Suppose that an object travels from one point inie+4ey e.if-:a0 i4(k:v djv mszsk /f space to another. Make a comparison between the displacemes vij .ekdi+ e0:s f:4vfyz-iae km/(4nt and the distance traveled.

  When is the average velocity of an object equal k6hh:r8xq;z vj u4yq6 to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "fyks atxe )l 00nuqg4qa)5/bd 5rom zero to sixty in 8 )utylq) qaeb xg450as /ndk5 0s". This is a description of

  An object moving in the +x axis experienc1a*k y0 (bo7(nvtphdr;*z lhfes 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 slowu l /m-tibj6b u1 1vee:s3h5um down as it approaches a traffic light. Make a statement concerning its accele:vb/iumhjmbstu131u- 56leeration.

  Suppose that a car traveling to the West (-x direction) begins to slow down g:6 rl xp5ucq5/xt6cm;c 7pcpas it approaches a traffic light. Makeumlp66c ccq7 xx/gpp:;r55 tc a statement concerning its acceleration.

  Suppose that an object is moving withg xmclbzl w0 bd1asy+7g(-1-d a constant velocity. Make a statement concerning its acceleration.byx1zcw-+- 0d(d b amg 1sl7gl

  If the velocity of an object is zero, does it mean that the acceleration is zek 98hha3n vy8yro? Support your answehhy88kn 39ayv r with an example.

  Can an object's velocity change directi upgan0qd3w )2(kg9b5cv2l9 jacxrv6on when its acceleration is constant? Support your answer with an example 0c(2 ancu35g r2l9bj 9v6akwdpxgq)v.

  Suppose that an object is moving wit 5x.bh-x;vexbh constant acceleration. Make a statement concerning ihxb.5xb vex ;-ts motion with respect to time.

  Can an object have increasing speed whil (pk asxe:*sw1x.f,:j (bdwn ke its acceleration is decreasing? Support your answer with anwfp:ane:w k, xj*kss d( (.1xb example.

  Suppose a can, after an initial kick, moves up alo)/f o -,jtz46 g*ol3ubes ferh2zfx7kng a smooth hill of ice. Make a st /erz42efz6s b)*xluh 7-o3,oj fkgtfatement concerning its acceleration.

  Under what condition is average velocity equv5mnuw3sevxgb 3z3)e 4 b 1.f dh3(yfzal to the average of the object's initial an x y 34.zz(b13fnvv fshmg5b)ude33ewd final velocity?

  Objects A and B both start at rest. Thwi o4+z1sai (/uo dqp7ey both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the final speed of object A compared twa1 uopsqo /(zdi 47i+o that of object B?

  Objects A and B both start from rest. They both accel9(t,gvvzs im92n a4*dcchp *xerate 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 that of obj2v (,**4ah 9scmx gpi c9tvndzect B?

  When an object is released from rest and falls in the absence of friction, whic q1p9yr xdhq1 p:,,eiqh of the following is true concernineqrp p ,iqd yx:h91,q1g its motion?

  When an object is released from rest and falls in the absence of friction,68 togly+ncz 58 +2e+guxowsl which of the 8yulox g+wcgzt5+6 o2le8sn+following is true concerning its motion?

  Suppose a ball is thrown straigh rwgdb10xtz.7 t up. Make a statement about the velocity and tbrw 17.0x gtzdhe acceleration when the ball reaches the highest point.

  Suppose a ball is thrown straight k /h05s:qgcih up. What is its acceleration just before it reac/ gh0hik:sc q5hes its highest point?

  Suppose a ball is thrown straight up, reaches n ,m opr 1e*csfyl h/bw,s d*5psz64h4a maximum height, then falls to its initial height. Ma,p,rl/ 5w4dp6*fs4mczhhs*b1e ynoske a statement about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to its rqo4jh zw.v01kkto7f tah8kz y-*p q;es57)r initial height. Make a statement about the direction of the velocity and acceleraz)q ;rka wzkhk50vjept.qsr4*7 1fo8h 7yt-otion as the ball is coming down.

  Suppose a ball is thrown dow ,ptgboy0wi 7ud2z p0:nward in the absence of air resistance. Make a statement concerning its accele, 0pu72togi 0ywbzdp:ration.

