Suppose that an object travels from one point in space to another. Ma :fw -og2j) ojr9uwwi-ke a comparison betweeno9) u2ww :gjf i-o-jwr the displacement and the distance traveled.

  When is the average velocity of an object equal to2x i+ afm,q+l9/nnaeu the instantaneous velocity?

  A new car manufacturer advertises p:ma9 :cq31j*v mpko hthat their car can go "from zero to sixty in 8 s". This is a descri*kvp mqpm9o3ha cj:1 :ption of

  An object moving in the +x axis experiences an acceleration of uma7. wuk.w*m $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x dhbplprf+q :;oky c; 1:go,yu z gw4s15irection) begins to slow down as it approaches a traffic lig15wr c4q;f+:pplbok,o1h g uszg y :y;ht. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) 0*hr+dm:gj -ep/ +x)jeih ddsbegins to slow down as it approaches xi h:hd/mep-je*g 0sr) +d+d ja traffic light. Make a statement concerning its acceleration.

  Suppose that an object3jha8w0q+nc ay.d5d nj9f x7n is moving with a constant velocity. Make a statement concerning its acceleration.5fjjnahd03 qn cdx97+. an8 yw

  If the velocity of an object is zero, does it mean that the acceler*a8uvett -b h/l-n1n1k jn;akation is zero? Support your answer * 1;n/jv1l aenatbhun t-8 k-kwith an example.

  Can an object's velocity change directio ; mcuglti1v6 9wwg/n(n when its acceleration is constant? Support y/(it6m;g wg c9ulw nv1our answer with an example.

  Suppose that an object ca4hilujt).v9bnlbay.ns 86 mf5 1)tis moving with constant acceleration. Make a statement concerning its motioj5 16ulb)yvha n8 .)l aficnb49ttm .sn with respect to time.

  Can an object have increasing speed while its ( 071uip wxq 6ubz4avorv :p8dacceleration is decreasing? Support your answer with an 4oqzuv p71a(wi:d xv0bu86rp example.

  Suppose a can, after an initial kick, moves up along a sy ps5nx4l)/3jysxo mu6e5 i9m1bgw a/mooth hill of ice. Make a statement concerning its accelerationweb3/u 4xly9 /6m1aj ys5)pmsnxg 5io .

  Under what condition is average velocd* t p;xc,:pwdps21c0 a jdnk0ity equal to the average of the object's initial and final velocity? d;p dw,c sp00xa:*1p2dtcknj

  Objects A and B both start at rest. They both accelerate at the same rate. :3 xs4k:ioiqyjrvf(zl q i;61However, object A accelerates for twice:i14kio sfv;3q: xl i 6zyqj(r 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 f)v *sbgmva-7kytp /;o rom rest. They both accelerate at the same rate. However, object A accelerates for twice the time as7o;t-sg v/apyk)mb* v object B. What is the distance traveled by object A compared to that of object B?

  When an object is released from rest and fallr89 +ohjhrc, hoa9l/ ls in the absence of friction, which of the following ija h+r8 oc9 9ll,rhoh/s true concerning its motion?

  When an object is released from rest and falls in the absence of friction, whichm*l* ubt9d4 cp2gw2w p of the following is true concerning i2w *m24 dpp9 tulwcg*bts motion?

  Suppose a ball is thrown straight up.nhss s 0cj*h4x6+p8v j Make a statement about the velocity and the acceler 8*hjh40v+ps6csj sx nation when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before it rs2 f+8 eb1rfha 1y*h:r:r xhonb)(vrreaches its highes x(an *fob+r) r:fhr8hvb h 2r1:rey1st point?

  Suppose a ball is thrownr ya2xz qdra(n-68:n b straight 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 isanqnrb 2 z: dxa-6y8(r going up.

  A ball is thrown straight up, reachesa c2;)1i0i ye*sl* sgsxd au,l a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as te*01xu agil;ydai) cl,s2 ss*he ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistanc ls2kywmr 1 fa2c4-so1e. Make a statement concerning its accele1mco1 2yskf2lr -a 4swration.

  Suppose a skydiver jumps from a high-flying plane. What is hhs0c5oh ys4d z6+ uy.ger acceleration when she she reaches terminaldu4o5yshzs hg 6y0+ c. velocity?

