Suppose that an object travels from one point in space ph1(:els a 0lugfl2s 43vfy8nto another. Make a comparison b( 8 fhnfl0py3au eg1 :24vlslsetween the displacement and the distance traveled.

  When is the average velocit3jj3,cs c;tyn y of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can godj7 g0 lri3-5ksn3vzu "from zero to sixty in 8 s". This is azjv gn5 0ki-dsl7 3u3r description of

  An object moving in the +x axis experiences an accelerationyx(sy-am) r;-)vvf if of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow down as im muj-b+)y7c.nhfbrxun,3r( t approachbumb(y3r h.-mjn +u c) rxnf,7es a traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to s 9on 7jf0e.qxelow down as it approaches a tra7. 0qo9xj efenffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a con2n kag 6gnam6driy0s6+e2d*lstant velocity. Make a statement concek 6ng+6r 2sgil2a06m de*y danrning its acceleration.

  If the velocity of an object is zero, does it x;inhuw:vf mq)w :3 i1mean that the acceleration is zero? Support your answer with h:u3wx f in1:m)iwqv;an example.

  Can an object's velocity change directif. n(0- jpncwion when its acceleration is constant? Support your answ.fw0p(nnj c-ier with an example.

  Suppose that an object is moving with constant acceleration. 3/+z . .:koeyftd nf7iakx4mn Make a statement ca 3y4:ffx7+/konz nk .itmde.oncerning its motion with respect to time.

  Can an object have increasing speed while its achx9w, self hb0zol7/(celeration is decreasing? Support your answer with an example.(l0hh o blef /zw,s9x7

  Suppose a can, after an initial kick, moves 3h, 6n s-o: zhrdt43piscfsu)j8.lxzup along a smooth hill of ice. Make a statement con3rz,s hu jhsp8cs34zdn i-.: lx)6ftocerning its acceleration.

  Under what condition is average veluznz0,t ;e xu0ocity equal to the average of the object's initial and fina0,e; uz utxn0zl velocity?

  Objects A and B both sngcn25 u a(a0ktart at rest. They both accelerate at the same rate. However, object A accelerates for twice the time as oc(ak5aug nn20bject 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 sa awp:n-(mlm1(g - upkwme rate. However, object A accelerates for twice the time as object B. What is the distance traveled by objectn -( am(wkml1p:pgw- u A compared to that of object B?

  When an object is released from rest z*b)r3srcn2x7 ni9qm,or)f x and falls in the absence of friction, which of the folln2 q nc,xs iorr39xzf*))7b rmowing is true concerning its motion?

  When an object is released from rest and fallu,p4 kawm(q3+oocps 7*yaey *s in the absence of friction, which of the following is true concerning its mwp3kqups+ (m, *c7yoa4 y*eoaotion?

  Suppose a ball is thrown stv(ef9avm+,z 2gywdt 8raight up. Make a statement about the velocity and the acceleration wgm2 ef(w9ya,dtvz+8 v hen the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just before ijue 1l. i,3: d( f8 jp*e (wettx1oqekf;cqk6ft reaches its highest p;.q:e* 8t1fwfxckejkqej t lu(e(d 13pf ,6iooint?

  Suppose a ball is thrown straii 4chphluqva 8qyz7q 4u/,h9j3bv 7u9ght up, 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 going u ,qh4h9y7uqb zpu8v9j4h/q7 aluivc3p.

  A ball is thrown straight up, reaches a maximum height, then falls e) uih4xuk,9n to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is comi,i4h u xeun)9kng down.

  Suppose a ball is thrownwyi a9lpr6r te:g1x9, downward in the absence of air resistance. Make a stateme69liax y9 ,rr:wgp 1tent concerning its acceleration.

  Suppose a skydiver j-f u5ce .cebn0 67ufuhumps from a high-flying plane. What is her acceleration when se u5fnfc-e0 u.ubh76c he she reaches terminal velocity?

