Suppose that an object travels from q5 1q fbcz k9 bmtwz17vk(6f4.d,hz ldone point in space to another. Make a comparison between the displacement(57zk dd 4c z,b9 qf11zvfwq lb.khmt6 and the distance traveled.

  When is the average velocity of an object equal to the instantaneous velociueyt e hw1i*2/ty?

  A new car manufacturer advertises that their car can gjel oaomg(-3zj)) u 4go "from zero to sixty in 8 s". This is a desg4z ()o jmaulje-3go )cription of

  An object moving in the +x axis experiencbb f0ij1d0b.ip7p91i sbh rv*es an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to f.:smt h1c / :oc4:;xbrphbyi the East (+x direction) begins to slow down as it approaches a traffic light. Make a statemenx1o:tfm: p h; hb4siybrc /.:ct concerning its acceleration.

  Suppose that a car tra9mrv( knrk *s5veling to the West (-x direction) begins to slow down as it approaches a traffic light. Mak kkm59*rnrsv(e a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a fv r payd.85+hstatement concerning ih+pvrd8. af5 yts acceleration.

  If the velocity of an object is zero, does it mean that the yxt,1i/b riv2acceleration is zero? Support your xvi2tr ,by/1ianswer with an example.

  Can an object's velocity change direction when its acceleration is consta ufcp(2uscq :8nt? Support your answ2(cs fp uq:8cuer with an example.

  Suppose that an object is moving with constant acceleration. M d ve21n;t+jyqake a statement concerning itsey1vjn;qd +2t motion with respect to time.

  Can an object have incvwn6y-l7 jw(kk5 wyg) reasing speed while its acceleration is decreasing? Support your answer witykw(k57ywn)g- j6 vlwh an example.

  Suppose a can, after an initial kick, moves upp jd )9tx5yw0a along a smooth hill of ice. Make a)y59p axw0 dtj statement concerning its acceleration.

  Under what condition is average velocity equal to the average gva;o y9,n:gr of the object's initial and final velo on:9ggvyra, ;city?

  Objects A and B both start at restl u*hy5fq;(f.e kbq2m. They 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 compared to that of object Bb( *umhy;qef2lfq .k 5?

  Objects A and B both star9vim i)x tyl.wbb:h6, t from rest. They both accelerate at the same rate. However, objb:xmitiwh9vy lb6, ) .ect A accelerates for twice the 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 an j- tfyshr:92cd falls in the absence of friction, which of the following is tr :t9j2fhscr -yue concerning its motion?

  When an object is released from rest and falls in t9vnw)nuv i lk*rd8x 2-he absence of friction, which of the following i-i2n8xw* ud vlrvn9k)s true concerning its motion?

  Suppose a ball is thrown straight up. Make a statement about tkutqp35, -4c6+o gmwx spnbqi*8ht(hhe velocity and tq(nq6-xhp8mso *45uwkp+g c3i ,htbthe acceleration when the ball reaches the highest point.

  Suppose a ball is thrown straight up. W 3z qn2xo4nhg6ntx6d,hat is its acceleration just before it reaches its high4dzhn3 xog6tqn,n6 x2est point?

  Suppose a ball is thrown sk a979,j6aa wb uvzgd,traight up, reaches a maximum height, then falls to its initial height. Make a stateabjvwa6 ,9u,97a dgzk ment about the direction of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reachessa4,s-d.chqt/uq rc/ pzo9c8 a maximum height, then falls to its initial height. Make a statement about the diruzohcq.4q cpr/,8- d9ctas/section of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Mako/e)5rl ) ol3hzg6wv(uo t q+ue a statement concerning its acceleue/l+qv 3h5 r)owtug(6o o) zlration.

  Suppose a skydiver jumps from a high-flyingdgj8er jf7-x)(2j7xixjicw: plane. What is her acceleration when she e8j7x7(cwgjrfxdii 2j:-j )x she reaches terminal velocity?

  A ball is thrown vertically upward wiua l3(k 7c3 ra;8heh8a,mmm7wpl1nioth 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 t rw( i kme7l,u;l hm8hancpama173o38hat 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 bui7 5i,adhf2nwjlding. One second later, ball B is dropped from the same building. As tim,25 anhjd 7fwie progresses, the distance between them

  Ball A is dropped from tlt/lu* tas q7bx0 jj)3he top of a building. One second later, ball B is dropped from the same building. As time pa j7u*l/q jlxt3bs)t0rogresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. :+v q r .qmc)hl3cjk+zOne is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the mzk v)++lcj3c r h:.qqstreet?

