Which of Newton's laws best explains why motoriq ehhj+)p t9.msts should buckle-up?

  When you sit on a chair, the resultant forceva k:*0eid zl+jd b0wauz3--n on you is

  In the absence of an external force, a :3yt0kthv(nxv 8fc e6moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suy: m)g+ae*m vta e4t;dddenly turned off, while traveling in empty space, t 4m:*agde;av)met+y the starship will

  A rocket moves through h11uztwb;(fp2q9eryw8 rqsv15d m w 2empty space in a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must beues 21wdb21p9t(q m5zw; fhw1v8rrqy applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenly funct-te-4ezaoc89 v4 all forward. You can imply from this that the buse9o-etcta z4v8ncu 4- 's

  You are standing in a moving bus, ve5c2:ws2 jk)v* rkwyz dei3-facing forward, and you suddenly fall forward a*v:w)k iyer wvc 5-ez 2djks23s the bus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of tucsz/ --p l.hs /i6poxhe object.

  The acceleration of an object is inversely pr76q9i ;9ljd bosiv:lsoportional to

  A net force F accelerates a mass m with an acceleration a. If the same net forclli i3 ;k33f u)jtgms 2r+9n5 zlv8cede is ap);id+ k2g5 uz3fl833e cnjsvlrmi tl9plied to mass 2m, then the acceleration will be

  A net force F acts on a mass m 2,otpdb6 bvj)q*u ld 0and produces an acceleration a. What acceleration results if a net t,6*jdp)b v olqb20u dforce 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly a wt/pwyppr4n6v3o (u l2k+y3 tway. This is an illustravpn+o tyu33t4 prw p (2w6y/lktion of

  Two cars collide head-on.lv ;z9u 6. c,amrn *f+dm9ycojv0 nyll )9acu+ At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second car eyvfl)alcru *uvc+;o 09+ya9c9,d n n6zmlj.mxerts on the first. This is an example of

  If you exert a forcew*bxpsht*c3q( o 40ww F on an object, the force which the object exerts on you wi b*(hsq*towx w0 3wc4pll

  Action-reaction forcegvlk(;fk (d jfavr24 1s

  Action-reaction forc u:ji.*- ozl g/ffnx*ses are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damanmv jq;2eljm,5i7p*p ge to the car. Since a lot of damagl v n e;p,*j5j2m7qimpe is done on the car

  An object of mass m sits on a flat table. The Earth pulls on sx+pk-1j hg8( pc(v jethis object with force mg, whichsp kj1-p+cx8j(e gv(h we will call the action force. What is the reaction force?

  A child's toy is suspended2 -zy4tvja ew6 j/5qnrcoozi5e0x ;:e from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "rea4 xo ee cezi:j z o;5q0/-2rw6j5yavtnction force"?

  Your bat hits the ball o4gf( zat7xg. 0z+pw xpitched to you with a 1500-N instantaneous force. The ball hits the bat with an .oagf7 xzzp+(0g4x twinstantaneous force, whose magnitude is

State Newton's three lawspxadyn/s -rl/vw;sa e ;+5 5id.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earq3 5r mmznph7i2ip4* q+h5ltyth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Eamzpr p5 7q3+y5*4t qmhnhi2lirth?

  An example of a force which acts at a distam,3j z o3n66fmcp: huunce is

  Who has a greater weight to mass ratio, a person weighing 400 N or a per.avr(-f 4x(k wckmki 9son weighing 6004 mkiw(9f.(r c-k akvx N?

  A stone is thrown straight up. At the top 7a,4t eyf-x o84kir ieof its path, the net force acting on it is4 fky r-4i7oaei8xet ,

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same h7lb9s7 6tq 5 hkesu3js ylx**nic5bx -eight. Ignore a5x7nlj3cs*lk u- tiqy*b6b9x sh 75 esir resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velocs4e u)hsd/ knzs;19 klities. Which object experiences the greater force of air fricte9ld unksz h kss)4/;1ion?

