Suppose that an object travels from ob 3yazhme/(;1ce l5rone point in space to another. Make a comparison between the displacement and the dista5mych(r1 l zbea/eo ;3nce traveled.

  When is the average velocity of an object equal to the instantaneous veloc1vhybg (sw(f5ity?

  A new car manufacturer krgv)+ 9tgugr-v/ ; fjadvertises that their car can go "from zero to sixty in 8/grk+ggv ; -jtvu 9)fr s". This is a description of

  An object moving in the +x axis experiences l,w2w oe gm c(+u-j-hkan acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveljhpqrp/0vb x t8./ojp1f 6l ,eing to the East (+x direction) begins to slow down as it approaches a traffic lightxpt bohf/6 l .0qjr8/p1 epj,v. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x directx2 m8/nm.:o quk 1dz-qgw;mbf-d .yhha r 1b4rion) begins to slow down as it approaches a traffic light. Make a statement concernbn .od g y81aqm f--mhm;1 ruq.dz2/b:4wxkhring its acceleration.

  Suppose that an object is7sp (h3ic d 5f6bhone; moving with a constant velocity. Make a statement concerning fc b( hdni p3567s;heoits acceleration.

  If the velocity of an o;rc5lclc0sz *p 9w .s )v 9(iukol/sjsbject is zero, does it mean that the acceleration is zero? Support your answer with an exampl rupsswoz/ ll5)* v09 (cscsk;j9li c.e.

  Can an object's velocity change direction when its acc x.wij8,h0wmf eleration is constant? Support fwhj0w .,mxi8your answer with an example.

  Suppose that an object is moving with constant alvl a0.5:zbp7dmx auox l2h*hp9qo6y( go ,5 bcceleration. Make a statement concerning its motion with respecyq5a x2*,5:og bb0oo.dpuxza hl7mlph 69( lvt to time.

  Can an object have increasing spf;-u xp q4 bfv0;/7sx;cvpw iceed while its acceleration is decreasing? Support your answe/iuppwx;7f 4b vc;xvq-fcs; 0r with an example.

  Suppose a can, after an initial k;8tqt kpwt8 +eick, moves up along a smooth hill of ice. Make a statement con ktwp t8t+8q;ecerning its acceleration.

  Under what condition is average velocity equal t/m0)0+6 mbvhkf0 xvimybwj s:o the average of the object's initial and final velocitf:s0v0 m6hi bmbm+y)0xv/wkj y?

  Objects A and B both skuiq(gp d9i.zz(v68 yh /4dh utart at rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final speed of.uz9 uzhqhk(p 6i8 4dd(yvgi / object A compared to that of object B?

  Objects A and B both start from rest. They,6,id :itm6 1prnpr vc-dmj+j 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 t1:cvp-mr+id 6t ,dp,jinr mj6hat of object B?

  When an object is released from rest and falla1d4 tpt;-u ,qd oft.r4c1hdis in the absence of friction, which of the following is true concerning it4 c. d1tfu;oih,t tr qdd14pa-s motion?

  When an object is released from rest and falls in the ab n0mqwu8y0o s7dabmp 6o x(j):sence of friction, which of the following is true concerniny 6px0qao :u0m(wb)od7msn 8 jg its motion?

  Suppose a ball is thrown straight up. Make a stateme4mp4: ,-;mbao9 x+pi yzi: nbibuo3xjnt about the velocity and the acceleration wheno;izp-pxb3i: m44o axuynb9,b: i+ jm the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before ioq1)mc 4vb27jrb3wo5i0hn3h u(q n s qt reaches its highest o31 v q5n 7m4(2wouihbhj)c30sbq qrn point?

  Suppose a ball is thrown straight u,n) yn/ nppqa*p, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velo,nnp)/* nq yapcity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then fal54alqi-e 0gs pls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming dae-s5 lqg 4pi0own.

  Suppose a ball is thrown downward in the absence of air resistance. Make a st-wsiq wo+qs, 3atem+ wsoqiws,3q-ent concerning its acceleration.

