Suppose that an object travels from one point in space to ano- 91zjj;vipz 7ekli tm;m 2y,nther. Make a comparis-j;ikpjl v2z91inyme ; t7z,m on between the displacement and the distance traveled.

  When is the average velocity .xdjie2y e n4vcz(kj7 ;9u nq2of an object equal to the instantaneous velocity?

  A new car manufacturer advertises that their car can go "from zero to sir c0i5p6urmr vzlq/i9 va*/ei- dqljx,+ub+2xty in 8 s". This is u5q+icpv*e rva6 u,/9j+q0izi2-l/drrb m lx a description of

  An object moving in tha31h7 -erbw wee +x axis experiences an acceleration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car traveling to the East (+x direction) begins to slow downgy,r epfp).wgw,+g r6gwhw(vblf+- 3 as it approaches a traffic light. Make a statement cgp v6+)eb-ww,gl+ y rg,r.f3gpfhw( woncerning its acceleration.

  Suppose that a car traveling to the w7wxnb6fea ua-p a t:tif6)zj1h+;( wWest (-x direction) begins to slow down as it approaches a traffic light. Make a statement concerning its acceleratio xwa 6uf;bat -6iw1(f t+pajezw 7nh):n.

  Suppose that an object is moving with a constant velocity. Make v 9xzm f*f4+ksa statement concerz9mxv*f+s4fk ning its acceleration.

  If the velocity of an object is zero u5+m3g,i/m *4smwo:b eym wpq, does it mean that the acceleration is zero? Support your answer with3, biw/p+wm4s5gmeo m:mqu* y an example.

  Can an object's velocity change dii 0/ : ;vx/awqnyv2rwgrection when its acceleration is constant? Support your answer with an exax/a/vn2v ;wi:yrg qw0mple.

  Suppose that an object is moving with constant acceleration. Make u/b l1y9lj4iu vd5h6kqxl8*ia statement concbl4/ i 1q9 udvi6lxjlkh u*y85erning its motion with respect to time.

  Can an object have increasing speed while its acceleration is decreasing? Suppo4bh;bb d w0q-vrt your answer with h 0d qbwb-4;vban example.

  Suppose a can, after aj2 vbzdm 3a6su,p5y: nn initial kick, moves up along a smooth hill of ice. Make a statement concerning i5 2jnb6pd3 ,uamy:vzsts acceleration.

  Under what condition is average velocity equal to the average of p o+sx; fs 6aasddgj9;3dc7 r-the object's initial and final vsadorgp d;-ax+f ;c6d sj93s7elocity?

  Objects A and B both start at rest. They both accelerate at the saby(s5m m,k5 qkme rate. However, object A accelerates for 55m,bmkkqs y (twice the time as object 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 thyqd, t(a:.umcv 0.vebxw5z t*e same rate. Hoy u*50v v x,wca. (mbdt.z:qtewever, object 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 and fallhiw178k fslk3 0avfe9s in the absence of friction, whichi e af8s9hlf03vkkw17 of the following is true concerning its motion?

  When an object is rel) pj8dmb.ar0yro*vzaqp z c* v64 j/s8eased from rest and falls in the absence of friction, which of the following is true concerning vd*r m)op zp cj/b0*8aa 4v6y.qsrjz8its motion?

  Suppose a ball is thrown straight up. Make a zgwaj b 8a8p*hn41 h7l statement about the velocity and the accelera nhwh81l4a zj7 gb*a8ption when the ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration just be jkog: .t;7kkooib9kw/o+lu j.4c s-x fore it reaches its highestj-o:wo ikc.kok gs9+4k7/ ;ub. tlxjo point?

  Suppose a ball is thrown straight up, reaches a maximum height, thm5g5l8t wq +gven falls to its initial height. Make a statement about the direction of the velocity a5g vtqlw5m g+8nd acceleration as the ball is going up.

  A ball is thrown straight up, reaches a maximum height, then falls to its i f-f0- za7ruhwnitial height. Make a statement about the direction of the velocity and acceleration as the f-f0a ruhw-7z ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistx78 by. btgjhlb6*e.uance. Make a statement conl jh be.g7b8b6t uyx*.cerning its acceleration.