  A ball is thrown vertically upward with a speed v. An iot f fw80pgq/)dentical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height/) wqofp8f tg0 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 B is dr6 9cqqo4v- w)gefr(zrd. gl7yopped from the same building. As time progresses,fr67wd-q.lq zrcg(ov4e9 g) y the distance between them

  Ball A is dropped from the top 5yw w4y.9,h30lvdmf kts 53 r:fy xmk*b zve(rof a building. One second later, ball B is dropped from the same building. As time progresses, the difference in their svy3fb 5mx43 w(rrl5 sty0w,kyvkdm9fz* . eh: peeds

  Two objects are thrown from the top of a tall building. One is thro*esvojdz2 r 23wn up, and the other is thrownso2vr3 *dz2je down, both with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a building. A second brick is thrown strai*zarep zz, fnp: 3ug3d zj:0w;ght down from the same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.j fg33p*:p; war, :ezzznz 0ud

  An object is moving with constant non c c5jdxu5rq9:wau +0iyh sy3-ee rzp 36gi71c-zero velocity in the +x axis. The position versus time graph of this object iy 51g5e-re9c cr3c0u 7:jxzusi6 wi+qh3 ady ps

  An object is moving with c( b5oar8kp+xa on+7tjonstant non-zero acceleration in the +x axis. The posiran+bx5ko j 8+oapt(7 tion versus time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. The v6;f.a9em57u8bova c ueizaov 31cl0 uelocity versus time graph of this object ia.c6aui b 3 e0e ovm159uv7afuzol; 8cs

  An object is moving with constant non-zero acceleration in the +x q5 cfxxd q6o)lqq*4s3axis. The velocity versus time graphq5f34qoqc)d qx6 x s*l of this object is

  The slope of a position f0hqi)/tef yjr(sa7 ;v),qfz versus time graph gives

  The slope of a velocity vers:,1bftcu49 p:iqzkn xe f 5xk(us time graph gives

  The area under a curve in a jqli)0vzx0 a--+y a snn6t6pin acceleration versus time graph gives

  The area under a curve in a velocity versus time graph gi,6rpw5xcu* y ives

  If the position versus time graph of an object is a horizontal line, the+ph:b,x0fz dp object izbf d 0p+ph:,xs

  If the position versus time graph of an object is a vertical line,.ye/9b.b:efh ( uikhr the object isf(h:r ehu..9bbe yki/

  If the velocity versus time graph of an object is)7ktt r*rkieh6l+un + a horizontal line, the object is7rr)tl+kuit 6n hke *+

  If the velocity versus time graph of an object is a straight line making an an*k 9pfb-q0 ;z-sii caggle of 30 degrzfi9ai qkg*;s0-cpb-ees with the time axis, the object is

  An object moves 15.0 m north and then 1s(omv m+0f j(obj h4.a+eq z0f1.0 m south. Find both the distance traveled and th( 4a0 e+qzbm+mvfs(.f jjo ho0e magnitude of the displacement vector.

  A boat can move at 30 km/h in still wat) :peojp 1ltqo rw0;jmf26 v:jer. How long will it take to move 12 km upstream in a river flowom : lq fjej120;r)6wv:poj tping 6.0 km/h?

  55 mi/h is how many m/s? (1 mi ga5qp1i hg66m = 1609 m)

  What must be your average speed in order to travel 350 km i4:vvsm+h(/ k tq+ lsq) x0vzein 5.15 h?

  A runner ran the marathon (approximately y4lw9 yh k:f4 *p:jdms42.0 km) in 2 hours and 57 min. What is the average speed of the rusj9pl my4 4yk*w:hfd: nner in m/s?

  A car travels 90 km/h. How lond0 x8g-e 8vgsld-2 gvtg does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in one year. xa l-)sok 3 7-leehp5sThe speed of le a3ok5lep- s 7)lxs-hight 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 straight road and you look to thx 80nx7 2wabad)ci0mtpwztb5 *:uos*e side for 4.0 s, how far do ydtow5xtza ):b w ixm072 n80abcp*u *sou travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in2ivg vzaoc8ojtn/,8o 2l )1oz 100 s, your averazo /v2oozv8j og li,n2 1tc8)age velocity is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.,tnaz j1;l +klu 1hf2l0 km east, then 1.0 km north, then 1.0 km west tjnzh2u1tl;lf1a l+k ,o 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 travelidvk7m177 v kws 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km westm w d7ivvk77k1 to 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 at 55 mi/h for 110 miles. 1 qp) mrchsga/);;jxkIt then starts to snow and you slow to 35 mi/h. You arrmhc/xp;k; r qs1j))gaive home after driving 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 i3q (j9u-a,iv kmau,s:hb8e jes the average speed ofk3(b - :ijh,eqe vum,sa9a8uj the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. Wharv0 f5y qhu3;st is her average speed for the truryq3f;0 5hvsip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/ 9 qhdcqnotx(-wff/c-c)3 j3b h north for 750 miles. What is the a9-3 /ncq (cqcbj- thdf)wof3xverage speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the las ilsr6yw*w* .bt 100 m) for team A can run 100 m in 9.8 s. His l6wi*bs *r y.wrival, 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 team A runner not lose the race?

