Suppose that an object travels from one point in space to another. Make a compady /:mpe4fn)l rison between the displacement and the dis4)y/mf denlp: tance traveled.

  When is the average velocity of an object equal to thl;skor7cn/h 3 e instantaneous velocity?

  A new car manufacturer advertises that r j. d 4rfy.k9 j-tow0fhssw5 p+oi.q7their car can go "from zero to sixty in 8 s". This is awpsd.o9qw0jf t 4hk5 i r+yo-..7rjfs description of

  An object moving in the +;ao zw6m,a6pp y zzk+,x axis experiences 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 slow down h1rvc dv+c faj h (o;x+4ri+4.c jah/jas it approaches a traffic light. Make a statement concernin4(+rc/;j+ .rdxvcjvaoh4hac1+ hf ijg its acceleration.

  Suppose that a car traveling to the West (-x direction) begi.v,ivcp1 xym3u7/ x+gci+vq p ns to slow down as it approaches x7qu v, pg13ci+vi pmv/xyc.+a traffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Makebbe6)zt)av 9g a statement concerning its accelerzbtg aeb6)9)v ation.

  If the velocity of an object is zero, doesac,o/b7i 3 7k-fcnqu mba b:13dw9sli it mean that the acceleration is zero? Support your answer with an exam/k3m q do 9ub1swcab-7in3cl: fab7i,ple.

  Can an object's velocity change direction9tcz, .czn,s q when its acceleration is constant? Support your answer with an example.z9n.cs ,zqc,t

  Suppose that an object is moving with constant acceleration. Make a statement 9frsi+ ewt8-3sp*(d okweyj + concerning its motion w*(skfwe9yo3+j-ei 8 rtd pw+sith respect to time.

  Can an object have increasing speed while its accele u-jmfo.g ir41ration is decreasing? Support your answer with ar 4i-1ujfo.gm n example.

  Suppose a can, after an initia1 nk+y zdaz6bzv-3q h0l kick, moves up along a smooth hill of ice. Make a staq -ny6zbzh3z +d10a vktement concerning its acceleration.

  Under what condition is average velocity equal to tx hou s+.-wnel 6,8nsthe average of the object's initial and final velocit +nwsnuhlot68,s ex-.y?

  Objects A and B both start at rest. They both accelerate at the saz5bsg rjw3z; 2l/* xf(fiiuc23ys u6bme rate. However, objecu fj (6u*fr ix;2 ys3/2bsicgz3z5wlb t 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 accx1,vf(nsfad q(w(b :h elerate at the same rate. However, object A accelerates for twice t ,(q(x:fvbdfn aswh1(he time as object B. What is the distance traveled by object A compared to that of object B?

  When an object is released from rest and fjcu(tp/lf * sxhzt0w8x+f;lu 3j 5vf-alls in the absence of friction, which of the following i/530j uphzc ws+fxtxu*f (tlv;f -j8ls true concerning its motion?

  When an object is released from rest and falls in the absence of fricti6.uc ilzts/7kpb 5w,non, which of the l zpbn76.istcu /w5,k following is true concerning its motion?

  Suppose a ball is thrown strlu9;rh9f 2j;m dnctw;fcd 54eaight up. Make a statement about the velocity and the acceler2 hmj f ;9luwnd9 4;5der;tcfcation when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just befosf5se57tl -sdbo *vf;re it reaches i s5sft;ev*o5d7f l bs-ts highest point?

  Suppose a ball is thrown straight up, reaches a maximum height, then f 3.r6v s0 yx 7wqeqfqzrij.+l)alls to its initial height. Make a staf z)xql7s0q3e.j6 +v qiw.yrrtement about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a gqh p*64wa i9welv2q 0si7wg 8maximum height, then falls to its initial height. Make a statement about the directi*74qw62aw0 8 wgivs i ph9elqgon of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown d : j80kdc uy8 w6rxxl8,qqw1jqownward in the absence of air resistance. Make a statement conce8rq8186 l0xjwxdwu qy:kqj, crning its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her acceleration mo7at6xtwew q7 fn)(,when she she reac em)q7n (t,ftaxw76owhes terminal velocity?

