Suppose that an object travels from one point in space to another. Make aj. rn +riuq(w 8rt6m.v comparison between the displacement and the distance . wj+.8m v6rtrrqi (nutraveled.

  When is the average velocity of an object equal to the instantaneous qhp2nmt:tgl ,lx48e ao+ 0tz4velocity?

  A new car manufacturer advertises that their car can go "from zero to sixty kgvuml2 nxf (x*; r8g0in 8 s". This is a descripf vnxg 8ml(kr*20xgu ;tion of

  An object moving in kcntxirm4 ,(d;2b ,(t xsrvd4the +x axis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the Ebp) w9yw,tuawk-e9 ; qw1t ap:ast (+x direction) begins to slow down as it approaches a traffic tk9p;a:)w p1, uaeqy9wt- wwblight. Make a statement concerning its acceleration.

  Suppose that a car traveling9kpdb 6 terr+vnem ()).,karv to the West (-x direction) begins to slow down as it approaches a traffic light. M.)ed (m9e +br)k rnt,p kvv6raake a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Ma,ou+ssrak 1*pzjlzb)2iyd8 5ke a statement concejb kdz)1,y 8rsa+ u5zsipl2o*rning its acceleration.

  If the velocity of an object is zero, does it mean that the acceleration is zec7edi,zn xlr o08v hsyw/ 30(zro? Support your answer withxce ov0d i,zlwy3 h(0/7nr8z s an example.

  Can an object's velocity change direction when its acceleratith wci:ii ;.,yon is constant? Support yoiw: ,t.i y;cihur answer with an example.

  Suppose that an object ih;i)co25k4ho rsu z kwqd9(d 4m b2x9ds moving with constant acceleration. Make a statement concerning its motion with 5hq44 2w zokih cbs9d du2r(xk);9domrespect to time.

  Can an object have increasing speed while its accelerchc p zt- 83bo8:cuh.mation is decreasing? Support your answer with ah bc:cphtm 3zoc-.u88n example.

  Suppose a can, after an initial kick, mv56 jt w2vmz/2ln4*mqzsr7 jqoves up along a smooth hill of ice. Make a statement concerning its acceleration.mjnq7*s5zv4/6 r2vml 2zqw tj

  Under what condition is average velocity equal to thro7 7 lae.vd2pdzfg:13qfo4xlx l n)/e average of the object's initial and final velocit7rn:a4lvl1). /qf po2 fdozlxg xd73ey?

  Objects A and B both start at rest. They both accelerate at thmc,a7:)tt ;c kq1xzgue same rate. However, object A accelerates for twice the time as object B. What is the final speed of object A compared to that of objec,1cx)tka ;t:mug z7c qt B?

  Objects A and B both start from rest. They both accelerate at the same rathpg:*b 4q ,oroe. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared to that q pohr:b*4,goof object B?

  When an object is released from rest and falls in the absence of friction, whichw zfx6e 4r:qyu h:+cj+ of the following is true con j+ 4rwu:xe :yq+z6fhccerning its motion?

  When an object is released from rest and falls in the absence of friction, )erm-ruw. ca)which of the following is true concerning. -r)am)crw ue its motion?

  Suppose a ball is thrown straight up. Make a tf)gkt9e *1 fl statement about the velocity and the acceleration when the ball reaches the highe9gkelft ) f*1tst point.

  Suppose a ball is thrown straight up. What is isbx0h0ijek u4+ pe-g /ts acceleration just before it reaches its highest uxp/sj eegk b+4h-0 0ipoint?

  Suppose a ball is thr))p uj9ugn2rgu 578u9 ogi fefxh 05idown 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 baghnj9g p fii8)5uduregu052 of 7u9)xll is going up.

  A ball is thrown straight up, reaches a mzxp(; 8j 7f e1rfpdtnli+ 0pd.aximum height, then falls to its initial height. Make a statement about the direction of th(d ef p p0z x1fild+nt;7j8rp.e velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance.*,r j.day2gu)b: gf owhi u13w Make a statemen y*ub2rou3a)hj: dif1 .gg ww,t concerning its acceleration.

