Suppose that an object travels from one point in space to( i6v3wzuqadg3sh ),p another. Make a comparison between the displacement and the distance traveled,sp u6h d3(z a)gw3qvi.

  When is the average velocity of anlwvlf)lw ) g29jh+21kbb2nix object equal to the instantaneous velocity?

  A new car manufacturer advertixjwi4 2sm7 f frdqkbe :usywv9+s:b:u- (+2pises that their car can go "from zero to sixty in 8 s". This is a sdq:mibf-vuf7pxb ww s92kj+ uy4r2i(e :s: + description of

  An object moving in the +x axis experiences an aco6dr2n +oqew3 celeration of $2.0 \; m/s^2$. This means the object is

  Suppose that a car travelinoxhqlu: :m4dbnp+ u 59g to the East (+x direction) begins to slow down as it approaches a traffic light. d4mu+::q lnx u9hpb o5Make a statement concerning its acceleration.

  Suppose that a car traveling8 p(kkeki av.izh9u8n/86y gsd n2ze4 to the West (-x direction) begins to slow down as it approaches a tn/v 8dksz9ug.zp e84kn6i ke2ai8yh (raffic light. Make a statement concerning its acceleration.

  Suppose that an object is moving with a constant velocity. Make a state6l 15t./ qyndk 6 j9lbgf)lbywment concerning its acgy6bl/l dkf6tjnb9yq51w.)l celeration.

  If the velocity of an object is zero, does it meancjrc4yp4u1h+ .iny pcoq .l (0 that the acceleration is zero? Support yourp4cu1po y..(c0 4c +hrqlij yn answer with an example.

  Can an object's velocity change direction when its a m*1;gssa-l ducceleration is constant? Support your gma s*ld; 1us-answer with an example.

  Suppose that an object is moving with constant accelera xiy:jwf+a)q,tion. Make a statement concerning its motion with respect to )aqfxy +:,wi jtime.

  Can an object have increasing speed while its acceleration is decreasing? odna; vze,4jm0p 7q eh5b--ek Suppo e4-dqekoab0j 75,-nvh; pmezrt your answer with an example.

  Suppose a can, after an initial kick, moves up alon* )a 1+)vhk17cs xajs*mvc rmmo; .nyaa ob/z:g a smooth hill of ice. Make a statement concerning its accmz+ aabsxh7mm/v rnyj *cva).*1so;a1 :c)koeleration.

  Under what condition is average velocity equal to the average of the objectm po7rt)3hry z6+pt h.'s initial and )7tymprp3t hhz +.ro 6final velocity?

  Objects A and B both start at rest. They both accelerate at ac8ok)k m*0()(e5k 2o awyrtx;p*rs6mx cdg ythe same rate. However, objecmey y 8sk)ga0; p*m2wck *xrrk(o( ctd 65o)axt A accelerates for 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 the same /; n-2e6jl7wvx vaez+ggcxp) rate. However, object A accelerates for tw agxp2x+7vj 6v;l)wge/ecz-nice the time as object B. What is the distance traveled by object A compared to that of object B?

  When an object is relag/kb4xm 8+z leased from rest and falls in the absence of friction, which of the fokz+lx mb8/g4 allowing is true concerning its motion?

  When an object is released from rest and falls in the absence of friction, w so9og8 n(jjb-1pn j,fhich of the following is true concernj goj,8n9sj-(pb of 1ning its motion?

  Suppose a ball is thrown straight up. Make a statement abj(8d yr+lls( yout the velocity and the acceleration when the((s +rlyld8jy ball reaches the highest point.

  Suppose a ball is thrown straight up. What is its acceleration 1hk,-lz/4j :d e0rccmpqslo2 ukh97tjust before it reaches its hi1t:/cj4p0,r q udh -kmllhz2scko97e ghest point?

  Suppose a ball is thrown straight up, reaches a maximum xct9,4 zebrrt+a*5g e/7n sl gheight, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is b9,nx* 4 zarrg+s teg/c7le5t going up.

  A ball is thrown straight up, reaches a maximum heigh(h84i*f:kzg.w iwm bv ds-w -fmti8 o9t, then falls to its initial height. Make a statement about the d8g.v *(9stzwfb --:ihwki owdifm4m8irection of the velocity and acceleration as the ball is coming down.

