Which of Newton's laws best explains whobcajrgrpc8ip0-7j 74 7;mfw y motorists should buckle-up?

  When you sit on a chair, the re2 .bcqe-aai2c7o 6xmw sultant force on you is

  In the absence of an external fosz.(28e6 ay r cof)bvcrce, a moving object will

  When the rocket engines8fs5e ;ue30a zb+lefd on the starship NO-PAIN-NO-GAIN are suddenly turned off, while travelin d 3fu;flz85eeb+ea0 sg in empty space, the starship will

  A rocket moves through empty space in a straight line with constant sper26 t ek.bt0l9 yuq) xbjuz,6jed. It is far from x66j 9kbqu.)blj u2e z0 ty,trthe gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocket in order to sustain its motion is

  You are standing in t0fyjf u)73wasuy/l .mtp0*vuf2yt / a moving bus, facing forward, and you suddenly fall forward. You can imply from thi)/u 0s/y.wyuuf7j*f 3tpfl2 0 at mtvys that the bus's

  You are standing in a moving bus, facing kp9:tkpk;8z ziwr * 5efkd6r+ forward, and you suddenly fall forward as the bus comes to an immedp *w9+z8k:kk5 zp;6trdek friiate stop. What force caused you to fall forward?

  A constant net force acts on e bvwg1vc). e8 */ foz3vxtow*an object. Describe the motion of the object.

  The acceleration of an 41 ws ,;08cv.c5p)yor zub,v fxn 89hua dbxdlobject is inversely proportional to

  A net force F acceleratesoi 5)ucwxb z91ucj60 p a mass m with an acceleration a. If the same net force is applied to mass 2m, then the acceleration wp09o1 u )bzc5uicwxj6 ill be

  A net force F acts on a mass m anb (,) x rwwpb wi1;px abi6xefz7 i4p0*a:c3xad produces an acceleration a. What acceleration results if a net force 2F a6i,erbaipa: (wa1pbx xp)cx b4 7 x3; iwz0f*wcts on mass 4m?

  If you blow up a balloon, and then t yv5;e )tnu 2byohk6-gdtz (,release it, the balloon will fly away. This is an illustration d ytu(bt5zt gveok;6n y2-),hof

  Two cars collide head-on. At every moment during the collision, the magnit3ru s jb1lyfi(- vm+y)ude of the force the first car exerts on the second is exactly equal to the magnitudbfs) 1ly iuv(-j+ yrm3e of the force the second car exerts on the first. This is an example of

  If you exert a force F on an object, the force which the object exerts on x*xr k h(i r. cke)g(num(p(n:vy n7b;you willk)xke y:n;7h(x(u v. pnmir gc( r(n*b

  Action-reaction forcest:gu8e sy;tv4

  Action-reaction forc0tqd2 q w1gol+b(g4dmes are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the c8sle b.mtmtoru; ,86-2ytkv tar. Since a lot of damage is st ekrtuml 68-, b;ymv2 8.ttodone on the car

  An object of mass m sits a ka2k:yw-j*g: 1eowzon a flat table. The Earth pulls on this object with force mg, which we will cale w gk*-j2 kayaow:z:1l the action force. What is the reaction force?

  A child's toy is suspended from tqshg zp qv4e6w1 zuuz5 3w1s5.he 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 "r6ws543qg 1uvhq5p ez z uwsz.1eaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneoum3e )ya4r cf6 nox5y2os force. The ball hits the bat with an instantaneous force, whose magroy3xfy oc5n2a6m e)4 nitude is

State Newton's three layun li*w82:uzsx+5ln ws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon thavcq)2qo xfi44n on Earth. Which of the following is true abo i x4fv2oqc4q)ut the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distance/7 gbbq ga)h0s is

  Who has a greater we.bp3 q(3bppaxrb(/ y0s nuwd 6ight to mass ratio, a person weighing 400 N or a person weighd3r6 ./qbwxu(apyn(pbsb3 p 0ing 600 N?