  A ball is thrown vertically upward with a speed v. .dks 1ztan:6 b ojbh65 An identical second ball 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 d1 o:5 6kazsbhbn6. jtdoes the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, ball Bsjc37fz a6i/o w o3ex7 is dropped from the same building. As time progresses, tzxico36we 3 oaj/f77she distance between them

  Ball A is dropped from the top of a building. One second later, bq ivh,+xbzmhcx:5-ip ai j0./all B is dropped from the s0-xm/ji:hi b5+ .phaczxvq,iame building. As time progresses, the difference in their speeds

  Two objects are thrown from the to ez jhzlvre57 srk/3,)p of a tall building. One is thrown up, and th 5r/s k3e,ev)hzzr7l je other is thrown 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. k*aj p 62gkclxy;frb(h5q; e4A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Ckgla52fk;4*bcy;qj px 6(h e rompare the accelerations of the two bricks.

  An object is moving with constant non-zero*fsp4i k zbd:9 velocity in the +x axis. The position versus time graph of this ob:zp*bdi 9kfs 4ject is

  An object is moving with constant non-zero acceleration in the +x *) hfolxawxw oex.)x2 )zrd4-axis. The position ve*wa)rxxxzh.w dx24eo -)o)flrsus time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. The velocixp6*h( xgwk3rkt .hes4 (o/ddty versus time grap. e 4x3(kk6sxdh tg(howrp*/dh of this object is

  An object is moving with constant non-zero acceleration in the +x axis. The 5h * f:m jje1hyfxd,i(velocity f:1h*hjdime ,x(fyj5 versus time graph of this object is

  The slope of a position versus tipqd r49u1bvmhgwix qm8021o 5me graph gives

  The slope of a velocityw p3wsn5r(b x1 versus time graph gives

  The area under a curve in an,n+ /digz7wwo acceleration versus time graph gives

  The area under a curve in a velocity versus :wyve d 1-gkul -*np7utime graph gives

  If the position versus time gra(/yuu04 q 5ox5zq, f-zpsd bacph of an object is a horizontal line, the object ixyqzp q z(o-fdu,5cb/4 asu 05s

  If the position versus time graph of an object is a vertica.cwi4an z m n;jdtnq/ 4/+*c2umro 6cql line, the object isjnn rz2cq; cdmw com+q n*/.u4/it64 a

  If the velocity versus time graph of an object is a horigk4w 3( udj+ lcg iw)zkk,;/b ea4/iezzontal line, the object is k );d//ek 4i clua+gwk 3w,(ezjgiz4b

  If the velocity versus time graph of an object is a straight l lmm*vq(d ;wlc mgo 1 xr,+9s8xd)g7i*fmzmq2ine making an angle of 30 degrees with )w l,lqi;f s *28(9mdrvdx*7zg1+mmogm x q mcthe time axis, the object is

  An object moves 15.0 m north and et14g+a)b77 ) o o)nduweg zmithen 11.0 m south. Find both the distance traveled and t )am174g)gweo b7 ienu)t+dozhe magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it take to move 12e/ fzs)*6v wvs km upstream in a river flowing sz6s /vw ve*)f6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 16 68rq xlp*w5jk09 m)

  What must be your average spee ejqa tlkc9 amm9l*0723rys8fd in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 h-m; vsg tkfp4;ours and 57 min. What is the average speed of the runner in m/sp s;m;-fkvg4t?

  A car travels 90 km/h. How long dou7lf )lwr)9qd es it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one year. The srdi 8bi6g.oy9lsw)c co6 z,.i peed of light z)6,lwr 68 io9.bi. sycg oicdis $3.00 \times 10^8 \; m/s$. 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 lookfp 0 4i0zppvw)( hhmu; to the side for 4.0 s, how far do you travel during this inattentive p;4zphm hw( vp0) ifup0eriod?

  If you run a complete loop around an outdoor track (400fmsmm()g,7 w3d j9n4y e5t tje m), in 100 s, your average 5j7s(t jtm3medfw m),e49gy nvelocity is

  A polar bear starts at the North Pole. It travels 1.0 d 0ahdn73u+nac 6yzmp.ev + ,kkm south, then 1.0 km east, then 1.0 km nzcv+aun6k. +dmye a3hp7,0ndorth, 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, then 1.0 km eaxl/m2zn l+ 5onst, then 1.0 km north, then 1.0 km west to return to nlnlz2 ox/5+mits 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 miles. It th4f rh-hp79q fxen starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. rf4qph-h 79xf How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h.ip5vx/oqg cjk n/2 .m, What is the average speed of the moto,2on/.5p/q jcigvmk x rist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is hermeuz)j (o jep veyq0s :.u.)6uys01p m averag0yvmpque (ezuj y1s oj)..s)0 6uep:me speed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then i a1eczxcx-9 kz e)aq+i 3e70kat 250 mi/h north for 750 mile ai)0e+ q zcx3a1e-xiczkk97es. What is the average speed for the trip?