  A brick is dropped from the top of a building. A second brick is thrown strai)v8 jqlcx2nmj *(vq *nght down from the same building. They are vqq8 v cm*) jnx2ln(*jreleased 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 ac*wj77 i0wfq8pvokj1f* eb f 3xis. The position versus time grffo *7e81 jfkwp30c 7v*wbjiqaph of this object is

  An object is moving with constant non-zero acceleration in the* vg y0lkjl0 f7.dpzz*8l nq7m +x axis. The position versus tiv8 zq*07kpjm.0n* dl7fylzgl me graph of this object is

  An object is moving with constant non-zero velocity iwzq-q 4 d6nw1qv wx + va;l26kad:4wtin the +x axis. The velocity 6 4:wd2a; +wixvwzadnkqv qq 146l tw-versus time graph of this object is

  An object is moving with constant non-zero acceleration in the +x axis. z5s (yqmmi d/prj9-lfcyh72g 7 b4i* zThe velz/fdy -5 pg y7rl4* mc72i s9zijqh(bmocity versus time graph of this object is

  The slope of a position versus qurkb+3sf*w f3 o4:d kos5+cetime graph gives

  The slope of a velocity versus time graph gvhq0,y wq ikxz4kvp 7qf.867gives

  The area under a curve in an acceler: )5brsqd: bqpation versus time graph gives

  The area under a curve in a velocity versus 4eb+ol5 7 3ec xio(aqntime graph gives

  If the position versus time graph of an object is a horizontal line, wn clv.w) 0z-rfpeu-2 the object i- weuv wzf)c2n.-pr0ls

  If the position versus time graph of an object is a vertical lineic 6,5 sqszu-wtopq4 pl;a32 l, the object iss4co5qpw ,3slqzai p62utl;-

  If the velocity versus time graph of an object is a horizontal line, the objca/ ; ft/evocqcv/3j :ect isfv3: /e/ctcvo;q /jca

  If the velocity versus time graph of an object is a straights/w 7p98 gy pk+yzzsebri m.a,u:gu5. line making an angle of g.p 7 /5u.upa8+be9w:m izys,zsry kg30 degrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south.jx e)5wh .vkb ,eh:xh) Find both the distance travelhhk) )5 wxe.xj,e:vhbed and the magnitude of the displacement vector.

  A boat can move at 30 km/h io;lop2(4a t ,dnws xw5f k5gni22vr5l n still water. How long will it take to move 12 km upstream in agoid2k(tlsr p554 2x 2wnvlof, ; anw5 river flowing 6.0 km/h?

  55 mi/h is how many m/s? x3yj-nu nial8ly 4jz3b n0 0j4ri/ eq9(1 mi = 1609 m)

  What must be your average speed in order to travel 350 km in 5. qih pb5s48b lg rv8x*h/s(1ch1hy, dk15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. Wa b 4nl2vlq3:zhat is thzl:a 2q 34nlbve average speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for i8of- eqz zil28t to travel 400 km?

  A ly (light year) is the dist* iwehr;;x; ldance that light travels in one year. The speed of lighhde l;riwx;; *t is $3.00 \times 10^8 \; m/s$. 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 strazf;byg8g b +h;ight road and you look to the side for 4.0 g+;8 g zfbybh;s, how far do you travel during this inattentive period?

  If you run a complet bop 480d;cfya;n8 ewse loop around an outdoor track (400 m), in 100 s, your average veloci48ed8;oy a0pc nb fws;ty is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0be-dw/d uuy l(v:w8e/ km east, then 1.0 km north, then 1y: /b/wwude8 du(l-v e.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 Pole. It travels 1.x8 e+ lfz8oci7jr776aszzp l20 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 was the bear's averagjx7r 6olz7+8f8zli27s p aceze velocity?

  You are driving home on a weekend from school at 55 mi/h for 110 miles. Isn0 :6lro y )a/g be:,l+raqxrt then starts to snow and you slow to 35 mi/h. You arrive home after drivinsnll r go+rq: aera, ):0by6/xg 4 hours and 15 minutes. How 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 ave s+mgn406yejs l4c o8iw,w0yirage speed of the motorist for this triyw0swn m,ilecj+86ys44g o 0ip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her avbfm 65m( xdjek)1w h)derage spej6mwb5dd (1)hm) fx keed for the trip?