  Suppose a skydiver jumps from a high-flying plan b3 b1op :/p akam)/gunhn.x4j6co8j le. What is her acceleration when she she 4c.1gnu pa8o3jnk6op /:bhl/xa bm)jreaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identicalzkts ki/q/ ip1n20kg01a /fcl second ball is throwng0sf q1iz a/t//lkkkpc0 21n i upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from the top of a building. One second later, ball B is droppz+t;r(heoxgs ,ou 6y8g 6brj-t5b 6y yed from the same building. As time przryhet,gy8 or-5g6xu+ 66tb bs yj;(o ogresses, the distance between them

  Ball A is dropped from the top of a building. One second later, ball B a5,.wwt*53uym skfyk -; nx+ vvuiog0is dropped from the same building. As time progresses5+x 3., fv*ugwyi kmw ; 0ausnt-voyk5, the difference in their speeds

  Two objects are throc-m vk3rfk .l6wn from the top of a tall building. One is thrown up, and the other is thrown down, both with the same inikk-flm 6r. 3vctial speed. What are their speeds when they hit the street?

  A brick is dropped f+deo 8:v smy ps3wyxc )z67f)vrom the top of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neglect ay+x w 8)p)o3fvs 7ye:6m vdszcir resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity ii,pumkh;y.2)n .z hienk+twv )- k4uin the +x axis. The position versus time graph im)vhn izp)4k +ik..ykhe-u,w2u t;nof this object is

  An object is moving with constant non-zero acceleration in the +x axis. Thb gm04nudyn d,(lt.tyb-58n n;z m7mj5 sus1 te positiou-s 1td;7lm ( 5tnyb,5buyn8gsm.0jz4ndtnm n versus time graph of this object is

  An object is moving with constant non-zeroiy03. fr(dqea/ /k gea velocity in the +x axis. The velocity versus time gadiq/re .e (g0f k3y/araph of this object is

  An object is moving with constant non-zero acceleration in the +x axis. The b5g: qd +d(um)6liil9/h mjhj90s urx velocity vermxj l/ h9d5udbsg96mi i)lh+qu:(j 0rsus time graph of this object is

  The slope of a position verslzao.zh+msv3la+ uzh g 9155mus time graph gives

  The slope of a velocity versus ti x0ct*9dm30u;y sa zcvme graph gives

  The area under a curve in an acceleration versus time gr w)i,pyq vu( xqw+.kn3aph gives

  The area under a curve in a velocity versus time grbl+h8h j+o1s daph gives

  If the position versus time graph of an object is a horizontal line, the objs9hwf/g,t0s -fj o5dpect isffod/0s,9-wph t5jg s

  If the position versus time graph of an object is a vertical line, the object isyuj,si 9j; q 5q/yd)hbye.s eym279 klyy)l9ds5 km;u j/yh7q eij29byeq,. s

  If the velocity versus time graph of an object is a horizontal line, thb ;9em3xnel4z e object is 4zexe9m3nbl ;

  If the velocity vers wk w/.qlnngksi4t yw3t9nr.bha0ak / y3 ;l,*us time graph of an object is a straight line making an angle of 30 degrees with the time axis3; gk0at/ly/tkn4nr h,ww n k3qwlsa*.y 9.i b, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both the distance traqq)/ml gwi4a+veled and the magnitude of the displacement ve q/i )+qgalmw4ctor.

  A boat can move at 30 km/h in still wat a/kxvd7w35 ;)drn9 hop mi) dsy 0d/o/0jchqser. How long will it take to move 12 km upstream in)9/ s/ yxi ho5pc doh0w;ds3nm)7r0 /qkvjadd a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 16qn(u3 pwy i; rdo-0:nr09 m)

  What must be your average speed in ooh2g6iv9utifv )5bf . zhxl1 ztp *g-8rder to travel 350 km in 5.15 h?

  A runner ran the marathon (approxix*gk,*q(su3 ztbd- rumately 42.0 km) in 2 hours and 57 min. What is the aver xs-(*dqr 3uu,b*gtkz age speed of the runner in m/s?

  A car travels 90 km/h. How long does iwl 3r 0n7 skc7pjbje(45hf ,lqt take for it to travel 400 km?

  A ly (light year) is the distance that light travels ae8nl/y*ey 8g10s19 e ibgkjpin one year. The speed of lab9 8 leykpe* ejs1 /0gin81ygight 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 ththwu8stw 8nml/yu94 +u9; hbwe side for 4.0 s, how far do you travelmy9uu nwwt8w/ uhh8t;4l + s9b during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in . 5uclkmue b 3q;i;p4g100 s, your averagup 4mku3.qlb5 ige;;ce velocity is

  A polar bear starts at 55bwa rn:mp :u56e:cv xcm)dok zz bzrj+ 1:f: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 : r+cmb1uj x:dc):5rom f6z p:ve:bz5znka5 w trip takes 45 min. What was the bear's average speed?

  A polar bear starts at thelixkw3iv 7k(fc0 t )2v North Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to retulv iwx3t0 7ifkk2(c)v rn to its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend (zr3*d yeev3vfrom school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive hy3dz*rvee v 3(ome after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km alrri7 - 5w7qpfa *yfm,t 80 km/h and 160 km at 100 km/h. What is the average spee*5,r7fli wfp am7rq- yd of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her av8 rx9np hvw7dn*rjzqmi +j -+-erage speed for the tri 9n+z +rwvn7 p-jrimh8-jdx q*p?