  Suppose a ball is thrown downward in the absence of air resistance. Make a* +ma82np:v/nh x gqsa statem a:+pq*xg8ha n/mn sv2ent concerning its acceleration.

  Suppose a skydiver jumps from a high-flyind,sevd v j+-+)b-pywg g plane. What is her acceleration when she she reaches terp-vd+s +v- wj,) ybedgminal velocity?

  A ball is thrown vertically upward with a speed v. An identical secong2f72iv -twnj+4 zg.ptbhwp5 d ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the ma w27g5ghtzp 2w4fj+.b -itpnvximum 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 later, bal/x np9j8v0rg gl B is dropped from the same building. As time progresses, the dxr/ g0jgvp8 9nistance between them

  Ball A is dropped from the top of a building. One second later, ball B is q6 vcqfbf7s-+b)o5:p+;ox th eieliee87l / c dropped from the same building. As time progresses, tp8 oe-+o t xie+lsqi/q b6fhcv:e 7)e7c5bfl ;he difference in their speeds

  Two objects are thrown from the top of a tall building. One is thrown up, sl k3 ,cd *a 0,b qq7l5tdhwv0:ajra .orun9c7and the other is thrown down, b09l0slnrw5vquodc ha bj a ctd. ,7,kq 37r:*aoth 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 brina6y c+4 vmws;ck is thrown straight down from the sames navy4c6m w;+ building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks.

  An object is moving with constant non-zero h ))ivobu4, vqe0eu,.+ s,vf e:fivf+p5if ty velocity in the +x axis. The position versus time graph of this ovq)sv ve:tp5ef,,ih f ,vo4u0f +i feiy).b u+bject is

  An object is moving with constant non-zero acceleration in the +x axe332+,rehaeo 4a r/:adyl pliis. The position versus time graph of this object 2l/headierlra o,a43 3ye+:pis

  An object is moving with constant non-zers-8;wl 3 iwipro velocity in the +x axis. The velocity vers8-r3; wipw lisus time graph of this object is

  An object is moving with constant non-ze ; 5rbowteo.r+ro acceleration in the +x axis. The velocity versus time graph of this o5wr;rebo o+.tbject is

  The slope of a positi1,t wuv6qljcw 9 (a-4glrihd(on versus time graph gives

  The slope of a velocity versus t( d1v dw6z7 zn3 btko6rvyrt67ime graph gives

  The area under a curve in an acceleration versu3gge axt3pmgntm/ 6 y7(5tdnidks(10s time graph gives

  The area under a curve in a velocity versus wka 6z r/1crpty84,dotime graph gives

  If the position versus time graph of an object is a horizoi5kla96 k s/i dge7:fontal line, the object is /eg5o 69k:al f7idsik

  If the position versus time graph of an object is a vertical line, the -jkv+cm(s/5hjxbqkd l fr y:a1 v( /3aobject isf:v x khb-ca5/djq 3lvma(( 1yr+k/sj

  If the velocity versus time graye8 3m8l:rwk //qn x) bcy.rgzph of an object is a horizontal line, the object isly3 8m/br ex:8g/w.r)kqynzc

  If the velocity versus time graph of an objectiw.a-i3fs c d d3fge+. is a straight line making an angle of 30 degrees with the time axis, the obj. f -sid3.gfw+ eca3diect is

  An object moves 15.0 m north and then 11.0 m south. Find both the distance tkca5 vo3e1l/0od v6+ wlqge. travcw5o+el vt l6gdqek0o.1 av3/eled and the magnitude of the displacement vector.

  A boat can move at 30 km/h in still water.kjtqpiju dh 2(f6./9fff (r. 69hrwur How long will it take to move 12 km upstream in a river flowing 6.j(9 kt 6 hr2.r6qirf9.fdwfh(ufp / uj0 km/h?

  55 mi/h is how many m/s? (turd51 t0kjw6e 16fl(f/pu qe 1 mi = 1609 m)

  What must be your average speed in order to travel 350 km jb.pm ;+m e;kqin 5.15 h?

  A runner ran the marathon (approximately 42.0 km) in 2 hours g3j2pc3fl4p5- mc j paand 57 min. What is the averagejap-3pm4lc5fjg23c p speed of the runner in m/s?

