/s$ to rest in a distance of 70 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach 3)ofr ri5d(dv a speed of $26 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.7 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can bursk(x1qpsp da vfc(.- ,a;d7fdo t out of the blocks to essentially top speed abou.pqc7; d-x(pf v 1,of dadask(t $11.0 \; m/s$ in the first 13.6 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 -aq5;dh o7yq. e: fefl;-lzn aof $17 \; m/s$ to rest in 5.48 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leav pwzz+ jzke957ks, 0 ugwpt sx0e82*fzes skid marks 92 m long on the highway. Assuming a deceleratwsz8kg+7 z,jtz*p ue0 wx2ezks0 95fp ion of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goifki d;ujkxuw7 (od35;ng $25 \; m/s$ 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. A+g dp(nl,g wi*b*p7 ucfter exactly 27.0 midg*i+p7l,cb(g*u wp nn, there are still 1100 m to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$