  In a 400-m relay race g 9bqb ul6d mhm 6qkqr;.uua9q5l9s .0the anchorman (the person 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 is9u mmd qkq. s9qh6a 9g.5b;bllr6q0uu 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 comeoif9 lv+2gjn *s to a stop after 9 s. The car's average velocity during deceleration was 49 km/h. W9g2 jlf*vnio +hat was the car's deceleration while slowing down?

  An airplane increases its speed from 14xbs,r9v8 olx9cd jurp n2:3j8gq+ts00 m/s to 160 m/s, at the average rate of svcp+4u8 9 r odnj 9qs8x,:g3btjrxl2$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelknsarm.i/ p;,(k/ )l6jh 6hnkqyisx ;erates 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 accelerates at *tu gonidti-s:5 0v1lx kfh, e(b.v8w$4.0 \; m/s^2$ 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 xz2l:qc6g 0 id10 s. It then speeds up with a constant acceleration o2xizq g 0dl6c: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 4.8 m/s experiences a constant accel m+ )*ijnljjstf)1z4f eration omsf tnf+jl*4 )1 i)jjzf $2.0 \; m/s^2$. What is the cart's displacement during the first 4.2 s of its motion?

  A bullet moving horizontams 9s5,x z6ozglly to the right (+x direction) with a speed of 588 m/s strikes a sandbag and penetrates a distance of 80.99zx,s6o59gm zs 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 carrie mzxl;rvtdqw 0oil 645- lg3h(r. It reaches a speed of;3r0 4zvtilhwqlldom g - 5(x6 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 mess. 6 o/b(w7kas jx/doves 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 distance of 200 m. What is sdu q5dp w5j,x/zlhuu53+a; nits average acceleuq 3;u+uh /pxn5alzd,5w5s jd ration?

  An object starts from rest and undergoes uniform acceleration. Duriqf+fvxp3 84 zhng the first second it travels 9.4 m. How far will it trfv3fh 8p+xzq4 avel during the third second?

  An object is moving in a straight line with constant acceleration. Initl3,t nc9s9uhxv7ah;xuevt 0lr 0-nf 4ially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s.alnlt 0hvxnsru t4v, u ;9-3fxh 9c07e How far does it move during this time?

  A car starts from rest and accelerates uniformx4fo-( f92m bvhrj2cw 6 nd,yhly 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 rogn6 gs846c 4nwc:0durl vay9k ad 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 t6l 5u lkg z6,crzxw5 8 itmyq14*t zhc:)rpgl5hat has been waiting at the intersection starts ahead with a constant accel:45,5mug czzrq8tl hwg r*lx )zk5lp616yct i eration 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 su1z /ypva -lys aboe:; .5qei+urface of planet X where thq-/5 y pzu+. a:sabvl ;eyoei1e 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 ofwe 5ruq guj 4 xtsb:d5zp y*eun-+3(x, 12 m/s on the surface of planet X where the acceleration due to gravity is q xbeuxun535,rus tjd:4 e(z+y*g-pw $1.5 \; m/s^2$. 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 su1nmdhdf+mii 2.ii )u.* r lir.rface of planet X where the acceleration due to grav.nii*hm.rlu 1. )f+md iidi2 rity 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 u+k 7gnl hoh8y7pward with a speed of 14 m/s on the surface of planet X whereh+ 8ngk7 7olyh the 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 usually cs3j9eb p: 3bc(xjt(u greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far cb (9c e3xu 3tpjsbcj:(an you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. Wi;fd 7h8zm3fb6 u-qdnhwa(2t hat is its velocity after 3.00 t6i 3d 7f( -8fmuad qh2;nzbhws?

  A bullet shot straight up ret p7kx u)zb01xfurns to its starting point in 13 s. What is the initial spee1)fb7xkz x0p ud of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does it take tt)rmb3(nf3vphx/h r 1 o return to it3r13p t)nr vxh(fbhm /s starting point?

  A ball is thrown downward from the top of a building wit bd3f) (jv;po;ims: , ugd)wivh an initial speed of 20 m/s. It strikes the gr,vpu) iw3d;sdbm( og :v);jfiound after 2.3 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in nu mz- qc :mrszej+ckze(6, ,g4t--trjzmerical value in the bl :t6j jcec+me-t,k-z(-m, s rz rgzq4zanks)
(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 stu,5vy9muao xk+, r x3nraight up into the air with a speed of 44.9 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 = 1.00 jt2k1gy,o;xmwu (0hz;gtmg+x5g ga s?

  In Fig. below, what is the zx/ 6u6)be/5 dj)dw+dirt mqsvelocity at t = 2.5 s?

  In Fig. below, what is the velo 2,g:v i9oghdw1k/ we,l./ragw tqh.kcity at t = 4.0 s?

