Suppose that an object travels from one point in space to another. Make (fy60 hl uh9rka comparison betfku0 hl(69yr hween the displacement and the distance traveled.

  When is the average velkv82 mtdq( fp:ocity of an object equal to the instantaneous velocity?

  A new car manufacturer advertises: mge 97k1 y /:9t jg9nir)lsiylkn:ka that their car can go "from zero to sixty in 8gjli9 9kanm )te:ln71k9rk/ ys: g yi: s". This is a description of

  An object moving in the +x axisbnno gr,,5w o0o: v)n2svt q lf35b-dl experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x di ;y.u r5g0eyp1(5ap+ wfimicwrection) begins to slow down as it approaches (;ie .1yca50pfw +ui rymw g5pa traffic light. Make a statement concerning its acceleration.

  Suppose that a car travelz/lb7ga ;y,qypt+ 6*cpz;mczqm(a+x ing to the West (-x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its accelerationb6+p xya;;(7plq gm+zzayqmc/* czt,.

  Suppose that an object is moving with a con1(5ie4ol lc) z snjf.fstant velocity. Make a statement concerning its accelnes .z1ci f)4lf(l 5joeration.

  If the velocity of an object is zero, do fc4d 0h6gh vfw*5y2sq2yf k3ves it mean that the acceleration is zero? Support your answer with an examph2 6 yvgkffy4 wd*0f5cv3s2hqle.

  Can an object's velocity change dig17 .6,dgkryc4ez nw trection when its acceleration is constant? Support your answer y6ngk7ez gd4.1,rwct with an example.

  Suppose that an object is moving with constant acce;ga)t+0g0a fkc4em cjleration. Make a statement concerning its motion wgfac+t0a0) kgm c ;j4eith respect to time.

  Can an object have increasing speed while l.lq 7/w *m3k:4aki 9pchjvjwits acceleration is decreasing? Support yojlw i9*wp4/qjv7.3k chmka :l ur answer with an example.

  Suppose a can, after an initial kick, moves up along a smooth hill of ice. v1 vgzx msd+*3 Make a statement concerning its acceleratio3vg*+m1sd xvzn.

  Under what condition mdgt px:yx;6: y1m-: mqjyi9his average velocity equal to the average of the object's initial m;mp h :ig yyt:jx:xd19 myq6-and final velocity?

  Objects A and B both start at rest. They both accelerate at the same rate. au/boq5 fx3vz72j) w pHowever, object A accelerates for twice t3v/z7 )xwf2o 5japqubhe 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. uts3tm*ep2g/vuh6 6b sq snue8,8n ,:f-zxfd They both accelerate at the same rate. However, object A accelerates for twice the time as objes/6u :f3ng-eht s6ps8ubm e zv,ux,8 qtdf2* nct B. What is the distance traveled by object A compared to that of object B?

  When an object is released from rest and falls in the abzgdnuid 63 m(-sence of friction, which of the following is true conce ugdin-6d3z (mrning its motion?

  When an object is released from rest xo 4r.(koe, sent h+ 1uvam-8mand falls in the absence of friction, whichn8t r ks u+-vm4 (x,m1o.oeeha of the following is true concerning its motion?

  Suppose a ball is thrown straight up. Make a statementia8w/p; j3 d c caqhg27goxy12 about the velocity and twa/ cj83 d7qax 1gy2c;hi po2ghe acceleration when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What l-vul)w p2u/n is its acceleration just before it reaches uvpn /2lwul)-its highest point?

  Suppose a ball is throwng inmja nvh/7v,6q(p92cgf(j straight up, reaches a maximum height, then falls to its initial hg gj2f cj/hn,(aiv69n(mvp7 q eight. 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 8grzh g /*rtud+45tpw height, then falls to its initial height. Make a statement aboutzrp4h+g8u5 t*/g d wtr the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward iz) 3it:1z/9wldsx.8wcqxgy a n the absence of air resistance. Make a statement concerning w/ z91x qg.3ixy 8td: szac)wlits acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her acceleration wheb - v )-qrzaov1z2b09zjv,stun za-9tv0zj )-ubr qsvo,v 21 zbshe she reaches terminal velocity?