  A ball is thrown vertically upward with a speed v. An ipe ,z m tqy;exgkwk1313+k+eddentical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the secoekyq1 m tk 3z;g+1, +ekp3dwexnd 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( 91-iwac-d:: iiv2gosebxwy v u;j+i dropped from the same building. As time progresses, the distance betw : i;(i2 u1oijwes x-gv+:9cdvbayw-i een them

  Ball A is dropped from the top of a bld(7oo 5jw .rouilding. One second later, ball B is dropped flrodojo ( 5.7wrom the same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top ofto ( 2fn./eqtixt3q,v a tall building. One is thrown up, and the other is thrown down, both wi.,qo3f (itqnve /t 2xtth the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second br-u 5 fa f v68xq*he1oi9exjro8ick is thrown straight down from the saf*u1xqo8 o6- e 5ar9vfx j8iheme building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero txx c.-e*5 6wrpvsfz/velocity in the +x axis. The position versus time grat.vzwrx c-/5 x*sfpe 6ph of this object is

  An object is moving with constant non-zero accq:nlx vy,4 lz(eleration in the +x axis. The position versus time graphzynqx (:vl,l4 of this object is

  An object is moving with constant non-l8q .ruv0r ce0zero velocity in the +x axis. The velocity v e800rvlcqru. ersus time graph of this object is

  An object is moving with constant non-zero acceleration 8r* e ppc(g eb4okt+5ba7 ghk*in the +x axis. The velocity versus time e g*p *h4b ep8kc(ob+ga57krtgraph of this object is

  The slope of a position versus time graph uepp 6mimvwi*w. 3 q81gives

  The slope of a velocity versu8* m0n(i pf8 qnujzs z;xqx9yjvn620vs time graph gives

  The area under a curve in an accelz:n pmsskp+;yo.6* r3pzro4cb + yfi8eration versus time graph gives

  The area under a curve in a velocity versus time graph gim264t btw9q cgves

  If the position versus time graph of an object is a horizontalrda0.q m)zqrl)kam5 2 line, the object )mmzq)dqk 5raa0.r l 2is

  If the position versus time graph of an object isizbe ag1(;c:p+jxx+tn :c k (y a vertical line, the object isej;b :1tixyz(ck(xa :cpg++ n

  If the velocity versus time graph 6 /rkhhno70dez(z)ja (ddl)d v4fo 1nof an object is a horizontal line, the object isnz )1efjv/d0( hoo)d4 d nlha( 7kr6zd

  If the velocity versus time graph of an object is a straight li v v1n+r -:hfef)ilgjglsqu; k06o4 v-ne making an angle of 30 degrees with the time axis, the object is1)+ofvnkr0fvv-usllqg 4 - ;g6h:jie

  An object moves 15.0 m north and then 11.0 m south. Find both the distanc2n:e exlc1iozn vx1rx .- aw)bore -t*a)y47fe travele- 11y- *4inzrfe7ebroaot):x lxn xca. v2e)wd and the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will il)8 7wt5txlaqt take to move 12 km upstream in a river flowing 6.0 km/xqwt )58allt7 h?

  55 mi/h is how many m/s? ujh3eb ,ln: 0t(1 mi = 1609 m)

  What must be your average speed in order to travel 350 ym;2qf5ai e:skm in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hourwl6-pe1)7 nlra 9-nf +gsa etcs and 57 min. What is the average speed of the ru9gn awlar+fn1- 7 )6-lpteecsnner in m/s?

  A car travels 90 km/h. How long does it /6i r: duw0l:-td qnzftake for it to travel 400 km?

  A ly (light year) is the distance that light travels in one yewte;okrm 9u)1ar. The speed of light i;mu1)twkro e9s $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 72 kghk8xaa )f -h,- -lhfz,/tw y.7jffxem/h along a straight road and you look to the side for 4.0 s, how far do you travel durih,x,z ) wa-thf7ff-al.gy /e8k -hjf xng this inattentive period?

  If you run a complete loop around an outdoor track) 427r . ns,4uimi,xigdx arbs (400 m), in 100 s, your average velo )bxi.xir r,nag27,4du im4s scity is

  A polar bear starts at the North Pole. It travels 1.0 km sob:m1i.n by.sb uth, then 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 speed?b.n my.s 1b:bi

  A polar bear starts -l i9 gno-art 85mu-zgat 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 trip takes 45 min. What w-lg 9uo5 -i8 zm-agntras the bear's average velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles. It (:xo0x p kup9wthen starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. xupwxk9 o 0p:(How far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 16/1u ,tfe6cjpz)nq/n nh9n2 ms0 km at 100 km/h. What is the average n6mt9pj)2fu nnnq1 ,s /e/hzcspeed of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h ari0q0gtb1k:5 1v1: phijftue* xi0ys t 100 km/h. What is her averaget11:b*r10 ki0xuq: 5y pgsjih0ef ivt speed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at dondk wnfa yi 6zwy,:opir 2l;m 598)9250 mi/h north for 750 miles. What is the average speekfdmip;yd anr9)z ,lw6oio82wn95 y:d for the trip?