  An airplane travels at v ;f/ 8gal/su;yqu ti:300 mi/h south for 2.00 h and then at 250 mi/h north for 750 miles. What is the averauqg8f:vayus li //;;tge speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last :fj, z-cp c3 xae4o;lq100 m) for team A can run 100 m in 9.8 s. His rival, the anchorman for team B, can cover 100 maz4l c3e- j;fx oc,:qp 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 uniformly and comes to a stop after 9 s. fe:-evn6zc): yna*t jn 5ij( aThe car's average velocity durin 5(ia:tfyazcjne:v*je)- n6 ng deceleration was 74 km/h. What was the car's deceleration while slowing down?

  An airplane increases its sp +vo s(ee:1ji (cmx3cpeed from 100 m/s to 160 m/s, at the average rate of oies (cm (31p:cvjx e+$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acca m5 v0rcvx8p+u glmabufc(2:z/t) w8 elerates 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 and accelera d (3 (t(z k1v:x.cpwgxiyxq/etes 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 spe6 vadzk:xd4 -l ukw2eae91w5qeds up with a constant acceleration :ew dzx9 kau q64125wvdk-ale 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 6.0 m/s experiences a cob-g3ck gn g+-yty2 l2mnstant acceleration of y -g3mky2n-gb+gcl2t $2.4 \; m/s^2$. What is the cart's displacement during the first 9.2 s of its motion?

  A bullet moving horizontally to the right (+x dirav rl2 *;yge(pection) with a speed of 593 m/s strikes a sandbag and penetrates a(epgay l2;r *v distance of 12.26 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catap 1i./yhx3sue yc ml,ysurkcfo1 +647j ult 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 th ourlmcxf1e 3 j,u4s.1 isyy kc+hy/67e length of the catapult?

  A car starting from rewawm0hk q9. oq/mj. (i1:ig hcst 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 dis1sd4bup jy65+ ca2qbhpb,;)pz g4 rbftance of 200 m. What is its average acceb )1b,;bp+gb4f4qshzpar2ypu5d6cj leration?

  An object starts from rest and undergoes uniform acceleration. During the first6.oikkisgji6e 2q1 6p second it travels 2.1 m. How far will it 21jo. iike6pigq6k6stravel during the third second?

  An object is moving in a straight line with constant acceleration. Initiyy7lg) i lm:vz+ugk/. ally it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this z/+uyl):. imv ykgl7 gtime?

  A car starts from resv60d/ pom y(rwt 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 r m;.7 (f8olli+/qkf:c r *cize/ zkksdry road can 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 turns green, a car that has been waitinyh4ei c np8)1lg at the intersection stahy148e)ni pclrts 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 sp2 ld 9 -;zdxfp;.nzzws 78iawfeed of 12 m/s on the surface of planet X where the acceleration due nxdd 9l. pi-8zzw2; fws7 azf;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 planet X:p(x::uglo ejnsmr83g2 u 7v;xfy dr5 where the acceleraguvo udsm xg3 j;lf 72x :r5(rpe:8:nytion 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 p)5xgw( ck emf1c4zi- a speed of 15 m/s on the surface of planet X where the acceleration due to 4mki) 5ccz1xpfg- (we 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 upwa s61c) aopz,acrd with a speed of 14 m/s on the surface of planet X where the acceleaa6,p) zc o1csration 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 greate1pd *fma- foavo2;z4dr than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far 21dopmz -fdvfo a4;*acan you expect the ruler to fall before you catch it?

  A ball is thrown upward at a velocity of 19.f:c+(b88b hjio (s08ph omg qp6 m/s. What is its velocity after 3.00 sof88c0gp b p+8qm( hi(sbjo:h ?

  A bullet shot straight up returns to its startineopu*5p(l p9 2lwo6oou2us0l g point in 10 s. What is the initial speed of the bullet 0u59p2l upop(2o so*we6ll uo?

  A ball is thrown straight up with a speed of 36.0 m/s. How lonq 5l.- *bj4ho.o tsnttg does it take to return to its stnb4o.- ttj.o5s*hq l tarting point?

  A ball is thrown downward from the tog f.m/e zmo4e8p of a building with an initial speed of 20 m/s. It strikes the ground aftermeef8g. o/4 mz 7.7 s. How high is the building?

  A ball is thrown straigh l61xl *ceyzn-fkix xo ;b;,k5p,n*g1,b lzert up with a speed of 30 m/s. (only fill in numerical value iixfb*, yp,o; ,nl lzz k *nkxxbce1e65-rg1 l;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 straight up into the air with a speed of 23.9 ma.t3o0wh p4tya3pz :z/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 13 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 13.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocity at t = 1.0t kco;nek5 g+ wpxj1bn8 v/k+/ s?