  Suppose a skydiver jumps from a high-flying planeii :)drx7 dl2pa*6 lpl. What is her acceleration when she she reaches r*l)2d:i x7ipladp6lterminal velocity?

  A ball is thrown vertim/8 u -;9hchmgg y;cpically upward with a speed v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the secy;8/cpgugmmc- 9 i;hh ond ball to that of the first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, bahzq yl wk3 9te.b+9og+ll B is dropped from the samegzt39k+.h ylq +ob e9w building. As time progresses, the distance between them

  Ball A is dropped frjc11 k lbm(:gh quy;a.j* ,ybjakh /*com the top of a building. One second later, ball B is dropped from the saca bbh*, j;cl:a / hkj.g11umq(y jy*kme building. As time progresses, the difference in their speeds

  Two objects are thrown f2r8 c.b2sjf 7hhp nigd ,tuwm.11 *lmzrom the top of a tall building. One is thrown up, and the other is thrown down, both with the same initi*in1.. 1jt,g2u2m7hhf l w8zrsmbcpd al speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a buildinwgv3aks) s-81 hu ti6dg. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air s 8ud6kv-1 iswt)h 3agresistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. Thqxr);us wbjp )l0 :tp4e position versus time graph of this objeu)s)jxpplqb t:r;w40ct is

  An object is moving with constant non-zero acceleration in the +x axi izul znqsf5 i5yb3457s. The position versus time graph of this 5uizqn4 y5i75b lfz s3object is

  An object is moving with constant non-zero velocity in the +x axis. 2sxdf /.f9aca:ww:r n The velocity versus time gra:w/sr: cxafa9d.nf2 w ph of this object is

  An object is moving with constant non-zero acceleration in c;.vvr67qyx6itv v6 z g7rg1m the +x axis. The veloci vtcg v 6vqg;r67.7yr mvxzi61ty versus time graph of this object is

  The slope of a position versus time grapht: 4que67qnd z d7;iyx gives

  The slope of a velocity vers2 . x:p fn2tef5csgqr 2z.-iub 8brcj-us time graph gives

  The area under a curve in an acceleratibtvz,zt 0c zk8svb)1 16rva 0gon versus time graph gives

  The area under a curve in a velocity versus try .c- *ck8a8 yecvhb1ime graph gives

  If the position versus time graph of an object is a horizontal line,busu *gxz o(o29n jaa;r,yi20 2 rjod: the object i9gj:u;zu 0r jon*x, aros diba2o y2(2s

  If the position versus time graph of an object is a vertical line, the objecta*abgchq)( of+ot,-bvv 5pl 7 is) -pbo vtoh7 +bfa(a *qclvg5,

  If the velocity versus time graph of an object is a horiznabn3+7d /t he.0a ) msmw8tpza: stm2ontal line, the object a:/e8tspsm 3db7nz0h.+ nm )t2aw t mais

  If the velocity versus time graph of an object is a straight line maki5g(8 oqlv l*eang an angle of 30 degrees with o5q *gl(ae 8vlthe time axis, the object is

  An object moves 15.0 m north and then 11.0 m - gl-s9 pmwm.esouth. Find both the distance traveled and the magnitude9p mm sl-w.-ge of the displacement vector.

  A boat can move at 30 km/h in 5/zx 8cjk(2y/)p)gliw6nta 0 usg dlw still water. How long will it take to move 12 km upstream in agi/l2 gwd lyn 8x 0j(a )tz)cs/5k6upw river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 ysx q pt4+z5o y4eu7k*mi = 1609 m)

  What must be your average speed in order to travel 350 km in 5.15 h?8 q5 cc/ni9wkv

  A runner ran the marathon (approximately 42.0 km)e6 gls6(fs4v xaslwd9-qn;(f in 2 hours and 57 min. What is the af lqal(nwsge6;d f 9xss(4 6v-verage speed of the runner in m/s?