  A stone is thrown straight u4eobl ,ub-dov1m e26a p. At the top of its path, the net force acting on it ie1vabo m,6 b o4duel2-s

  A 20-N weight and a 5.0-N weight are dropped simultaneously from thealy l4f*u;+ 1vfx :-6e2lx*pv b5x;pzs tzq me same height. Ignore air resistance. Compare their acce+2l:x54yzq xpsext*v1zuv-;l;* p flma bf 6elerations.

  A brick and a feather fall to the earth at theib2dh *(lk9hr6 e)its xhr;jz z(z6 j6vr respective terminal velocities. Which object experiences the gh(b9 6 )vz zlstzjh dki2r*jeh6;r6(xreater force of air friction?

  An object of mass m is hanging by a string from th od9isdh)je+;uz i)(nc , g2oce ceiling of an elevator. The elevator is moving up at constant speed. What is the tension in the stcdin o+jo )sie(c,9udh 2 g;)zring?

  An object of mass m is hanging by a string from the ceiling of an elevator. Tkda bqjd.ycclcj y9 9 7po1rr34h7l63he elevator is moving upward, but slowing down. What is the tensicb76drc.lj j1 c3kd9 oy437rahp9lq yon in the string?

  The force that keeps you from sliding on an s g3yo66ibu(x icy sidewalk is

  It's more difficult to start moving a heavy carton fr hnx hu+5/4qg-x gi1m+n 9b9/sz noaqxom rest than it is to keep pusqs4 n1aixqbxoxu z g9hn/9m-+h/+n5 g hing it with constant velocity, because

  A horizontal force accelerates a box from rest across a horpjghqh :22k9 z m,kf/kizontal 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 happens to the bohhz,/m:2pk29k jgkfq x's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus we can w a8oyv3y5j5)su)xscyw a2:k deduce tw2c k su:y85oxavy )3)jy was5hat

  A block of mass M slides down a frioxms x:*vca 0g-z4xl)ctionless plane inclined at an angle q with the horizontal. The normal reacvos4 m:ac x-gxx )z0*ltion force exerted by the plane on the block is

  A block of mass M slides down a fric4*j0jr (j jigy u2dqpoi930o. zue h*itionless plane inclined at an angle q with the horizontal. jii.0 40yu *rh u2o9*qjzjjgi d 3ope(The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q with tl vq3u/* eq s6 skx(u/0oajrgnq65ck,; .a vxahe horizontal. The gravitational force is directedguqx, a0k5q v /.sxs6e*arj(clao n /q63v;uk

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on k7 o/ r 9pq;aiqzne.wr4j9gr7 guw-9 san inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleqgnqzpjer/ r9ra4i7 9w ; w.79souk-g ration after being released.

  An object sits on a frictionless surface. A 16-N force iujq5fmhaa.m40-)ul z s applied to the object, and it acceleratesa54l .huaj)ufz -mqm 0 at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate zgd- 254h nj*6rhcj ;ofszf l2from rest to 27 m/s in 7.0 s. What is the averl4* h 6znz2j5hc ;rffj o-sdg2age forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed oyhymp cer,/.* x-y6q wf 8.0 m/s in 2.0 s. What is t.-xr, wmqec*yyy /6hp he net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket 3qi7tj 3q 47)plomot7uy(m8 y lfl6sqwhich acquires a speed of 50.0 m/s after tra 6 j733lfy7qioqttlom 7p)8s(mylq4uveling
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 -lb+tbi b0es :1k*mxp a 10-kg mass from rest,tmeb:p -sbk xli01+ *b

