Suppose that an object trig9 ;ty7 a p1fa4hup ezm)xe))h1hdg4avels from one point in space to another. Make a comparison between the displacement and the dih 1;d)x 9y7z)h epg4p1 4at au)fimehgstance traveled.

  When is the average velocity ofihesd:6ty qvo15sad wey 20u/ 6,q3 na an object equal to the instantaneous velocity?

  A new car manufacturer adveruk9 i zbaq/t;mw7+7g z ixfoje /;r6+qtises that their car can go "from zero to sixty in 8 s". This is a u7f/kig 9+;mt bqox7rq /6e;az+i wjzdescription of

  An object moving in the +x axis experiences an acceyrbkz42d nu:1 lxia u,,gk1+f leration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begin23d wph4vp fe8s to slow down as it approaches a traff 2ed3w8hvp4pf ic light. Make a statement concerning its acceleration.

  Suppose that a car traveling to the West (-x direction) begins to slowwv+vb6 ar*n-hf+ u;uf down as it approaches aa*-b +frvvnu ;w h+fu6 traffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. :hy mp;f2phdj7/j z-aitjg/r+ *qh o1 Make a statement conc /yi+a* rhgt:1h hf; m/oj 2d7-ppqjjzerning its acceleration.

  If the velocity of an object is zero, does s k9hecty9lm,w -;5jn it mean that the acceleration is zero? Support your answer with9;k5lm n t9, ywhjsc-e an example.

  Can an object's velocity change direction when its acceleration is cookh(9 zug3:n jnstant? Support yourozu:9k(jhg3n answer with an example.

  Suppose that an object is moving with constant acceleration. Make a y35ixtevk )7o statement cotxye ivo)k57 3ncerning its motion with respect to time.

  Can an object have increasing speed while its acceleration is decreasing? w-lksv+rp7 y y:d7iw0Support your answer l 7y pw-i:rk0vywsd7+ with an example.

  Suppose a can, after an initi,hz8gr:qoo6z4tfdast n 23s :al kick, moves up along a smooth hill of ice. Make aa3gshdz::q 62ofrsotn4, zt8 statement concerning its acceleration.

  Under what condition is average velocity equal to the average o36od jvwtn ,*wrerp/ (f the object's initial and final v3*jt oe6/wvwr nr(, pdelocity?

  Objects A and B both start at rest. They both accelerate at the same ratvwv 22 b;ymf+3mxyf-xe. However, object A accelerates for twice the time ay v+v -m2yffxmx;bw23s object B. What is the final speed of object A compared to that of object B?

  Objects A and B both start from -9o.tytxn,..tw9og m lrjfr7rest. They both accelerate at the same rate. However, object A accelerates for twice the time as object B. What is the distance traveled by object A compared to ,r t.rwtfo-xg9ym9lo .tn.j7that of object B?

  When an object is released from rest and falls in the absence of--x;8tcb2cr pfywb)bd0+jco eu )ez 8 friction, which of the following is true p+cu cwb8d 0frtejo8)b2x ;eyb -)-zc concerning its motion?

  When an object is released fromri:zw/( s0 )j5b kjqtb rest and falls in the absence of friction, which ofw/jzbbr(i:0 st 5j )kq the following is true concerning its motion?

  Suppose a ball is thrown straight up. Make a h71 ,njkaypta6b)jvj ppuc* h) v.9)o statement about the velocity and the acceleration when the ball renp cu)*j .ykavpt6 )j,apvjho7hb19) aches the highest point.

  Suppose a ball is thrown st( j2 6mnvs)u,ugk7tzgraight up. What is its acceleration just before it reaches its hig(7u uvt z)ng6 2g,kmjshest point?

  Suppose a ball is thrown straight up, reaches a maximum height,20y+nen7ji a 4v 1jaug then falls to its initial height. Make a statement about the direction of the velocity and accelgn1vaj0y7n i+ e4j 2aueration as the ball is going up.