  Suppose a skydiver jumps from a hig)0sc55*krr 5x xsmc8)f8 kj we, yumjhh-flying plane. What is her acceleration when she )j0kmckxumfs 8j5*wreh y 5x5,rs)8 c she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. jhvf+-je.ov1 38c nfx An identical second ball is thrown upward with a speed 2v (twice as fast). What is thj-hfxfonj v81ce3.v +e 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. pl7g v)qn s2xotqut61u 8 7p0y )(yixnOne second later, ball B is dropped from the same building. As time progrt()yxn vpp6ny2u qls877 t) x0qui 1goesses, the distance between them

  Ball A is dropped from the top of a building. One second later, ball B *9szj 6 )u;ebt ot+1ex8b ryad+;zl qyis dropper++eot)xyj et 8*dsq;b a19 luyz;zb 6d from the same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, andb5yu foj 3 suo 5w)pdo,o7vjn6o)1,zo+1drwj the other is thrown down, both with the same initial speed. What are their speeds when5o o,u3+7,1 ovb)oj6 oyj)d spj1fuwzw5rdon they hit the street?

  A brick is dropped from the top of a building. A second brick isl55nd kot0.uk thrown straight down from the same building. They are released at k dun 5k5olt.0the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the :h(cxdlol+6 w+x axis. The position verswl(h l+xo6cd:us time graph of this object is

  An object is moving with constant non-zero acceleraz wc2r)urjkxf3n ocyv c,0k8/+ :ab-ztion in the +x axis. The position versus time graph of this obj nv,ca2yfjz) zrrbkc08 /o:-3wc +xu kect is

  An object is moving wits(p*akc i4u3qh constant non-zero velocity in the +x axis. The velocity veq(*ikucpa 3s 4rsus time graph of this object is

  An object is moving with constant non-zero a72 lg/icf7 5go,rnh*g .ytgdu6 z w5xdcceleration in the +x axis. The velocity versus time graph of t 65lg5gdug*, 7 nc7d.fr2zhotxy/w i ghis object is

  The slope of a position versd27ti/pq9;t wc;npg; acy sf0 us time graph gives

  The slope of a velocityi f887+8rc syykqfy9 k2q lov0 versus time graph gives

  The area under a curve in an acceleration vj8 xg snlu(,j r6pbvng7+m7n0ersus time graph gives

  The area under a curve in a velocity ve;q, ,e*pdrvz srsus time graph gives

  If the position versus time graph of anx99llnqf c0 8hyf6 qr: object is a horizontal line, the object 8qlqhcnf rl96:0x 9fyis

  If the position versu,sxy 8tb s tr/7 o5eja*;kwp8ls time graph of an object is a vertical line, the object iso e p/trw,*kjlsa8tb x;5ys78

  If the velocity versus time graph of an object/+jhj wr 0 h/9us9ixxw is a horizontal line, the object /jw9huw +0isjh x/xr 9is

  If the velocity versus time graph of an object is a straightvacbj,y) a6wd ff8*5e e fb,/b line making an angla)j6 ,b/fcbvy b8faw,5 efed*e of 30 degrees with the time axis, the object is

  An object moves 15.0 m north -wjj kzq6/l(4.i drv.gka : kwand then 11.0 m south. Find both the distance traveled and the m-v.4/wzgkw i.k jdl:( jq6r kaagnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it gjfj5 .2b k6mwrqzm6: take to move 12 km upstream in a6r2z6.qjwj5kb :mfgm river flowing 6.0 km/h?

  55 mi/h is how many m/s? f6+s 39iprwgk 7q4a pg(1 mi = 1609 m)

  What must be your average speed in order to travel 350 km ixpn0;e wz),tlw 5deep b : ei65y,hwz8n 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2r mb/-o 4iux2k hours and 57 min. What isb4/-ko m2uirx the average speed of the runner in m/s?

  A car travels 90 km/h. How long dmw j*ccv/p6w mrf2 -e/oes it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one year.tice e)l;b1 8g The speed of light igl t8;e1ec)i bs $3.00 \times 10^8 \; m/s$. 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 straig)pzprj6z+pn p5p r (g-ht road and you look to the side for 4.0 s, how far do you trp)pnjzz +rg(p- p5pr6 avel during this inattentive period?

  If you run a complete loop around an outdoor tracw8f+ yciu4)4qo ud(uok (400 m), in 100 s, your averag+4o) 4du(f o icu8uwyqe velocity is

  A polar bear starts at the Norta0 n+o k-p,hjch 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 pnkh-oj+,0a ctakes 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 .+kc fhx-teg ,km south, then 1.0 km east, then 1.0 km north, then 1ec, -+xk tf.hg.0 km west to return to its starting point. This trip 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 mileag q t1 vgt:cv)7t;mi/s. It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How fgt; ) gti 7ac1tqvvm:/ar is your hometown from school?

