Which of Newton's laws best explains why motorists should l*t8bpv4+ile(*n;le . glhpu buckle-up?

  When you sit on a chair, the resu 2q4s 48br uegt5+o9gto ;eonwltant force on you is

  In the absence of an external force, a movinga8ozs qgby f 5 qce*sn**v+(;p object will

  When the rocket engines hki yt+ zi+(ljj(/ss,on the starship NO-PAIN-NO-GAIN are suddenly turned off, while trakit,lij (h+(s ys j+z/veling in empty space, the starship will

  A rocket moves through empty space in a straight linel2ys qrixr/,1u y.n fh;vget)20 x) ly with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to rrs;u y n)yy ghe f0xiq,.221v/ll) xtthe rocket in order to sustain its motion is

  You are standing in a moving bus, facing forwarp+8;yu tivrb; d, and you suddenly fall forward. You vb8 r+p;i;u ytcan imply from this that the bus's

  You are standing in a moving bus, facing fordv5nl3 ;2rip dward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused y2nl;v d idrp53ou to fall forward?

  A constant net force acts on an object. Describe the motion of tw5, 7nlq/ cb(f- au.rxdhouq/he object.

  The acceleration of an object is inverst3fni(b1a4 b*xhkdj 2ely proportional to

  A net force F accelerates a mass nuiyd 1i8;y0gbo s0c33bsp; nm with an acceleration a. If the same net force is applied to mass 2m, g;3 18isd nnsycboi0p30;ub ythen the acceleration will be

  A net force F acts on a mass m and produces k dbw97a,; ckhid qt jzh/w;9 6t*pw+ban acceleration a. What acceleration results if a net force 2F ac+ 6*hw7/tbddzw,tkhbia 9 j;qp9k ; wcts on mass 4m?

  If you blow up a balloom9:/0d (m/bgx )gtnx6qlot enbf-,r un, and then release it, the balloon will fly away. This is an illustration ofn (bndg -ltf/rqxx :t0gem6o ) u,/m9b

  Two cars collide head-on. At every moment dur(m67k+1xr3 uzifgvg5 idn,r jing the collision, the magnitude of the forcr vx71(id+ ki5g u6r, 3njzfmge the first car exerts on the second is exactly equal to the magnitude of the force the second car exerts on the first. This is an example of

  If you exert a force F on gy2. hbshr2h 7an object, the force which the object exerts on you wig2.hsh r72ybh ll

  Action-reaction forceyv+ thm :f35xas

  Action-reaction force/zy./y x o+j6boi zid8s are

  A 20-ton truck collides wi*g6qrlaza 83.8 etnzxth a 1500-lb car and causes a lot of damage to the car. Sa63qlx . *z ntr88gzaeince a lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pc o1w:8f: h bt/0)kzbwehjc u2ulls on this object with force mg, which we h: bfb)z02:e8w1wotk ccjh /u will call the action force. What is the reaction force?

  A child's toy is sus/*iemhpm9bbrr/97s0iydnjs;n y3 l 6pended from the ceiling by means of a string. The Earth pulls dowprbid6/syynei r nh 3s*mb9lm/j7 09;nward 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 +qqx (i*xf tkry::zw,with a 1500-N instantaneous force. The ball hits the bat with an ik*w( :rxq+z:fqti,yx nstantaneous force, whose magnitude is

State Newton's three lawckm12afdd2nb(m + d 2cs.

  Mass and weight

  The acceleration due to ,p82q (ypu obff (itl+q1-csegravity is lower on the Moon than on Earth. Which of the following is true aboutoiyc,8(pf f2pql qs e(-+b1 ut the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which x0nzti+gtm+: acts at a distance is

  Who has a greater weight to mass rar)cc,qo,x117 duqy i1 6aci/ ,kvtwyatio, a person weighing 400 N or a person weighing u, trwyk)v1q1o6/,a,1c7dcxc iiy a q600 N?

  A stone is thrown straight up. At the top of its path, the gkypsmh2bo/ :3sl6 gnf/j;s; net force acting on it isfj;o/bsnk y6:l2mssh/ p;3 gg

  A 20-N weight and a 5.0-N weh-e5nh yw9z8p ight are dropped simultaneously from the same height. Ignore air resistance. Compare their accelerationz hpe5ny98h-w s.

  A brick and a feather fall to the earth at their riw9wyb 2ux0 (li9 y6quespective terminal velocities. (wy29w9x i6uulyq ib0 Which object experiences the greater force of air friction?