  Suppose a skydiver jumps from a high-fly1h/u3,cvo x8bwroj 4king plane. What is her acceleration when she she reaches terminal velocityoowxr,84 jk3h bc 1uv/?

  A ball is thrown vertically upward with a speed v. An identical second ball isd5cq9j* gudm+nd9d*g8zr: 5yvs d(a e thrown upward with a speed 2v (twice agqdrc95na j* u(gd5zs*yd+ddv m e9: 8s 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 t hkl;dpl tn-7m .78bad,cm5khjwnu 9 7op of a building. One second later, ball B is dropped from the same building. As time progressesn8pw -57h; dljkt mc,k7hnb9m.d7alu, the distance between them

  Ball A is dropped froiw.fd,(wsm-c +p) wqi m the top of a building. One second later, ball B is dropped from the same builiw)smw , +q(iwf.d-c pding. As time progresses, the difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown ut)ll1h.djglozhi,eq/*4 m d)fr5 ze 0p, and the other is thrown down, both with the same initial speed. What are their l)q m5 /,l*jt e.ieg)4 dz 1lrohzdhf0speeds when they hit the street?

  A brick is dropped from them6rle mn4h:toy 7: w3e3 6vvkd top 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 wn4ht:v7 636m: vm eor ely3kdaccelerations of the two bricks.

  An object is moving with constant non-zero4th-xu;df1ob-xqz -(d5 cu kv velocity in the +x axis. The position versus time graph of this (kfxc-ovb 41--tzu qxhddu5; object is

  An object is moving with constant non-zero accelcz9imo 1lr( yl qs9w+jz,j48rmn1 /xieration in the +x axis. The position versr 1ljz il9x(n9/ 1+,myis qc8ro jmz4wus time graph of this object is

  An object is moving with constant non-zero velocity in the +x axis. The v,hg namo3j;. telocity versus time graph g.j,;m n3t ahoof this object is

  An object is moving with constay k9k nybig2+j 9b/a4snt non-zero acceleration in the +x axis. The velocity versus time graph of9ya29bj 4n i+kkysb/g this object is

  The slope of a position versus time gra.z;;m8vwk c(e nw -6ncapjng3cb2 )paph gives

  The slope of a velocity versueedvb ig-,e x /h:bd1+bp5a6 is time graph gives

  The area under a curve in an accelerationz,pav802jkatb wq 3,n versus time graph gives

  The area under a curve in a velocky2-93 wz0ad4 bndotzity versus time graph gives

  If the position versus time graph of an object is a m7 qnn:lzj)hj2vo5+fhorizontal line, the object islf 2m7j5h)nvj o+:znq

  If the position versus time graph of an objpo2t6-mit qcg-hztj 90m3-qj ect is a vertical line, the object isc- 6q9q-2mjj - hz0pt3g tmoti

  If the velocity versus time graph of an 9dbzsu:ukg0v . d2vh6object is a horizontal line, the object dvhu9v kg:.su6 z0b2dis

  If the velocity versus timeokyq8qigo2 d6f 3f2l 2; uftf8 graph of an object is a straight line making an angle 2yof 83kidq2uf2 qof8;f6 gltof 30 degrees with the time axis, the object is

  An object moves 15.0 m north and then 11.0 m south. Find both the distanl v9pxl5 s+nr, 38loh 5tmi9sxce traverxsxll95v85o9p i3m+,ls nt hled and the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water. zrjgp5,,)nl; g)0:qsyieaez How long will it take to move 12 km upstream in a river floj z0, )qgz:a; lg5sypir,)ne ewing 6.0 km/h?

  55 mi/h is how many m/s? (1 mi = 1609 m)+a y* df cpnqt,422hwh

  What must be your average speed in order to travel 350 km 9hlix;1n00 u ixr.o umin 5.15 h?