  A car travels 90 km/h. How long does itxf +myxrs s* j8lwsz93e0k sm; mz4*+ tt:+bie take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one yeadg7fhh-7+bt m:w)i xwr. The speed of lw: t)7wbmf-hxdgih+ 7 ight 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 straight road and you look to the side for 4 9z *x6f-)ebvf3+m8fot +v6xkub ytxl .0 s, how far do you travebf6+ -o+6bxztu) 3vx 9f 8*x kfmtelyvl during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), *ff zo07d8d b vti82ozin 100 s, your average veloci8*0d7ot2iz zbv of d8fty is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km 5elhh r( gtlp /o12 pi-d-uea+east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. eohda-2 hr p1/up5+- tliegl( 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 v:6w9pxxzm,/x oj/ wleast, thevpx,:w x9wxzmj/ 6/ oln 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 velocity?

  You are driving home on a weekend from school at 55 mi/h foe/piyw.w y24sr 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hou/pyw2s4i.ew yrs and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80gc(eot)2tlgh k ui:09 49j6 avl vdkj; km/h and 160 km at 100 km/h. What is the average speed of the motorist ck 9lvead4j :2lo)tgh ;6g (90 iktjuvfor this trip?

  A motorist travels for 3.0 h a eg,knko vg80n-68sma t 80 km/h and 2.0 h at 100 km/h. What is her average spe-8g g s8k 0vkeo6nn,maed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h nortq-v) 7visrqs* yu;h9c h for 750 miles. What 9v) ;ruyqh 7c-sqsvi* is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for 8y 8o*+fuv6 aiy*aksbw:de+6 lgl zn.team A can run 100 m in 9.8 s. His rival, the anchormko8bw+ ne8y * 6svyz*ldfaa u:+lig.6an 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 stop after 13 s. Thef n-6 5+ewdik y4z/lsm car's average velocity during dmk/ wydnie+zfs46 5 l-eceleration was 34 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed xg(e4te;m( )vtau(gmpug ru:d)y 1+hfrom 100 m/s to 160 m/s, at the average rate of ; m(uu( ) hmag)(geyeurvdp + xg:t41t$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acceleratesd nt9u 5gkd goc,ie:7.b5 syc1 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 accbu+;uacc0 qc w8u;0lj5j9 ho jelerates at $4.0 \; m/s^2$ for 5.0 s, then maintain that velocity for 10 s, and then decelerates at the rate of $2.0 \; m/s^2$ for 4.0 s. What is the final speed of the car?

  A car travels at 15 m/s for 10 s. It then speeds up with a constant acceleratio vx )8:8f e (g6xc0qhfgwik+oun x0f (fu e6 w8h+):ogkvqc8xg iof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity ofmkmbt2+0s+y big*q f7 5rsp,s 7.1 m/s experiences a constant acceleration osb 0s,mpm+7 ytiq2 *bg+ fsrk5f $4.2 \; m/s^2$. What is the cart's displacement during the first 7.7 s of its motion?

  A bullet moving horizontally rot*(nlj h j0kg67hd(87kkvbto the right (+x direction) with a speed of 496 m/s st7kd(lkg jvb8rhtn 0 6j(okh*7rikes a sandbag and penetrates a distance of 53.12 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircrar c/swd8 f,s84+ejvmift carrier. It reaches 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 catar4c8 jis/d+s8m ,wefvpult?

  A car starting from rest m g)vvk*js 6*byoves 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 80tlkm/-)ppf *y/rsn i.5e :ptc m/s in a distance of 200 m. What is its average accele-*.)eyt m:rkncs 5i/ppp tfl/ration?

  An object starts from rest and unpnqqj+aa : ac k0r/)m/7nk9a ldergoes uniform acceleration. During the first second it travels 8.1 0+ aja c 7nnrkq/)p/l:kmaq9 am. How far will it travel during the third second?

  An object is moving in a straight line with conse vznb(5bdsxh os/ 2,8rdk,r2 tant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How 2x82bz(dsh ,/,d nv korbser5 far does it move during this time?