  An object of mass m is hanngpuwv10tmjz +to+ov ,/b*8m6v*hhm ging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What+z* /*w0t6m ,v1b hmovuhm8o +t vngjp is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevatqp +-c ,arto af16z/- qq 2h:zjcu4subor. The elevator is moving upward, but slowing down. What is the tef 2h-p: 4c uq,or z 1/z6+uja-tasqcqbnsion in the string?

  The force that keeps you from sliding on an icy si4 dul8 l 6j;upq1w5.pg0bchyddewalk is

  It's more difficult to start moving a heab+f w5x4 ,:3 .xpuupp7*azk0;wmewt h na7caivy carton from rest than it is to keep pushing it 7nafk;pa3xe7p *ih puz x0 +:u4mw bw. wac,t5with constant velocity, because

  A horizontal force accelerate3 vyti8+1m fyzw.+glleo-8 zk dj8 wy/s a box from rest across a horizontal surface (frict l1.gk z3w8 m/-yewtyodzy+i+j8lf8v ion 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 happens to the box's acceleration?

  A packing crate slides down ant rfw1 p3aks:+ inclined ramp at constant velocity. Thus we can deducs:k a 1t3wpf+re that

  A block of mass M sl ,(fk 4uba ko2fj6v(bgides down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exert , kb(oauk6 24gfjvf(bed by the plane on the block is

  A block of mass M slides down a frictionleulh2nl8*m ;a ph)bcfo2 y/fn.ss plane inclined at an angle q with the horizontal. The normal reaction fou2hnm/b pf*l lfc2 h ;8a.n)yorce exerted by the plane on the block is directed

  A block of mass M slides down a frict lpv17f3d+mcuionless plane inclined at an angle q with the horizontal. The gravitational force+fc u mp7l13vd is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an in/z3ck7jyccl -clined plane that makes an angle of 30e with the horizontal. c-cj7kyzl/ 3c Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless su /cno:u o)g9curface. A 16-N force is applied to the object, and it9ouou :ngcc/ ) accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1 hv1zbwe9;k t um,8wk0000 kg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward force on the cark1zbwhw 08m;,vkeu9 t?

  Starting from rest, 8k1d w+nck+ kta 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on the 8 nd++1wkktkcbody?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of x5 zwy93)dwfv 50.0 m/s after travev x)wfwzd3y59 ling
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 a 10-kg mass from . eo bw lb,q3xuc o6u(;;iere(rest,x r;eb qeu;(,.3ewo6uboi lc(

  What is the mass of a person who we3po9nf0 8 nr*uf;jv5ixffldmq:j9 s +t2pu f5 ighs 110 lb?

  What is the mass of *dz4t onz/9w(ea8n+n o s*x nfan object that weighs 250 N on the surface of the Earth where the acceleration due /xzodst *nnwne+o( *n 9fa84 zto gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Ea.8v; aloj(o qwrth. What is the mass of the object on the surface of the Mqaolv;w (8o.j oon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object;0v+2l /igok p/uqv px.t3 mmv B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Cxmim0g/;lu+qpvov /t2 . v pk3ompare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a g ;/ ni 8b1 unx n)m*8rhvj3xmi,a.ayf5.0-kg rope. Sue pulls with a 15-N vh.nrni8 b/,yajguf* xx8i;nm13 ma ) 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 force Fnekp suv73to w3 exn6 7(j;,hs acts on the stack, and it accelerate ;xss7k3t we3(,o7hnjvnupe6s 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. What will the sca3h zz0a6sp k/xu)pkc(le be reading when the elevator is aaxz(k 6up 3h/zk s0p)cccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.0 kgeq q/iixnp my 5j046q; and t/n ipiqy5 qx;j4meq60he elevator accelerates 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 the person is 60.lu0x8,j tghk.0 kg and the elevator accelerates upward with al jhk8u 0.tgx,n acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on 3mra*z6nbpb lzlb*c.xrm3nf- 0 u11la 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 6.0u6*lzl *xmn pzb 1r mf- 1.3cnbr3la0b N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatrt,i 3 ecvs+h.bed of a truck. It is held 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 slid, rstev3hc .i+e forward into the cab?

  An object of mass 6000 kg rests on fv-r )pu f+d3mk c3/hithe flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m r3km3i/-ff+uvh)d c p/s, what is the minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shok ucp bsn)*7 p.o ,t9)qolklr:wn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignor.:*lq),k t)nrok bu9c op7s lpe friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0tideivu0 34 u:.40 kg, what is the tension in the string? (Ignore friction and the mass of the puev30i :udi 4utlley.)

