Suppose that an objec2dq pihafu 7a)3m6qp7t travels from one point in space to another. Make a comparison id2hu 3q mq) fpa6pa77between the displacement and the distance traveled.

  When is the average velocity of an vhp85i *a/ym)pchxh 6object equal to the instantaneous velocity?

  A new car manufacturer advertises that their ca zres/y,2clkp 7af:+e r can go "from zero to sixty in 8 s". This is a descl rf: seap+7y, ek/cz2ription of

  An object moving in the +x axis experiencebd 116 5;1ju 3g3kkemdajmmqws an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x directionejif7lcvbm r6d fr2:zp zu2 ch5498n,) begins to slow down as it approaches a traffic light. Make a statement concerning its accelerationn76 25,devf89j: b upcmzrfrz2 hil4 c.

  Suppose that a car traveling to kogjn/0*1 mi tthe West (-x direction) begins to slow down as it approaches a tokm0 */ inj1tgraffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statemen- orjpf9 yzdx0y 2t(r(t concerning its accelera( ( 0rpjrdz 2-9ofxtyytion.

  If the velocity of an obsdwg k :eoj eyd23/w*4ject is zero, does it mean that the acceleration is zero? Support your answer with an :e32kw wsjy/de* odg4 example.

  Can an object's velocity change dire,7h:;wnoafd k ction when its acceleration is constant? Support your answer with an exampk7ad: o;hn ,wfle.

  Suppose that an object is moving with constant acceleration. Mq3h gbwi7xs c 9:(gbt*gkg/ *iake a statement concerning its motion with*t qch wgbs:*/g3 big9i g(kx7 respect to time.

  Can an object have increasing speed while itshy* ,v qrb13;owdf8tu acceleration is decreasing? Support yot y3wo q;uh*rf1d8vb,ur answer with an example.

  Suppose a can, after an initial kick, moves up along a hyvqh )/q,7kzp ::aozsmooth hill of ice. Make a statement concerning ita h ,y)z/q :hpvk7:zqos acceleration.

  Under what condition is average velocity equal to the averazwsmegxqeh n:i1q/ n,087 ljc9pm99tge of the object's initial and final8ec z9pi jn0 l,m/1wqxgmt:eh7q n9s9 velocity?

  Objects A and B both start at rest. They both d(c-* + okckxfdgw4 6gaccelerate at the same rate. However, object A accelerates for twcfgkdgk*xd 4- (+o6cwice 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 at the same ratehvv b)8gw1kb) . However, object A accelerates for twice the time as object B. What is the distance traveled bbh 1w)b vg8kv)y object A compared to that of object B?

  When an object is released from res6rkna *(pe+xxt and falls in the absence of friction, which of the following is truepxx6+(* ank er concerning its motion?

  When an object is released from rest and fall2ni-pk au t+:sl95 gzks in the absence of friction, which of the following is true concerning its mo:2 auz k-gin+tsl95 pktion?

  Suppose a ball is thrown straight up. Make a statement7m/p5k k i6tvf about the velocity and the acceleration when the ball reac67/mvtkk5p fihes the highest point.

  Suppose a ball is thrownad qoz0e;4i ti*y ip.8 straight up. What is its acceleration just before it reaches its highest p t.;zyiod i40qep8*aioint?

  Suppose a ball is thrown straight up,q/b fnhn,c w:q()l5py d td-s; reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity qnnwy,/qblspf 5d:)ht; (c -dand acceleration as the ball is going up.

  A ball is thrown straight 5rq7gb*g2ox2g 5:en ds 6wqorqu, 68snd(gm qup, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming down.qe, gdg6 o5wn bmq qrxs26qgdus*or:g82 n (75

  Suppose a ball is thrown downward in the 0qvo4f sn*ztnwe4q* 7y+x q4jabsence of air resistance. Make a statement concerning its accelerati+n*fj tsoqe*0 44zwqxv7q4nyon.

  Suppose a skydiver jumps from a high-flying plaj *ey )qalr +i-aia;1xne. What is her acceleration when she she rel;jiqyia reax *-+ 1)aaches terminal velocity?

  A ball is thrown vertically upward with a spee,drnrlz0..fz3 4rmupd v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximu3z,. rp.zdnlu0m rr4fm 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 o szahr1 c,w1ox1d77uB is dropped from the same building. As time progresses, the distance between7au 1oxc1hwd7z1 s, or them

  Ball A is dropped from the top of a bux9ici.gxyiq* j:a6* rilding. One second later, ball B is dropped from the same building. As time progressesyr ii9ci q **a6xg.:jx, the difference in their speeds

  Two objects are thrown from the top of a tall building.f v:x.g9 wamgf5:t1 sw One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the street1mgfg:twv 5 9asf .:xw?