  An object of mass m is-7 .a,dmhyn zu8( fz:ln hgkd- hanging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tension in the string?nzkyh7dn:f amgd h(l uz8. --,

  An object of mass m is hanging by a string from the ceiling of y( q/hmd5;oo lan elevator. The elevator is moving upward, but slowing down. What is /od( lh5oy;q mthe tension in the string?

  The force that keeps you from sliding on an icy sizc ),xl7 i0po 58avxihdewalk is

  It's more difficult to start moving a heavy carton from rest than f1pg+ er ymc1k(bc, znur(y) ku598ubit is to keep pushing it with constant vebu9gpu81y(nrc,b1 5(kmf)+ eku y czrlocity, because

  A horizontal force accelerates a box from restzq;s 5do s ,gqom25e/ay: 1/drwodn,z across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happe 5e;qao/1ogzy n sz5 r2oq,wdd:/ ,sdmns to the box's acceleration?

  A packing crate slides down an inclined2jppxskz 6+ectda 08: ramp at constant velocity. Thus we can deducec+6t8asj 2ppz:0 edkx that

  A block of mass M slides down a frictionless plane inclin;z 3wxls b 00n :f8m8ixu3sbbted at an angle q with the horizontal. The normal reaction force exerted byb383: 0bn8 wxl;s0um sib tzfx the plane on the block is

  A block of mass M slides down a frib,1dnz/r, kx rv++4pqsf)jx rctionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is directex,nrzx j,d) f1s/rv4k++b qrpd

  A block of mass M slides down a frictybrh wv,8s((*ngv:q kionless plane inclined at an angle q with the horizontal. The gravitational force is diwbs8hvy , *knq(gv( :rrected

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on aw,qd4 (aqq87j djpfmav:ko )slyy.l/j-c 4n4n inclined plane that makes an angle of 30e with the horizontal. Make a statement which best de7 l4qk .)lsn 4-a yq: ovj/j4jya,c(mqfd8d wpscribes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is appl s/pq54 pac;jm*,n o)rtpwmt2ied to the object, and it acceleratqpro ;ppn)a45mtsc m2*, /j wtes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 k cwa7odct 6d-;g can accelerate from rest to 27 m/s in 7.0 s. What is the average forco;t7 ad6-dc wward force on the car?

  Starting from rest, a 4.0-kg body .x w*hs4o fw/h hyx mi:e;p;/,ydvm:wreaches a speed of 8.0 m/s in 2.0 s. What is the net forhwmwo .yhm/pxfw4xyd :;/ ev: ,;sih*ce acting on the body?

  An antitank weapon fires a 3.x3i +jg-mjgr+ t,c3oji 0keq100-kg rocket which acquires a speed of 50.0 m/s after trave jx,jkc1rmg +o3g-i+q0 jtei3ling
90.0 cm down a launching tube. Assuming the rocket was accelerated uniformly, what is the average force acted on it?

  If you push a 4.0-kg mass with the same force that you push vo vf,*jj:4 pnm*d4uns0lcc d 4+s bd3a 10-kg mass from reos4c bv,u3m**dnjc4l d:v fd nsp 0+4jst,

  What is the mass of a person who weighs 110 lb4a-oz f1(xnt i xat.1b virw0+?

  What is the mass of an object that weigh(k0m,4ooha wk3 z0jcbs 250 N on the surface of the Earth where the acceleratio 00(ojbawc4,3khm kozn due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 k9ne rr;-6phib b n)1zx 2cue27 e3edmqg on the Earth. What is the mass of the object on the surface of the Moon where the acceleration d23buc n7);b291em dnhpere6e- zr iqxue to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighsct2da6 c hi6q)iv+v;ea0zl7a 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of t0 e 7; cviathaav26cdlzi)+6qhe objects.