  A motorist travels 160 km at 80 km/qtrlk+zf:4if;c7k j 2h and 160 km at 100 km/h. What is the average speed jl72fftz;kkc i4+:rq of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 10,/i9ytdoj2wa p+(e sr0 km/h. What is her average speed t e+9d yps/,(ir2ojwa for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then jk9t7cch hf,3/)mjypat 250 mi/h north for 750 miles. What is the a7pmk y f3, jjct)h9/chverage speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for tejgdnrd s;,29 8x- )ptv6le,hbf:thg xam 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 the team A runn)dtb, e xf ,;lrv2 d:6p8x9-jhgsnhtger not lose the race?

  A car decelerates uniformly and comes to a sto87k tzx +3r f9:taafikt+ dz;tp after 12 s. The car's average velocity durint tax+ i8 kdktf r:7z+atfz;93g deceleration was 53 km/h. What was the car's deceleration while slowing down?

  An airplane increases itk1iz m(3nbhv02 ;forgpc xsegd+7(/ ys speed from 100 m/s to 160 m/s, at the average rate of gmv3 o ;sg/x1+fp(dbknz2( h70icr ey$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acceleratesny*9lm( o*q;yj+ wk-bkf3 xv q 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 o2wt wv776nub2 vi o;saccelerates 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 in)kv+vm nl)zxz87*o for 10 s. It then speeds up with a constant acceleration)7vzz8*x )+vmnlik on 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 2.7 m/s experiences a constant accelerationl cljlg-f)0bn/q49c x+;a.ly - z bdnk o c.gfy- )jn+dl ;nqa9bb-l xc0lzlk/4f $4.6 \; m/s^2$. What is the cart's displacement during the first 9.8 s of its motion?

  A bullet moving horizontally t58 jrj n 1z5euda5i3flo the right (+x direction) with a speed of 308 m/s strikes a sandbag and penetraf5eujjd58 3iznalr 15tes a distance of 48.71 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aisu;ap+v5wd1u i k i5l-rcraft carrier. It reaches au 1v+a5likpi;-wu d5 s 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 rest moves with constant ac/d r(;pplns k )/t*jfoceleration 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 its averagefvdk/ s*h v4e: accevfehdv*4/k :sleration?

  An object starts from rest and undecmx,d p*t25mn,/pp yp rgoes uniform acceleration. During the first second it tra5,/xtnmdp2, pcp py*m vels 4.6 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Inite.1c g w;:)7p yj us)vzird;bzially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?):rzsvd;c i g)1. 7y;bjuepwz

  A car starts from rest 3x:e ap;xr)5a4u /ni ep4jph 4cxvd 1eand 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 dryrxo6 jlala2 +9 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 green, a car thaf0 xqv7ffuqt)ll*, q 1u2-sadt has been waiting at the intersection star,fv7u-2d fl q alfqsqu1)tx* 0ts 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 of 12 -uvq .j3g+o rttk -/gom/s on the surface of planet X where the acceleration tk . tvr ug3qo+--j/godue 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 planem mtfxtkt7b :ldftq905 m4 n--t X where - m0btt tqm-xkfd9:4 ntf7l5m the 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 surface of ,bqfu0e8o(a q7xl a 8yg)t )r x2jwhz3evy 5y9planet X where the acceleration due to gravity g 0o5 q3j29xx y)8bq8a vuz(rhe)le,w7ayt fy 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 planet0o*6;dwbu5 sh gc p2nsc *l;cwc*rv(f X where the acceleration due to gravity;gcv25 hpbncw*;c* o uf*w6lss0rdc( 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 holds a ruleb-+xrgs ye4 y.r between your fingers and releases it witsy4.xy+ e g-rbhout 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. Wha-g xz;w0+cnfzsy no49t is its velocity after 3.00 s-wfo+zgx49cnzn 0;ys ?

  A bullet shot straight up returns to its starting point in 17 s. What is the in4gu jf e));tyxitial speed of the bulf4x ;eug)tyj) let?

  A ball is thrown straight up with a speedv +dnq7w* e8y h;unjkpbu,jm):,njj2 of 36.0 m/s. How long does it take to return to its starting poi;e w2nk:uv,juq78+y)m npj*nb j, hjdnt?

  A ball is thrown downward from(h5fyce+ el4m*w cmule 9g7f m s/-;zn the top of a building with an initial speed of 15 m/s. It strikes the ground after 5.4 s. Hle wc7msmu hz(gfc4nee+;ml9* f/y- 5 ow high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numericalipa/5kye07habur) i- value i/)y-aibe05rka7h up 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 t 9 2sudwta y72o2rlhhi;3r 9vche air with a speed of 37.1 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 13 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 13.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1.0 s7gzzied72u8 gpq* fpm3+; o cy?