  A brick is dropped from the top of a building. A sej2 pg1-7nl: h 3a*pxyz4wpalmcond brick is thrown straight down from the same building. They arzgnm 1*pwp2a-lpya x3 l 4h:7je released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with ip ;g,cp-eht 7f xrg,+constant non-zero velocity in the +x axis. The positionr,i7 +hpc;-xgfptg, e versus time graph of this object is

  An object is moving with constant non-zero acceleration in the +x axis. The pos py+e 989 gtt.z,dao7iz g8vwfition versus ti eg8+79,8of diz9vtgtzwpy. a me graph of this object is

  An object is moving with constant noq,y63b y xo o8cp8wo3 e:y.yumn-zero velocity in the +x axis. The velocity versus time graph of this object ,eyyop xwm:8uyy 6oq.o3c 83bis

  An object is moving with constant non-zero acceleration in the +x 3gno w7whl. uz f7;a 08z5id,ufvw/fgaxis. The velocity versus time graph of this object isf;7l7 vowdn, agz wu8gwf uf0.3iz 5/h

  The slope of a position ver ih *wk0gm9)x4 /gz.rpjgvk;esus time graph gives

  The slope of a velocity v f 7res/hwm w*,w3bxd,ersus time graph gives

  The area under a curve in ak4v.:bwfa;w+ bnmk. g n acceleration versus time graph gives

  The area under a curve6*p vop1mda0x oh3r.fb6 ms4s in a velocity versus time graph gives

  If the position versuo hshdn7 79lg*s time graph of an object is a horizontal line, the object i 9 ghnh*lo7s7ds

  If the position versus time graph o h)ym m1sdliy: vc)*8sf an object is a vertical line, the object isyhm i 8d1s)lysc*m)v:

  If the velocity versus time graph of an object is a horizontal line, the obt lsa79lcw8d(e ;k8 fob ;k7vsject is7dv8fe9bk 78t;k(as lw scl o;

  If the velocity versus time graph of an object is a s1h-7: 2vexgc oj+ldno*) mlmk z qr/o*traight line making an angle of 30 degrees with the gcooln7o +lx d h)rv-:/ *2mqm 1j*keztime axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find0(8 b3o-fsl gsxwg.vn both the distance travelebfxggs .ow-(3 nls v08d and the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How lonbi6gspwa 575e g will it take to move 12 km upstream in a river flowing 6.0 w6bgeai5 p75skm/h?

  55 mi/h is how many m/s? (1 mi = 1609 m)gi 5mj7d cja./

  What must be your average speed in order to travel 350 km in 5.1tzrn(s ; ;efo v5w;:xi5 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. Whaq9 6y.ft4ygb;skd7xz z,1h ekt is the average speed of the runner in m/s q6d749, ktz.1e; yyzgbkfsh x?

  A car travels 90 km/h. How long does it take for it to t(tu* td6l6jpmravel 400 km?

  A ly (light year) is the distance that liv od2v)s r o6xygcp)e e);x3)mght travels in one year. The speed of light is c )3)mvd6xr ;2vxo)se eg p)oy$3.00 \times 10^8 \; m/s$. 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 roa) ps3 6ca55cufx im-rvd and you look to the side for 4.0 s, how far do you travel during thisav 3x p6ucr-5f5i)scm inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 10*fvqv au lb4acz(/:v nzb;+z8 0 s, your average velfz *lz vca:bb v(u/z nv+;8a4qocity is

  A polar bear starts at the North Pole. It travels 1.0 km south+ka t,zez1 lw1y;apt2 , then 1.0 km east, then 1.0 km north a ze1p+ta 12;zwktl,y, then 1.0 km west to return to its starting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the North P+r8/l3f1 p.ckf l/p sjrem7jtole. 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. This8s f/rmk7ljp. tfpl +j3/1 rce 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 110 miles.fiy5d70 lwra8kq v b+:,ku4rj It then starts to snow and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. Howurywiqbjd0l8r4f: kkv,a5+ 7 far is your hometown from school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. What is the av u0m /wyioh ct+j :vl.n2pvf5u)1w:ab erage speed of the motor0 wy:1. jw2vump) 5 n:hiacb/fovlu+tist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.ynpbbd* 1a w7j4fhe)2s 8cyj 90 h at 100 km/h. What is her average s)bc9 s2 jd*7yfw1 ehjyanb48 ppeed for the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north foro .iak+3bj fxh4()nu /i ar;zr 750 miles. What is the average speed fouhz jaik f.34nbri)+;/r (axor the trip?