  A car decelerates uniformly and comes to a stop after 13 s. The car's averag,jd:s)gg( 8ucogu lzml8;8xx e velocity during deceleration was 76 km/h. What was the car's deceleration while slowing dogju;szcdxl 8g8 :mgl,o(8) uxwn?

  An airplane increases its speed from 100 m/s to 160 m/s, at;pfp: d 4vx:yq the average rate of x4 dv pq:f;yp:$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the-cxkj;el 1xm *f;c/ law3t;n 9(vtglv 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 i)zh b+y71ohbu1rq-et :e f c/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 d6231(l menc+c i ma)1jnrcbmnub0j8 constant acceleratio ruadc+1b mbc2m6l08( jnic n)1j n3men 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 3.3 m/s experiences a s, 6qx1neoag*lg2j w -constant acceleration ofgelw*ng-s2oj1a6 qx, $3.3 \; m/s^2$. What is the cart's displacement during the first 7.4 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed kjfi) / (8fjc-evm5ri of 392 m/s strikes a sandbag an krie- jc)fj/i5fm8 (vd penetrates a distance of 25.29 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from2 5s9dmt 8jz1xb(rxlc 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. Assxlm zd51b( srcx9 2t8juming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant acceleration ofj g.wf- wwe exh5.b4*mrl:1ab $2.0 \; m/s^2$ 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 distanl 5fhu b/24+t vwhk0ywce of 200 m. What is its average accelerat/5wu0h2y4 l tb+fh vkwion?

  An object starts from rest and undergoes uniform acceleration. Dv*y9 *6kduud: l av ;xve6vnl;uring the first second it travels 9.3 m. How far will it travel during the thirddx* *d9n; lkleu6;: uavvvv6y second?

  An object is moving in a straight wwyq36 0nuiq14sjam, line with constant acceleration. Initially it is traveling at 16 m/s. Three w0,qyqsna3ui jw64 m1seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and accelerates unifcl m+4 6caqbj0ormly 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 at aboutwyhr) e3w q;xz3rr/r, $5.0 \; m/s^2$ 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 waitingqk4 z-k:yd .jn at the intersection starts ahead with .j:qkn-yd k4 za 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 ow1q:k*ckiv-o;qohv5p(a ,nohv: 5 n a f 12 m/s on the surface of planet X where the acceln,-hkai 5n aov1v5hp q*o(wo ;:qvck:eration 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 pllfhi *p v; /ti6 c8+lm3vf.jvcanet X where the accel vi vp c; f*6.h/8c+itlfmj3lveration 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 a speed of 15 m/s on the ,uv7 -vpz.o pasurface of planet X where the accelera7pv-a .pv,ouztion 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 X ss hvq e/3n;zlny y /b;u83ro)iw:p4g where the accelerationyu /;3 y;ongrwe384: b/vspl)zsihqn 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 fxml 69;u; xebyour friend holds a ruler between your fingers and releases it without warning, howxebm 69fxu;l; far can you expect the ruler to fall before you catch it?

  A ball is thrown upward at a vsi0 nu ddk+01celocity of 19.6 m/s. What is its velocity after 3.00 cdui0+0n 1sd ks?

  A bullet shot straight up returns to its starting point in 10 hs9xw( 1xqi0ds. What is the initial speed of the bulw(h1sxd i9xq0 let?

  A ball is thrown straight up with a spek zx gpp;y:t)o/xn/:n ed of 36.0 m/s. How long does it take to return to its starting pop:kp;nt/n)g/xo x: zyint?

  A ball is thrown downward from the top of t nb8:uj).f)vnqd9l8fe/ mzcx v /f,ga building with an initial speed of 27j.lnbd n zt8fq:f f)8,/ umx/eg9vc )v m/s. It strikes the ground after 3.1 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only 1gjk4+o;8e.ifo s* bt0oel aifill in numerical value in tho;f8ebi 4s iltko1 +0.ejao*ge 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 ah-diy2qw+8ka+w8d7m x-nvhe2 o z+xn speed of 29.3 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 3 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-j88 bchnu9dc1e m( gm ui av))0kpm7i the velocity at t = 1.0 s?