  A ball is thrown straighe)c1:ta zc5c;wfgs-a2b ld 1g t up, reaches a maximum height, then falls to its initial sfl ac );1ect21adg z5:cbgw-height. Make a statement about the direction of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown dqi ); bc33nfvmownward in the absence of air resistance. Make a state ;bqv fnmc3)i3ment concerning its acceleration.

  Suppose a skydiver jumps from a high-flying plane. What is her accelerathn v7uiuc :)(gion when she she reaches terminal veloci h(vnu: u)cg7ity?

  A ball is thrown vertically upwa;8ps pbj1kcwga:(qqlilmo .;1y hz5 4 rd with a speed v. An identical second ball is thpqqb(y4ghz . mpl1ka :si5 8;wocl1j;rown upward with a speed 2v (twice as fast). What is 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 o:bvuc(8x x ;,ti kaw+s38vjwof a building. One second later, ball B is dropped from the same building. As time progresses, the distance between the8,va3w;k osu+xi8(cwjt v:bx m

  Ball A is dropped from the top of a building. One second later, ball B is k rhr;9fa.rkv e1er6-g n:up-dropped from the same building. As-.h;aegrp-uk n f:e6v19 rrkr time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. O 3u s0a7xkqj4sne is thrown up, and the other is thrown down37xsq0ksu a4 j, both with the same initial speed. What are their speeds when they hit the street?

  A brick is dropped from the top 6c 14fh tny-zjgau s9+of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare the 6c 1n-j y49atugfs+zhaccelerations of the two bricks.

  An object is moving with constant non- zdc1vrxh(*v(bg+hdl+9l sa-zero velocity in the +x axis. The position versus time graph of this objehdd+vzgl1al vx((9cb* s -+rhct is

  An object is moving with constant non-zero acceleration in the +x axi q e*kkm90ek,vs. The positio*ke90kmeq , vkn versus time graph of this object is

  An object is moving with constant non-zero velocity in thg l,j6 5f bcy0)y;lqsf+- 5oz)sclekle +x axis. The velocity versus time graph of this objec),o y )lf0-zlqlb g+ 55jcfkecsl6s;yt is

  An object is moving with constant non-zero acceleration in the +x axis. The 0v6;kyqnj,l(rj 9oh6m+dof 5,ow c jzvelocity versus time graph o6 9;c qln,jw+5v 0(m y zodf6rh,jjookf this object is

  The slope of a position versus time omge 6sj:/f2(mvp 7nl v1i uobqoa6-9xz7w:jgraph gives

  The slope of a velocity versus time graph gm14ey64umr+ugpj n0cb b2+iiives

  The area under a curve in an ac/jde f8h0 uz.kceleration versus time graph gives

  The area under a curve in a velocitj-q1ea ls ;.s6ba e2ljy versus time graph gives

  If the position versus time graph of an object r20e et qqsz7an5nvz kq94ei68 2spt4is a horizontal line, the object iss7 qk2et6 p 8s2nra4eeqn v5iz0q4t 9z

  If the position versus time graph ory6)ec q1 )js flq81xdf an object is a vertical line, the object iss8dcxj)fq) y q r61le1

  If the velocity versus time graph of an object is a horizontal line, tvq-h 2paji)y) y 0h3jghe object 2y-ijjhp0y )a)qvhg 3 is

  If the velocity versus time graph of an object is a straight line makinlj8dc5e w7 wu5, mjju8g an angle of 30 degrees with the time axismu,d juwc5lje8w7 58j , the object is

  An object moves 15.0 m north and then 11.0 m u zl20.olr)h caa9k , rg,bv3esouth. Find both the distance traveoc. 9bkruz) g,hv,e0lr a 3la2led and the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. How long will it take to move 12 kk x t(x5q sti62kk2 9*nbax+crm upstream2 ri(xqsa5kxx k2+bktt n 9*c6 in a river flowing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609 m) 7w-5b8xazqju

  What must be your average speed in nd-jvwba 0p 4,f+*3t xt6ungcorder to travel 350 km in 5.15 h?