  In a 400-m relay race the an,iernuoqm6:tq 3yqsfebxn0gs8 8* k x,f .c +)chorman (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 is the largest lead the team B fu:q,n6,)eqmcy sr o q+n0ite38 ks8 x*bx.fg 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 14 s. The car's *uy itid.+)pnaverage velocity during deceleration was 56 km/h. What was the car's deceleration i pdt*)n.yu+iwhile slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, 3ixr0mbhmml4r8m q (7at the average rate of mm8x0h73qi m(rlrb4m$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acce t+4 f2g1hpbf yp+0jqwlerates 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 a l)3,ixfj0e land accelerates 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 nfs*ak , ,dc1 5bpwi0rmu5n)(nexa9s 10 s. It then speeds up with a constant acceleratioebd*n5)u,9a kws i,fas (n15r mcn p0xn of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 6.5 m/s experiences a constant acceleration 5+ c/vlu;dub molu+; uv/5db mcf $3.3 \; m/s^2$. What is the cart's displacement during the first 5.2 s of its motion?

  A bullet moving horizontally to thelx 5.n z qnpkt8-ljr*- right (+x direction) with a speed of 557 m/s strikes a s8lt p*r.-ql 5-xnzknj andbag and penetrates a distance of 63.57 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is b3 i2aio e7 hgfiv.v9xh;rzjl 1 aw-/8launched 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 acceleriwh1hl3fj.xv7ar/ vz; ea-2 og9ibi 8 ation is constant, what is the length of the catapult?

  A car starting from rest move5b 65di 0a / gtv-5 (jdsfv*is1ot).h srhjpkks 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 ofcqmhdh 6jh1 ln-w*k8 ( 200 m. What is its average acceleration hjqd1h-6wcmk nl*(8h?

  An object starts from resty*kko5 6l3tj bi/rfn 79 uwwb- and undergoes uniform acceleration. During the first second it travel6n fkwu9t l57-b3 k/io*y wrjbs 5.0 m. How far will it travel during the third second?

  An object is moving in a straight line withvtg 984f)hqoz 8wc; xl constant acceleration. Initially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time84 9oqvz8)h tflwg;xc?

  A car starts from rest and accelerates unifu3htmw.4(px f ormly 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 cb+ia,brq 81cg6oe ;mxddo 23ate 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 gree 4qu8k f.nb:qjn, a car that has been waiting at the intersection starts ahead with a constu:qqf b.8nj k4ant 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 gkrt5t,oi.ego jg g3 ro0o 3e3c429gp m/s on the surface of planet X where the acceleration due to gravi4ip r3ertgoto,og gco5k20gj3 9 e3g. ty is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with a speed of 12 m/s on the surface of planet X wz5 s:6wjgsg6where zjgw :65 sgws6the 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 sulp;do i b:b:)brface of planet X where )il:p bdb;b:othe acceleration 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 surf 7qa o axq 016p-ljqhx2+tuef*ace of planet X where the acceleration dao60e l*+tq- qh2pxuxf7 jaq1ue to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usually h1t:. uyme5ivgreater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how fayivu .h:1em t5r can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. , t /rr71akorp:gi5htWhat is its velocity after 3.00gtr5ip,7 koh: ar 1rt/ s?

  A bullet shot straight up returns to its starting point in kk6xi x1bhu7 -11 s. What is the initial sxhi6k7xk - b1upeed of the bullet?

  A ball is thrown straight ug8: w3) .j3gb b3mthw( lzubeqp with a speed of 36.0 m/s. How long does it take to return to its starting poig ebb8:3tlghw)j.b33 (u qzmwnt?

  A ball is thrown downwzlhxctbc1vs0 ,7r3 8rard from the top of a building with an initial speed of 21 m/s. It strikes the grounhv70r13xr8 tcs,zcl b d after 2.3 s. How high is the building?

  A ball is thrown straight up witwi d:ya 3+9zxq+s1ho ch a speed of 30 m/s. (only fill in numerical valihawx9 o:+3zydc+ 1sque in the blanks)
(a.) How long does it take the ball to reach the maximum height?    $s$
(b.) What is the maximum height reached by the ball?    $m$
(c.) What is its speed after 4.2 s?    $m/s$

  A foul ball is hit straight up into the air with a 8aho 4)1cx;ddm s7pbkspeed of 35.0 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 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 +gdkzs-zf:ow t s4wg4u :e 2g+velocity at t = 1.0 s?

  In Fig. below, what is the v9p0bhcju k, zazch-, 0elocity at t = 2.5 s?

  In Fig. below, what is the velv3e(lo 3(f fhjzz)5e3g9p gp mocity at t = 4.0 s?

