Suppose that an object travels from one point in f3j:ta(3rv ptspace to another. Make a comparison between the displacement v:j 3 fp3r(attand the distance traveled.

  When is the average velocity of an object equal to the instantaneous velocu 5dxlp 9w/0faity?

  A new car manufacturer advertises that their car c deg,xja-e8of,.h c+qan go "from zero to sixty in 8 s". This is a descript,g eohx,e.a8qd-+ c jfion of

  An object moving in the +x axis experiences an acgbb w(yt:s3:eceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x directionomqg+g (:cd.i ) begins to slow down as it approach d+ggc.:om qi(es a traffic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direayl0se1 1+ iryc *r1dsction) begins to slow down as it approaches a traffic light. Make a statement concernyia e11r+yl*r sds 1c0ing its acceleration.

  Suppose that an object is moving with a constant velocity. Make a statement ck n,w9 .cb0 xa.um9unnoncerning its acceleration.kuxucwnman0.99,n b.

  If the velocity of an object is zero,m x3naim*f c.v,u i 2e1sxp:b3 does it mean that the acceleration is zero? Support v3,:1 x f*smiubpc2.aeim3 nxyour answer with an example.

  Can an object's velocity change directio4j4dt/iu z,j-oie 7jnbw.1wo n when its acceleration is constant? Support your answer wito t-b,1w/jei4uzij4d7jw o .nh an example.

  Suppose that an object is moving with constant accecmxz5,-; uuez leration. Make a statement concerning its motion withuz- mcz ,;5uxe respect to time.

  Can an object have increasing speed whi i;odn q oplp,79e 3dz644fnngle its acceleration is decreasing? Support your answer with an example.pn46 eo pglo ; dd4qn9i73zn,f

  Suppose a can, after an initial kick, moves up along a5)joun s epcp( 2x/gdm(p8tv : smooth hill of ice. Make a statement concerning its acceleration. n (2v t5ppg peoxcju:md8)(/s

  Under what condition ismk-ysp t g w7-aa/,ia: average velocity equal to the average of the object's initial and final v/aay - a i7mws:ptgk,-elocity?

  Objects A and B both start at rest. They both accelerate at the sa7ol2g3n a gybyj6k1 vt,/ f*ozme rate. However, object A accelerates for twice the time as object B. What is the final speed of ojf*t2 /,na76gl v y3z1obkygobject A compared to that of object B?

  Objects A and B both start fxy+mi lg wyr 4+2ig*.rrom rest. They both accelerate at the same rate. However, object A ar4 +mlg+*grywy2 i.ixccelerates 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 and falls iy9+fj :g ra amu6m,ph,vo(.af n the absence of friction, which of the following(f u 9 ,rm6yoh: ,avaj+afpmg. is true concerning its motion?

  When an object is released from rest and falls in the absence a3qsa9:bjr1 3. vzo ,t0idg)f:sqd7gug -rfbof friction, which of the following is true concerning its 3:o 3tbfg 9q 0)b,zv.r:f7 gqs-ur1saj iagddmotion?

  Suppose a ball is thrown straight up. p 0fxepd5--bu k l(lb-5lt )dh Make a statement about the velocity and the acceleration when the ball reaches the highlbp5hlu-dp lf- etkx -0( b5)dest point.

  Suppose a ball is thrown straight up. What is its acc7 xi p1j-ip8,xoi z-bheleration just before it reaches ithz-ipopxi81 i , -b7xjs highest point?

  Suppose a ball is thrown straight upbn/ (wgji0 1le, reaches a maximum height, then falls to its initial height1l(ginw /j 0be. 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 height, 5v + jguzp:zmal no 8go:44) n.:beafpthen falls to its initial height. Make a statement about the direction of the velocity and acceleratioop fn :4o.:g5:48 +g uzplm)jav anezbn as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Macfyq2iq ; f(2bke a statement concerning its accelerati 2 2fqb(qciy;fon.

  Suppose a skydiver jumps from a high-flying plane. What is her acceleration wheo(oybsrm6wfe:,r0 82wi 6zyon s,o f8obe:ow0y(myzrw62 ir6 she she reaches terminal velocity?