  Sue and Sean are having a tug-of-war by pulling on opposite -wdiz5qwfw73:e6vux ends of a 5.0-kg rope. Sue pu-w3e 7u5 fxzw:dvi6qwlls with a 15-N force. What is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A forcexvt8s pfa3eu.yxz /l71zx 5v 8 F acts on the stack, and it accelerates atlexp/x1xty78 vu 8sva .3zzf5 $3.0 \; m/s^2$. A 1.0 kg book is then added to the stack. The same force is applied, and now the stack accelerates at $2.0 \; m/s^2$. What was the mass of the original stack?

  A person of weight 480 N stands za7 a)z,yt9qw on a scale in an elevator. What will the scale be reading when th)taqz,z9y 7wa e elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of thqy:+zwl y. v6me person is 60.0 kg and the elevator accelerates downward v.zly+yw:6mq with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If the mass of the person i p h6;j0lxtpmwqaln:;n 6n21ns 60.0 kg and the elevator accelerates upward with an acceleranhjn0l;6w :qnx na6 mt1p;2lption of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. One force has a magnc vlb4t6hnyh7y) gl ;9itude of 8.0 N and is directed due north. The second force toward the east has a magnitud9v h )n;y6 c7htgb4llye of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests frd4 i:4chddjs rqyx-1957ry on the flatbed of a truck. It is held in place by metal brackets that can exert a ysdhd yr x-d i1f5rq4jc7:9r4 maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, what is the minimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is hev/u p)vz- u3dbbra(7f ld in place by metal brackets that can exert a maximum horizontal force of 9000 N. W rv(fdubvbaz 3/up)7 -hen the truck is traveling 15 m/s, what is the minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1,bj ,f/ue/ raovrz 6-z5 if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the ac 6/j-,zuzvb/re orf 5aceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0xfy e4lspqk/-ld o9s)-lxvy;tc 4aok+w7 */ d .60 kg and m = 0.40 kg, what is the tension in the string? (Ignov; //xty7qowfyp-)ll exc +d9-kaks 4d 4o*slre friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force oh i;0;6alrmfsf 100 N in a direction of 0lrh;msaf ;6 i$37^{\circ}$ above the horizontal. If the mass of the box and the books is 40.0 kg, what is the acceleration of the box?

  A student pulls a box of books on a smooth horizontal floor with a force of 1gqe -,e*qfi5kldq 2 9g00 N in a direction of 37.0e above the horizontal. If thlfegg,e q*29-qdqk i5 e mass of the box and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N i pt58ljfk q)7ds supported by two ropes as shown in Fig. 4-2. What are the5 f87kp ldt)qj tensions in the ropes?

  In Fig. 4-2, if the tensions inynhvgyh/pl2-, 8 siep:,auo:i)5j hs the ropes are 50 N, what is the mass of the traff2hys,vn p5i/y: hs)gp,8 iuha-l jo e:ic light?

  Two boxes of masses m and 2m are in contact with each other on :di; wji4vxg 3)gtp.la frictionless surface. (See Fig. 4-3.) pg vw) gd:;.ijxi3t 4l What is the acceleration of the more massive box?

  Two boxes of masses m and 2m ugsxz izp19s* /10l nfare in contact with each other on a frictionless surface. (See Fig. 4-3.) What zgu1 z /xisspf*1 09nlis the net force on the more massive box?

  Two boxes of masses m and 2m are connected by an84l mh58:kr9 vlmmb(aqexh5 rope. (See Fig. 4-4.) If the forward force on the mom8 x:ql rkh b5m 9n(ae84hlm5vre massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 24yn5+k7yrb loln b x-7m are connected by a rope. (See Fig. 4-4.) If the forward force on the more +5oxb4y7kl bl nn7y -rmassive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over b gtz0228l 5t ib;mmo5/jwgxqa pulley as shown in Fig. 4-5. Box I of mam2zogji8t /m5 tw; lb2q xg0b5ss
8.0 kg rest on the top of the table; the coefficient of kinetic friction between box I and the table is 0.10. Box II has a mass of 15.0 kg.
(a) Draw the free-body diagrams for the two boxes, identifying all of the forces acting on each of the masses.
(b) Calculate the acceleration of the system.
(c) Calculate the tension in the cord.

