Which of Newton's lawsb0jlf/ o)3 )( cg(e 2cypxl kzrzwa3u: best explains why motorists should buckle-up?

  When you sit on a chsm)j44e0. k sznf:4db jzbc6uair, the resultant force on you is

  In the absence of an external force,:w ik,n+0zl rbb+o7ofav; . cm ombm:1 a moving object will

  When the rocket engines oiqc-/l8rk //ct :t+a7fve wy un the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starsh+a t/fec iw tyrc87l uk/:qv-/ip will

  A rocket moves through empty space in a s4gzx,fjqxjtml2 k9o+ p 5*+2 t4hzn mmtraight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the f+f24t9lz pmxg+5 qz2kj nm, jt*hmo x4orce that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forwarojxslz)u v-n/(sz3 +nd, and you suddenly fall forward. You cnz/u z+nsv)sj xl 3(-oan imply from this that the bus's

  You are standing in a moving bus, facing f 0npdulq5 zl0vj /p14p1x ca.uorward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused 4capx l/0p.01 vjdl 5pq1zuun you to fall forward?

  A constant net force acts on an objec9 wa4c )l:xgmixdgo9oi +-e3gf1 i:m st. Describe the motion of the object.

  The acceleration of an :hmyjdoun85g1gh r 2y w8.q :jq)3vc tobject is inversely proportional to

  A net force F accelerates a mass m with anq/e 30qounhxj*q-/ yk ag.m-.1:q p qerr+arb acceleration a. If the same net force is applied to mass 2m, then the accergn. r3/ ou*/:qakq-j1qy+.pxq ba q - h0mereleration will be

  A net force F acts on a mass m and produces an acceleran r12 zx;f(hd:ouxz b0tion a. What acceleration results if ; od f2xu(n:zx0rz1 bha net force 2F acts on mass 4m?

  If you blow up a balloon, and oti0l koi .c, )2+qvipthen release it, the balloon will fly away. This is an illustrati oi vkit+o2.pc)0,qil on of

  Two cars collide head-on. At eve0o*qvjas3 amt-fa5/ ary 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 exert m/j3s *a to5qaa-0afvs on the first. This is an example of

  If you exert a force F on an object, the vegbt:c ,we,nr*yi:. x r7yj9 force which the object exerts on you wix ytbyw9cein. j ,v e:,*r7:grll

  Action-reaction forc7j gvc8- 6imkoes

  Action-reaction forces arm771l bok6qifx se6c2 e

  A 20-ton truck collides8.:yq/lwj ix 0k,kba md*cka, with a 1500-lb car and causes a lot of damage to the car. Since a lot of damakqc m*ak dy x /wia.,jbk,:08lge is done on the car

  An object of mass m sits on+cg+xj 4n,d vo a flat table. The Earth pulls on this object with force mg, which we will call the action force. What is the reaction forc+dxc4g+v,j n oe?

  A child's toy is suspended from the ceiling by means of a stri ,ap-jjanoi.7ng. The Earth pulls downwij7ponj a-.a ,ard on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. The 1q (h03k(epzdku +luzv. k nt5ball hits the bat with an instantd1( k (lp.zk u+htuqze30k 5vnaneous force, whose magnitude is

State Newton's three lv,*3np ,4 pcs,o1*.wb;kvl xbqgna mhaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Ear+/u71:xidil tswcf q0th. Which of the following is true abou7f:xlqitu +0/ws 1dcit the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at t8nurfx - rfc0)5:.8jop2g)rsyccoka distance is

  Who has a greater weight too4sdq0dds,rb5(s e 1y* k6 xki mass ratio, a person weighing 400 N or a person weighing 600 Nk ey54id1sd(b srokq60d*,sx ?

  A stone is thrown straight up. At the top of its path, the net force :d85r aopj/wj acting on 8pw: rjdo5j /ait is

  A 20-N weight and a 5.0-N weight are w:nj ag2gl h35dropped simultaneously from the same height. Ignorwanl:g3g 2j5he air resistance. Compare their accelerations.

  A brick and a feather fall to the earc: vq5uek4z: mth at their respective terminal velocities. Which objectz:ke u:c 5m4vq experiences the greater force of air friction?

  An object of mass m is hanging by a string from+ux6xu;x;t ;yl jdc,l the ceiling of an elevator. The elevator is moving up at constant speed. What is the tension ix d+ 6,uxllcuty;x; ;jn the string?