  An airplane travels at 300n/ gj/;ml xx:lcguj .. mi/h south for 2.00 h and then at 250 mi/h north for 750 miles. What is the average speed for the; j.:./x x/gngmcu ljl trip?

  In a 400-m relay race the anchorman (the person w76yhjcr) *p mzp2)xwek9ms8 *4fqb lgho runs the last 100 m) for team A can run 100 m in 9.8 s. His rival, the 2lmyb*e4)m 7h9pxwcz j)p r g8k*q6sfanchorman 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 c 0-.rw)jglcanj;dag,omes to a stop after 8 s. The car's average velocity during decelerati.0-wgja dj);a lr c,ngon was 65 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at 3rwsr0mo-ueobk 0/5s ;+azo ethe average rate of 3/mz+soe ; 5oea0o srbuwk0-r$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate s -k t8*/;k0za7xxrf5vt y sxniwpt-1 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 accelx4e4(+vkcw(0j fd ukn :ep/iuerates 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 acceleyw.+ )yq*y9 eilvzf qc f,4uj*ration o*yyv 9f+ )ecj4uzy qwi*qf l,.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 5.5 m/s experieny p7 0div+67j: x/mqzxer,mzu st 9tp-ces a constant acceleration ouzi 0,e-x qt7pt/pm6s9xdr+m z vj7y: f $5.0 \; m/s^2$. What is the cart's displacement during the first 6.1 s of its motion?

  A bullet moving horizontally to the right (+x directionho n,;f1re dmr xpn,45n-p0xp ) with a speed of 338 m/s strikes a sandbag and penetrates a distance of 11.64 cm. What is the avep o ,x5-n;40erpndrm h,nx1pfrage acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launcihha;k6xw1) ched from a catapult on an aircraft 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, k i;c)x w16hahwhat is the length of the catapult?

  A car starting from res22 ;xlih2vjnvb:x v:wt moves with constant acceleration of $2.0 \; m/s^2$ for 10 s, then travels with constant speed for another 10 s, and then finally slows to a stop with constant acceleration of
-$2.0 \; m/s^2$. How far does it travel?

  A car goes from 40 m/s to 80 m/s in a distance of 200 m. What is its average ace7mokmvrv7k0 4m48z,s sy6qc,0k6m7 c m rkeo4mv78qz4ysvsceleration?

  An object starts from rest and undergoes uniform aud6r b qhp-2s.cceleration. During the first secodqps2 r- b.h6und it travels 1.6 m. How far will it travel during the third second?

  An object is moving in a straight line with constant accelerati k zswpu6h35tywpys1a5/wj9 ;on. Initially it is traveling at 16 m/s. Three seconds later it is travel/5sy w5zt;y3wpusjk1a 6 hp9wing at 10 m/s. How far does it move during this time?

  A car starts from rest and aisdi- 0b + mn 05vrm)kbdl 1.v)bevj+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 dry road can d 4l.5tti rg9hkecelerate 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 that has been waiting avm+x *0s./sci 3a vvzjt the intersection starts ahead with a constant accele+ xsiv.m /jva 03czsv*ration 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 1(v 3v59swaimve(2xqk 2 m/s on the surface of planet X where th vmqv (eai3sv295w(xk e 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 of 12 m/shpce2h. /wep37 x6/qcm0lcr p on the surface of planet X where thh7cl3.2qccph p/p m6e0 wr/ exe 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 shi b84t yvod2 (6,/tmku.w vbourface of planet X where the accelt 2od itwv4u/,(yov8mkhb b 6.eration due to gravity is $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

  An object is thrown upward with a speed of 14 m/s on the surfacw4c w: pi*o2ahe of planet X where the acceap 24:iwch*o wleration 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 greater than 0.10 s. If your jqaq9 o6pj0v *4/bnskfriend holds a ruler between your fingers and releases it without waj4qo0vnsb9a6/pk* q jrning, 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 its velocity a hbxozgbjinq-a, 0 (: 1.1xgghfter 3.00 sg i0x: hxg -1 1zj,nbaqog(.bh?

  A bullet shot straight up returns to its starting point in 11 s. What is y r 54tvstdy):the initial speed of the bulle5 dvy4):ryttst?

  A ball is thrown straight up with a speed of 36.0 m/s. How lon,ndvb,; lmw.xg does it take to retu ,ldwn;bx.,vmrn to its starting point?

  A ball is thrown downward from the top of a buin j0a9dya .nm50rh: lwlding with an initial speed of 13 m/s. It strikes the ground after 5.3 s. How high i ahwy9.0md n:najr l05s the building?