  A car travels 90 km/h. How long does it take for it to o;rrgl9g) 5h( nk4-yj7ksiqntravel 400 km?

  A ly (light year) is the distance that*ype p7dj 7.g txmw*.3qy jj4h 5z)oec light travels in one year. The speed of light isp.e.h7 jcj3pm5 qxj*y*4ty )ewo7z d g $3.00 \times 10^8 \; m/s$. 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 s8i 1ejsw) lx4l+ pov6w3a:qjvtraight road and you look to the side for 4.0 s, how far do you travel during this vvsl6+ lj4qejwp: )a1o3i8wx inattentive period?

  If you run a complete loop around an outdoor trxhi1c/-4ue4 znzj)h g ack (400 m), in 100 s, your average velocity is4eix)4chnuh z1z/ gj-

  A polar bear starts at the North Pole. It travex;v 6 +ef6f wafee+2ub1m2 fxhls 1.0 km south, then 1.0 km east, then 1.0 km north, then 1.0 km west to return to its star2e fw h6xvbfuxm+ea;f +21ef6ting point. This trip takes 45 min. What was the bear's average speed?

  A polar bear starts at the North Pole. It travels 1.0 km south, then 1.0 km eau r 8f0p/kb7fpw tiw)1st, then 1.0 km north, then 1.0 kwt7 b0rkp8pwf)u 1f/im 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 weekend from schoo0hz 2 xitf.1kbl at 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 far is your hometown fro1 2zi k0bf.xhtm school?

  A motorist travels 160 km at 80 km/h and 160 km at 100 km/h. W(y u)o,c)xtgc hat is the average )(oct,yxg )c uspeed of the motorist for this trip?

  A motorist travels for 3.0 h at 80 km/h and / vpt;to.j0fu 2.0 h at 100 km/h. What is her average speed for thufp0 vj;.tot/ e trip?

  An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north fo6yotrsw, ( i(f1. wovlr 750 miles. What is the average speed ,vwstl6yiwo f.1o(r( for the trip?

  In a 400-m relay race the anchorman (the person who runs the last 100 m) forhx( mm4ff w1w0 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 ruhfx4 wmw 0f(1mnner starts the final leg of the race, in order that the team A runner not lose the race?

  A car decelerates uniform:s b h+u;eemsm83t33e f 8hkug3yqmy3y0x0dbly and comes to a stop after 12 s. The car's average velocity during deceleration was 56 km/h. What was the car's dece3b3qg3f8musyehyexk s +bm8 d0yt uh3me;: 30leration while slowing down?

  An airplane increases its speed from fvq06sdiijb,4f7d-b 100 m/s to 160 m/s, at the average rate of 7fb4sf-vqdb6 id,j 0i$15 \; m/s^2$. How much time does it take for the complete increase in speed?

  A car traveling 60 km/h accelerates at the rate of- za s71pylq*f $2.0 \; m/s^2$. How much time is required for the car to reach a speed of 90 km/h?

  A cart starts from rest and accelerr ijei;hl+2 zri9et /x zr-ikw: hr79,ates 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 wittt sfa iaq/8c766acgkw h2u +xb8 7t;rh a constant acceleration ak; wc 8i6f t+u gatq7xa2h7rsc/8t6 bof $2.0 \; m/s^2$ for 15 s. At the end of this time, what is its velocity?

  A cart with an initial velocity onode4b 2bj a +21yjx.df 5.9 m/s experiences a constant acceleration of do .1+d 2abbyx4j2nej$3.9 \; m/s^2$. What is the cart's displacement during the first 7.4 s of its motion?

  A bullet moving horizontally to9y;w/ngs5n-vkh+ w ax)-rkhm the right (+x direction) with a speed of 419 m/s strikes a sandbag and penetrates a distance of 21.69 cm. What is9-sk )n aghxky- n5/v ;whr+wm the average acceleration, in $m/s^2$, of the bullet?

  A jet fighter plane is launched from a catapult on an aircraft ca7*qy3l,g 6c ypeg6q t0spu(dirrier. It reaches a speed of 42 m/s at the end of the catapult, and this requires 2.0 s. Assuming the acceleration is constant* 7g qlpi(d0gcypq3 6te ,yus6, what is the length of the catapult?

