Suppose that an object travels from one point in space tqr 1od,g+ nn5vo another. Make a comparison between the displannrd,q5vo+g1 cement and the distance traveled.

  When is the average velc.k9aiq8gi0fmt-b 6e:yl /k kocity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises th8q,l;17jz qwp6 wdiwq.tcg i9at their car can go "from zero to sixty in 8 s". Th.9p q w1 tiq,zjq687cdigw;w lis is a description of

  An object moving in the +x axis ex xr n+6/xynpq*lc zm()periences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling a-jm o d.8fac pk c6om)0y3zn(to the East (+x direction) begins to slow down as it approaches a traffic light. Make a statement codny3a(-oczp)6mc 0jafom .k8 ncerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begeu6i;xul0ta k kso7871 x 3 on,ll0kgm2jt( yyins to slow down as it approacheslk72t yeok7 u g;m6 xts10y38ux 0ajnol( kl,i a traffic light. Make a statement concerning its acceleration.

  Suppose that an objec) f.2 kx e7rrlkq:tmt6t is moving with a constant velocity. Make a statement conr7trfq 2:teklx 6k) m.cerning its acceleration.

  If the velocity of an object is zero, does it mean that the acceleration is zeromu2xy 3bx f5v7+ rffe6? Support your answer with a3f yfbxv+ 6x 2uf5mre7n example.

  Can an object's velocity change direction when its acceleration is ctglte+9bew/:tcb l 9 2onstant? Support yourt/ct:b9 + e2w teg9llb answer with an example.

  Suppose that an object is moving with constant acceleratioi+im 7z9jsz,*wg5lmr n. Make a statement concerning its motion with respect twjmim z+5zsl* i79 rg,o time.

  Can an object have increasing speed while its acceq:(1od0 ks m f:fax0peleration is decreasing? Support your answer with an exampleao: f1dm0( 0sf xpeq:k.

  Suppose a can, after an initial kick, moves up along a fl xj;6c sz xavq9/+u/smooth hill of ice. Make a statement concernia 6u v+zj/cx ;qf9/lsxng its acceleration.

  Under what condition is average v.s-9) jgdgyk s03at iaelocity equal to the average of the object's initial and fin t03ag y-ss.9a)dgijkal velocity?

  Objects A and B both start at rest. They both accelerate at the same rate.y4) ,fpv4l-b tf+x*o mvguo 7s However, obje,7t o44ffmvbxu+)vs gl* - pyoct A accelerates for twice the time as object B. What is the final speed of object A compared to that of object B?

  Objects A and B both start from rest. They both accelerate atq2,gcz07. a7qvdd e bwu/sb*0kzd/iw+lpvn 5 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 okzunw+q*7, q.blv 7 0d//wda b2ige zpv0c5dsf object B?

  When an object is released from rest a.ap3 /ai*n ddmq(o c6 e 1:/ew+gddaihnd falls in the absence of friction, which of the following is true concer(de/aimd 3 ea*wg+o.n/ 6ddhcap q1:ining its motion?

  When an object is released from rest and falls in the absence of frictio1nlhjo+quyc1p:l6 qv v9i:f4 n, which of the following is true concerning its motioni9po:lfl+ vc 4quj : 1vhy16nq?

  Suppose a ball is thrown/lk :l+9d1 w6qecbfln straight up. Make a statement about the velocity and the acceleration when the ball reaches the hc lq+wb n6d1f/kl:l9e ighest point.

  Suppose a ball is thrown straigh:ikzur;u3nm 8o3ae9 y t up. What is its acceleration just before it rnumz3a 3o 8:u9rieyk ;eaches its highest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then falls/m 2* doa efpp(,b+moa to its initial height. Make a statement aboup, p*/d oa+2emo bm(fat the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then o(crxc q*h,jx5v mo4n:z3,wlh 6 jh r5falls to its initial height. Make a statement about the directionqho:rn,*35 cj5xm6cr,(vo x hj 4w hzl of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a st( t8nic 6lgte*atement concerning its acceleragt c*(it6e8 nltion.

  Suppose a skydiver jumps from a high-flyint: f1yyz6o 1gfg plane. What is her acceleration when she she 1g1o yy6tf:zfreaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identical seconvu )(vwwnr om,umj+:eu g4;9h d 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 ofowuuw (vge:)ur; m,4+ nmvhj 9 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, gp+nte-vn2k bbe;:ll i; 6t)9lr nmb .ball B is dropped from the same building. As time progreettr6gn elv2: nl;mpn.9bik -b;+l)bsses, the distance between them

  Ball A is dropped from the top of )mgyuwao o.-ott+4u4a building. One second later, ball B is droppe+uomt4u o.wog )-t4 yad from the same building. As time progresses, the difference in their speeds

  Two objects are thrown from+-pnkf qqj,i0-ax9xw the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when thqpi,+jkn af -wx-qx90 ey hit the street?