  A runner ran the marathon (approxim2-jzd-hbvsawh -9 8dxately 42.0 km) in 2 hours and 57 min. What is the average speed d-d-v jb 9zhxw-s8a2hof the runner in m/s?

  A car travels 90 km/h. How loh7is x ) b/54j0pnxc jw4ghrc)ng does it take for it to travel 400 km?

  A ly (light year) is the distance that light travels in :oe/-caurem) aqu0f 5one year. The speed of ligh rc: auoaq5/ef)eu0- mt 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 zd9z sk-bod4o(e4,lo road and you look to the side for 4.0 s, how far do you travel during this inattentive pe odsd(,o 4zz9 o4lk-ebriod?

  If you run a complete loop around angnq 2 (rhq),zgmmt d13 outdoor track (400 m), in 100 s, your average velocity m,n)( dq1rm23zqg tghis

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1 g8fhxa)f 2j*5uo-u x8w jpkb8.0 km east, then 1.0 km north, then 1.0 km west to return to its starting point. This trip takes 45 min. 2 u jg8ff*xb8oa 8k5jp-wxhu) What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, then k4whabq3 b51h1.0 km east, then 1.0 km north, then 1.0 km west to return toahqw53kh 1 4bb its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a weekend from school atg) s48fwpbe:w 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: )8ewpgbfws 4 far is your hometown from school?

  A motorist travels 1dn wy( /oxe5ms5n65iw 60 km at 80 km/h and 160 km at 100 km/h. What is the average speed of the motorist for th65w(eown sd5/n my ix5is trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. Whazi3k hojxxd*ci*0 8wbuy2.z 0 t is her averx*bj*3o8hyw2zu. 00zx i ic kdage speed for the trip?

  An airplane travels at 300 mi/h soutxwrjm q c(pdp4 3v;.;fh for 2.00 h and then at 250 mi/h north for 750 mile4df;pqj(3m w .rpxcv ;s. What is the average speed for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) for twi f:ewg5fybf;2qk-6 eam 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 5wg if:fbe6 2-qkw ;yfis 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 14 s. The car's average vik)*a o)a.nm 6 quebu7elocity during deceleration was 50 km/h. What wmqu7ia*)k .u)a ob6 neas the car's deceleration while slowing down?

  An airplane increases its speed from 100 m/s to 16ckypai050so .(u; nis 0 m/s, at the average rate of .npcs0 is;ikoyu 5a(0$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h acceleygi *; gn-kjp5keso. +rates 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 acceleratesq02wsw 5jom5b 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 cp jc3c-kf7*s makjl/n3rq 5/wl(fpi, onstant acceleration 5l,jf*wn(l-jp r/ qki7apcs3k/3mf cof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 5.9 m/s experiencz3jzeyp :4w1t7pbuse r-mx* ; es a constant acceleration of etu1b z4eyjpp73sr-* :w ;mxz$1.9 \; m/s^2$. What is the cart's displacement during the first 8.1 s of its motion?

  A bullet moving horizontally to the right (+x direction) with a speed of 43f( zj:if6ecx /0jnw (o1 m/s strikes a sanf(f 6 izc(:x enjjow0/dbag and penetrates a distance of 96.76 cm. What is the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is lad.sr-6 u hkn :m56t1cmj vs.mm+bqh.wunched from 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. .ksj-t h 1rbq.mn+ dumms6. cv5:6mwh Assuming the acceleration is constant, what is the length of the catapult?

  A car starting from rest moves with constant acceleyk 7ak/- j0dccration 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 iy3eee0tn*bp49q6d g2ra4 gt ets average accepeb6d t9t a4n 0e2ggyee*43 qrleration?

  An object starts frombxu2uzc +x162r+ tyyw rest and undergoes uniform acceleration. During the first second it travels 9.5 m. How far will it travel during the third sec2c x+y 2+r 1buxywut6zond?