  A car starting from rest moves wi0 srz;xzk2gl:mmet ( 9th 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 m0imbr wfyi d, q1 gj8jv4z,5j-/s in a distance of 200 m. What is its average accelerat j, m45wj8b z0y-qd1vr ,gjiifion?

  An object starts from rest and undergoes uniform accelerato . , -/gwkj2hwm0vhrm/vr:kgdi p8: zion. During the first second it travels 5.5 m. How far will it travel during the thirdgrdw 0j/8z kw. /- mri:vhg2mhk p,:ov second?

  An object is moving in a straight line with constant acceleration. I42rxj mvi8od;2l -swlck1f1 a nitially it is traveling at 16 m/s. Three seconds later it is traveling at 10 m/s. How 2 1vs1cj8l4iwm-f;a lorxkd2far does it move during this time?

  A car starts from rest and k3;8w c/mcke zaccelerates 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 dwumo 96(v xd4lbs :1ljf7dne5 ecelerate 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 hv8nd 3m, r y.cs0ve2thas been waiting at the intersection starts ahead with a m28dv.3ce0tr vhy ns, 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 12 m/s on the surface of plhn// ,i.qt(dt rtyt 6zvvo+:k anet X where the acceleration/tro ,.+6 y (:tnivdkv tzqht/ due to gravity is $1.5 \; m/s^2$. What is the maximum height reached by the object?

  An object is thrown upwajv.ev5:swosmb -; q 9ard with a speed of 12 m/s on the surface of planet X where v -v:.es5w 9mbjsq;a othe 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 hjp*6 zc/x o(sec2gb7the surface of planet X where the as7e x(c6cb z*ojp/h2gcceleration 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 x jak;:t6rm9+ 0pxftrksgn2 * a speed of 14 m/s on the surface of planet X where the accelerationtag2 mf:t6nk j*r+xx0;spr 9k 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 sx0;l vi(tik zf1+ fip0. If your friend holds a ruler between your fingers and releases it without warning, how far can you expect the ruler to fall befor;i(fx01fii l+0 ptvzk e you catch it?

  A ball is thrown upward at a velocity of 3ng ;m5elrj /y19.6 m/s. What is its velocity after 3./5m y;gn l3ejr00 s?

  A bullet shot straight up09k- ;ddblc bw returns to its starting point in 13 s. What is the initial speed of tbl d;cb0d k9w-he bullet?

  A ball is thrown straight up with a speed of 36.0 m/s. How lon* xp zw5i 7xk2m4qlgf-g does it take to return to its stz x*5xq g-i74mfwkp2larting point?

  A ball is thrown downward from the top o0 +du(g)sc- yfqt- )arqf3mu/r o ix7xf a building with an initial speed of 17 m/s. It strikes the cm0+tofr3si-fq x (rudga /y)q)xu7- ground after 5.4 s. How high is the building?

  A ball is thrown straight up with a speed of 30 m/s. (only fi4:/dmega i lh)+qpfs +,jv.mjll in numerical value in the m.+e :+h a,fd/ijlq p 4)msvgjblanks)
(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 ofx5n 2*2egsnfd 25.4 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 velocity at t = 1.r.pcx+2 0e3yh . ccbz)5 rwtr*kk5ev/tsn2tk 0 s?

  In Fig. below, what is the bw8.f l5+luk e*eg v,yp9vvh f,uu/- ovelocity at t = 2.5 s?

  In Fig. below, what is the velocitqk s 93exns0fji9(-8v yp r7auy at t = 4.0 s?

  In Fig. below, what is the velocity a p;uroabf56 9bt(trv;t t = 5.5 s?

  In Fig. below, what is the a2q78,k/mxvauxevx f 4 verage velocity from 0 to 4.0 s?

  In Fig. below, what is the averag r-jxslt8 dt*ac*8u2ce velocity from 0 to 6.0 s?

  In Fig. below, what is the accelera2/+9eqltie,ts /xvh64 yq n fstion at 1.0 s?

  In Fig. below, what is the accelerathwiaf.+v 3 qcph*84vp ct6pp5b0r 0vfion at 3.0 s?