  A student pulls a box of books on a smooth horizontal floor witdy gf4 ybwc )h/-,4npth a force of 100 N in a4d h/n fwtb-gc4yp, y) direction of $37^{\circ}$ 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 wpx h2,b7e apvqa;)2 mnitjxh* r-u 4e9ith a force of 100 N in a direction of 37.0e above the horizontal. If the mass of tbmh)u eq;jx-taae9i v 72pr4*, hxp 2nhe box and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is su +,uj- jdhqy3upported by two ropes as shown in Fig. 4-2. What h yd+uq jj3,u-are the tensions in the ropes?

  In Fig. 4-2, if the tensions )lwi 7*kqpqo a:yw)n)in the ropes are 50 N, what is the mass of the traffic lig )q7y)kp*iwn wal o)q:ht?

  Two boxes of masses m and 2m are in contact with each ot+5tki8im /ojb j)efhf. 3b-euamts)j.*us b 4 her on a frictionless surface.s+ueu bf i*jeb8/s5boa ft3.4k itj.)m m-j)h (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m 4zl8zn;ni5x/r3qi hmare in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more massiv /qnnh;lz84 z53iri xme box?

  Two boxes of masses m and 2m are con8fgu,xfu ai *7+t3/8 cgfuqthnected by a rope. (See Fig. 4-4.) If the forward force on the mor8 f/au*f hu+c7ui,t8g xtqgf3e massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m t)q bw*yzb;2usw wg1-and 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration 2sw )wbyg;1*tbqw-u zof the less massive box?

Two boxes are connected by a cord running over a pulley as1-/m6ol8gl fllui-si(ko.hl shown in Fig. 4-5. Box I of s ll1g 6hi/ -o(8ukm-f ll.iolmass
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 fri + 7y/:(k ,izo9rmqcmo 9k;p/i n8lvhoo vj3pkctions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applik/jmk/9o 9phko3n 8im i,7oqp:oy+; v(lzcvred to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50 fxo; h4rvnv 7qatr. db*n/r*( and 0.v *n/*oft4r.aq xh;(vrdb7n r40,
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 direction. xj9zev-hy- tr+8g rw3It slows and comes to a stop wi8+ e-r9xwvzjgy 3 -htrth a constant acceleration 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 eew 44dm(;+n .twexq++ jmnpf horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of the object?wdpq++fxm .tew+n(e n;e j44 m

  A horizontal force of 5.0 N accelerates a 4.0-kg ma-tsiwb6q h /c me 2uxk.64dxv2-y;jsgss, 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 puck is given an ini vlz cuo8zg 9yb.-nq8 aeo)// tan1ud)ji,vu- tial speed of 10 m/s. It slides 50 m on the iqive).,u u/vacbyunl zj8g 8ndoz t/19-a -) oce before it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid 6p* c6hk ts4a ;z ctwz,:opc)0 kwbyg-marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.564z- h)p 6kgpw;z0ctac,cb * stkw o:y00 for the prevailing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked.uwp;*.kh ol)q7qbg (z (See Fig. 4-6.) The surface between the more massi*w(l.zghbqu )7op ; kqve 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 3m are stacked. (See Fig. 4-6.) The surface1v8xtr dhdk-; between the more massive box and the horizontal surface is smooth and t -hd8tkx;r1 dvhe 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 friction between the boxes?

  An object is on a frictisw ay1-s7 vkg0fjq(l6 onless inclined plane. The plane is inclined at an angle oflvq (- 1asyj7w0skf6g $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flai73xux ;lvoe, t hill that makes 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 inclined plane with an angle of -ra;et*fe+z.o vtu0n$37^{\circ}$ 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 smooth inclined plane tilted at an anx(je xkv7lk 6kf +kl3)gle 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 down an inclined plane, at a constant velocity+mjuamn,) 23 lhx,v gx of 6.0 m,gj)ax2 m3+,ul hnvxm/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 a rouux8t, 34z khcs//s(v uolloh8gh $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m/zwr 0g8zvso8se;a lbc *rh-3 slides 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 x h:ik f8dsf+b*s5+rsto ;tfu-uq3d9N along a rough surface. The cable attached to the log makdu: thsfxb-dfi3kr;t9s5ouf*8 +s q+ es 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 rou,n2; ;3tf qzvr yupak4gh inclined plane tilted at an angle of ;k rpay3;2fz n ,qvut4$33.5^{\circ}$ 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 incline is graduallykm: 4((nxeqmd ) f18ilzfh cm4 kv1tt9 increased until the object begins to slide. The angle at whiif tmx9 eq(c1mzh8)4 vl(n :tkdk1 f4mch this occurs is q. What is the coefficient of static friction between the object and the plane?