  An object is moving in a straight line with constant acceleration. Ini.kt8 n qrmjpw*ivrul)* z+ a3,tially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How far does it move during this tial)qrik,8m* t. * pjzvnuw3+rme?

  A car starts from rest and atzv) jz)7rjhbx 5(mc: ccelerates 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 /,*ce wggy(i*7zkh+copj- zw 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 waiting at t8nuy lhe +ty09dvzv z 1t(2si1he intersection starts ahead with a constant acceleration 0+2tts (hy8 ueln19v idzv1zyof $2.00 \; m/s^2$. 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 sp4nt4 l2oii*og eed of 12 m/s on the surface of planet X wher4ln i2iogo*4 te the 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 sppmt sun.dgt c7 (8h6i5eed of 12 m/s on the surface of planet X where thett.8cip(hu657 n dm sg 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 speed of 15 m/s on the surfacbuj. 8alje-i- e of planet X where the acceleration d- ji lu-jbea8.ue 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 u6me4*o h8 zko;*1nr4mxwah er pward with a speed of 14 m/s on the surface of planet X where the accelerw*o r6o*zh841a rx hmm4 knee;ation due to gravity is $3.5 \; m/s^2$. What is the speed of the object after 8.0 s?

  Human reaction time is usuallyzzf0wu+.7bn wq.2 udk greater than 0.10 s. If your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fall before yow. nubk 2qu0+z7 .zwdfu catch it?

  A ball is thrown upward at a velocity of 19.6 m/s. What4-t2p9f l ws0hco.wjz5ok0jk7 xbo3s ;juqb* is its velocity after 3.00 s0bj o7* s3 p2kbj;sztou05.ohj-x wl k4 9qfwc?

  A bullet shot straight up returns to its starting point in 9 s. What isfw 29. j7nuyjl)z abl- the initial speed on- l7yzu). jawbjf2l9f the bullet?

  A ball is thrown straight up with a speed of 36.0 m/s.aud;lc vfi3wf 5)w/ c0ig ;f-h How long does it take to return to i f3;wlgcfif5/0;- )ivcudah wts starting point?

  A ball is thrown downwauks15ex1(do d rd from the top of a building with an initial speed of 6 m/s. It1x dds(51ok ue strikes the ground after 7.0 s. How high is the building?

  A ball is thrown straight up with av rnsv :js-;.r speed of 30 m/s. (only fill in numerical value in th.vs:vr -; jsrne 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 (zkyvp 9z; 8rjof 49.2 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 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 thew(n oz)12hj pr(hd0 tqa 1iu0j velocity at t = 1.0 s?

  In Fig. below, what is the velocity at t = 22(h3)b piw2s *c e;es8re c09sedefaw .5 s?

  In Fig. below, what is the velo5w 8wpf7/tq /+jcds4g6ksk cy city at t = 4.0 s?

  In Fig. below, what is the velo: x6+/d u3vo,zctb) a7kojsomcity at t = 5.5 s?

  In Fig. below, what is the average velocity from 0 tor+qn; bv/e q9r 4.0 s?

  In Fig. below, what iy. (0dvby .cnea -xrejk3 ef3;s the average velocity from 0 to 6.0 s?

  In Fig. below, what is the acceler juw:2zl; /fvnokfv,, ation at 1.0 s?

  In Fig. below, what is the acceleration atoay - i(.fg*44z fxlno 3.0 s?

  In Fig. below, what is the average acceleixud2 p0i c3-kslg s13ration from 0 to 5.0 s?

  In Fig. below, what is the ay 8 wtriyn* u2k9wb+c 45/qnhbverage acceleration from 0 to 8.0 s?

  In Fig. below, what is the 0 ur7b3z qohhwqr,e58 displacement from 0 to 8.0 s?