  In Fig. below, what is the qd,8o: xddym 6velocity at t = 2.5 s?

  In Fig. below, what is the velocity atvi4 1-bx0 zd, pg 6i;xul9gffa t = 4.0 s?

  In Fig. below, what in1rsi)ygh 3l, s the velocity at t = 5.5 s?

  In Fig. below, what is ;0amg la) rqpl;k;xb5the average velocity from 0 to 4.0 s?

  In Fig. below, what is th167l csclf9oxga; hous2 .a7xe average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration ause:/u:fub 6 s:yl p:vt 1.0 s?

  In Fig. below, what is the-t7 nv:gmmf7d bv -w/mf 7zf1x acceleration at 3.0 s?

  In Fig. below, what is the average acceleration from 0 +h9ve) 8yx7fk9f 9ayd kcxqd6to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.0 s?w9du)zd jjabfs++)c *ld 9t7 o

  In Fig. below, what is the displacement fro:sae,weax xg;m: *js*m 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {speed|veloctymyyy82 ) 4i e:lmnp*ity}

  An object can have a varying speed if its v1ke )vg.a w up3;q(wbaelocity is constant.

  The velocity of an object can be negative when its acceleration is n1 xiv1d3o 7sppositive.

  If one object has a greater speed ty gr8ib xp84+nhan a second object, the first must have a greater acceleratnpr48yx8 +gi bion.

  Two cars emerge side by side from a txh :9.lyyzgv7ga v nf/wp/7w(unnel. 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 acceleration decreases.nj rg9u(*co kx 9t)5dr6apoyjqfo;* 3

  A baseball player hits a foul*8x3.x/mpiurlqk 28b hykr; j ball straight up into the air. It leaves the bat wx ;kumr8/xlb3. rkyqi28jph*ith 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 happening to izd bvv00cbt;3ts acceleration, how does it change if aic0bv3b0v d ;tzr friction is ignored?

  As a freely falling object speeds up, what is happeningzv:q +wd:mr* d to its acceleration, how does it change if air friction CAN Nmdrwz +:dqv :*OT be ignored?

  An object that is thrown vertically upward will return to its original 2m bfs,9,(cu fhge2v kposition w(vm,2 c9,euh fgsfb2 kith the same speed 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 acceleration at the/unh8 *ktr hj ) 7pebqrm4hg)6 same time.

  An object can have nonzero velocit/28m e3fh zebzy and zero acceleration at the same time.

  An elevator moving from t* gjhuu. 6t +7fq:9 zxefkkdc7he second floor to the fifth floor making no stops along the way has zero acceleration all th q*ezjct f.7 hux+kk ug7f96:de time.

  A rolling ball moves frjbo1 qw/mfkxy6. 5d8ijaj1o 1om $x_1=2.4 \mathrm{~cm}$ to $x_2=-7.1 \mathrm{~cm}$ during the time from $t_1=1.7 \mathrm{~s}$ to $t_2=5.0 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-5.0 \mathrm{~s}$ is at $x_1=2.9 \mathrm{~cm}$ and at $t_2=4.1 \mathrm{~s}$ is at $x_2=8.5 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps aaa k g:w6(*cqvround a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 12.1 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away fr-vbb3nf.-iulu (n5j e om its trainer in a straight line, moving 106 m away in 9.0 s. It u3 nb(-j b-f ivl.u5nethen turns abruptly and gallops halfway back in 4.8 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 frof- tcyc8t/*vu)te .av(tsc(h m $12 \; m/s$ to $24 \; m/s$ in 5.7 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 fror (q9n1uf22ok wk)bki m $20 \; m/s$ 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 mqi0k+fnu 7k w* )0bqjspeed of $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.5 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of th a00)t 6xdxhx72s rt,yjln3kve blocks to essentially top speed about y0txvtj720x rskhx,)3d na6l$11.0 \; m/s$ in the first 14.8 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 spee9 xel+(8g6-1k t9fhlmewxk ip d of $16 \; m/s$ to rest in 5.79 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m lotvx1e -4gc5 z)ruz2cy ng on the highway. Assuming a deceleration ofcr45vu zx1 )2ytz-g ec $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck gomhgbt z.ss/+di72j0ce, i j,ging $25 \; m/s$ 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 30.0 min. After exactlj cnw5g;p97on4oe5fc y 27.0 min, there are still 1100 m to go. The g75p n;94coc5f weo njrunner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$