  A ball is thrown vertically upward withu( i3(elgmda+( pzf+y a speed v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of fu+m( ( a+ zg3(ydpielthe maximum 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 o(+ak m9 o x88y7qfc)wbmuy6dqf a building. One second later, ball B is dropped from the same building. As time progresses, the distance betwmyby(9m wa87kd c 8)6uqqxf+ oeen them

  Ball A is dropped from the top of a building. One second later, bah7n4xxs) d9 yzz 0qe0.k7o pkmll B is dropped from thp.7) kds 7nxzomz 4qe yk009hxe same building. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, fu)rt*(msw;dhnn ed5* 29phyand the other is thrown down, both with the same init ws29dn y)pf;u *thh*e5mrnd( ial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is ezgxia)qyn)fv 7 ; :z+thrown straight down from the same building. Thz+g; : ny qfxev)ia7)zey are released at 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. The posib;qy-qo5,nloq 18 ldf yfp yi:(8f0it tion versus time graph of thfyo:fqi tyo0881qi-,;5l f bny lqpd(is object is

  An object is moving with constant non-.,bq7;dq f7es3hh c mh4;ltcuzero acceleration in the +x axis. The position tmuhq fdl3;ch ;s 7.qhcbe47, versus time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. Th(o k f4m(kkrn0e velocity versus time graph of this obje0(r (no4kfkmk ct is

  An object is moving with cons/a6tl+k ra)k*bjtv,q tant non-zero acceleration in the +x axis. The velo v*6blaqk/jtar kt+ ,)city versus time graph of this object is

  The slope of a position versus time graph givesp5v7u+dx5ck.q r1f aoiil c ,hu3e;*p

  The slope of a velocit/et ya+wtjo+ ,yam,4l4.k zjsy versus time graph gives

  The area under a curve in ac xq7nak:-w f/n acceleration versus time graph gives

  The area under a curve in a velocity /s3d*e( 7 guf9 a;:+of;wdx y dimilieversus time graph gives

  If the position versus time graph of a- yjtlxs/,7mf-h;kr l ebe /;fn object is a horizontal line, the object isx eybjerh ;; l-/s/fflm7-,k t

  If the position versus time graph of an object is a vertical linetti*1 .sh 0th/dz8cdz, the object is 1 h8dtz zid*/hs.c0tt

  If the velocity versus time graph of an object is, ki9*xau4fp h a horizontal line, the object isauf i9*hx,4kp

  If the velocity versus time graph of an object i ovy+h 6z4fo :r:n: 2-fbtloacs a straight line making an angle of 30 degrees with the time axo:aloc:6try:h+o- z b4 vfn2f is, the object is

  An object moves 15.0 m north and then 11.0 m south. lvyvv)/a3i2 s Find both the distance traveled and the magnitude of the d a)viy2vs lv3/isplacement vector.

  A boat can move at 30 km/h in still water. How long will m92n kkqf*xh)it take to move 12 km upstream in a river flowing 6x)m k9n* hfk2q.0 km/h?

  55 mi/h is how many m/s? (1 mi *amw /kzbx-l41 ctb9n= 1609 m)

  What must be your average speed in order to c na;p04c0 mzbtravel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) inn-deony*-z z+p xi,s5h4t c.g 2 hours and 57 min. What is the average speed of the p+ zz-sdho*g x ,neci.n45- ytrunner in m/s?

  A car travels 90 km/h. How long does it take for it to travel 400 km?4z/ey p8h6igp

  A ly (light year) is the distance that k/2ohz+hy 0ryg- y/so+ha 5fclight travels in one year. The speed of light isf+o k- yh2a5g+szcy/hryoh0 / $3.00 \times 10^8 \; m/s$. 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 r,f64-kpqkkr1 rmbu+ ioad and you look to the side for 4.0 s, how far do you travel during this inattentive periodr+pkuik 1,k6- mr4qf b?

  If you run a complete loop arou2h+- vev 7sernnd an outdoor track (400 m), in 100 s, your average veloci7+ner2 se-vvh ty is

  A polar bear starts at tk 83k3sl-yy annavk)k2 g* uw/he 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. y*2uk) kn wk-va/y g3a38nksl What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 c)za7klk06p ikm 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 veloc)0la c 7i6pkzkity?

  You are driving home on a o0rnh.u+ 4 dpmweekend from school at 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 from sdn. h0ou4+rmp chool?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. Wbue0w 3wjdw*:5 g.yrf hat is the average speed of the motorisgw e:5f3d*yrwbwj.u 0 t for this trip?