  In a 400-m relay race the anchorman (the person who runs the -abvk; +;qq:hglaz *ulast 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 runner can ba:k +l ; -qu;qzg*vhahave when the team A runner starts the final leg of the race, in order that the team A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 13 s. The car's aver85 sio5a49xliyf1j((sg erx v09shj mage velocity during deceleratio15sm xigo09vs9( jf(x lsyh4erj8 5a in was 70 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/*2 ;v vnmau(qh) pwhx4s to 160 m/s, at the average rate of huh2(vpvm;)nqxa 4*w $15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate of+ub)uk/pn3 i w $2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

  A cart starts from rest ani(qtbr95lp 9sjq v4m.ge0 )zgd 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 fo ;o-(d fwoh+5e,2zs)q xougr ur 10 s. It then speeds up with a constant acceleration of -(;oq h)wx5guesr u2o, d+ofz$2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 3.7 m/s jttev9et.b 0x(;(w h nexperiences a constant acceleration ow( . xvnh9bt;0(tje etf $4.4 \; m/s^2$. What is the cart's displacement during the first 9.9 s of its motion?

  A bullet moving horizontally to the rightmjsyro ;4pg5 ya k.*.v (+x direction) with a speed of 572 m/s strikes a sandbag and penetrates a distance of 80.43 cm. What is the average acceleratioykm a;rpsvo. 4yj 5*.gn, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft car2cmz2f e* etg2ap:j 4rrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. a 2tf:g jz2pm2*r4eecAssuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant acceleration x c0i s(t- b7lpso,w 5f4wacelo k(t8n;*avs;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 dooo zc-: ef h 2sr(5(kac/lir9istance of 200 m. What is its average acceleo :e5rf2 /okoc(-zilrhcs9( a ration?

  An object starts from rest and undergoen.ng z/0 sjpn7s uniform acceleration. During the first second it travels 6.5 m. How far will it travsn gz0n7./pj nel during the third second?

  An object is moving in a straight line with constant acceleration. Initially inxo5 p o.+ pa7-rg6bmrs3dw,yt is traveling atyra b,6poxs35 d7p.mr-n g wo+ 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 and accelerates uniformly atc2)jl-cn3jn4c nrz r * $3.0 \; m/s^2$. 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 j : 9 pql4:vmcysp-5e+fw*e uecan 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 traf+*b- )u8trm6isoj 3ndv0tkhpfic light turns green, a car that has been waiting at the intertvb* + thm)uor jd0k6i3- nsp8section starts ahead with a constant acceleration of $2.00 \; m/s^2$. At that moment a truck traveling with a constant velocity of 15.0 m/s overtakes and passes the car.
(a.) Calculate the time necessary for the car to reach the truck.    $s$ (only fill in numerical values)
(b.) Calculate the distance beyond the traffic light that the car will pass the truck.    $m$ (only fill in numerical values)
(c.) Determine the speed of the car when it passes the truck.    $m/s$ (only fill in numerical values)

  An object is thrown upward with a speed of 12 m/s on the surface of cm3* 5b6slgsuplanet X where the acceleration due to *l6 susg35m cbgravity 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 sur0 (er ,gd90jxo-ilfyakb .sp9 face of planet X where the acceleration due t,ej gfibak(p 9.y0 rdx-o0ls9 o 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 surface of planet X 1 8 rngughy2/swhere the acceleration due to gravun/2 gsgry 8h1ity is $2.5 \; m/s^2$. How long does it take for the object to return to where it is thrown?

  An object is thrown upward with a speed of 14 m/s on the surface of planetj(1alssou1q y/x)k +r1-pfj o5j bdn9 X where the acceleration duexkjq9assnp/(y)o5f 1bdl r-oj +ju11 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 thanr9qq :-uftrfh1fn7z( 9fz p2x 0.10 s. If your friend holds a ruler between your fingers and qf rf9 fnzxt-qrh :p7f129(zureleases it without warning, how far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.6 m/ehgs r;; 4 pgksm-r;c(s. What is its velocity after 3 4p grm gc;h-s(e;;ksr.00 s?

  A bullet shot straight up returns to its starting point in 8 s.0x ;ge1cr/dw1dbb g-b What is the initial dcrbwd/e1b0b x;g1g -speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long doer 2y18j zra q4q.gkrm;s it take to return to itsa zqrgyqrk ;1m4r.8j2 starting point?

  A ball is thrown downward from the top of a building with an initial speed oj.jw,*cc,n0 g)t l.l v gi:kqpy;u) vof 15 m/s. It strikes the ground after 6.1 s. How high i*wj .pu)t0;ly vjc,cglo:k,n.g )qvis the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fill in7jiu3a 7d i/lk numerical vali3uil jd7ak/7ue 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 spq-c, qe 4o2it8hb 0ukneed of 22.8 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 6 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 6.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is thera * ):bobtc pu-:qo 7y2pn,ca velocity at t = 1.0 s?