  In Fig. below, what is the average acno)t,mv;5gkzrh 6zz cm38b7wceleration from 0 to 5.0 s?

  In Fig. below, what is the avkxbrt1q 43 nj*erage acceleration from 0 to 8.0 s?

  In Fig. below, what is the di3e mrkq z- e;yfgx,wj3vn./7o 0smc (esplacement from 0 to 8.0 s?

Does a car speedometer measure speed, veloc e/m l(7.cc)lbyd r6l1 rnrhh)ity? {speed|velocity}

  An object can have a varying speef5cxyw b b8i2*d if its velocity is constant.

  The velocity of an object can be negative wha.tnwk+:x/mgn ) hslh: (28bpvjuw* ken its acceleration is positive.

  If one object has a greaa m at:.9d-w9daqb . jq-wnyp0pu8up/ter speed than a second object, the first must have a greater acceluj8ya0paup-qa/bd : -w9..m qp9dt wneration.

  Two cars emerge side by side from a tdiv+ pzkwl-7 q rnbo-h(e-o),unnel. 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 speed as its acceleration de.fkol 7.iyzrjo f qdpd) r u1e8f-c8;-creases.

  A baseball player hits a foul ball straigd4wd61d av7 ziht up into the air. It leaves the bat withv7 az1d6i w4dd 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 object speeds up, what is happeninqi0a fm, f2b-ng to its acceleration, how does it change if air fri,qb in2-f fam0ction is ignored?

  As a freely falling object s,hz)on p-bcyq w 3o5w/peeds up, what is happening to its acceleration, how does it change if airw 53byw cp -o,zoq)/nh friction CAN NOT be ignored?

  An object that is thrown vertically upwa ldf-m0c3d 88.7jdfj1 d msyshrd will return to its original position with the same speed as it had initially if air resistance is negligible. If air resistance j8f -c 3mshs8.ld1dy fd0jdm7is appreciable, how will this result be altered?

  An object can have zero velocity and nonzero accelera6w.vdv,3(o4 ah rjifstion at the same time.

  An object can have nonzero velocity fvl1jze36 fb ygw+16eand zero acceleration at the same time.

  An elevator moving from the second floor to the u jbv,fhsbyhro/ 2a oqsx-/,x8)nn ,6 qxkl.;fifth floor making no stops alonsorx;abvx,/f kqj 6,x,-n l/ hsoq8)2.yhu nbg the way has zero acceleration all the time.

  A rolling ball moves frog phq jlt4s(w;zfv -7-m $x_1=1.9 \mathrm{~cm}$ to $x_2=-4.5 \mathrm{~cm}$ during the time from $t_1=1.6 \mathrm{~s}$ 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 $t_1=-4.9 \mathrm{~s}$ is at $x_1=2.3 \mathrm{~cm}$ and at $t_2=3.4 \mathrm{~s}$ is at $x_2=8.4 \mathrm{~cm}$. What is its average velocity?  (数值)  $cm/s$

  A person jogs eight complete 1qq +kougy8and6srb.b+/ + gelaps around a quarter-mile ($1 \; mile = 1609 \; m$) track in a total time of 12.3 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 97k9jc h+ p-co+v m away in 12.3 s. It then turns abruptly and gallops halfway back in 4.6 s.cvh9c+kjp+o - 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 wgm9j;x uh (r3$11 \; m/s$ to $24 \; m/s$ in 5.3 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 lvn48jf)ph1 vo;sku ( $16 \; m/s$ to rest in a distance of 81 m. What was its acceleration, assumed constant?  (数值)  $m/s^2$

  A light plane must reach a speedft+yrp5u 4csdo we4 +7 of $30 \; m/s$ 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 abuhg:v ti8u u(e8:ru9oc9lp6p out hu :tl8prue8(uvp: c99oiug6 $10.9 \; m/s$ in the first 11.0 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 uni,lm sgs+8-ir iformly from a speed of $19 \; m/s$ to rest in 4.19 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 th5tniy vis1 hco9kz+2 )e highway. Assuming a decs2z5vh+ )ti 9iyk1n oceleration of $7.00 \; m/s^2$, estimate the speed of the car just before braking.    $m/s$

  A car is behind a trucks/d(wa5pzdd1:pryt ow-1nh : 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).    $m$