  In Fig. below, what is the velocdymw) -fr 8 g8zc5bd7wm,dx16y4lbdm1 v6dk uity at t = 2.5 s?

  In Fig. below, what is the vesaj/ em ax5ats0cn 0)op 8cj9 02hp:lzlocity at t = 4.0 s?

  In Fig. below, what is the veloxxy0 env y* 9nsfz13t+city at t = 5.5 s?

  In Fig. below, what is the average velocity from 0bof./y el0tc:s 4dm :q to 4.0 s?

  In Fig. below, what is t63:dp- newplfhe average velocity from 0 to 6.0 s?

  In Fig. below, what is the accelera)*bafak7xts) v2wo gk5nn. *jtion at 1.0 s?

  In Fig. below, what is the accelerationc8 ( xre -):jr-mmqz awn8o9.hfjy;o v at 3.0 s?

  In Fig. below, what is the average acceleration from 0 to 5kzxm2p3+fxr so6o s0; .0 s?

  In Fig. below, what is the average acceleration from 0 /deurh.pvp.a 8)lus* tub w4(6) pvik to 8.0 s?

  In Fig. below, what is the 3bqjhn-9e cp 6v;)bnev k. 6ws9bup10 m vlk.xdisplacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|velocity}rc, 2xq1a,dch*e/yu p

  An object can have a varr swbicmuwf4/tho4o uz+u23 .9 .vk,cying speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is pomo8c:e45 o:/:d,mjmhdu yui csitive.

  If one object has a greater speed than a second object, the firstsl-4u/bvh ,:pitk,/ evuuv.tf+a ap8 must have a great8 u+: tilv,puf- h/ptab/us ,4.ave kver acceleration.

  Two cars emerge side by side from a tunnel. Car A is travel2n7bf1j)m ct/ i5yppming 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 increasip(a y utu7j(i9ng in speed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air. It leaves the ba3 h.8 av:+v kkwr1ieiat with a spewk.i+e 8ahikav:r13ved 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 objecton-8ru p3xut0 speeds up, what is happening to its acceleration, how does it change if air friction is rou3n0u pt-x8ignored?

  As a freely falling o y1r62q f9foug4egrhph:7 l o+bject speeds up, what is happening to its acceleration, how does it change if air friction C lor rqf2opu61h 9 7hggyf4:e+AN NOT be ignored?

  An object that is thrown vertically upward will return to its original position sw)3ka 9-nud nw5vsfvg 3.ck/with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be alter-) vww.kcn vfgs9du5n/ sk33a ed?

  An object can have z gi jr+94mn;nb qgmw8jn),r32 bljq1gero velocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero accelredpz 9 lw))o+eration at the same time.

  An elevator moving fralz+s f 45koexm.q5*y om the second floor to the fifth floor making no stops along the way has zero acceleratio xl zqe5.*kom a4s+5fyn all the time.

  A rolling ball moves j5 zu9(r jmaf1from $x_1=3.2 \mathrm{~cm}$ to $x_2=-5.9 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ 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 $t_1=-4.8 \mathrm{~s}$ is at $x_1=2.9 \mathrm{~cm}$ and at $t_2=3.6 \mathrm{~s}$ is at $x_2=8.4 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps arourrhwuuk) -ifi i )51)p 9f/glind a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 8.6 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its trai brrcu(jp:dza( :kqa gr ..g**ner in a straight line, moving 92 m away in 8.2 s. It then turns abruptly and gallops h:*c. :p( drujbarkag. r*z( qgalfway 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 frioy tm .ik+zi ly/ck,s+9 o/ju.9db. ek nf,o:om $11 \; m/s$ to $24 \; m/s$ 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 from fwe cb0sy.rr;)oo 9.m$16 \; m/s$ to rest in a distance of 70 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speedsfwfb .e-ikj / 6b60uy of $25 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.4 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocksh; shws /5zeh 1r:d,7s (*qbug+fc kbs to essentially top speed about *; 1h s5+gq r,s7s(zu/shbhwdbe : cfk$11.1 \; m/s$ in the first 10.8 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 a0x*x.ybt +9uk3 pvgxg speed of $21 \; m/s$ to rest in 4.60 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 hi amp8sl8.sepi77c s y5ghway. Assuming a deceleration of csa y ssp.e88mp577li $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truc hf2vw,au(i3xk 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).    $m$

  A runner hopes to complete the 10,000-m run in lessjp-vhhrjh q ; j6f+6v :glnr.) than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must then accelerpvh v6gj-qf+jhn:j6 ;hr. r l)ate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$