  In Fig. below, what is the velocity at t c:h1q4,/uipx fkf yl9jd2 z/ f= 2.5 s?

  In Fig. below, what is the velocity at t = 4.r e-)kogqs0 iwk8/pw10 s?

  In Fig. below, what is the velocity at t = 5.5 pd581axx9utp1,rredb/u 3kas?

  In Fig. below, what is the average velocity +p ,.fliy;az*z . f(vaga +qj(ynohj8from 0 to 4.0 s?

  In Fig. below, what is the averag3ad55wu gld cv 3td+- lje*-toe velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleratli4mf l,l9ou(/e xz,-, yqivcion at 1.0 s?

  In Fig. below, what is the accelerat so(f(zz3s *xcion at 3.0 s?

  In Fig. below, what i igvy8qkcn5) 4s the average acceleration from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.0 w-q oi )2sedo*(y8ayr20vzk+h2t1-cgrchf xs?

  In Fig. below, what is tue0/ f5m)uw i8sc i84yvh3biphe displacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|vehqp4 vje gh.ia.73o8ulocity}

  An object can have a varying speed if its velocity is consg gcw0;14vf fptant.

  The velocity of an object can be ne2 h98t kh,n w:l 5msit;aun2ohgative when its acceleration is positive.

  If one object has a greater speed than a second objr*mxnsoinn /v8)e bjh0aq),0 ect, the first must have a gre n*x0inbs,/r 8) ajonhm0 e)vqater acceleration.

  Two cars emerge side by side from a tunq5ya9l; jte(y8d1ukn u- aj:nnel. 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 accelv4 rudu ;) totorh*b/ l;-2kgseration decreases.

  A baseball player hits a foul ball straight up intoweal ;usnl60 / the air. It leaves the bat wil/ a6 nsule0w;th a 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 object speeds up, what is happeg5( wrsf+1ldwv7yate. wax 2n;htm9j5ec4+d ning to its acceleration, how does it change if air frifdx91w e ce 4ntv h;warm7t2l5y wa s.d(+jg+5ction is ignored?

  As a freely falling object speeds udcz8 a).-y aa1.anxcl fi8m. sp, what is happening to its acceleration, how does it change if air friction CAN NOT bmasn)aldx. 1. -if88 ayac.c ze ignored?

  An object that is thrown vertically upward will d+qg )p hfg.eg :x:o k*n;ayp 99/zsrjreturn to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, :zf qy g.9nax9 h+k/j*:odg;egp p)rshow will this result be altered?

  An object can have zero velocity and nonzero acc1ud zs2jr )h :li0; k+lrr;wwqeleration at the same time.

  An object can have nonzero velocits)pz2pa ,l0p)2j 3f qfz)my 2q2pluq zy and zero acceleration at the same time.

  An elevator moving froes7qli r jm4uuo*,1j hb/y//um the second floor to the fifth floor making no stops along the way has zeu,/b yql //imr7 hj *1usuoej4ro acceleration all the time.

  A rolling ball moves fromb 0f0ph.fl cp*) *goeasw3j9w $x_1=2.4 \mathrm{~cm}$ to $x_2=-6.3 \mathrm{~cm}$ during the time from $t_1=1.1 \mathrm{~s}$ 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 $t_1=-4.7 \mathrm{~s}$ is at $x_1=2.8 \mathrm{~cm}$ and at $t_2=4.1 \mathrm{~s}$ is at $x_2=7.8 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-mile wbk 1xf9xr*r 88fmy1y1 luig(($1 \; mile = 1609 \; m$) track in a total time of 9.9 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, moving 115/bmr51q g+ll6ny77bow ut. *z:fckvd m away in 8.1 s. It then turns abruptly and gallops halfway back in 4.5 s. Calculate (a) its al7/no mkwb cuvz +5r7ftldyqg 6*.1:bverage 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 d* bn:p 7lrkg ;xamq**h-8wgi:wwb 8j$13 \; m/s$ to $23 \; m/s$ in 5.4 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 from yztr jt57 3dxu 44jps;$16 \; m/s$ to rest in a distance of 70 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a s qwl*bj)3itp, ( r1wjkpeed of $26 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.4 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of u *e l)dssngb7tiv 32h:rfp4/the blocks to essentially top speed about vth 7pe2d/r) g4fsb:3l inu*s$11.1 \; m/s$ in the first 12.6 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 fp/ s3fnec; (ferom a speed of $19 \; m/s$ to rest in 4.44 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m long on the highway. Assumin4 2tz wnh0g5l*y,rsu gg a dec uyhtl20s*w5,nr g4zgeleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trck-r+-33b +f jd aujfquck 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 run in less than 5tsc);shx)bkd *9tzf) iwg,f30.0 min. After exactly 27,*;c9s)kt5fxst di) )b fz whg.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?    $s$