  In Fig. below, what isycm+lmps)e( yh8 jwd jo+f :(cku9;wir7 m o/+ the velocity at t = 2.5 s?

  In Fig. below, what is the ver 0jltg)bp *1alocity at t = 4.0 s?

  In Fig. below, what is the velocity at tj. *u ,nal-bson,j oz8 = 5.5 s?

  In Fig. below, what is thr)t +d xb5)aate average velocity from 0 to 4.0 s?

  In Fig. below, what is the average velocity g.q c3t.hjjy a39vi4ofrom 0 to 6.0 s?

  In Fig. below, what dv;xsy*r d ( uv6s.(tvis the acceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0e8mosd , gi0ak70aa7)i7ay y i s?

  In Fig. below, what is the average acceleration frf- yb 8fnv,h)fom 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 to 8.0 sor nih6 py2+s6?

  In Fig. below, what igs,1,sldzy*p)o4w7x ip t 0wes the displacement from 0 to 8.0 s?

Does a car speedometer measurk;xz sbn60f 2oe speed, velocity? {speed|velocity}

  An object can have a varying spejx+;ow q5)h,m5ejefdsv* n r +ed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is positive).olinx /4ryb.

  If one object has a greater speed c9;cc6tr2l gjthan a second object, the first must have a greater accec6rg t l;c29cjleration.

  Two cars emerge side by side from a tkiv. f7ud/d p1unnel. 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 idz;v rg1rx-0m n speed as its acceleration decreases.

  A baseball player hits a foul ball straight up into the air.m/uqd (1jhdf. *jo dq- It leaves the bat with a speed hj.-/dufd ( o1dj*qqmof $120 \; km/h$. 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 its accelerationx88vx(,rctjt m+j ;lm, how (mrj8 t+mxjctl ;8v,x does it change if air friction is ignored?

  As a freely falling object speeds up, whatbcn kr(8fw46(by-pcs aw mm 6: is happening to its acceleration, how does it change if air friction CAN NOT be i-6bkc 6w8:r na bcyf(m4wms (pgnored?

  An object that is thrown verticab8)pr0x pm/ kolly upward will return to its original position with the same speed as it had initially pb o)k8mx r/0pif air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero acceleration axf1j3qwhu(9 x0 b x1uqt the same time.

  An object can have nonzero velocity and zero acceleration at the sam7u7m) i r1aqh.l.j cy;o*sqm ge time.

  An elevator moving from the second floor to the fifth floor ma7 ch 5eu1:brfwking no stops along the way has zero ac57uh1c rbe w:fceleration all the time.

  A rolling ball moves frmk1,cv9ray v:n2 t 8; ja:y9fybufdy,om $x_1=1.9 \mathrm{~cm}$ to $x_2=-8.6 \mathrm{~cm}$ during the time from $t_1=2.4 \mathrm{~s}$ to $t_2=5.9 \mathrm{~s}$. 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 $x_1=2.0 \mathrm{~cm}$ and at $t_2=4.2 \mathrm{~s}$ is at $x_2=7.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps pgfj9:r3-sav around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 11.6 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, movigoypj)7u gndsg . zb9h6h:.w7ng 102 m away in 12.9 s. It then turns abruptly and gallops halfway back in 4.5 s. Calculate (a) its average.u:yhophb76 wsj gzdng9 7g.) 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 frz +ppa5gc+ 1jmom $10 \; m/s$ to $22 \; m/s$ in 4.9 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 frouuydj4k-o: 1 ym $17 \; m/s$ to rest in a distance of 85 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speed ofann z;ms-.bfw+ 21 daj.* ogv-i*puyx $32 \; m/s$ 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 the blocks to essentially top speed alild b7 7v1,zyr zj0 df2de/z ng+1-esbou07/ 1 fyz7l2 beg s1drivl ed+j,z-zndt $10.9 \; m/s$ in the first 14.1 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 unif 7extxg n4ud.(ormly from a speed of $15 \; m/s$ to rest in 4.54 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leavrm/ii7sd)-*8wx5laq devrw ra 3) dz (es skid marks 92 m long on the highway. Assuming a dradzxw5 d wsr-*/vrq3am)li8 die7) ( eceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truckgo2 s/qytanhpa66 w:ap:: vq4 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 30.0 min. After, 6cvj g;wx1vp exactly 27.0 min, thepjg1w6, xvv; cre 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?    $s$