  A brick is dropped from the top of a building. A s /5pb.(if*jx:q0mu9ja g:tof za1 w yoecond brick is thrown straight down from the same building. They are released a(qi o o9tafxuy.0f/1:zjjm b5*pg:wat the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity in the +x axis. Thch89il6p6 , *ts ho)dd d6hvose position versus time g *il,hood vc98d)6dh66s tp hsraph of this object is

  An object is moving with constay8 rx8w)(-tr fngg+ki nt non-zero acceleration in the +x axis. The positiongk (8tgy)wr+ nfrxi-8 versus time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. The vzqhoi4*qew8v5z27n gr u 7,zxelocity versus time graph of thizz4rw, 28 ze h5quvoxg*77niqs object is

  An object is moving with constant non-zero acceleration in the +x axi8( 3stz;hygmzmtut w im54e:8 s. The velocity versus time sz5m:g 8my8uhm(t3 tz;4ei twgraph of this object is

  The slope of a position v n lfcp9od-tf p.-6+vi(:hsg uersus time graph gives

  The slope of a velocity versus time 24a ;4ev m.c)i+btklpio mh5mgraph gives

  The area under a curve in anwz1j yor,c3:bxr*jz4d:g h f0 acceleration versus time graph gives

  The area under a curve in c w+tkv*d;tm.a velocity versus time graph gives

  If the position versus time graph of an object is a hm .i)qgt bl**p3gfy 52f,lol forizontal line, the object tg lif2* p)ff5 ,*lymqlogb3.is

  If the position versus time graph of an object 39tn)lrq4vtg8vqsi 8 is a vertical line, the object is3l ) tvq8iqtvn9g4 rs8

  If the velocity versus time graph of an object is a horizontal line, the ob8mlc;i t:jl 6f8iw2nnject i6imw2l; fi ltnj nc:88s

  If the velocity versus time graph of an object is a straight line making anu *zhclq /s1,2e bau0w angle of a ql0usc*z/h be12u ,w30 degrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m sp7kjm-8ogqirj t p9 76outh. Find both the distance traveled and the magnitude of t8p7q7jk 9gjomit pr-6he displacement vector.

  A boat can move at 30 kmik tjr nm- swzcbe-c5 *.yx*ti1 33yy*/h in still water. How long will it take to move 12 km upstream in a river fcz.w 3ct-it*jy1*yn*mkse53 xr-bi ylowing 6.0 km/h?

  55 mi/h is how many m/f4 djkwoqbak9 x;2.q +s? (1 mi = 1609 m)

  What must be your average speed in order to z4r7 cvmli/ )coyz )y9travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. What i41 mb.vkf 0ykwhzm(lun-t1 t 8s the average speed of the ru(.v1yh- mt1 m0nktz b4ulf 8wknner in m/s?

  A car travels 90 km/h. How long does it take for it j nzbdb -fgm1+7f:(um to travel 400 km?

  A ly (light year) is the distance;nf/, : ej+jtflro d:;xws-b yn)hmb2 that light travels in one year. The speed of light is nr w:)jb:ot ef;d-;bf2myh jx+n/,ls $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 72 km/h alo1 4*c -m4tmzd.dh4bro3 f28kalaa euing a straight road and you look to the side for 4.0 s, how faoi amd taklde* b2z3-r.1a4 cu 44fm8hr do you travel during this inattentive period?

  If you run a complete loop around an outdoor ,e cybw*yc++6s ab, un.t7hl atrack (400 m), in 100 s, your average velocitsywny,*. l ea7bcc+hb6t,u+ ay is

  A polar bear starts at the North Pole. It travels 1.0 km south, then1qd5 p7nnjduha )mo1 8 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. What was the bear's average spu7a q 5)1n18 nohpjddmeed?

  A polar bear starts at the North Pole.ih2uf/jwjhx9-(4u a l It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to re-lwih(a 2 j/ujuxh49fturn 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 1,x -.yj9ezj qgb9 i6ksrss 6skn+2u2l 10 miles. It then starts to snow and you slow to 35 mi/h. You arrive home afte6g2nre2,9 z9yjil s+kxub-sq . sj6ksr driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 2ub:jp gt 65nwrt5cy, km/h. What is the average speed of the motorist for this trip j 5cgr6pn b:y,tuwt52?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is/hj ,vmxu2 ef4 her average speex um ,j2e/hvf4d for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and thenhjzzn 2,f w,d, at 250 mi/h north for 750 miles. What is the average spzjhnwz,,d f,2eed for the trip?