Does a car speedometer measure speed, velocity? {spe*kfnfc)b98fvqb ;1.il:b8jsk/6 9ge x qk cgced|velocity}

  An object can have a varying speed if its velocity is consta;d sk(ssc:5g-hx-t8 2u ocjetnt.

  The velocity of an object can be negative when its acp/0 /:ajr hlbqb2+ lwbceleration is positive.

  If one object has a greater speed than a second obb).hobr 7kw8xwe-o3 tject, the first must have a greater acceleratw obk7t e8-r bx3o.hw)ion.

  Two cars emerge side by side from a tunnel. Car A im k94b9kq;c o7 l/dyfhs 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 acceleratxb o3jxn 1w2dkrd0q/ 1ion decreases.

  A baseball player hits a foul ball stu 3o2uf. t7t odykbg61uk.2y,nwsea-raight up into the air. It leaves the bat with 3u2n.6tawdo u b.7 -ykyg2oe f,us1k ta 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 spk7 5oy-iy kexv;,a hf ;or.1ajeeds up, what is happening to its acceleration, how does-;.ij;orfyv,a 7kk 5o1yxaeh it change if air friction is ignored?

  As a freely falling object speeds up, what is happening to ifw1p5w 9wgb w9ts acceleration, how does it change if air frictiof1wwpwbw 599 gn CAN NOT be ignored?

  An object that is thrmg 3nb b670ws 0jdo:z3a5bmwt own vertically upward will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance is appreciable, how will this result 6bmabgwj03t03z7 sb5 odw:nm be altered?

  An object can have zero velocf2rynd0m4xrtw a8 gr(h** m 2nity and nonzero acceleration at the same time.

  An object can have nonzero velocity ant gogz);9 )yay. 4cqgxs./0ios 9abg nd zero acceleration at the same time.

  An elevator moving frosg:u ggtg269j m the second floor to the fifth floor making no stops along the way has zero accele ggt u296s:gjgration all the time.

  A rolling ball moves fromei(/ 1kzyi/b:ux9 max $x_1=2.0 \mathrm{~cm}$ to $x_2=-7.3 \mathrm{~cm}$ during the time from $t_1=1.0 \mathrm{~s}$ to $t_2=5.2 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.0 \mathrm{~s}$ is at $x_1=3.3 \mathrm{~cm}$ and at $t_2=4.4 \mathrm{~s}$ is at $x_2=7.7 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight 8. jmd/5mum xccomplete laps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 7.9 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 stj3p/+fqfbci;4 +k :)w 8; eiviwcmfkjraight line, moving 110 m away in 13.4 s. It cff bcepkjv 4ii+ ;mw8 k3:+if;jw)q/then turns abruptly and gallops halfway back in 4.5 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 frodh9;v8sqww9a m $12 \; m/s$ to $24 \; m/s$ in 4.8 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 cbx)gzh 1 jlc*z6en;efe5*hk5 q 2 x2e$23 \; m/s$ 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 ofq 2odxebgw ho(dee4/ :m4.+jo $29 \; m/s$ 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 outgznz8d -ghx a2+ia ulqadw,* hpk:05 8 of the blocks to essentially top speed abou:5 pha q -xdn*+8adh,glu 082igzk zwat $11.2 \; m/s$ in the first 13.1 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 uniformly fc yd i5dbm-k z:wjk*rr(2)g ze.+ ny4erom a speed of $20 \; m/s$ to rest in 4.29 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. Assumingxy /fs2ekjcsoq8g.5eq+k vd 2-1 gu6o,1kubh a deceleration sco2gkug8 duokbexvf+y h./25,16j e kq q1s-of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck goi4 a w1;yl* zqzr:i i1zdkp)r)yng $25 \; m/s$ 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 comk:1 20 yb.giluwcn;yrplete the 10,000-m run in less than 30.0 min. After exactly 27.0 min, there are still 1100 m to go. Th2i:u0 r1 g kbly;wcny.e runner must then accelerate at $0.20 \; m/s^2$ for how many seconds in order to achieve the desired time?    $s$