  In Fig. below, what is the velocity at t =-s-*cm rs4;b f4 cli(l hf3bwd 5.5 s?

  In Fig. below, what is elkt ;zzvlt c)2s;;r5 the average velocity from 0 to 4.0 s?

  In Fig. below, what is/pr22uf kp ojl* .vmy) the average velocity from 0 to 6.0 s?

  In Fig. below, what is thlkc1u af)p k 9kwnv.6zv/ar* 7e acceleration at 1.0 s?

  In Fig. below, what is the acc:cpd 6fil1m7weleration at 3.0 s?

  In Fig. below, what is the average accelerationw.:hq3y s)6cqnhfv1wzw 0 :eh from 0 to 5.0 s?

  In Fig. below, what is the averaot(9n1 * jfc pc)b:zr tv-u8cfge acceleration from 0 to 8.0 s?

  In Fig. below, what is the dwhhx nf8h9i*5 8 rb-kcisplacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|velocityy n3xnapm0;cz nxf 54i1/k8wo}

  An object can have a varying0 pqn*;; l5xp zgxchuyff- z/* speed if its velocity is constant.

  The velocity of an object can be negative when its acceleratu 1l,e+4xxbz9 hwl3yvion is positive.

  If one object has a greater spe1 z*ln 9,pxjl1eyk0eled than a second object, the first must have a gre1 1lle0e k,xnjl*z py9ater acceleration.

  Two cars emerge side by side from a w 4:m f4:lp26xxttvcv 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 acceleratio 1vl1nz(u+gqjj38qvi,xe c6 xn decreases.

  A baseball player hits a foul balj0 gb.jq9b s.e(xb)a14clmp pl straight up into the air. It leaves the bat with a speed o b.c me)xjjb4 0ba9(spgpq.1lf $120 \; km/h$. 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 speedt-yp28 . vgh dl-pnhr;r n+ 4-*zqubrms up, what is happening to its acceleration, how does it change if ry -npmn 4b2rltdgu.h* h;+ zvp-8- rqair friction is ignored?

  As a freely falling object speeds up, what is 4l opk 2yfc8mc64i) :m,qmueh happening to its acceleration, how does h)p cm 4:km,f 48 eq2oium6lcyit change if air friction CAN NOT be ignored?

  An object that is thrown vertx5kxdmy6(a skgc: * w-ically upward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be alte:kma (gwk5csd-x* 6yxred?

  An object can have zero velocity and nonzed 9w e,dri.(yuro acceleration at the same time.

  An object can have nonzero velocity and zero acceleratix/, vhdd it8 hya/kh89az2a7e on at the same time.

  An elevator moving from the second floort 6ji cpl/ya45 to the fifth floor making no stops along the way has zero acceleration ally 5/ litp4ac6j the time.

  A rolling ball moves fromjy( 0n iz22p uy;b a8qz(djky, $x_1=2.5 \mathrm{~cm}$ to $x_2=-7.4 \mathrm{~cm}$ during the time from $t_1=1.3 \mathrm{~s}$ to $t_2=5.2 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.9 \mathrm{~s}$ is at $x_1=2.6 \mathrm{~cm}$ and at $t_2=3.5 \mathrm{~s}$ is at $x_2=8.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps abd o66(q 3wwchround a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.1 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 w ib4a+2ww5ha;a hp v,a straight line, moving 94 m away in 12.5 s. It then turns abruptly and gallops halfway b4 ;i2aaw+w wha5, vpbhack 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 fr:rknonhvrh+ *9w// lc tfg/alvd,vo z.48n / jom $12 \; m/s$ to $23 \; m/s$ in 5.2 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 fromty 5c rj /9.;nfq 6rimjedk27h $16 \; m/s$ to rest in a distance of 78 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a /6p udfj-ob1zxulh5ujvz 64:speed of $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.1 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top speed abov (,xbll f;mq ks4j62yut 2y blm;jv,6 (sfxlkq4$11.5 \; m/s$ in the first 11.4 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 i7q p6tr9p+ puo7n7cn6rf /j+amat 6g speed of $18 \; m/s$ to rest in 4.35 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 9po6c,mym pcp)hwg 0f);r,9jqhq 4 ph;2 m long on the highway. Assuming a dece 0p,c h6 hrcofp9j,gm4p p);; )ywqmqhleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goin/: jcjx--n eet)xr(qsg $25 \; m/s$ 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 r3q1 tne0azmo5njym 6b+u.y1 nun in less than 30.0 min. After exactly 27.0 zbno eqn+y5umj63.a0yn m11tmin, 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?    $s$