Suppose that an object travelsz hd*f 0j)lbpqqu,. *a3 s9qcu from one point in space to another. Make a comparison between the displacement and the distance tral, a .qq*z)9sp cjfhuq bd0*3uveled.

  When is the average velocity of an object equal to the instantaneou9*x k2qhy38adksk :l xs velocity?

  A new car manufacturer adverti; kppir/aa mo.qg52 d;ses that their car can go "from zero to sixty in 8 s.k5 a/g2pdqmo;pr;ai ". This is a description of

  An object moving in the r lk3jx( d .h4gs9rky;+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 so+g/ 6, kwpteblow down as it approaches a traffic light. Make a statement concerning its ac t/p6 +og,kbweceleration.

  Suppose that a car traveling to the West (-x direction) begins to slow 8dp3qu qbko k; j718zwdown as it approaches a traffic light. M uk jdq7k;z8q38 obpw1ake a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statemg0 9psuzft(g/ent concerning its accel(ftz9s gu0p/g eration.

  If the velocity of an object is zero, does it mean that the acceleration is zero 8o4vueuu0vvi / lpm.4a3ad1-1 ohwcx? 08coweu/xpv dm4a-ol a 3iu. 1v41uvh Support your answer with an example.

  Can an object's velocity change direction when itmt4w/ oifo l3 se- m36+ qu1mhc:trny/s acceleration is constant? Support your answer wis 6c eioh3orn-w/1f/: mm+tqy34 tlmuth an example.

  Suppose that an object is moving with constant acceleratdgogmdbs2)og cf8;:su 2.th/c ll7a6 ion. Make a statement concerning its motion with resp. 7:hum )doc62sos/8c agggtb2l;dflect to time.

  Can an object have increasing speed while its acceleration is decreasim77(s. onld fing? Support your answer with an exa(7nflis 7mdo .mple.

  Suppose a can, after an initial kick, moves up along a smooth hill eb7to:x *nm v,of ice. Make a statement concerning its acceleratim,*7x:tebon von.

  Under what condition is average velocity equ4 .g44+aarzi) og 1v/ :gv;laviujnseal to the average of the object's initial and z:1g)ave4 .;oa 4ai lg4n/vgsvi+urj final velocity?

  Objects A and B both start at rest. w :ahb pfz6s;)nl(t*xThey 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 compaapn(* )6 ;fh:bts wlzxred to that of object B?

  Objects A and B both start from rest. They both accelerate at the same rate. 99djrl +9uvf7r/qrk:zh xii f5e(t bw9wok.: However, object A accelerates for twice the time as object B. What is the distance traveled by object A kwir:d:7.t 9uwjrf5beofl9 hrzv q +k /9x9(icompared to that of object B?

  When an object is released from rest and falls in thbjf pol44crm)wy d:0r2 5ymo t142 baue absence of friction, which of the af4y42: boojb 25tm4 0lrrm y)dw1uc pfollowing is true concerning its motion?

  When an object is released fromlte4x4 i+5r53rwbid g m7vbx 2 rest and falls in the absence of friction, which of the following is true co4rig5dl5 ev7+xb2wr tbm4i3x ncerning its motion?

  Suppose a ball is thrown straight up. Make a statement abo ke.(k)cewqwk-klj4 6ut the velocity and the acceleration when the balwkwekl k-ecq( 4j 6.)kl reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before it ruu;o+aa-/i k peu/i;apauo -+k aches its highest point?

  Suppose a ball is thrown straight nm f4o9og)q9d-6dkhx up, reaches a maximum height, then falls to its initial height. mok9-hfx o qdg4d96n)Make 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 or4v1v l xoljw+efs4*l 8:1*xq z3 tiuheight, then falls to its initial height. Make a statement about the direction of the+vl4xs4ljit1el*vfur1xz q:* o8ow 3 velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward mwedjdr. -g e0f(bwt6 )*b0 hqin the absence of air resistance. Make a statement concerning its acceldb6ghwfd).wt*bj e m 00rqe(-eration.

  Suppose a skydiver jumps from a h(-t *bdpk8u ecigh-flying plane. What is her acceleration when she she rekut -pe(b c8*daches terminal velocity?

  A ball is thrown vertically upward with a speed v. An identfw +v,; g1+dvoe+r3s/rq l ojhical 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 thatl +,eg3d q+v/1;shwvrorof j+ of the first ball? (How many times higher does the second ball go than the first ball?)