  A motorist travels for2i6 ijt+ bikv+ 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her average speed t +ikj6 ib+i2vfor the trip?

  An airplane travels at 300 mi/h soutx e8u9( 5jx/a )suzfmah for 2.00 h and then at 250 mi/h north for 750 miles. What is the average speedj/(9)sauxzu f5 8emax for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) ghi9-aotx:uju;0m zr;( yew8 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 have when the team A runner starts the final leg of the race, in order that the te-wu8to ;:0heaz(mxy;9 urjg iam A runner not lose the race?

  A car decelerates uniformlwpsbo aw7i .)2y and comes to a stop after 10 s. The car's average velocity during deceleration was 48 km/h. What was the c.biww7a2p s )oar's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 160 m/s, at the average ratnb; evg6 1+nrae of na;+en6vg rb 1$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at bu-a( atxl):n5 :zzk5e(yfdvbl61 muthe 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 rtt 8-mt2p gsxvly52*uest and 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 up with a constant accelbd.)jdh, 7tn j1;vnc, .egrrferation dd7c.net1 jvgb , r.fr, ;)hnjof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial vd1ldzx5 7t: voelocity of 7.8 m/s experiences a constant acceleration of :5dxz1vo dl7t $2.1 \; m/s^2$. What is the cart's displacement during the first 5.9 s of its motion?

  A bullet moving horizontal f).q*ivtgk8fcu 0iv 7ly to the right (+x direction) with a speed of 464 m/s strikes a sang)f .8qf7 uc0iv*vit kdbag and penetrates a distance of 32.79 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched fromdau+rl9vja9i e1c0 ocx; l9q : 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 acceleration is constant, what is the length of the catapa c0 l;1xdiuea :9o9qv clr+j9ult?

  A car starting from r8y,2 se vka9eoest moves 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 average)+9;rv lh ktiv acceleratio9 +l)rvkt;h vin?

  An object starts from rest and undergoes uniform acyeco8bnocwu /i,5-j4 celeration. During the first secoo,5c-4 y/jw ioueb8ncnd it travels 3.3 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Incgf5w 7n jx/9hitially it is traveling at j/59wn g7hfc x16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from res0( hvk ) yca*c)lmklj:t and 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 can dece(y+)apsgqu+ wb u 7)*j .cxqctww50 qclerate 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 green, a car that has been wy+ af uec8:-kvc)qu0lt)if7 yaiting at the intersection starts ahead with a constcfvyq): )8cuyla+f7k ut e 0-iant 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 upwarg8ugd:u 4g gm: eu;9nxwh,am9d with a speed of 12 m/s on the surface of planet X where the accelerati duwg49uag h:98,;e mnxu:mggon 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 of 12 m/s on the surface of p z648 bz:tifralanet X where the acceleration due to gia64 t8fz: zrbravity 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 m0s4 gu,6xv2 e,thys uuw1 k3ns/s on the surface of planet X whe, suusy,32 wve6t04 1ghk unsxre 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 planet pkgc-w gna9.(x/ -pmwX where the acceleration due to g /9p(p mg .-wkcw-xganravity 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;j;nx/rx)r sw friend holds a ruler );wx;x/jsr nrbetween your fingers and releases 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/s. ektak*g w1 6m+What is its velocity after 3.006m*g+k k etaw1 s?

  A bullet shot straight up returns to its starting point in 19 s. What is tj:zqx 2 s3 6zjp; snru9hbis;/he initiarsbj6p/3unq9s:x ; s2zih zj ;l speed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How long do -wl (npqd2xr;es it take to return to its starting pointpl(2-qxdr wn ;?

  A ball is thrown downward from the top o6cskpynxwq0 mv; v8v:fc /57hf a building with an initial speed of 15 m/s. It strikes t 7k vw6c5n0xs;hy8cpfq: v/mv he ground after 6.6 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. +m)al qknyh 73htfnb5h85 :sd(only fill in numerical value ifqsy)nd3an 5 blth8k5m 7hh+:n 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 strasg0(u fw8ej98 : .9y8fy9 kwpjrh:dc e(kbcdgight up into the air with a speed of 26.9 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 15 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 15.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the ve u+ gabrid7tfm09 w/v1locity at t = 1.0 s?

  In Fig. below, what is thk-z a.z9 vtvx9dru u.pr 6.(ghe velocity at t = 2.5 s?