  A ball is thrown straight up with a speed of 3e 47oil-j a5ww0 m/s. (only fill in numerical value in-e ji 4waw75lo 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 d.b7 ,; sq,-udik ejbqinto the air with a speed of 31.8 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 2 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 12 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 12.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1.0 v9c0a-md hws8*nst r qlb 7.h.s?

  In Fig. below, what is the velocity at t = 2.5 s t8kpa9xfr+k 1?

  In Fig. below, what is the velocity at t = 4.0 sko1gj :7p4 klj?

  In Fig. below, what is the velocity at t = 5.5 s x7b;:/dwssge42zjy*, hgyuv?

  In Fig. below, what is the average velocity from 0 to 4t36ux2ofsbo 9imt(4 j .0 s?

  In Fig. below, what is cr )(h1xfm . 8bfepkp97;givsthe average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration ae;7pdxrzk3 z:bz z/x+t 1.0 s?

  In Fig. below, what is the acceleration p j if;4jed0e3at 3.0 s?

  In Fig. below, what is the averagel,kdw r-zk51bz 6ilv)1 xf f;j acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration fro-d a cl07ljq7sm 0 to 8.0 s?

  In Fig. below, what is the displacemenux* chrh- 91y:j8e d272 w-urvfhcfxyt from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speewovv7 w )/r(ahd|velocity}

  An object can have a varyinglclm:nq j47m4ra(h 7o speed if its velocity is constant.

  The velocity of an object can be negat7n9u1+ mdnf r.+8)wb iljsc feive when its acceleration is positive.

  If one object has a greaterw sxx,h)1:u wkg o0fl4 speed than a second object, the first must have a greater acceleration.whw 1xg,4):ukxl f0so

  Two cars emerge side by side from a tunnel. Car A ;yb-*f jnh+hnis 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 acceleration decreasebu)++*fk nvsbs.

  A baseball player hits a foul ball straight up into the air. It leac.dpsf0ee (9ll6/y g19 brnpnves the bat with 9.prf pl (9n/dls0cn gy b16eea speed 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 obq.i(ab i:phxyu*u;u* ject speeds up, what is happening to its acceleration, how does it change if air .i :;byp u*quxuh*i(a friction is ignored?

  As a freely falling object speeds up, w-r*yvmsc1r g*hat is happening to its acceleration, how does it change if air frictionmgv*cy-1 rs *r CAN NOT be ignored?

  An object that is thrown verticalzevl194eb z0sh pq *zp27s,blly upward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciablbeh4p 9lqz lbzz2,0es 7*1p vse, how will this result be altered?

  An object can have zerorsesxe(hsn-(t 40- fv velocity and nonzero acceleration at the same time.

  An object can have nonzero f2zo4pwy+1bfy o6z.fvelocity and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor m: ws2mp;u9 )xkt se,mbaking no stops along the way has zeroseb mus,km2 tx w:9);p acceleration all the time.

  A rolling ball moves - it,go /ux.5vx.f0ixyej4so from $x_1=2.5 \mathrm{~cm}$ to $x_2=-4.8 \mathrm{~cm}$ during the time from $t_1=1.3 \mathrm{~s}$ 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 $t_1=-2.9 \mathrm{~s}$ is at $x_1=2.1 \mathrm{~cm}$ and at $t_2=3.2 \mathrm{~s}$ is at $x_2=8.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight co(9h)fxin+ e-cnw7/ to )tfk esmplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 6.2 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 st bvb quuk ;q;jh1, pktdta b,p3*+49bxraight line, moving 91 m away in 12.9 s. It then turns abruptly and gallops h*kpx9v3,,dbaujt 1+ ;utpkbqb4; b hq alfway 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 froe6v:l y )a7t g6urpvf*m $11 \; m/s$ to $24 \; m/s$ in 5.5 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 fro;/,abp 3cwk9r0f zn wgm $19 \; m/s$ to rest in a distance of 71 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach ak4yz4dfw y2 p:cc+x-i speed of $27 \; m/s$ 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 burst out of the blocks to essentially top speehjhbyk0o;cq)k )v k/6d abouy oqvkkc/;bk)6 jhh)0 t $10.0 \; m/s$ in the first 11.8 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 a s, )q3 spzjdy 5i,n*ghnpeed of $18 \; m/s$ to rest in 5.54 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m l51:7yb7r ad5m 7tq,dwmulojm;f wu;kong on the highway. Assuming a decelerati571u, tdwd;m o:myb;wqm 7 aj r5f7uklon of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truckt:l z0gbcai/jfn+g9 - 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 10x bchs p*mm4:+,000-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. The runner must the mp sc:*+h4mxbn accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$