Suppose that an objectgg 13u7rdoun8 v:qe s* travels from one point in space to another. Make a comparison between the displacement and the distance trvsdeu*8 rn:37qu gg1o aveled.

  When is the average velocity of an object equal to the instantaneo1 ityjh .lcr,;m0mum-us velocity?

  A new car manufacturer advertises that t p+b/v :fgfi*bheir car can go "from zero to sixty in 8 s". This is a description of*/ pivf bg+b:f

  An object moving in the +x axis experiences an aceoj+xoxfp x/ ) ;l)*qyu9tzo-celeration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling t ub/+x,m9fu i-z*x xlio the East (+x direction) begins to slow down as it approaches a traffic light. Make a statement concerning *xxu blm9i/ fx+u,i-zits acceleration.

  Suppose that a car traveling to the whuq.q feceq3946-l tt i;zl0oqnapj3 p0) d;West (-x direction) begins to slow down as it approaches a traffic light. Make a statement concerning03q w)n9 ih p t;f634uj.;aeqqll0dz eqt o-cp its acceleration.

  Suppose that an object is moving with a constant veloc7tk ezlt5*pkb76 *h rune,s .iity. Make a statement concees p * *6bt,uh75klnri.7 ektzrning its acceleration.

  If the velocity of an object is zero, does it mean tha jn7a0)ay lu8gt the acceleration is zero? Support your a7yl anu )g80ajnswer with an example.

  Can an object's velocity change direction when its acceleration is constant? Su3to -2w: x/yzgokjj m0pport your anstkjx3 ow-mgy: z2j0 /ower with an example.

  Suppose that an object is moving with const(1vurzs pk: vj;d9ofb6 m1d saw,69t tant acceleration. Make a statement concerning its motion wi jsm(;tp9 ftrd 6uozd ba61: 9,swvkv1th respect to time.

  Can an object have increasing speed while its a,1xq lms i ffu48vva:mwc21 p+cceleration is decreasing? Support your answer with an examplex8iuqp 1mvc24, :fslvmfa +w1.

  Suppose a can, after an initial kijn, hx7xuglk.hv;.z b)s .c, mck, moves up along a smooth hill of ice. Make a statement concerning its acceler;m,h ,.g zb vxc7x h.)usjk.lnation.

  Under what condition is average velocity equal to the average of the objec)z bk3j .2skryt's initial and f) .bk3 skjr2zyinal velocity?

  Objects A and B both start at rest. They both.lt .e)mz3km b 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 to that of object B). 3ltbemm .kz?

  Objects A and B both start fe,bj( w:r7j, +fnv m2z rmbju-rom rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. Wha, + mm (b: re-fjw2n,7vjbuzjrt is the distance traveled by object A compared to that of object B?

  When an object is released from rest and falls in the absence of friction, whic2cv. j0 ,vwbx+wxr1m/3p ehsfh of the fo2m0cwv/ eh 1v bwxx+,rf.pj 3sllowing is true concerning its motion?

  When an object is relet+dr-iv 2 j5ciased from rest and falls in the absence of friction, which of the following 25vd-c+r ii tjis true concerning its motion?

  Suppose a ball is thrown st cufg39m l hg+k.7iuilxa +-k5raight up. Make a statement about the velocity and the acceleration when the ball reaches the highekkh95 c aig u+l3il7mfx.+gu-st point.

  Suppose a ball is thrown straight up. What is its acceleration just before ranf8(mhq0k . it reaches its highest point 0(nkhrq 8f.am?

  Suppose a ball is thrown straight up, reaches a ma itm)ypoe21zcc32* gb 5ck*whximum height, then falls to its initial height. Make a statement about the direction of the velocetgc c1*2yb5 *pkcow3) 2 hzmiity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a max::x z+q0qtg 6lnb37ziehu :gjimum height, then falls to its initialg eg:: zx7jhti:q+ u qzn30lb6 height. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make+crzu 3 qf(u6t 8 4os(xg;mwjt a statement cou;j stq( g+wu86fmx(c 3t4zroncerning its acceleration.

  Suppose a skydiver jumps frb vif1r/ 8-jtp1z;4dj.j7y ,i( i gt:ajqdh mjom a high-flying plane. What is her acceleration when she she reaches z7;y8i1hgtj-jj.v,/fm qpja t4 (drd ji i1:b terminal velocity?