  A runner ran the marathon (approximately 42tarvo,ffzc55h z x4k93;rs 8x .0 km) in 2 hours and 57 min. What is the average speed of the r zfz8x3 v4rx;5fks, 5rc9toahunner in m/s?

  A car travels 90 km/h. How long does it take for it t90 oqlwuvzsok-b + q97o travel 400 km?

  A ly (light year) is the distance that light travels in one year. The spetx5sn x7 ws4)0 o,h58stqgplt ed of light is4o0xw)5 s5 tnpt xs87q,stghl $3.00 \times 10^8 \; m/s$. 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 s lt,zl5 (d/favymi; 9and you look to the side for 4.0 s, how far do you travel z d,lti/ (lf5asvy;9mduring this inattentive period?

  If you run a complete loop around an outdoor track (400 m), in 100 s, your eo5lfo4m88z uqi :mq)4q uf -t, ;ibe 8x3lfmdaverage veld8:) umof4zmtilu-o mx488 b q qf,5ie;elf3qocity is

  A polar bear starts at the North Pole. It travels 1.0 km south, thr,f-* v:uywb dz+7hh)f gh( lten 1.0 km east, then 1.0 km north, then 1.0 km west to return to its starting poi( bz, y dhuwl*h-gfhv+:7) frtnt. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1wxa 98mihfthq)g7 0 d3pgm3(m.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 kmdgg9a(h0m p78)i3tw3fh m mq x west to return to its starting point. This trip takes 45 min. What was the bear's average velocity?

  You are driving home on a 2lqhu u p4a6 o0u 2:ee+sjw.vmd+xco8yb; h7g weekend from school at 55 mi/h for 110 miles. It then starts to snow and you slow to 35 mi/6+ljyc.qa2h2+oo e4b w7 8 dvm;guse:hp0xuuh. You arrive home after driving 4 hours and 15 minutes. How far is your hometown from school?

  A motorist travels 160 km at 80 cr x w5 vtib25c:cy 6hu8m9bf7km/h and 160 km at 100 km/h. What is the average speed of the motmi cr56by: 2bcw8u75 hct fxv9orist for this trip?

  A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is hejjgkgw;qa:qc.i68:j kwr .z-r average speed for the trip?qj6k8.j-:ick.;wz ggaj r:qw

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north f69gwd42j / oovau0y qtor 750 mwoqv 4y9a ug/o62 dtj0iles. What is the average speed for the trip?

  In a 400-m relay race the anchoms(unhd(j r9 4rman (the person who runs the last 100 m) for team A ca(u h49rndsj (mn 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 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 12 s. The car's ijdggka x) g *:,zdr7s8zut86average velocity during deceleration was 77 km/h. Whr)6j8kgt xd:gu 8da *gis z7,zat was the car's deceleration while slowing down?

  An airplane increase)k(e..mtsf- xh 5iciis its speed from 100 m/s to 160 m/s, at the average rate of e -f5sxt(i )i .hmkci.$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerat,:yx4 t q-;rg m(hnhzpes 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 r jdccce :0y.m4est 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 constant l j-qs;,fs/ehof1 n9facceleration of ss;f j1o/e f-qnhf l,9$2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity of 3.5 m/s experiences a constant acceleratim2flzlvw1+pg/up2v wh12 ,n 7tvyei4on of lvu 1fzlv2 miw,2w14 +2p/v epgnyht 7$4.8 \; m/s^2$. What is the cart's displacement during the first 8.3 s of its motion?

  A bullet moving horizontally to the right (+x dire0:. )gm)xg4 ttcpjl4j pot kj8ction) with a speed of 528 m/s strikes a sandbag and penetrates a distance of 76.94 cm. What is the average acceleration, ipt) p t.kmolj gx gj844j:t)0cn $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft carraiov v(9 )la;uier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is co voa; (9v)aluinstant, what is the length of the catapult?

  A car starting from res;+d(kmxeovna*5 v4h gt 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. 0oa8mq kl nh-)What is its average accelerati mak-h) q0ln8oon?