  An object of mass m is hanging by a yl1wvd .4yp ;bstring from the ceiling of an elevator. The elevator is moving upward, but slowing down. What isl b. ;vwypy4d1 the tension in the string?

  The force that keeps you from sliding on an icy siy: hpsnslb(be5 26 w1mdewalk is

  It's more difficult to starr) )pxqi*9 fzst moving a heavy carton from rest than it is to keep pushing its xp*)fi9qrz ) with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal su eg. x1j z*0xhbccoam,8rt(;brface (friction is present) at a constant rate. The exper*j1max8zr 0( c;bhbg , teocx.iment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramk-n(b3gyjr.wd. d zf9 p at constant velocity. Thus we can deduce thnjb(dyw9z-g r.3.fkdat

  A block of mass M slides do.:dn)m 2u0xgb 9goc2amu h+fawn a frictionless plane inclined at an angle q with the :g2 b)odg cm nmh2x09a.fuau+horizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slf:jgk-* sax:hides down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by -skg:hfja *x:the plane on the block is directed

  A block of mass M slides down a frictionlesshwdi9 8/at-xkobtqc42 y w+w0ip b7m( plane inclined at an angle q with the horizont-q b+oc4y0wd h wa/9 txkbt(2w8 p7imial. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on(pjgdn3ku2ql;jy o/l o )u3f; an inclined plane that makes an angle of 30e with the horizontal. Make a statem3;2lj3 yu o(;jk /lugnp)dfoq ent which best describes their acceleration after being released.

  An object sits on a frictionless surface.pw0c0/ail8 / x ysir(v A 16-N force is applied to the object, a00sar 8wvxc /i/lp yi(nd it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acceky6m06 rpty 6hv9vu9 yy -vl9ilerate from rest to 27 m/s in 7.0 s. What is the averag9 6vvl y r0yyvyt-9hk69up6im e forward force on the car?

  Starting from rest, a 4.0-kg body reaches a u+qv mlhmx(2 97 z)yvuspeed of 8.0 m/s in 2.0 s. What is the net force acting on the body yu9vvl xzm)qh +7m2u(?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 )69ug:bm-u(so ntnw/mjce0m m/s after trav6nw )b-etj: u om(umc/n0g9s meling
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 ys,m,y 3 dhq zx -d34utvouc32gou push a 10-kg mass from rest,u,d x uo2qd4g, h3zt3cs -3mvy

  What is the mass of a person wd1dzgk0s1.fspd)ib 6 9;x okhho weighs 110 lb?

  What is the mass of an object p r9drfs:(zz/ that weighs 250 N on the surface of the Earth where the acceleration due to gravit9:/( dzrfzr psy is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is ty2-q p78zxint he mass of the object on the surface of the Moon wq-2 p tz7in8xyhere the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, ag*2d *t(q kajxx4ewf3 u/)izq nd object B weighs 40 N on the Moon. The Moon's gravity is ojqz e2/xdf*(* 34qgxua ti)wkne sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are havincp)z asr-1mp6 g a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N )1-6amp rzpscforce. 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 force F acts on tcx7vp o 9wzo/ etr1;1the stactv zx;ort9 w/p1e17o ck, and it accelerates at $3.0 \; m/s^2$. 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 on a scale in an elevator,ml21*8c rc 4mmy oalv. What will the scale be reading when the elevator is accelerating downwa *a1,8yvcl rlm4cmo2mrd at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mafe iou31d6nk0yj8ee7 4d1 vstss of the person is 60.0 kg and the elevator acceleratdv37o yj6i0euk4e f1tsn 8e 1des downward 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 vc5* ardrm2z9 the person is 60.0 kg and the elevator accelerates upward with an accele d92rczmvra5*ration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces kfc4 .popawt+ h/c14oact on a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the accelerat/kp ha4ct f poc.wo41+ion of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is heldo0 y2we-+g8gz v2 zcw7ud4wxv in place by metal brackets that can exert a 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 w7z8w2d 2uog 4-+yxev0cwzvg into the cab?

  An object of mass 6000 kg rests of3fhdjk e0+ o) ,luzr.rg(ku(n the flatbed of a truck. It is held in place by metal brackets that can exert a maximumfu3k j)(d+(fr0uhe.l kzr go, horizontal force of 9000 N. When 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, if M = 0.60 kg andeh yx;to ptu1 hx5/1-s m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of the p;1yhxh5xt us1tpeo/ -ulley.)