  A ball is thrown vertically upward wivdk *a-8.*hfeefvvs1va e42l a i2 oo;th a speed v. An identical second ball is thrown upward with a speed 2v (twice as fast). What ;v12i4*8.*k2esa a ovoefvaf d-h velis the ratio of the 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 of a building. One second l)vd **ut,dduczdk(q;/ep5 uj ater, ball B is dropped from the same building. ), dqj upzddc;t* uvd5 *(/uek As time progresses, the distance between them

  Ball A is dropped from the topfdi 0w8 gkw,i5 of a building. One second later, ball B is dropped from the same building. As time progresses, the difference in thei5dww0iik 8 ,fgr speeds

  Two objects are thrown from the top of a tall building. One is thrown up, an qaokv(ik2do 0g(cts.t*ld *n ;d5; odd the other is thrown down, both with thesv0;t; k5o(.( qdldodgcod* a 2*tnik same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top of a buildicm2+5yekfdg4;lyh4ca( pd zhp +89o yng. A second brick is thrown straight down from the same building. They are released at the same p z+yhyg844o kecad +5h ld9c2y;pm( ftime. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-ze 1wx+g.)sn zgwpp ;(iqro velocity in the +x axis. The position versus time graph of this object isg g1);x . inpzqsw(w+p

  An object is moving with constant non-zero accele)ysy z6ukb.*a 2c 3 h3ozhjy)sration in the +x axis. The position versus time graph of this object33hzya u b)yjc*sh62).sz y ok is

  An object is moving with constant non-zero velocity in the +x axis. The velocx*e -urox/azi tp,(8 h-ji; kmity o rpmai(,e ktji -; 8h/xxz*u-versus time graph of this object is

  An object is moving with constant non-zero acceleration in the +x axis2i4tyurvzn3 j18;/blguqhq 0. The velocity versus time graph of this object isqnj8ur3vi g/b4;u2 q0 1yzth l

  The slope of a position v-,*9et. xhorqu uzv vt)s tb3i1t7s+y ersus time graph gives

  The slope of a velocity versus time grapxsie45r*lf;oozbrr*4 2h 6xwh gives

  The area under a curve in an acceleration versus time graph tu) joe/:no un zv2h) rj6(q-f rvo2h/gives

  The area under a curve in a velocity versus time gb5+-wxq0(z qbuevw i.raph gives

  If the position versus time gra1p t/nybf.1tbph of an object is a horizontal line, the object isftp./bb 1tny 1

  If the position versus time graph ofs/9ocrau- kv3 an object is a vertical line, the object isrc-us 3avko 9/

  If the velocity versus time graph of an object is a horizontal line, the objectd4 41ut4tecfe 6ks h9 e1obo2y isc2o 491bo 6eus4tf14yetehd k

  If the velocity versus time4j eh5o4xs+1buqr 5g d graph of an object is a straight line making an angle of 30 degrees wrux45o1 s+b4 d eqghj5ith the time axis, the object is

  An object moves 15.0 m north and thsvwg+d 70+b4jpgu h4hen 11.0 m south. Find both the distance traveled and the magnub wv0 sgpg74j+h4d+ hitude of the displacement vector.

  A boat can move at 30 km/vsr ki3kkh9h +o1s 7x7um0d:lh in still water. How long will it take to move 12 km upstream in a river flowi h9kru+ 7ssk01kli:7o 3mh dxvng 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609 z9ycvmafb. .69 pecmkb4 yg6) m)

  What must be your average speed/r((1rrxouct3rzqmj 7: ka*t in order to travel 350 km in 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 :it0p kko (yrvn:su* 3efjhy; m-t:9qmin. What iet90q hv yf nu:(-i;k:mtp* y3sj:okrs the average speed of the runner in m/s?

  A car travels 90 km/h. How long does it take:,hf4w3r skj2p5xt dv for it to travel 400 km?

  A ly (light year) is the distance that f44 wq:ji6 +z)z mciqblight travels in one year. The speed of light iwc)z4q b+4:6 z jimifqs $3.00 \times 10^8 \; m/s$. 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 4.1hf ;4f*m:+y ex3nmg5lndc u j0 s,un+fm:41xe f gd53 h*myn c;jl how far do you travel during this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, you y5d*yxedz-7n kt1eq:r average velocity is1ykxd:z7d qe*-e y5tn

  A polar bear starts at the N6ao + 9w/xfmk+jzwql:orth 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. Thw:l69ow k+ja/m f qz+xis trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the zqm4 ze/x / d6akw qitau9h1:+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 takz/+q mqa4z1 id6uh/xa :tk9ewes 45 min. What was the bear's average velocity?

  You are driving home on a week9xyoit/nr)+iy:8 sed : qxr0og:.bd mend from school at 55 mi/h for 110 miles. It then starts tds8ro:/bx.niot 09q :+xegdiy:m ry) o snow 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 kbsgm zzv0bhv enw;:*s. za(q(v: u72 g 1svta)m at 80 km/h and 160 km at 100 km/h. What is the average sp g: suzzv g0*ba7w)tqv( . senva( 1bzsvm;:2heed of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 f14sy wf/3mw ap4cg1o h at 100 km/h. What is her average speed for the trcw4o3 p 4mgy1fwf1/asip?

