Suppose that an object travels from onghak (*a.nvc 2.dsjo7 e point in space to another. Make a compari(7g*s2cahdvoj .n ka. son between the displacement and the distance traveled.

  When is the average velocity of an object equalkvdnc+)gao.gn.6i/ u3 feu6 j to the instantaneous velocity?

  A new car manufacturer advertises that their car can gox ynv2 t0.9h r*5q e9bjz5kacf "from zero to sixty in 8 r5e2t9hqbz0jvx fy 5an ck.9*s". This is a description of

  An object moving in the +x axis experiences an acceleratiz6q sy9:.nq dlmuzh23on of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction)net 4)e xb u1fm8k675t y/ opu6xhx,xl begins to slow down as it approaches a traffic light. Make a statement cox61x 7l),e8e4n6 m/p hf btxoxytkuu5ncerning its acceleration.

  Suppose that a car traveling to the West (-x b)t/mclm1t5 g direction) begins to slow down as it app m/1c)tt mbl5groaches a traffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statz 6r o5*bcpn47fcp wr6ement concf7po*cc4p wb6 rz65rnerning its acceleration.

  If the velocity of an object is zero, does it mean thak62f2zqm) l6guyw016 ccu if ot the acceleration is zero? Skw0lmu6 f2of62i 1guc6 cy)qz upport your answer with an example.

  Can an object's velocity change direction when its acceleration is constant? Su7w(+qc :beuyn pport ywby7eu( q:n+cour answer with an example.

  Suppose that an object is moving with constant acceleration. Make r*0zm y9)iier a statement concerning its motion with rrm)i e09r zi*yespect to time.

  Can an object have increasing speedlf.;b pc2wcd0 while its acceleration is decreasing? Support20c w. bfpdlc; your answer with an example.

  Suppose a can, after an initial kick, move1k98fqi cchkz*db 2:es up along a smooth hill of ice. Make a statement concerning its accel h9dizefb12*kc ckq 8:eration.

  Under what condition is average velocity equa+.aouon th w/7xu4h6nl to the average of the object's initial and final velocit .xnho/67w a+4 hotnuuy?

  Objects A and B both start at rest. They mz3gt nxv2 3a)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 thangmv xa z23t3)t of object B?

  Objects A and B both start from rest. They both accelerate at thrpgww- 1 a su+w4d:0d8c:mktk l2ct6xe same rate. However, object A accelerates for twice the time as object B. Wh4ca6gu +0dx -ctdmkplksw::1 t w2 w8rat is the distance traveled by object A compared to that of object B?

  When an object is released from rest and:-)pq syy,m:fegfdh9,3d zg-v9cvfkr3 v 5n q falls in the absence of friction, which of theks95q- frc: pzd 3yvdef3g)g v-y,hf9mqn,v: following is true concerning its motion?

  When an object is released from rest and falls in the zqh, /r mok5er+2j+es absence of friction, which of the following is trurez /mj2k+osrh+5, qe e concerning its motion?

  Suppose a ball is thrown straight up. Make a statemu .lj .urzb4b q ta:jc5b.8wd2ent about the velocity and the acceleration when the ball reaches the5j ubtl4 .z:qbwc 2bja 8dru.. highest point.

  Suppose a ball is thrown straight up. What is its accelerab(7 : 5carmvjmtion just before it reaches itsj7a:b mm cr(v5 highest point?

  Suppose a ball is thrown straialyr:r8 e*)czsgs. ) yght up, reaches a maximum height, then falls to its initial height. Make a statement about the direction:.)yz sgy)8 earsr*lc of the velocity and acceleration as the ball is going up.

  A ball is thrown straight up, reaches a m/ 36 epwq bo(gjsw6:fakxt4g (aximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the a g6qbp6:kwoge3x4(/st(w jfball is coming down.

  Suppose a ball is thrown downward in the absen,.1uyzhgt6f7 6smmbti0j0x p3bri p (s gf67h ce of air resistance. Make a statement concerning its x6t1 b7 z0rbsft,u6ggiph f m0sh.mi76( 3yjp acceleration.

  Suppose a skydiver jumps f 7zy oa k1xgi)8mx3hc-rx17kwrom a high-flying plane. What is her acceleration when she she reaches terminakyo-axw8izkh7 1r )mg37c1x xl velocity?