  A ball is thrown vertically upwar-yruqxv,b:4jh tg. 4ed-3pw krgt; 6s **mnfhd 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 second ball to that of the first ball? (Howhmxjq e *.6*;,--yhwp4:s tgtk rdn4ugrv b3f 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 dro(exm)xq+/h(cnz-o v epped from theev -oe)(/hczm(+q xxn same building. As time progresses, the distance between them

  Ball A is dropped from the top of a building. One s7.jz/(ax,i f+ykw inr econd later, ball B is dropped from the same builk r aj+7.izf,/ xwyi(nding. As time progresses, the difference in their speeds

  Two objects are thrown from the tyn,x-kztcp69u o li,c1.c/ t eop of a tall building. One is thrown up, and the other is thrlcc6 uc ,,ekt.iy9xz -/1onp town down, both with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top.bx m9ztc6lnaegj/ /vf/fx/9 of a building. A second brick is thrown straight down from the same building ezfn 6g xa.jt9/mxvfcl/9//b . They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving llz t (qo+d95k83od uuwith constant non-zero velocity in the +x axis. The position versus time graph of this object it(5oqkz93+d o dl 8uuls

  An object is moving with constant non-zero acceleration q (eiph .k3s6sin the +x axis. The position versus timep(hk. qs3 e6is graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. The veloci 2c7. ei jpfhzp81b1pqxq)i8sty versus time grab.q27px1 8 spii1e8czph j) fqph of this object is

  An object is moving with constant non-zero accelesyr 23vnscrp+9 .0o9lpy v wq7ration in the +x axis. The velocity versus time graph or +qo9c wsplrs0293 v7yynvp.f this object is

  The slope of a position versus time ,i uwv 5s85hfhgraph gives

  The slope of a velocity versus time graph3ct0 oh.rr 1iv gives

  The area under a curve in an anz5n5xep ;0uicceleration versus time graph gives

  The area under a curve in a velocity versus time graph gives/* hzw*e dyjr1

  If the position versus time graph of an or3-aa o q /x4tkvnj+c6bject is a horizontal line, the object i ra-ckj4t/o a3vxqn6 +s

  If the position versus time graph of an object is a vertical linujc -3kbcqxa2*k o ov eb-g +7p)i)h3re, the object is 73 a kb*r pj c+obk-uhigc))23q-eoxv

  If the velocity versus time graph of an o) tnngg 3owk)v4r x478 jwx/dxbject is a horizontal line, the object w/xk 4 dt7xgr)g vn)4xj8wn 3ois

  If the velocity versus time graph of an objectg t35v 4m:)dozq. p,woh*djbk is a straight line making an angle of 30 degrees with the time axis, the o w. jb53*o q,hvt)g:om4kddzpbject is

  An object moves 15.0 m north and then 11.0 m south. Find both;1mu kfw7zbwp. )/kya the distance traveled and the magnitude of the displacement vzfw pa.w/ku;k 7mb 1)yector.

  A boat can move at 30 km/h in still water. How long will ycmah-kngm7zm3, d(v1t99fq it take to move 12 km upstrea3 mc9hdk71mz mgq(t-afv ,9ynm in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 1-le i;tdgt ;;xwof *bmi = 1609 m)

  What must be your average speed in order to travel 350 fkmg;p0w3.u g4mxwfy p + z7(rkm in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 yg05k3 :0wxobh pa+p4-c jq7 1 ghdlqpmin. What is the average speed of qhg+kh4ld1:apo x37-qp cgw b0yj05pthe runner in m/s?

  A car travels 90 km/h. How long does itj.f:8rmz3 y ;e, hrp( mau5whyi13xdy take for it to travel 400 km?

  A ly (light year) is h,blb,0utta ;rcr m/ 3the distance that light travels in one year. The speed of light ilr,au/h;03,b rmcb tt s $3.00 \times 10^8 \; m/s$. How many miles are there in a light year? (1 mi = 1609 m, 1 yr = 365 d.)

  If you are driving 7dcs z 12s4 .ocmh32mur2 km/h along a straight road and you look to the side for 4.0 s, how far do you h. u1rsm4c32m2ds czo travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s,lld5;,mqrcff6* e q m3l.py2o your average velocity i y*o,rf5l6eq. ;pl dlm2fq3 cms

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km 1 zd2 7nwn+h0alsm(2n*z mb+ cqj5wxz east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes w 7z+5n (sq wnbnc*22d mamz1j+l0hzx 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0qv /5e(k2psmgw i;f 7a 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 wam57 ;wkvfg i(a/s e2pqs the bear's average velocity?

  You are driving home on a weekend from school at lh8p3-e4o)ep8 0 dvjn .lcdzx 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometown 34h0oe88c n-lz dldx pp.jv)efrom school?

  A motorist travels 160 km at 80 km/h qu7gg9 6u;bh rand 160 km at 100 km/h. What is the average speed u6q7ggh b ru;9of the motorist for this trip?

  A motorist travels for 3.0 h1c lc ss 9yqafpc0mjf1.d42( y at 80 km/h and 2.0 h at 100 km/h. What is her average speed for the9sfqmy11jls faycc0 2c (4dp. trip?