  An object starts from rest and undergoes uniform accelerat1v4 )hl*xr wyqvsq7o 7ion. During the first second it travels 5.4 m. How far will it travel duqql71v*o7ws x4h )v ryring the third second?

  An object is moving in +rn0vf4)qtswpht , j+a straight line with constant acceleration. Initially it is traveling at 16 m/s. Th+4vj,w spn)fr+ qtt 0hree seconds later it is traveling at 10 m/s. How far does it move during this time?

  A car starts from rest and phpt0: .b8 hf+3qyd kzaccelerates 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*7jn 6 2mq0bq6d vel.8nle daw 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, yb19e,uxnq3 m a car that has been waiting at the intersection starts ahead wiu3yb1x,me9n qth 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 withl. v;bntb2cp 3nv1iu+ ks7x;o a speed of 12 m/s on the surface of planet X where the accxnb uvlcipo2+;bk1 .ts37v n;eleration 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 jy* /2mg 7kjudihdc ho(,e.;z of planet X where the acceleg(eo;7.z diy hc*dk jh/2umj,ration 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 upwar/ 3qastm6 pn+ld with a speed of 15 m/s on the surface of planet X where the acceleratintpl+ 3am/q6son 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/sb6fh mz1xz; sxq,z3 2v on the surface of planet X where the accels 6vxh 2x3 mz1;bzfzq,eration 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 greatv xplvh0 6n,7 7:wdd)gkuos.ber 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 you cagx0 7.u 6,vbosn:ddh 7wvp) kltch it?

  A ball is thrown upward at a velocity of 19.6;szpsh,4+ abi m/s. What is its velocity after 3.0ps+h;z s,aib40 s?

  A bullet shot straight up returns to its starting point in 5 s. What is t9ipanu;tq 48phe initial speed of u4 a;np qipt89the bullet?

  A ball is thrown straight up with a j;c8q;p f shu :7obdr/speed of 36.0 m/s. How long does it take to return to its star /p:juo;s;drq8fbh 7 cting point?

  A ball is thrown downwaif :n hkk.hct z+x6w13rd from the top of a building with an initial speed of 13 m/s. It strikes the grwx3ki . kh:zch1f6+tn ound after 1.2 s. How high is the building?

  A ball is thrown straight uzfcch lk dq36bo6lu.0j z2 6/vq3hu;ap with a speed of 30 m/s. (only fill in numerical value ik fchoa6 26/6 q3dcljuhzvzq0b.3 ;uln 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 thzulzr: r3 -;bje air with a speed of 43.9 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 2 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 the velocitv :i,sj5 ;o *v:udjhwey at t = 1.0 s?

  In Fig. below, what is the velocityaw sb-r6n:;hpbqcb. v0u: 7gncx:d /v at t = 2.5 s?

  In Fig. below, what is the velocity at t kg64cw7ne vc6= 4.0 s?

  In Fig. below, what is the velocity at t = 5.5 sgx4r hri722q5 qnppk, ?

  In Fig. below, what is the average velocity from 0 to 49:6wey6h r vg5obtht 9.0 s?

  In Fig. below, what is th 9b,klg/,a2b;lkjc sf e average velocity from 0 to 6.0 s?

  In Fig. below, what is thl:smrt1wvc, 6 ,l jgc al49l9ie acceleration at 1.0 s?

  In Fig. below, what is the acceleration at 3.0 s?.g1 j 8y6lrf17uisoinfar f7s.3hqs/

  In Fig. below, what is the average acceleration from 0 to 5.0d 78tz)5 qyz*pi -bjowgh7h2m s?

  In Fig. below, what nrr.e; v73u gcis the average acceleration from 0 to 8.0 s?

  In Fig. below, what is the displacement from 0 t yns 5y-waj6flj3c,1 uue6e a4o 8.0 s?

Does a car speedometer measure speed, velocity? {spex7wdxqev .pwl/u6 01bed|velocity}

  An object can have a varying n d;,n/vxf+snzrn) 1espeed if its velocity is constant.

  The velocity of an object can be negative when its acceleration is positive2lek p 11lntk-.