  A ball is thrown vertically upward with a speed v. An identicy,v) uteuk :5m.bs5 gkal second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second uk tymug:),55vebk.s 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 dro(w xj2rrqk;;etmc -13/ ltgc9 +ahfjehb 1k )hpped from the same building. As time progresses, the dismrfj j29el11; taw)krqb(x/ g-3h c+hce;tk htance between them

  Ball A is dropped from the top of a buil4w a qdzexaba2tt,*0vfc m(.8ding. One second later, ball B is dropped from the same building. As time progresses, the difference in their . 2x det,taz*aw mq c80vab(f4speeds

  Two objects are thrown from the top of a tall building. Ovt bpz2 ag()21z 3szczne is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit sb3a2t)2z1(zgzvzpc the street?

  A brick is dropped from the top of a building. A .xn 9zaad- dar+ b.5p2ox1hb lsecond brick is thrown straight down from the same building. They are released at the samrpl1aoahx2 .-.b5 zax n9 d+dbe time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zerczb v.,m (5 f:aqywr8ro velocity in the +x axis. The position versus ,z.fvr c r(my5 8ab:wqtime graph of this object is

  An object is moving with constant non-zero accelerationnb. mip 86u,jy in the +x axis. The position versus time graph of y bj6 .m8,inupthis object is

  An object is moving with constant non-zero velocity in the +x axik;s 0*b myzffwe+(+bk.f n8at s. The velocity versus time grapsnft+ (kfmyz ke fa;.bb80+w*h of this object is

  An object is moving with constant non-zero acceleration0:.*n(r6c( 8rjqruw s cw bhcs in the +x axis. The velocity versusr6(8wh u wjqc0b rscr.:n*c( s time graph of this object is

  The slope of a position ver)jddi/ cr:,m osus time graph gives

  The slope of a velocity versus tim.v0 7ea)n-jmls uor;le graph gives

  The area under a curve in an acceleration versus time graph5d)39cdwcb q w gives

  The area under a curve in a velocity versus tumb3k6rvhzv8 uy w .7 8g(ru)time graph gives

  If the position versus25vms +(.fnke/ur1jv2gprwhv f g;q; time graph of an object is a horizontal line, the object i e ;/m;u+.g2f kgs wv5nhq2rpv1vfr(js

  If the position versus time graph of an object is a vertical line, the objectkj udy+ah 4 :kxe0i9d, isky,xk0e4 jh9+dud:a i

  If the velocity versus time graph of an object is a horizontal l):4lw 25ltrzgaz z .roine, the object i.wl5aoz: )2 z4ltzrr gs

  If the velocity versus time grapm5be,z1 (cagpa 1njxb c )j bw6a0(iz3h of an object is a straight line making an angle of 30 degrees with the time axis, the obje1(i zn3(a jmabb xceca65p wg ,)0b1jzct is

  An object moves 15.0 m north dx:qwsv0gc r2k*d18 h and then 11.0 m south. Find both the distance traveled and the magnitude of the displacement vecto*x r: wcd2g10h8 qsvdkr.

  A boat can move at 30 km/h in still water. How long wiler/( ne yg vycpv:auk8t2x/4;l it take to move 12 km upstream in a river f/vk;ygu(yx /8vap4etec2: nr lowing 6.0 km/h?

  55 mi/h is how many m/s? (1 c3pypz1lwvf z/ nwhw+ 7-- 5onmi = 1609 m)

  What must be your average q:*5 fannx uz8yh3c- a00pfwzspeed in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.vz67oj.py a3+i 9r -cyj e(hov0 km) in 2 hours and 57 min. What is the average speed of y7vo(j.jh-3+ypoivz 9r6eca the runner in m/s?

  A car travels 90 km/h. How long does it take f+lc; wp:z7yl+oogs v94+aynk or it to travel 400 km?

  A ly (light year) is the distance that light travels in:6rjy th9t;uzh lch. : one year. The speed of hj. tt;clr9:u6h: zh ylight 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 rhop(z,w fq5: ()xa: q eqh5zuhoad and you look to the side for 4.0 s, how far do you travel during this inatteae,(h5 wq)u5f: qxqz: (ozhhpntive period?

  If you run a complete loop around an outdoor track (40a*qfrxd ba2:upb+ vj-v2tz 3 10 m), in 100 s, your average velo+ 1f ju rvbadq*2xav23pzt:b- city is

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km easq3c./l i3nf nd q:7wpwt, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. Whaqn3:3qdlnfwp./wi c7 t was the bear's average speed?

  A polar bear starts a0guss(dfng5(bp.t d i/ w*v sny ;+5ypt the North Pole. It travels 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km westwsd *p5n(g0;gys p+yfi.vu(/ bdnts5 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 forbc44s (sau x8y 110 miles. It then starts to snow and you slo(bsa44 cysx u8w 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 at 80 km/h and 160 kmh/c ,zv0w7t qu at 100 km/h. What is the average speed of the motorist for this tc tz,/0wvquh7 rip?