  An airplane travels at 300 mus84b3nj+,w8z:kwa saf2bd xkq7st /i/h south for 2.00 h and then at 250 mi/h north for 750 miles s8zb bsn4kt a8kxw uqw/s:d37,fj a2+. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs ;wk /ky n /h8d zq,n.5hfaou8tthe last 100 m) for team A can run 100 m in 9.8 s. His rival, the anch y/f,anq8 t.8od whk;u/n 5hkzorman 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 uniform;upw/x6aue. ( fbw5 4v/fhx8sw (k jxhly and comes to a stop after 9 s. The car's average velocity during deceleratio/u/w x584x. h6wsx(fe jpv;hkbufw( an was 49 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed fromd+ .h9l*ykujyme4sa1)v jg7 q 100 m/s to 160 m/s, at the average rate of )j4dk hyys avuj9+q*1.7 gelm$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at th m94uf-h rswk dbi86)ve 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 accete(h)3z9l a 2eo9sex jlerates 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 constan*+ wpj4( zdithchl w--t acceleration o *j-i-wt+4lczpdh w( hf $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 6.7 m/s expe 5byhrrho*3,stw.: 7 dvh.yj7s wpjb 3riences a constant acceleration ofwv3y yh.s,*j b brh73o:htj w.s5dr 7p $1.4 \; m/s^2$. What is the cart's displacement during the first 6.3 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed + cmo9nhr:2 lwof 245 m/s strikes a sandbag and penetrates a distance of 86.79 cm. What is the:lhw ro 2mn9+c average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft ca/m .qwrdb2 ul;rrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the a. rb2qdl m;w/ucceleration is constant, what is the length of the catapult?

  A car starting from rest moves wi/iz cor5l* 8ix4l thn+th 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 ave cw tvnhmgm b0m)z--3)rage accelw-)mhcm-t 0 zng 3vb)meration?

  An object starts from rest and undergoes un3e,tx ,4c sdiviform acceleration. During the first second it travels 5.84cd,vetxs 3i , m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. * i4i:p7e1k6d5lnzrb e*pnxa Initially it e4eaz6b:nii* ln 1k5x *r dp7pis traveling at 16 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 andosj8*pd8 /v,i uv1c dh 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 canygt*2n,syyl2k f vejaww7 732 decelerate at about $5.0 \; m/s^2$ when braking. Suppose a car is initially traveling at 55 mi/h.
(a.) How much time does it take the car to stop?    $s$ (only input numerical values)
(b.) What is the stopping distance?    $m$ ((only input numerical values)

  At the instant a traffic light tu vv4(utqb;e 97vel xi7rns green, a car that has been waiting at the intersection starts ahead wu b4ve9evi( lq;7vxt 7ith 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 upward with a speed of 12 m/s on the surface of pla0.uvude:rz*e5 ( v gndnet X where the acceleration due to gravityr(e5deu0 d.*nv zv:gu 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/9ip7 oaem(3sk s on the surface of planet X where the acceleration due to gravity i9a i(sop3mek7 s $1.5 \; m/s^2$. 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. s/cs47 xs8qaiz6v ous,)rtg the surface of planet X where the acceleration q 6s /,cs)ozi7. sgaxsuvt8r4due 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 1jf -us9z qu5bovy96qupward with a speed of 14 m/s on the surface of planet X where the acceleqsuuq- 6z51y ovf9 bj9ration 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 friend holds a )k:hi /;afs0wjxcd j i: ;8prdruler between your fingers and releases it without warning, how far can you expect the ruler to fall8kiawi/ ;s; f:hddj0p)r: xcj before you catch it?

  A ball is thrown upward at a velocity of 19.6 0s3 mu/t5cxgbm/s. What is its velocity after 3.00bg0u tx3s5m c/ s?

  A bullet shot straight up returns to its s7kyc -rj g3, zy,73lztn 3mitdne5e.o tarting point in 11 s. What is the initi 3jl7ce,oidretm73y, t 5n-zgzkyn 3.al speed of the bullet?

  A ball is thrown straight up6uygb1; e a.sn with a speed of 36.0 m/s. How long does it take to return to ib.;y 1uag6e snts starting point?

  A ball is thrown downward from the top of a building with an initi4vf io zx5,q/zal speed of 10 m/s. It strikes th5v ifzxq,z/o4 e ground after 3.4 s. How high is the building?

  A ball is thrown straight up with a speed of 30 n3)e sy2e /n 7hltvl3rm/s. (only fill in numerical value in the blank)n vhs/lt 3ee3 7ln2yrs)
(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 speed of 26.5 eim28uv:;dmv9l dc j1 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 b*uxmo 77y v9pat t = 1.0 s?