  In Fig. below, what is u;uroe;j5 v4ibs2 pn)the velocity at t = 5.5 s?

  In Fig. below, what is the averk 2sr26hqr 17 ec;:wlpg tj1*lo l7shsage velocity from 0 to 4.0 s?

  In Fig. below, what is the ar)6vk.q. vfy 5qrr l8rverage velocity from 0 to 6.0 s?

  In Fig. below, what is the accelerat kia2l .,jc(nwion at 1.0 s?

  In Fig. below, what is dx22vai; 76.s4 msnmj ksjr v5the acceleration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 to 5./e98p9zv7 wa 0:f ub) khs2g(whywaxs 0 s?

  In Fig. below, what is the st ymh4 q)i2a /mb;b7gaverage acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 towaxx5 (8 xgplj ip ;,n,yt4 2 ;ue2z2qga+cecw 8.0 s?

Does a car speedometer measure speed, velocity? {speed|vecq:r ))(v4 dfidhuqi vmlx, ,;locity}

  An object can have a varying speed if its velocity iz yqf)bj3a k3npm/i,c;+6/ wrtvp b5 bs constant.

  The velocity of an object can be negative when its acceleration is positive0xd g fzna fdgcvpru)+gg-9/n *:x/:e.

  If one object has a greater speed than a second object, the first must have a* ptztc(fg olf2*+e;v grgl2 *o;ff tc(+vtpz* eeater acceleration.

  Two cars emerge side by side from a tu(qdtwmi/955 hmu jva8yk(v : nnnel. 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 a- .y+hch+utpf s its acceleration decreases.

  A baseball player hits a foul ball straight up into the ai*.p ac4)fkfxlr. It leaves the bat with a speed of). f *apxf4ckl $120 \; km/h$. 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 jkrhtec- 2ie-j o6/w/speeds up, what is happening to its acceleration, how/k hjc26jreti e-wo/- does it change if air friction is ignored?

  As a freely falling object speeds up, whad0v (e0p h h.q :tgbjv,hz.x k6*nin(kt is happening to its acceleration, how does it change if air friction CAN NOT be g:(jnh0.(z dq6,* xe.kib vh h0pknvtignored?

  An object that is th,t,s0tgtg:q nwamc 55y/dy)p rown vertically upward will return to its original position with the same speedtcw)p :t5 ,a5/n,qgg 0 ystymd 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 velocity and nonzero accfs q q r ;78;c7/nog(:je9hn fmfdc.,kt9uympeleration at the same time.

  An object can have nonzero velocity and zero acceleration aj-te(1yt sg p0t the same time.

  An elevator moving from the s1e.,(q;uleufftw*bkeh i8/ b econd floor to the fifth floor making no stops along the way has zero acceleration allu*.wekh bu ;f8fi1l,/ tb(eqe the time.

  A rolling ball moves f.o/e8xem2 bme s ;(xm o/s7wzlrom $x_1=1.6 \mathrm{~cm}$ to $x_2=-6.0 \mathrm{~cm}$ during the time from $t_1=1.5 \mathrm{~s}$ 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 $t_1=-3.5 \mathrm{~s}$ is at $x_1=3.2 \mathrm{~cm}$ and at $t_2=3.3 \mathrm{~s}$ is at $x_2=8.1 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps a 3r7nwjb-c3x 1n:sdv sround a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.2 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its tr)jjh9+ pg/phx;tci o6ainer in a straight line, moving 90 m away in 11.2 s. It then turns abruptly and gallops halfway back in 4.6 s. Calculate (j px hhp/6+t9go)i ;jca) 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 fromz*9m nvy +kfm5 $11 \; m/s$ to $23 \; m/s$ in 4.5 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 fromhtiqzcjg7h7)a58 yh. $23 \; m/s$ to rest in a distance of 56 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a spej y:tcukw .iy ((h;bu0ed of $30 \; m/s$ 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 the blocks5 rz:+)uxhdq m7yjhi ( to essentially top speed about y7qu:d5izhmjrh) x( + $10.1 \; m/s$ 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 frogp;b 6kh; onpt:l2 tjr7afm3r9g b++e m a speed of $20 \; m/s$ to rest in 4.10 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car lea4mexz::3to5 ns0sp-ta tq(-pk(jkcun; fib7 ves skid marks 92 m long on the highway. Assuming a deceleej ;qcaf toisn5-( 4t(xs t0kbpz7n3m-::kpu ration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goinfta mvl134y-a g $25 \; m/s$ 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 yn 6xgp2 5ed4cuhvx+f1.p8kw30.0 min. After exactly 27.0 min, there are still 1100 mduxy v4h cw15+g68n e2p x.kfp to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$