  The coefficient of static and kinetic frictions between a 3.0-kg bip b:02jf zwl a(/*9 xfzdy b1o5bz7xcox and a desk are 0.40 and 0.30, respectively. What is the net force on fj0*(a 9ilxpz :cywx 2zfbo/571 dbbz the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions f7y8wo(eixqx1mo 5 dws/v4 )exor plastic on wood are 0.50 and 0.40 o/vode5wy)w1xie8 x4 (m7xqs,
respectively. How much horizontal force would you need to apply to a 3.0 N plastic calculator to start it moving from rest?

  An object slides on a level surface in the +x dir1xl / q:pntu*hection. It slows and comes to a stop with a constant acceleration ofx u qtl*:h1/np -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surface ydv/xjq xl/5r6mj z1. is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleratix/q/y.5 jj1m rdz v6lxon of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at sf;1c;lpjtf a41, zzqa rate of $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a pucki1 ow imp+0nb3 is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction3i im +0onbpw1 between the puck and the ice?

  During the investigation of a traffic accident, police find skid m8r6dwu.h;.z ,py6r k+ ch*/n 3 kbpi,tax biejarks 90.0 m long. They determine the coefficient of frictionz/drac pk;,+i ek8 ..h*nw x6bt yrhjpiub3 6, between the car's tires and the roadway to be 0.500 for the prevailing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betwew z m orn97z( b74b.bnl:fs8aaen the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the 8a4 mwz n.b9l:arb(f7n7szbo less massive box does not slide on the more massive box, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stac8v*qjn6 7c.:;6ln yha; dy lu.l4ag luj obun,ked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If t,y7gl8uua4lhnj nb l;qd*nv ;c yjl6u 6a:..ohe less massive box does not slide on the more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined at a1mw7j) llxk*nuiv u 7p(j9gn;n angle of un)ljj;k uxp(lniwg9vm 7 17*$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an ai(*/ bmrrzdj+ ngle of $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclik jrcuq.) zjw631k dv)ned plane with an angle of $37^{\circ}$ to the horizontal. If the inclined plane is 5.0-m long, how long does it take for the mass to reach the bottom of the inclined plane after it is released from rest?

A block lies on a smoot .44defn8a ebuh inclined plane tilted at an angle of $35^{\circ}$ to the horizontal.
(a) Draw the free-body diagram for the block.
(b) Determine the block's acceleration as it slides down the inclined plane.
(c) If the block started from rest 8.5 m up the incline from its base, determine the block's speed when it reaches the bottom of the incline.
(d) How long did it take the block to reach the bottom of the inclined plane?

  A wooden block slides directokgawp3 uuhq t*j2/x*w i,5i*ly down an inclined plane, at a constant velocity of 6.0 m,** a3tgx/kwho*wj5q ipiu2u/s.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a mass m 5p -0yr)z ydhtslides down a rough $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m slides vc degkv,flft/ ;:593aa huy,down a rough $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. If the plane is 10 m long and the mass starts from rest, what will be its speed at the bottom of the plane?

  A bulldozer drags a log weighing 500 N along a rough surfacehu)s rq in*53s. The cable attached to the log makes ansrusiqn )h35 * angle of $30.0^{\circ}$ with the ground. The coefficient of static friction between the log and the ground is 0.500. What minimum tension is required in the cable in order for the log to begin to move?

A 25.0-kg box is released from rest b krirhmfugr,p)c). yk9 93)kon a rough inclined plane tilted at an anglek crg.ipb3h 9k) ,mu9)y r)krf of $33.5^{\circ}$ to the horizontal. The coefficient of kinetic friction between the box and the inclined plane is 0.200.
(a) Draw the free-body diagram for the box.
(b) Determine the force of kinetic friction acting on the box.
(c) Determine the acceleration of the box as it slides down the inclined plane.

  An object is placed on an inclined plane. The7gc/ 4d ( +fgp y3tu3k:nybiyj angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the jc4tn7yi yfg+3 /d3:kbup y(gobject and the plane?