  Ball A is dropped from th7n81m6l 3d o8egxwmem e top of a building. One second later, ball B is dropped from the same building. As 631womem 7en88 gdmlxtime progresses, the distance between them

  Ball A is dropped from the t nl4oj j,;(xdo6rez w9 :hmr,nop of a building. One second later, ball B is dropped from the sa,ro e zjrj,m4do;h6w :xl n9(nme building. As time progresses, the difference in their speeds

  Two objects are throj 6 vj8v-2*s vr epjefddq.)i/wn from the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. Whr- )/8sejejv* p6j f.i qdvv2dat are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown u:qymeq 6+33g2 f;fz,)ub:fn0blglsuz0buw straight down from the same building. They are released at the same time. Neglect air resistance. Com;uu3zq6qbl+:,)bl uug0bysf gen2ffz m w30:pare the accelerations of the two bricks.

  An object is moving with constant non-zero velocity iqlc,ngh 8)8tzz vi63-ld+ m xln the +x axis. The position versus hz,vt3l6d8)+lzqi-lm8cn x gtime graph of this object is

  An object is moving with constant non-zer tezvz x* :9512zn7gme xz8ogno acceleration in the +x axis. The posin gtgez5:vx7m19e8zz* n2 oxztion versus time graph of this object is

  An object is moving with constant non-zero velocity in the37j6odw txw))yz1p.qt rkc x. +x axis. The velocity versus time graph of thd p)67zox. rkwjty twc.x3)q1is object is

  An object is moving with constant non-zero acceleration in the -.avk9 o5s 6jw+vyayb ,kbcc 2d+ /hls+x axis. The velocity versus time graph of this oa 6cs+ jdyhkk2+y5-a./w 9,bv vlo bscbject is

  The slope of a position versus time n hxnk(+e)1q qgraph gives

  The slope of a velocity versus time x1 l av6-a;hxigraph gives

  The area under a curve in an0gzpv+/u kncc 2li l ..q4(6a6o aljdc acceleration versus time graph gives

  The area under a curve in a velocity versus kc7 jnp- 7p497wiitrptime graph gives

  If the position versus time graph of ab;kwi:a3zz3r )we o,bwjdo,jtn w5e6nb1f )(n object is a horizontal line, the object bawbdij51 z6f)3( r,, n wo z)3ejo tb;:wewknis

  If the position versus time graph of an object is a vx1 d e/ wiaq:sqn1- qc5fc6y/nertical line, the object is1e6ccn-dnqqs qx/if5:ya1w/

  If the velocity versus time graph of an object is a hori-2 kjv7wj9j3rtllvxoi /6m3yzontal line, the object i3lvk-/ yt9 l3jwv72jrjx mi 6os

  If the velocity versus time b9z4y yokt ,y:graph of an object is a straight line making an angle of 30 deyt :y yk,49zbogrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. F;wli8ex )y/y gind both the distance traveled and theiye ;wy)g8 /lx magnitude of the displacement vector.

  A boat can move at 30 km/h in pe t :7iqmaz+ 1um83pbstill water. How long will it take to move 12 km upmu87mp i+p 1a3bz:etqstream in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609 m++raicy5s ;lcgk 8fs-)

  What must be your average speed in order wg9ban6m.e3b to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 minxthcf l9z// 5dqi5 /be. What is the average speed of thc/5h/ bq/ldi9t ef x5ze runner in m/s?

  A car travels 90 km/h. How long does it take for it to travel 400 ;gh :8rgv4.4jzx 3uxa diu m5c53wsju h+lq6s km?

  A ly (light year) is the distance that light travels in one yea0z/ t--o0aq yf /smcnd(qbh2 lr. The speed of light isl2 (0bcanh0m q/syot-/qf-zd $3.00 \times 10^8 \; m/s$. 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 the side for 4.zhj3urkq :)0t r*3q gpxm:5 k,afq(cm 0 s, how far do you trxjrgh3 ,m mzc )p:q3 rt5ua:k *(0kfqqavel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, your .)z2 9 vw4wcazj/)wzfvd/ fzeaverage veloc2zw e)zvw4 fvjfwzda/z /.)9city is

  A polar bear starts at the North Polv sx9t61p xo9y.bv 50ks 8zchpe. 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. pyv ckh ss8 0.vx15bo6p99tzxThis trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km+3y69i v tyane south, then 1.0 km east, then 1.0 km north, then 1.0 km west ty 3i+y9e6 tvnao return 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 az tqj0;n i.nvnz1x.:pt 55 mi/h for 110 miles. It then starts to snow:xp;0n 1 jzqn.vnzi.t and you slow to 35 mi/h. You arrive home after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km:yii uni6 )5iqw3 9tjcv: ktr9 at 80 km/h and 160 km at 100 km/h. What is the average speed of tc5iik t9rj:tu)q w 3nv iy69:ihe motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 13 y-3+;kf eb)9fbg8c p/5r pmocmro eo00 km/h. What is her average speed for the tppcoeor53+eg- 3) yb 9of/mmrkf 8;bcrip?