  A motorist travels for 3.0 h at 80 km/h an5 :h5tij 5fp6gyfsv4dd 2.0 h at 100 km/h. What is her average speed fogfv5 5:hydj4f stip6 5r the trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north fee/nj.j(a :x zor 750 miles. What is the average spxj.aj/e :(z neeed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m:x1 bdo7wj-toqe3n4 aw6y h3e) 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 runnwhno3-36y 7o4tbqwx:j 1 eeader starts the final leg of the race, in order that the team A runner not lose the race?

  A car decelerates uniformly and comes lromw *t7te: ,to a stop after 14 s. The car's average velocity during deceleration was 38 km/h. What was the car's deceleration while s: otl7te,*rmw lowing down?

  An airplane increases its speed from 100 m/s to 160a3,iyi+csll + :7vo fv m/s, at the average rate of ovi+3,fli+l7c vs:ya$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h ackpn*),qs7e5sfwxmztf + 2v *zbibj)7celerates 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 acceler*z s0p0gt)xc xates 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 acce ji48gp3)q)dqjd68cx)af /ja epa 3ywleration qjdgfqp6ixwjea /ac3 84 a )dy)) p3j8of $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 4.4 m/s experiences a constant acceleratioghq a-9u, z*k*x1zfmvn of 9 *1xgh*q-kmf,z zauv$1.8 \; m/s^2$. What is the cart's displacement during the first 5.3 s of its motion?

  A bullet moving horizontally toeo;m9y ;0yf u;5okwvb the right (+x direction) with a speed of 314 m/s strikes a sandbag and pene0 o9mbo kyfuewyv;5;;trates a distance of 13.81 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carrier. zsub-n4h )cccbv( n z ;3stp,,It reaches a c,( us,tbc3n 4h s bz;pnz-)cvspeed 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 catapult?

  A car starting from rest moves w6bwb1w6c g z rdh6b09eith 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 itsauj 3kc mw(x :9+hu2dg average accelj 9 2h(kgx:a 3udumwc+eration?

  An object starts from rest and unt 9kv)s ,18( hkwszcxadergoes uniform acceleration. During the first second it travels 9.2 m. How far will it t s)(cw8az ,k9t1hksxvravel during the third second?

  An object is moving in a straight line with constant acceler6 m +1zwh iizp3nt.m,qna*q5gation. Initially it is traz6 n,atmp3+.q1 inzhi mq5w*gveling at 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 agu*-ythd) qj4f2. czvt $3.0 \; m/s^2$. 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 roadxsyj8.;gopc:vi x cat5 e-:r/ 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 turnsb qad)el*,uw 5/q jn/o green, a car that has been waiting at the intersection starts ahead/ *,/b)uwelaq nj5qdo 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 l0omxd + yyff5- 9bb0q12 m/s on the surface of planet X where the accele y0b-9+ybxd q 5ol0mffration 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 plnw3m4p:v g c/uoo4 a/6xib(xranet X where th:3xpwbiu ov /(xrnmag/o6 44ce acceleration 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 su 0sk sy;z7n la)x4rr0peed of 15 m/s on the surface of planet X where the accelerat00kyzs r7lrxs;n4u a)ion 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;-s3 6kvqdjmk where the acceleration 6 3dvjmkqsk-; 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 friend holds a rulpt 32*4k 5yjymdmso(uer between your fingers and releases it without warning, how far can you ex kypodmjm5 s24uy(3* tpect 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 fndh ag9h7ng3hf21 ro m xz:/5after 31m f5noznh2agh:3dgr/ hf97 x.00 s?

  A bullet shot straigfuff 2dwp86mef*d +6yht up returns to its starting point in 8 s. What is the initial w+dy*f uf 8p26f mfde6speed of the bullet?

  A ball is thrown straight up with a speed of 36.zkp(-.q5 nzk6rgv o. e0 m/s. How long does it take to return to itskv o-z( kz.qg6r p.en5 starting point?

  A ball is thrown downward from the ( hen )b20osgtwaw u- rykc:-:top of a building with an initial speed of 14 m/s. It strikes the ground afbc-o) g w:(0at-enurskw h:2y ter 7.6 s. How high is the building?

  A ball is thrown strai5 :oq7dur j+cnght up with a speed of 30 m/s. (only fill in numerical valuo j5+ 7ruq:cdne 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 u) fqk43r 4dtzzp into the air with a speed of 48.3 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 11 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 11.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velocitd7(ii/p*np;m c u (/a g)oxoppy at t = 1.0 s?