  In Fig. below, what is the v7lit;k mh 5f lr*z1q4delocity at t = 2.5 s?

  In Fig. below, what is the velocity at t = 4.q 9eqdp/:fv /;+ blzrc0 s?

  In Fig. below, what is the velocity at t = 5ha*/j +bprayl6e,w e5 .5 s?

  In Fig. below, what 9)so s7zw 5xjrc3si)l p*brn-is the average velocity from 0 to 4.0 s?

  In Fig. below, what ifuq gd6) g5y 5x+snxl z2b5q/es the average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration atk .)ia4) wkzbg;l+hbm 1.0 s?

  In Fig. below, what is th: gwam bcu9f+ja.5(sjsy( som gr6u ,2e acceleration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 to 5.0 x0.w 2 o.mrbhos?

  In Fig. below, what is the average accel p8or88l 15iu-7uow pswryph:eration from 0 to 8.0 s?

  In Fig. below, what is the displacement f(0kl*o , wc:b eoelta eo3;u4brom 0 to 8.0 s?

Does a car speedometer measure speed, m0.ixz,)hc- tddqyg, velocity? {speed|velocity}

  An object can have a varying speed if its velocity is d4tn t.2ws : litqe8k9constant.

  The velocity of an object can be negative;jk7eb 3rt dac(- o( sa8lo;wh when its acceleration is positive.

  If one object has a greater speed than a second object, the fqy2l/kqg s3my g 4ot42irst must have a greater acqo/yy2 gl3 4q mk24stgceleration.

  Two cars emerge side by sidemig)9lbso pu;fu9k7( /(rfip 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 speedby t5ep) to(o2u*fk e/w gr.+j as its acceleration decreases.

  A baseball player hits a foul ball sl9dm/ togbllfq 2138i*h+pudtraight up into the air. It leaves the bat with a speed folp l1l92+ht 3ibdd*mu /8qgof $120 \; km/h$. 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 v3 2)kxrzfx(l is happening to its acceleration, how does it change if ) lrk3vx( fzx2air friction is ignored?

  As a freely falling object speeds/q(ztggvg, a145lc ft up, what is happening to its acceleration, how does it change if air friction CAN NOT,1att v zg5/gcql(g4f be ignored?

  An object that is thrown ,ublt3*ew62ga c ao9o vertically upward will return to its original position with the same *6,2 wbgc uotoel 3a9aspeed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleratio czux0pzg+) )*rzn;3 +vuo rshn at the same time.

  An object can have nonzero velocity and zero acceleration 3u 0uwf2sz 6gxat the same time.

  An elevator moving f+ovh-:cu 3m0f.bss)ky bnj(4np gsr9 rom the second floor to the fifth floor making no stops alon f4vr-kmu3j )+ nbpgsosb9. nc0y:hs(g the way has zero acceleration all the time.

  A rolling ball movesy j+rz,f c/zf9 from $x_1=2.9 \mathrm{~cm}$ to $x_2=-7.9 \mathrm{~cm}$ during the time from $t_1=1.1 \mathrm{~s}$ to $t_2=5.1 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.8 \mathrm{~s}$ is at $x_1=2.2 \mathrm{~cm}$ and at $t_2=3.2 \mathrm{~s}$ is at $x_2=7.8 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps aroundj;k;pk h 6m9)5zch wfz a quarter-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 traig9vg) /z+ cr:h 4jnjjdner in a straight line, moving 109 m away in 12.7 s. It then turns abrjzh vjjgd+ :4 cn9)/gruptly and gallops halfway back in 4.7 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 fro2ehu+cy azj ovz*1 49gm $11 \; m/s$ to $25 \; m/s$ in 5.3 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 fromuav,6 77g2g3mxezl oj $20 \; m/s$ to rest in a distance of 81 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a z q5tqxa-:ll- vh7nh 6 w-v7awspeed of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.2 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the b(b9;ovs6vvqch **usq m ;p: /np tcw0ptwl,:plocks to essentially top speed about*0:l p ,o :w(cnvpvvqtb sq6*m/;;pcw u9hp st $10.3 \; m/s$ in the first 10.5 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 speed opfs)-91l w dnwf $20 \; m/s$ to rest in 5.78 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a c ykrtsnyv ri. b1;(6/nar leaves skid marks 92 m long on the highway. Assuming a deceleratt.y6b/nvn;1yki(rsr ion of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a tr/b-pivit23f+ yu gv,3gq+v 0*p inwiq uck 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 10,000-m rul5grn j/ ,ugagm..n8cdm+mvst/2*zyh r p*7nn in less than 30.0 min. After exactly 27.0 min, there 5 gu. rz2pmycmmln/t* gga,dn nj7r+*8vh/.s 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?    $s$