  An airplane travels at 300 mi/h southht3hv :6p+e vm)a1feu *ehhk9 for 2.00 h and then at 250 mi/h north for 750 mmkhv +p 3ev):h1e e*f 9hu6htailes. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the az0bhzid1/ e: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 runner czi:ab01dz / hean 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 comem7klqx.l4).s t,h d fes to a stop after 10 s. The car's average velocity ddk hxf)l4t le.sm q,.7uring deceleration was 75 km/h. What was the car's deceleration while slowing down?

  An airplane increases its v sd kfjwfq 28e4tu4,6cbh0q/ speed from 100 m/s to 160 m/s, at the average rate of 8s0/eudvqcbfqw26th 4 k ,jf4$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 k6 -hyz k-x+3)uh nwucim/h accelerates 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 andhee+ h (.1yxrv 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 10 s. It then speeds u, wt v(fpeze (a:z)2uxp with a constant accelerationzep2aw:)z(x v, (tfue 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 3.3iuvg:g0v55m6jev7j4 :cy vzo m/s experiences a constant acceleration of vge5o0vjij m zv7c 4:5y:6uvg$4.1 \; m/s^2$. What is the cart's displacement during the first 9.5 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speedhy9fq w(b qew sgs,6+- of 451 m/s strikes a sandbag and penetrates a diqswq6 b 9s(f ,w+-heygstance of 85.24 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launc+/ a5z ay6c- t0aevrcnhed 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 a t/56e+c vczr-naa0 yacceleration is constant, what is the length of the catapult?

  A car starting from rest moves with c+s+r em5d- 4kb a(vect24ikrmonstant 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 8yg x8 lgn)x+uqjt7;m:8qlpde i*-eb2 0 m/s in a distance of 200 m. What is its average accelera;g+xel m*qt8 u 2npxbgiq j)ld:8 7ey-tion?

  An object starts from rest and undergoes uniform acceleration. During tie *ir0p4r,gzhe first second it travels 4.7 m. How fa0zgiei4rr* ,pr will it travel during the third second?

  An object is moving in a straight line with constant acceleration. c8rhctw : p8(lInitially it is traveling at 16 m/s. Three seconds later it is traveling at hw8c(l8 pc:rt10 m/s. How far does it move during this time?

  A car starts from rest and accelera)+0z14kmlsf 8frffvu tes 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 decelerate a g 4x gqjjff01j j.,tpx.4s4rgt 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 atb-vm8at+*4jo pcc2ry the intersection starts ahead with a c*- t+p2 mcj 4yabc8ovronstant 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 planet X whe5 gzt ;dybe44qre the acd 5;44gzbeqytceleration due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upward with am) nhug)x v:5u speed of 12 m/s on the surface of planet X where the acceleration due t5nx:)vmu )ugho 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 - lchx- mx l4e5(ztdg8a speed of 15 m/s on the surface of planet X wherm (- lxltz 4c8xg-h5dee the 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 surface of ul) v byah9o.in i+:z,e l.4uzplanet X where tylhba .zv4ze.: +ui ),uonli9he acceleration 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 frie5d6tq2en x -nlde3xx 9nd holds a ruler between your fingers and releases dxt2xx6 n-9qdle35 neit 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/s. What is its velocity after vs f7sldv+q6eur.aook9 f8053..oq0f9rol+ sfdkvvs8ae7 u5600 s?

  A bullet shot straight ub6 am v(, b8bqfu(4ucjfj8 np-p returns to its starting point in 12 s. What is the initial speed of the bulu,m b -j8vu46facpjb(nf8bq(let?

  A ball is thrown straight up with a speed of g(c *j-(ujapb 36.0 m/s. How long does it take to return gbjpu(- (jca*to its starting point?

  A ball is thrown downward from the top of a np1tq k-, htr+building with an initial speed of 21 m/s. It strikes the ground after 5.2 s.+t,nq-k1rp ht How high is the building?

  A ball is thrown straight up with vg7hd d;0yk+ /;nvgcja speed of 30 m/s. (only fill in numerical value in the blav jgd0;dvygnc/;k +h7nks)
(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);zr /kjw)b il with a speed of 49.5 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 14 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 14.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity,uzr y*jqmps3 ecm* d7 yrq6), at t = 1.0 s?