  If one object has a great;6 gc5qx*z . dno 1ac6fc(wdller speed than a second object, the first must have a greater accelerationao6cdl* .ncdl; w5f6zcg 1qx(.

  Two cars emerge side by side from a tunnel. Car A is traveling witb;lwq/*lhb*4+o ::grngwjl llq ++dah 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 decneb5u1 .58bf -nakuvyreases.

  A baseball player him7 8 6ug,5l*kz zz;nc8sjbq2/qsqo p its a foul ball straight up into the air. It leaves the bat with a speed zs7n ji,;qlp*m cszgk8qzo85ub/ q6 2 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 .kk d -chje:p;1qtl9nduw.-aacceleration, how does it c-9 c-.we.jn ta;l p 1dhudqk:khange if air friction is ignored?

  As a freely falling object speeds up, what is happeniq iiq 4j/e+2i4y kyu6bng to its acceleration, how does it change if air friction CAN NOT be ignorei4 qkyqi2ey +j6ib/ 4ud?

  An object that is thrown vertically upward will return to its original positionsybb9l0(k; x1cxffu+*p 3 mc a with the samx u*;ly1mcpb kfc x ab+0(fs39e 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 zeror+vq 7 1fizfm- velocity and nonzero acceleration at the same time.

  An object can have nonzero velocity and zero a (yz(ahrktqa 1 w oyf ;)7lksv81s)zd5cceleration at the same time.

  An elevator moving f u j3 36nsowf4i8-)pihq anui4rom the second floor to the fifth floor making no stops along the way has zero acceleration all thenw iqi3p-j8unu6443so )a ihf time.

  A rolling ball moves from 1clleyiq *,t25r1pk*1ewfgg/( b wlr $x_1=2.0 \mathrm{~cm}$ to $x_2=-5.1 \mathrm{~cm}$ during the time from $t_1=1.1 \mathrm{~s}$ to $t_2=5.1 \mathrm{~s}$. What is its average velocity?  (数值)  $cm/s$ (only fill in numerical value please)

  A particle at $t_1=-4.1 \mathrm{~s}$ is at $x_1=2.6 \mathrm{~cm}$ and at $t_2=4.3 \mathrm{~s}$ is at $x_2=7.9 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete laps around a quarter-mile1 9.g j2k7dufrysqh2t ($1 \; mile = 1609 \; m$) track in a total time of 8.2 min. Calculate (a) the average speed  (数值)  $m/s$ and (b) the average velocity    $m/s$

  A horse canters away from its traineroih 3e640 i 57+ddfg y4ypykn2x-yicw1pgy p ) in a straight line, moving 115 m away in 12.7 s. It then turns abruptly and gallops halfiyy2pcw iy d4kgpn4fp+go -xyy h1)7 036ei5dway back in 4.6 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 from vlev f,4 .fdz8rk ,cw29, slzqzfs2c 4$13 \; m/s$ to $23 \; m/s$ in 5.2 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 fro asnb+qxxpw(;1z8 0y- ; wqlgbm $20 \; m/s$ to rest in a distance of 57 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a p7g;w+j 0wwjkspeed of $27 \; m/s$ for takeoff. How long a runway is needed if the (constant) acceleration is $2.4 \; m/s^2$ ?  (数值)  $m$

  A world-class sprinter c/(f. uqojw;q wan burst out of the blocks to essentially top speed about / qowf.w(q;ju$10.1 \; m/s$ in the first 13.9 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 speeq6g t kg1jk5*wd of $20 \; m/s$ to rest in 5.03 s. How far did it travel in that time?  (数值)  $m$

  In coming to a stop, a car leaves skid marks 92 m lo-dud a.hllal8qmwu h5*cr; z7*je)xm 68-vkrng on the highway. Assuming a deceledqm *u*aer.l )khucv;h5mljl -xza 6dw 8-78 rration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a truck g. tep;wcv81i poing $25 \; m/s$ 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. , lk1.jnpl4evAfter exactly 27.0 n.k,pllejv 1 4min, there 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?    $s$