  A car starts from rest and accelerag6xd 364c/, fliisxyltes uniformly at $3.0 \; m/s^2$. A second car starts from rest 6.0 s later at the same point and accelerates uniformly at $5.0 \; m/s^2$. How long does it take the second car to overtake the first car?

  A car with good tires on a dry road can deceler)aa -*wha8 n/pfl:oh0zef*0mhlckc( ate 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 lig, jegnz 90p tf6*wpiv3g,1pijp3ox x2ht turns green, a car that has been waiting at the intersection starts ahex,13eo2 wtpijf0jv pi g6n,p9 *3zp gxad 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 upwa5s,* :q8fko .bfdu(j g rt;wkyrd with a speed of 12 m/s on the surface of planet X where t; oyj s.k , dqftf85krw:*bgu(he acceleration due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward dd+tyv hw0r-b pq1s ,x,6 d, y6:ipk 6rqz*vhtwith a speed of 12 m/s on the surface of planet X where the acceleration due to gravq t i+br:pxwz, * 6pt61dvry,6d -,v0hykhsq dity 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 m8:; xn7. rmf*4qdk4e6g pjiz)u r scur/s on the surface of planet X where the acceleration due to graviz4 d8 r:;rc kpfg46jr e*mxiqn7 su)u.ty 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 planet X wgt/r-4 ge b6m9mknp;ez m34jvhere the acceleration 4 e 4nj9erm k6t/p;3ggvb-mzmdue to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually greater thb(3pmp re* if9an 0.10 s. If your friend holds a ruler between your fingers anp3(9*fm bepri d releases it without 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 itsq;b(; d w +bmk-juatp9 velocity after 3.00 dqt;b9w( ;kpb-mj + aus?

  A bullet shot straigh3j ig u,bdczu b+n2/qc4(y5 wat up returns to its starting point in 4 s. What is the initial speed of the bulli+/wg aq, c53bcdju4 z2 u(nbyet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long does it take hhd0rgdg/ pjvj* ;8jwu r2z -7wlu76fq vh1c2to return1 8gg7juvc2 6j7/fwwhh ; hzd-rp0vuqr j*2ld to its starting point?

  A ball is thrown downward from the top of a building with an initial speed uens 3z2ugzp;6to6 /cof 12 m/s. uz6/zup6 ;ot2 ns3gec It strikes the ground after 4.4 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in numedim,dictkesf ,u0;hzy-s 169fkfn l 5u1g3i-rical value in the gi,l3cfe1k5y6 uidt hf0s- ,9u -f ;z nksimd1blanks)
(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 (y)x9ct fux d0 (4jcxy(nik0 ye.z7s nair with a speed of 34.2 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 3 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 veij6a r79ckr.k28iil *anipx 567pkbglocity at t = 1.0 s?

  In Fig. below, what is the velocity at t = 2.5)0go33eixf t4nfe9nu s?

  In Fig. below, what is the velocity at t = 4.0 s?2tub7pc6s(sps, +4t6pv h zyl;mujzk .4 rht6

  In Fig. below, what is the velocity p:lbs:xj1j( /1ff0vn3 rki fu at t = 5.5 s?

  In Fig. below, what is the average velocity o3l 5 1s,c3,is7jdqu crkba9 ofrom 0 to 4.0 s?

  In Fig. below, what is the average velocity prii z -6lzhog(ti 8d;;j .7ccfrom 0 to 6.0 s?

  In Fig. below, what is theg3o o(9oc +sj (ug/0eljg .zfq acceleration at 1.0 s?

  In Fig. below, what is the acceleration at yuu6krj ;1 l,)oyrjj/ 3.0 s?

  In Fig. below, what is the average acceleration from 0 to 5.0 s? f7b g-zn5h3zf

  In Fig. below, what is the average accelerxu6gw0p6ch;mllfpe )32 hj / sation from 0 to 8.0 s?