  In Fig. below, what is the veloc6 .oi ernf:ki8vipsfsm1 +y3;ity at t = 2.5 s?

  In Fig. below, what is tyst0-ty wm .e:he velocity at t = 4.0 s?

  In Fig. below, what is the vacv p;p nm19 j0t x2v0q1 bo1zo:as.kselocity at t = 5.5 s?

  In Fig. below, what is vd5oy9e s 8up0the average velocity from 0 to 4.0 s?

  In Fig. below, what i;dz qj-v e2xo4zotxzg n( o:18cti 2q/s the average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceleration a. jjs+scl ic+;;gj cx.t 1.0 s?

  In Fig. below, what is the accele/1i/gvaabr+m s,f5 is9uav) sration at 3.0 s?

  In Fig. below, what is the average acceleratixv) 8jzkw8 v:ion from 0 to 5.0 s?

  In Fig. below, what i mye 3oj8rb-3.5pmbnq y 4k2yms the average acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0:k+ex0p;3ss h5kl wa h to 8.0 s?

Does a car speedometer measure speed, velocity? {speb qm:y5 dete+-ed|velocity}

  An object can have aur hccf0sn0g9 d (1q;q varying speed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is p8/jmknh 9if:qositive.

  If one object has a greater spe(h tr w-9-tg rttq+x1eed than a second object, the first must have a greater acceleration.gq-+(hrt xtr wt 91e-t

  Two cars emerge side by side from a tunnel. Car A is traveling with a sp6v ow(+.w/egj+. bplmev u1 bheed 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 acce )v0z2vv 2nibs;juzjex;s c:0p 5ud s5leration decreases.

  A baseball player hits a foul ball straight up into the air. It lea-7,7roue-( wn:czeed ifdf)aves the bat with a speed, ew)-uneezfdcr 7a-d i:7f o( 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 its acceleration,fkm3( ;gfnd,x ayn1o, how does it ck; x3n,f,y(m g1dnfao hange if air friction is ignored?

  As a freely falling obj d *vdyd/n*ithjvf 5:(ect speeds up, what is happening to its acceleration, hown dd5/(*tj*dvfhyi: v does it change if air friction CAN NOT be ignored?

  An object that is thrown vertically upward will retumespf end v4w k;/8b39rn to its original position with the same sp9m3 d;be s/pfk vn4we8eed 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 arw k cnd;:o wm32 u6o,bl7u8qh4gql+ snd nonzero acceleration at the same time.

  An object can have nonzero velocity and zero acceleration at bys --ivd9a ;gthe same time.

  An elevator moving from the sec;8l . 7dysxo.: s.las3cdh1vhs s8ymcond floor to the fifth floor making no stops along the way has zero acce 7l s8ahm.dys8d cxlh:.ys ov;3s.1s cleration all the time.

  A rolling ball moves frob x ovw;u:h9oa.;k6acm $x_1=1.7 \mathrm{~cm}$ to $x_2=-4.9 \mathrm{~cm}$ during the time from $t_1=1.8 \mathrm{~s}$ to $t_2=5.7 \mathrm{~s}$. 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 $x_1=2.1 \mathrm{~cm}$ and at $t_2=4.3 \mathrm{~s}$ is at $x_2=8.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-milevit 2( maok )wp*sm,l46j6t tn ($1 \; mile = 1609 \; m$) track in a total time of 10.7 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 9 oiqk2qht2zww /s k67straight line, moving 96 m away in 10.2 s. It then turns abruptly and gallops halfway back in 4.7 s. Calculate (a) its average spw6zot2k 7hsqk2q9/ wieed  (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 frortog;qq) /yzg- p0chh9 31trjm $11 \; m/s$ to $24 \; m/s$ in 4.1 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 (f (e)4lhdi5zvccn4 p6wttc1 $21 \; m/s$ to rest in a distance of 69 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a sperj7de;s f(yb- ed of $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.1 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter can burst out of the blocks to essentially top sprhi pbbufuky 7f; ,6jd947t5 xeed aboutdfy,f4u5htu7rbk;67 x9j pib $10.6 \; m/s$ in the first 14.5 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 uniformbb pwixv3 (s)swy:fhv (4q9y9 ly from a speed of $21 \; m/s$ to rest in 4.53 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.fm(0ac*p7 (w 0ft afft Assuming a de(tpfwc7*f f00t af m(aceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goi;fgkk+17i/wv , fphztk(w g i4ng $25 \; m/s$ 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 min7g bg s*lfii*tx*fc/;. After exactly 27.0 min, there are still 1100 m to go. The runner must then accelerat 7* sii* ;/ctbxl*fggfe at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$