  An airplane travels at 300 mi/h south for 2.00 h qgpreq ;/fp5(and then at 250 mi/h north for 750 miles. What is the average speed fo;(q e5/pqgf prr the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for kz28t/zs8(p w* :es+wedmq eq team A can run 100 m in 9.8 s. His rival, the anchormems q: 2(*zdp8 wwkt/ e+8qezsan 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 10 s. The cah bj* szc0k56c 1d: 5iocy,owfr's average velocity during decel,0j z c :5cobhidwy 15kcso*6feration was 56 km/h. What was the car's deceleration while slowing down?

  An airplane increases its speed from0t0fn .)c1uos,yd5xagn) ttfpdj *a( 100 m/s to 160 m/s, at the average rate of o)dutfa.j)tsn*nx(a c 510py dtf,g0$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate of o(mq-q nvfb :;$2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

  A cart starts from rest a9 3ikix5ec2tg+dl j6nv1 ,zwqnd 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 constantll:6,-pf3 ;vvyg09gqp vxt8 ;p hej ub accelerationx9vvfpubh t0-v jpe; y l8g6,:qpgl;3 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 2.0 m/s experiences a constant accele9g/ 5nz3 pgmuj:6vt4w q ojn+dration of 3jz/ nd5mw9 q+jggpnu4ot6:v$3.4 \; m/s^2$. What is the cart's displacement during the first 4.8 s of its motion?

  A bullet moving horizontally to the right (+iqpww.jkl 1qyi l.:*,x direction) with a speed of 498 m/s strikes a sandbag and penetrates a distance of 56.qk,p: wyl l.*i1i jwq.65 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 carrh zc( u4zrjv/kh tco+h*8cq 7 hd(p+*yier. It reaches a speed of 42 m/s at the end of the catap *hchc+yh k z(*j/4cz8qrup7(hd+ tvoult, and this requires 2.0 s. Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest.7o ya qv5fj)y d2d,cc 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 acwmyo9evw 02-7l-* *dpqx pfsf cvwqpml-0fw y-* 2feds9xp 7o *eleration?

  An object starts from rest and undergoes uniform acceleration8q(l2b x:9x6 x a qzv+m2ksj wh1brr/r. During the first second it travels 5rvz(x2wm1 a: j+ 92rbqx6qbr l/ kh8xs.5 m. How far will it travel during the third second?

  An object is moving in a straight line with constant acceleration. Initia73krg qae +27mj5rpk mlly it is traveling at 16 m/s. Three seconds later it is traveling at 1m23rgqe krj7k pa5+m 70 m/s. How far does it move during this time?

  A car starts from rest and acce8pasn,mj5i0vv z o,j2lerates 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 deceleratp4uk6 fcnl5 a*e 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,y x/wahva*, mm4wm .4t a car that has been waiting at the intersection starts ahead with a constant accyx waht wv.4*4am m,m/eleration 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 .:mcxbv .yc9a eti1d/ 12 m/s on the surface of planet X where c.9cbxyd/ tv i:.eam 1the acceleration 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 svu fa*m a634a8pkl.ofnjko,c 6. qy0purface of planet X where the acceleration yf6a0f .k,6oc aok 4.3v*uj8anpqplmdue 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 hq ;fe ldb5m(p(/kh4gon the surface of planet X where tf(b lq p;ed4( 5h/hmgkhe 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 t(/zs9 5+z;qzai fkjsmhe surface of planet X where the acc /9jzmf+z(5k;ssz aqi eleration 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 fr92-o gpr1 gi zyc,+ at+wzxh8xiend holds a ruler between your fingers az xo9hwzt i8-grxy+a12c+g p ,nd 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. What is its velocity after *aco 0on-z-6ukc qkysr:4r 4n 3.0scarq rk 6kcoz4-nynu 0- :4*o0 s?

  A bullet shot straight up returns to its starting point in 9 s. What rv-vjd+dk+x+ c+aa)oo 61i cvis the initial sari okdc d1)-ovvax++v6+ cj+peed of the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How l/j adz88cant 7ong does it take to return to its stcz8/7 adn atj8arting point?

  A ball is thrown downwardo p2 b lk, -brjafinzte/0452/)lzfrf from the top of a building with an initial speed of 29 m/s. It st fbzb jopn5/r /e)2r 4zt,2kfl0- flairikes the ground after 4.3 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (o.tu h j+) ct+gu0l9ijrnly fill in numerical value in the blank0ihtu jt)ugc.l9j+ +rs)
(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 33.9 m/s./cv glmlxkn:oc ,9ycd3(03 kc (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 5 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 5.0 m above the point of contact a second time.  (数值)  $s$

  In Fig. below, what is the velo)0l5jns(0 j imu l38kcu2tkhs city at t = 1.0 s?