  In Fig. below, what is the v4aglg ;h,8fc telocity at t = 4.0 s?

  In Fig. below, what is the velocity at t = 5.5 ruug07pv,sz4 s?

  In Fig. below, what is the average velocity from 0 to 4.0 tos+ l(u nm,l bwe-5r)s?

  In Fig. below, what is the average vej2h7dqs)a - ao wj w(,m(ovh8nlocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration g x )4 xxsw.x 4gvyqf4v5wo:6aat 1.0 s?

  In Fig. below, what is the acceleration a0 p s ojywb/e+;on(5nct 3.0 s?

  In Fig. below, what is the acr on ryo/30hb7)xqk 0verage acceleration from 0 to 5.0 s?

  In Fig. below, what is the averageyo( wltvto sjt(52q(, acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 to 8.0 szd+9de h/ )l*+f:/wed hujfxtbrf)ib;/yx k.?

Does a car speedometer me .mfp nc0 q.uvem3u5n+asure speed, velocity? {speed|velocity}

  An object can have a varying speed ifz9z- gl;lja: *8y e q.krn7lia its velocity is constant.

  The velocity of an object can b +4bqqfb9kzu3;/jc sge negative when its acceleration is positive.

  If one object has a greater speed than a second object, the first must have a gls 0ini+a+am7q u1.vxrea.qau01m7 i++a xnisvl ter acceleration.

  Two cars emerge side by side from a tunnel. Car A is traveling wiuwfu4 uq a606bth 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 increa* zd/8 /xppqiqsing in speed as its acceleration decreases.

  A baseball player hits a foul 6a fdo 6br 2xf.aw6;twball straight up into the air. It leaves the bat withfdrb6fo t6x. w62aa;w 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 oqh7tek zp5 f55.)+axtlg/stlbject speeds up, what is happening to its acceleration, how does it change if air friction is ignorz5/t7+hx5la ) gqtlfe 5t. kpsed?

  As a freely falling object speeur/-h5nj6prmv1jy7 nds up, what is happening to its acceleration, how does it change if air friction CAN NOT be i /mju61r phvy n75nrj-gnored?

  An object that is thrown vertically upward will return to itp63+ r. yqjela mizkljw8 /t.y;n2,ens original position with the same speed as it had initially if air reslenja ,yj36n. y./rkq let m+z2wi8p;istance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero accelew:u mv -b649uutzo wpc6optyf.l9 +i1ration at the same time.

  An object can have nonzero velocity and 3pf8me8sg)w9 xzmsc(zero acceleration at the same time.

  An elevator moving from the second flo 5qk08t hxkls5or to the fifth floor making no stops along thxlsh5qtk5 0k8e way has zero acceleration all the time.

  A rolling ball moves frche66s y2 z -vv+n,twzom $x_1=3.1 \mathrm{~cm}$ to $x_2=-6.3 \mathrm{~cm}$ during the time from $t_1=2.3 \mathrm{~s}$ 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 $t_1=-4.9 \mathrm{~s}$ is at $x_1=2.8 \mathrm{~cm}$ and at $t_2=3.8 \mathrm{~s}$ is at $x_2=7.7 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete j7 tvryrxn 7-2laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.5 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 88 m awynfizd 5 c0o1.o*1hpj ay in 13.2 s. It then turns abruptly and gallops halfway back in 4.5 s. Calculate (a) itso5jc y f1d0o hipzn1*. 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 gc:ex)xe4e5 dy7c6v q$11 \; m/s$ to $24 \; m/s$ 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 fromf qzq7zg nz5ho6:t .5x $18 \; m/s$ to rest in a distance of 60 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speeddw4l mzd v g-wmh3oa+.j/-, il of $31 \; m/s$ 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 the blocks to essentially top speed abou u4tj0vxr26h8 j l9ttjt xu49tvj jt 028jhrl6t $11.3 \; m/s$ in the first 11.6 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 from a speed9kv:j+r,4 x rwcki jw:)o4 8hez dyl(y of $17 \; m/s$ to rest in 5.76 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. Assumg-:1 pbj /dxh;xy 7 qfoy/(yusing a decelerati uqh;y/17yxf g/jb-d y so(px:on of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truc;5k+d p99(rhikmn h cw; ez+xjk 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 thw/.vy2jros x0e 10,000-m run in less than 30.0 min. After exactly 27.0 min, therry. x/wso 2v0je 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?    $s$