  In a 400-m relay race the - qy 1+e/3fu2jzvvdm panchorman (the person who runs the last 100 m) for team A can run 100 m in 9.8 s. His riva3yf+/-qz2 emuvpv j1 dl, 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 runner not lose the race?

  A car decelerates uniformly and comes t) pdbcsypcpfb85 j/:8o a stop after 13 s. The car's average velc:pb5yjs)c/f88 pd b pocity during deceleration was 42 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 1,ydyo2xhnat b8q*si d p5-d3/00 m/s to 160 m/s, at the average rate of d3 q i- pbxt,y/d58ydah2os*n $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate of jj6el 9(3mkxl $2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

  A cart starts from rest and acceleratea -em,wt7 0ob0f)dymlwbf47 ,p i*xvxs 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 accw9dhh/l1s jt5 elerationl/j w1t9h5h ds of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial 68ksj+he9om 4 jdjm3kvelocity of 1.8 m/s experiences a constant acceleration of o skekj9h684m3djjm + $3.7 \; m/s^2$. What is the cart's displacement during the first 8.0 s of its motion?

  A bullet moving horizontally to the righs-r5ob/7u1qs /ec zo ht (+x direction) with a speed of 260 m/s strikes a sandbag and penetrates a distance of 12.57 cm. W o7oe/zs/uc5qrh1b - shat is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircra1p uz1hpn 7ym9ft carrier. It reachp zy nu9m17hp1es 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 catapult?

  A car starting from rest moveuyq 34/vq kgktcno+,3s 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 a)5vjeh6b nzb0 wz 8kw/verage ackvwz6bwb j)e8znh5 0 /celeration?

  An object starts from *nfo-j :2t.eqmffw4v rest and undergoes uniform acceleration. During the first seconmof 2wf n jt:*eqv4.-fd it travels 1.4 m. How far will it travel during the third second?

  An object is moving in a straight line0. to6 5z (qefa/kxw6-qig asti skp23 with constant acceleration. Initially it is traveling at 1t6s 6we s.g2-q q i tkz/ai0x5opak3f(6 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates uniformly at4ooe,uv+/se4cgug i 6 jk.1av $3.0 \; m/s^2$. 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 decelerate rs4c7m q*pm:exj+q7 . w:mjtqmn-k-rat 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 at th:(p;: ks5olps(-x oftltjn . ee intersection starts ahead with a con;l( fs5kj (lpx- :pnoo.:ttse stant 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 m/s on the surface jt( d41qn xe*lb8j(mi of planet X where the *(tx lqemj1 jb4di 8n(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 v folz- b/;zvk-i+yd4k qjf30of 12 m/s on the surface of planet X where the acceleration due to gravitbvkz q+-i/l -4f 3oyv0fjzdk; y 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 surxgi/r+wd .x8yi 5 wd7x3gn(eeface of planet X where the accei/n.de( x yig5xre7wg+8w3xdleration 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 soam a-(9w/s qsq )ygi:peed of 14 m/s on the surface of planet X where the acceleration duewa g)y /-a9(qmis: qos 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 friend hol t2d1 my.d,poau(+dqxds a ruler between your fingers and releases it wittuqm +. xdoa(yd 2d1,phout warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 1 -t1r iz i-lrmda7v- crklx7k fo276:w9.6 m/s. What is its velocity after 3.07dto6v l 7r-ra-rkc- liw:k7zf1 m2xi0 s?

  A bullet shot straight up returns to its starting point in 16 s. What is the i ide 8+8:ax3yikmyn/fnitial speed of t kmiin8 eyda:/yf8x+3 he bullet?

  A ball is thrown straight up with a speed of+0xwo.seari g/6dbj 9 36.0 m/s. How long does it take to+go6ij bed/w.xsar 09 return to its starting point?

  A ball is thrown downward from the top of a building +hw.ht1(ht y vxtq v57with an initial speed of 22 m/sqh 5v.hwh1yxt 7tvt+( . It strikes the ground after 2.5 s. How high is the building?

  A ball is thrown straight up with a speed n.xh/ **vu1kon9jvpp u9 s-a gof 30 m/s. (only fill in numerical value igxp*/ah-9.nuo v 9*suk1 jvnpn 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 intos qeph1,r+h/ wb0wr0at kozxf ;:+ my; the air with a speed of 26.3 m/s. (use $g=10 \; m/s^2$, only fill in numerical value in the blank)
(a.) Calculate the time required for the ball to rise to its maximum height.  (数值)  $s$
(b.) Calculate the time for the ball to fall back to the height at which it was hit.  (数值)  $s$
(c.) Calculate the maximum height reached by the ball.  (数值)  $m$
(d.) Calculate the ball's speed 1 seconds later.  (数值)  $m/s$
(e.) Determine the time at which the ball pass a point 11 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 11.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocit 7x+* o(y h5xic(vp-evw qiw2iy at t = 1.0 s?