  In Fig. below, what is the velocity at t = ircoq2mgo29 9.8;js )3zullgpuewq 6 2.5 s?

  In Fig. below, what is the velocity at.,d 8qohw,ld wl jd/6z t = 4.0 s?

  In Fig. below, what io+ +dhkt(*blws the velocity at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 to 4,su/1pjh*omx+nqui7 .0 s?

  In Fig. below, what is the average velocity from 0zj p h5cj.e- j+u)hn8g to 6.0 s?

  In Fig. below, what is the accele6n.af 3 vxwr* 1flbgy,- +efhsration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 s? )/)lb5f; isvzj*b22i aqklcao7gj6i

  In Fig. below, what is the average acceleratiow ,*eh- o4tmf2qp9ie bn from 0 to 5.0 s?

  In Fig. below, what is the average acceleration from 0 t. ff)oee 3w*kgo 8.0 s?

  In Fig. below, what is the displacement from 0 t1 q+1 d6pmieuxo 8.0 s?

Does a car speedometer measure speed,2us te9a)r cd, velocity? {speed|velocity}

  An object can have a varying speed if its veloci3m35wtx b;maz 0jc4y,h) nen nty is constant.

  The velocity of an object can be n4kxw sw7kj+le )g,gr +egative when its acceleration is positive.

  If one object has a greater speed than a second object,pe;g2(um( sbe the first must have a greater acceles ;2ugm (peeb(ration.

  Two cars emerge side by side from a tu52ttrztkc3.dqx6yt, nnel. 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 spe/c1i lw3 *xdc4+jhitywc.p q -ed as its acceleration decreases.

  A baseball player hits a foul ball 5x* gr4 pew;sestraight up into the air. It leaves the bat wipegrw;5s*x e4th 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 objecf81 tlnqgn o+.t speeds up, what is happening to its acceleration, how does it change if+.gnfno l8t1 q air friction is ignored?

  As a freely falling object speeds up, what is happenin7hz(p lpv2/,.qqf lcag to its acceleration, how does it chang c vz7pl h.2lf,/(qpaqe if air friction CAN NOT be ignored?

  An object that is thrown vertically upwar mt.g;9s+ vp3fyxbk6 yd will return to its original position with the same speed as it had initialyk.mfv; p+x b69sygt3 ly if air resistance is negligible. If air resistance is appreciable, how will this result be altered?

  An object can have zero v6b b3os.na9js uu ,2hmpx1w1uelocity and nonzero acceleration at the same time.

  An object can have nonzero vey+.r6ptgw8s 5hrq*q ww cr) ,flocity and zero acceleration at the same time.

  An elevator moving from the second floor to the fifth floowmb oxlgn /+,+r making no stops along the oml+ +bnw, g/xway has zero acceleration all the time.

  A rolling ball moves from xi rf35w0o b6sw.yf.l$x_1=2.5 \mathrm{~cm}$ to $x_2=-4.9 \mathrm{~cm}$ during the time from $t_1=0.9 \mathrm{~s}$ to $t_2=5.6 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-2.4 \mathrm{~s}$ is at $x_1=2.4 \mathrm{~cm}$ and at $t_2=3.7 \mathrm{~s}$ is at $x_2=8.3 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight j.k zt8i6y0e ucomplete laps 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 106 m 5/g v+sb ggj ;jg.;hvnaway in 13.1 s. It then turns abruptly and gallops half vj gbsg;j ;+./h5nggvway 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 fr bool4.++0oeh inz 9ezom $11 \; m/s$ to $25 \; m/s$ 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 o; 7o) claj4)emen :.lvyezw 5$19 \; m/s$ 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 ox julv/i1k z 50,uj8d4)d clxhf $30 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.3 \; m/s^2$ ?  (数值)  $m$

  A world-class sprintexapk9;tivbd1cr +8kj/3* v mqd. bs 2qr can burst out of the blocks to essentially top speed abou/v 9 s pi ka;3d1qkbr8*j.+tv2bqx mcdt $11.0 \; m/s$ in the first 12.8 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 fvkszz+ l5gab+6vj0 c6rom a speed of $18 \; m/s$ to rest in 4.59 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 obgpq3r rr/ 3bo ag;p0i1.0qpo hb*5b cb3y(vqn the highway. Assuming a b0rq3qar1pq/v bo* g;ri 3hgyb3b b(p.5p0o cdeceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trucka 9x529f j tz7sczs1,:px yero 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 30.0u)*dbi y4/ 1g a oho3fijsxj;6 min. After exactly 27.0 min, there are still 1100 m toy;hbx/3g if4aj)suo1*j6di o go. The runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$