  In Fig. below, what is tcv ah 31x otk8y22waj0he velocity at t = 2.5 s?

  In Fig. below, what is the velocit,v.gwex f a frz3p /ezwj0rn 6v3xf9+1y at t = 4.0 s?

  In Fig. below, what is the velocity at biimj t75n.hta zhp :.1//wxu t = 5.5 s?

  In Fig. below, what is the average velocit opy4rk 7e49siy from 0 to 4.0 s?

  In Fig. below, what is th) *0inaq52 skxoe(vrde average velocity from 0 to 6.0 s?

  In Fig. below, what is teqdo ,n 2qpy(3he acceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 s?vik .xfi,-v ;a

  In Fig. below, what is the average accelewsz+0pdoa9 h:k*ug y 8j(:2zorps6jf ration from 0 to 5.0 s?

  In Fig. below, what is the average accelere.slx2sc9 j4s9c es 0cation from 0 to 8.0 s?

  In Fig. below, what is r5 vk+f +a 1h,-hdy;sxcax5 vythe displacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speedamwk; khl: x02(z p y vhz54ws(trb(a(|velocity}

  An object can have a varying speed if its5twg c). end9s velocity is constant.

  The velocity of an object can be negatig6jeqrwc3lo 1c(t ;; sj;0ewive when its acceleration is positive.

  If one object has a gr 19 iverzcc g*ehv8)j(eater speed than a second object, the first must have a greaterchj evrg8vcize)(9* 1 acceleration.

  Two cars emerge side by side from a tunnel. Car A is ) hfkwd4 sw,5ftraveling 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 increoo90,tkzc;5exevs. xzsw9 73 l)s 1soxn ;c bgasing in speed as its acceleration decreases.

  A baseball player hits a foul bhl.c6x 6th em .9lw2quuwc,3 fall straight up into the air. It leaves the bat with a fx236wchm ecl ,9u. th6uwq.l 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 speea;.9. 9a c0juwww* 2vpqclfhzct/k/ pds up, what is happening to its acceleration, how does it change if air frict;pwqc 29* vflp.0 uw.k/c azaw htj/9cion is ignored?

  As a freely falling objecchw mrb1m0a p;m4p(wtnut.* u8nw+ yny h566xt speeds up, what is happening to its acceleration, how does it change if air friction CAN NOT be ignoreum 0y84w ma 6+*ypw;rhm(. bt5h ncwpn61tuxnd?

  An object that is thrs8nz:bz 9n3x yown vertically upward will return to its original position with the same speed as it had initially b 83nsxzz9:yn if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration at the )i;r 6rxkv.q li/c ii,same time.

  An object can have nonzero velfnev,/ g9iurtz :5w* tocity and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floor making no stops alon-h 1odjh u,7njg the way has zero acceleration all th7, djhh-1joun e time.

  A rolling ball moves frotq6ap a +lhn1u;,nd3lm $x_1=2.1 \mathrm{~cm}$ to $x_2=-5.9 \mathrm{~cm}$ during the time from $t_1=1.5 \mathrm{~s}$ to $t_2=6.1 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-3.5 \mathrm{~s}$ is at $x_1=3.3 \mathrm{~cm}$ and at $t_2=3.4 \mathrm{~s}$ is at $x_2=7.9 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complexxhh 0 /fs*rp5te laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.8 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, moving 107 m away n-ws41gs+w) +poxz k-+ui1b8g slf mlin 10.7 s. bs4g -xk1w 1sfl wns++i+mlzo)8 -pguIt then turns abruptly and gallops halfway back in 4.6 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 fromzof1/ sc; 3cds $11 \; m/s$ to $22 \; m/s$ 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 fromqd d86v( yj nsr6fpauw/.zw. ( $21 \; m/s$ to rest in a distance of 78 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reaccw4 mrjeid, ;,0trls jh xobn+uc/-.3h a speed of $25 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $3.0 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the i5 izr)vapeatt2rv n;i1:(06hh x* lu blocks to essentially top speed about it0*vp2r51hei );r(tvuhxz in l6aa:$11.0 \; m/s$ in the first 13.2 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 uniforme5-df -j i;; gr kx-r,abk*ub8ke6rhcly from a speed of $17 \; m/s$ to rest in 5.94 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. Asss;g np1r41vn auming a decele1v ;ns 1ag4pnrration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck gwtfdb0cov1 0 3oing $25 \; m/s$ 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 thanzj n:j*k-( ggy 30.0 min. After exactly 27.0 min, there are still(*:gynjj k z-g 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?    $s$