  In Fig. below, what is the+u/vkmqud32 wb(eq3 q velocity at t = 2.5 s?

  In Fig. below, what is the velocity cn ,n-cnj(v(yat t = 4.0 s?

  In Fig. below, what is the veloc-j+l9tz ul 6/gyat jaawg 1y56ity at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to 4.uw( 3u9supx 3q-g*eia0 s?

  In Fig. below, what is the average velocity from 0 to 6/npx +fgnoj7u5j is vif s7044.0 s?

  In Fig. below, what is the acceleration)u 3nllv(r2wl +gf ka3 at 1.0 s?

  In Fig. below, what is the acceleration at 3.01tqy-,3e23 0oz pfub 7nrzvnt s?

  In Fig. below, what is txh+ v bjfajn6)mm9 3vi q40.g7ej, gwyhe average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration d9y*fd 7 z.vmpfrom 0 to 8.0 s?

  In Fig. below, what is the displacement from n keysiyu2; e9x,f1fw ao0s/j0 ca 6,c0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|vewi6*w o e(vmmmhdwah7o q::,*locity}

  An object can have a varyins(ma:x ve4o/t g speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is positiv/wkf6j si n7haq, /hm;e.

  If one object has a greater s n3v+(:c onyv ,p6dkegpeed than a second object, the first must have a greater accelera k3 d6nvy+p,vnoec(:gtion.

  Two cars emerge side by side from a tunnel. Car A is travelingal9p/3wm-w 1h5dtmf5y8 cr rb 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 decreas)+. j 7u .rf9gxpikqcqes.

  A baseball player hits a foul ball straight up into the air. It leaves the ban+ 23 ft)waa gpduwf.+t with a speed of+afwu).gtnwd +a 32p f $120 \; km/h$. In the absence of air resistance, how fast will the ball be traveling when the catcher catches it?    $km/h$ (please only fill in numerical value in the blank)

  As a freely falling object speeds up, what is happening to its acceleration, j ett8c 98l:irj-mk*zu:t;wdhow does it change if air fk imr9-d8t8c zuj*:;wtejt: l riction is ignored?

  As a freely falling object speeds up, w(q +yo2vkdi+iivk5 7 nhat is happening to its acceleration, how does it change vni 5k 2+qvd(yko7ii+ if air friction CAN NOT be ignored?

  An object that is thrown vertically upwaeopg7m.6aoza6 l, 3 dsrd will return to its original position with the same speed as it had initially if air resistance is eomg alas6d, 6o 7p3z.negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration ad cz5x5i byl3*t the same time.

  An object can have nonzero velocity and zeriu,j;trv etb,nq,(0h1(-,pzx7 yqt mwg4kal o acceleration at the same time.

  An elevator moving from the second floor to the fifth floojuph/ s9.yc:ir making no stops along the way has zero acceleration all t9jp:yi.huc /she time.

  A rolling ball moves fror3rx9( udw2msm $x_1=3.2 \mathrm{~cm}$ to $x_2=-5.2 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ to $t_2=6.0 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.3 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.2 \mathrm{~s}$ is at $x_2=7.2 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a m33heyh79edg,zk-b * ana ahp-5 7qyoquarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 8.8 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its trainer in a straight line, movin1v c)2r:5 n3fp4v2boo w hpifvg 115 m away in 8.9 s. It then turns abruptly and gallops halfway backnp 45v3) 2f1v2rowiofv: bcph 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 from hu8-*bnzycv8tt5:ef$11 \; m/s$ to $24 \; m/s$ in 4.6 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 fromzznmqz 6sct9*x;4i0f $18 \; m/s$ to rest in a distance of 61 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speen+ 6xwmuca3;4b 9w 0fle msq/zd of $28 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.6 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst oute6oj63b4 ggv6d ) vyya of the blocks to essentially top speed abouto6agjgd y6)6e4vv 3 by $10.6 \; m/s$ in the first 13.0 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 uniw0m/; tlki wj8formly from a speed of $15 \; m/s$ to rest in 4.08 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves, 3 2vgw:ghqmq- ryys7 skid marks 92 m long on the highway. Assuming a deceleration ofys2g73 ,v:m -rwgyqh q $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trul0/ y, dtf 5gm9t+xbgick 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 cog . 1iv(pv36zr8l med/oiioj2 mplete the 10,000-m run in less than 30.0 min. After exactly 21r2d o(3e8g zlv . vpmij/6iio7.0 min, there are still 1100 m to go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$