  In Fig. below, what is the displacemenz 6u1 jsnme1( bvr1,rz57y6ouyrr ,ao t from 0 to 8.0 s?

Does a car speedometer measure speed, velk 8y1mt31obbeocity? {speed|velocity}

  An object can have a varying speed if its velocity is c f -ntwy5l+c1aonstant.

  The velocity of an object can be neqf8a *pk;sn)vg 2r mz(gative when its acceleration is positive.

  If one object has a greater speed1 of.j7aoyc 6x than a second object, the first must have a greatera6 7o1x .cyofj acceleration.

  Two cars emerge side by gn+ew2e /rtvc- xu9p7 k.zcw1side from a tunnel. Car A is traveling with a speed of $60 \; km/h$ and has an acceleration of $40 \; km/h/min$ Car B has a speed of $40 \; km/h$ and has an acceleration of $60 \; km/h/min$ . Can A will pass car B at the instant they come out of the tunnel.

  An object can be increasing in speed as its flvkrbku 6be2+l t+le:+8 6ewacceleration decreases.

  A baseball player hits a foul ball straight up into the air. It leaves the bat w y.pwxyyy26,/ gg a5s6nxzy ac3j4-uwith a speed of pas.u2 yx3 y-g4x/5gw j6 anwyyyz,c6$120 \; km/h$. 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* 826ex glzx fzias9j.v4k z3s is happening to its acceleration, how doez*z 9fkesx jia 8.sx4g23vz6 ls it change if air friction is ignored?

  As a freely falling object speeds up, what is ha;nksz(sxw o/ 8ppening to its acceleration, how does it change if air friction CAN NOT be ignorn 8(sskw xo;z/ed?

  An object that is thrown vertica 4o6qve0 wg*lf7+fzzmlly upward will return to its original position with the same speed as it had initially if air resistance is negligible. I+*06zfwm f qz7olv4 gef air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration at the same tim;c +*c0 xpcuuze.

  An object can have nonzero velocity anjvkm9((tq9 ej qu-cj0,g ds6nd zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor making no stops 9kipt// e e-r(c yhykv 9zx m4z7id4w9along the way has zero acceleration all yh vckt 9eedz9(7/wm4- r4p9i y/kzixthe time.

  A rolling ball movesc1b zrpqv2sihko: 42x kk(1vk5-v+p n from $x_1=2.1 \mathrm{~cm}$ to $x_2=-5.1 \mathrm{~cm}$ during the time from $t_1=0.9 \mathrm{~s}$ 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 $t_1=-2.6 \mathrm{~s}$ is at $x_1=2.5 \mathrm{~cm}$ and at $t_2=3.9 \mathrm{~s}$ is at $x_2=7.7 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps ufjq3r 8 3,ivuaround a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.2 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 straigin)i.qa p npllf(a;* +ht line, moving 114 m away in 10.8 s. It then turns abruptly and gallops halfway back in 4.6 s. Calculate (a) its an.p qfiil;pl *a) +na(verage 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 fromc yzh;b-epgpef . 4e+1 $12 \; m/s$ to $22 \; m/s$ in 4.3 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 from5sdy*qcnjg5/ k0 +qmj $20 \; m/s$ to rest in a distance of 60 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach 8,j mpw5 2xy f9mbxo9ua speed of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.9 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speed abov4x)wfh je8:cut x4:e vw c)8fhj$10.6 \; m/s$ in the first 14.1 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 uniformly fjrj86bg w;2v q r6q1dvr1w1bs rom a speed of $17 \; m/s$ to rest in 5.35 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 highwvvv* e.rumxh1e5yicq yjp1 5x::. uz 8ay. Assuming a decelerationc.5vx vim85 vhy : z.*qj:pxre1u ue1y of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck g(esy va6()polq vt1;g *)q ffuoing $25 \; m/s$ 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.o*9otqjk9wawj7w4nlv 2n1 -d After exactly 27.0 min, thq*d49 owo lva29njtjkww 7n1- ere 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?    $s$