  In the Atwood machine shown in Fig. ; yi+ s7db(cdu4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction ay (d; 7b+dcuisnd the mass of the pulley.)

  A student pulls a box of books on a smooth horizontg k51dz: lqc1jal floor with a force of 100 N in a direction of lqc dkj51z g:1$37^{\circ}$ 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 horili e4wkd 4nt2*uibv92 zontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.0 924w knvueidt2i l4b*kg, what is the normal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown in Fig. zpla(,l tclr 6*s(qkj2-m-ch4-2. What are the tensions iz,qc sajc-l l lt(-m2h(kp6*r n the ropes?

  In Fig. 4-2, if the zm-zc*+ict4 1 7cj9htpx 3)qnw-ybbdtensions in the ropes are 50 N, what is the mass of the traffic mwhb-91-c+dcq ytbjx pnt* z4c7iz3)light?

  Two boxes of masses m and 2m are in contact with each other on a frictionlesscqop07 yw4gj. surface. (See Fig. 4-3.) What is the acceleration of the 4gq. o7 cjypw0more massive box?

  Two boxes of masses m and 2m are in contact jx*nel:6z :qy with each other on a frictionless surface. (See Fqy*xen j :6:zlig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If th2pfd3 blfa, f.ues:*we forward force on the more massive box is F, what is the tension in the connecting rolae :fuf3.wdpf ,*b2spe?

  Two boxes of masses m and 2m are connected by a rope. dfzipv69f; 4x2 iu r8r(See Fig. 4-4.) If the forward force on the more massive box is F, what irvifx62p8zd4r;f u9i s the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley akckb kz(rsn- 42,ep.g s shown in Fig. 4-5. Bosz4kk(c gk.e2br -n p,x I of mass
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 bowp9g0qym5 7jaw; otk7 x and a desk are 0.40 and 0.30, respectively. What9awpokyw5m70 tqg ;j7 is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of sttaf: zv9 hlyk s(o(7 e;ibl8qw:ddy3-atic and kinetic frictions for plastic on wood are 0.50 and 0 :l;(fdd-o8i z3y s(v9hw7lkbteya: q.40,
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 di : u0vsmi2uy o 9/zawe6b7*uanrection. It slows and comes to a stop with a constant acbo6navze mu9*au0 /wyu27s: iceleration of -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surface is pulled by a 5.0-N force. A 3.0-Nkhkr s8*j9fx;o-p4 hsg i9d5p friction force retards the motion. What is the acceleration of thed- ;r ho5k 4xf9 hgssj*k8p9ip object?

  A horizontal force of 5.qra-(q6hi g4m0 N accelerates a 4.0-kg mass, from rest, at a rate of $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a puck4 ew-1ruxpf b* is given an initial speed of 10 m/s. It slides 50 m on the ice efu 1xp-4 *wbrbefore it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police a 7+m).sgmadwn c tg19find skid marks 90.0 m long. They determine the coefficient of friction ga7w+scntm1 .) a9gdmbetween 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 arymc7l x:td1r-6uc mq* e stacked. (See Fig. 4-6.) The surface between the momrt ydclc7:-xq* 1 6mure massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the 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 b +s eb*zl ;3c)ijoec: 11suzf3m are stacked. (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 the less massive box does not slide on the more massive box, what is the coefficient of static ebbil;jcfzec u s+ o1s13z:*)friction between the boxes?

  An object is on a frictionless inclined pl fdz n*,p*h3f q 3p*dfstzy)8aane. The plane is inclined at an angl ff pq)ddf*3an*z, 8t3zy s*hpe of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes(xrfcb h qa*0 v6eiz+; an angle 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 inclb8cw ) znliija /ab6fz 8bb;du-4)vr6ined 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 smoo3zw )d:nbge s-th 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 directly doz yj)dd)1j*7 xkk3j ggwn an inclined plane, at a constant velocity ofgd j31)j )kzdx7y *gjk 6.0 m/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 slides down ytp 3dym u37h/;k2dnk8y zif 5a 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 down kd fclx *02ib;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 a39*kxx x8pk i;qfrzq) rough surface. The cable attached to the log mx xfi83*qzprk; x9) kqakes an 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 on a rough inclined plane tilte4whetz76n vw(8+og fa; u(b trd at an angle of b 4;e(u rww v+(tzf867othan g$33.5^{\circ}$ 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. The angle of incl6;+7 su1-hrmsfmbs ng ine is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction betweenmn61 s+s;s7rfgbh m u- the object and the plane?