  What is the mass of a person whim tku( 0 6umjpmh30o-o weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surfacml8/ b)ej2a3r) gss8c8 nfnfve of the Earth where the acceleration s8s2m) 3glrj)a n v/e8cbffn 8due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the objep+e u5*tv2dc lct on the surface of the Moon where the acceleration due to gravity is only vlut+d5e2p c* 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on t*zb) n8nn3x z b1m2fpthe Moon. The Moon's gravity is one sixth of Earth's. Compare the masses o83n*xzmbn pf2)z btn1 f the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends z 6n(2:orutis of a 5.0-kg rope. Sue pulls with a 15-N force. Whato :u(itn2rz6 s 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.m ; )dz)sqte0pj ne5.z A force F acts on the stack, and it q;e ztn.e5 sd jp0))zmaccelerates 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 ejw sdhko+pr039e v4.scale in an elevator. What will the scale be reading when the elevator is accelerating dowsv eojph 3+rke4 0.9dwnward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. jgwfkdu 8e6 rj05v-x7 If the mass of the person is 60.0 kg and the elevator accelerates du 56 kjgev -r0dfw87xjownward 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 personenp1 hc/gna -/ is 60.0 kg and the elevator g nae-1pchn/ /accelerates upward with an acceleration 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 haqp5 td4 ao:s1c f514eina snk/s a magnitude of 8.0 N and is directed due nq4s a /415f opcistn1n:ekd a5orth. The second force toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a c jk3c*)kj/bptruck. 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/jj*c bc)kp 3k to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a tru*x49yjjo)r* kv i lc(uck. 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 timex yj)49r*i juvl(*koc 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 and m = 0.40 kmo6mqm4kr- 8 pg, what is the magnitude of the acceleration mp -o64qrmm k8of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m iws1uk -ct(0u= 0.40 kg, what is the tension in kst 1u-ci( 0wuthe string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with./ l1we1mew3mimr,:t dsu7fr3 c- oi t a force of 100 N in a dileuc wi-f3 :31, ot/dtimwsmmr7 r1e. rection 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 with a force of 10054 h dfym 5wez ip9jaccuz16/) N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.0 kg, what is the normal force ondhme15/cf4zj)a 5wyp z9uc6 i the box?

  A traffic light of weight 100 N is supported by two rop.gq ivqw1 fj:456qf me;sas(p :tq5(k6jlqzmes as shown in Fig. 4-2. Wha(5q: 5qpaqs v :.ze g1(tf4j6qlwjiksm6fmq ;t are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ro1 5 pin2h/q (0hmdmqdnpes are 50 N, what is the mass of the trafqn 2dn5(1/mmid0hq hp fic light?

  Two boxes of masses m and 2m are in contact with each other on a frictionless n*4z.2dstu d+foyfj 0 .7a3b7t ulvshsurface. (See Fig. 4-3.) What is the accjysuf 0.*4 zdv7.att2o7nhsu3 fd bl+eleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other onsxrf:b0lsw)4vx b(y a5q 4,ya a frictionless surface. (See Fig. 4-3.) What is baw)yqbsyv 4rx0f: s5 ,4ax(lthe net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4. pk8qok*w:,tu) If the forward force on the mpu*tkowkq8 ,:ore massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a ry jn: 7;zdxf) 8x.v 1pna9dg2o jex4okope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massiv j xkv)f4. ao2jdz9yn78x:;e pxognd 1e box?

Two boxes are connected by a cord running over a puzbg*gmyr:zb.e cy6*dx s4cw98o 0q p.lley as shown in Fig. 4-5. Box I of :rd6ysyg0b.wz 8*o qcz*.9pce4x mbgmass
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 sqg p.jp zr88c.tatic and kinetic frictions 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 applied to the b 8ppq zjr8c..gox?

  The coefficients of static and kineti)ct(eqzt+ /q nw( zdj- q7.oyzc frictions for plastic on wood are 0.50 and 0j(zeq w)o/ yqc(.n+ttd7 -qzz.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 direction. It slows and co t/1pxuf0q1rchp1 ag2mes to a stop with ah2qpg/ p 1tr1fcu0x1a 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 horizontal surfacexh *se(o*bqm8be j t(.-xv(pa is pulled by a 5.0-N force. A 3.0-N frictio( 8*pxasotqejv x*(hb(e. m-bn force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates dhvtz,zq92qj8i j xh+. /wk2o 5.qpa xa 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 puck is given an initi7 op6(qvtwd;x8 jy*wto; k5zial speed of 10 m/s. It slides 50 m o ; vpt 8o5qw6t(oy7zw;xj ikd*n the ice before it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident,bk0 dp.ru;mvq +oqpbx*o e7 52 police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing conditions. Estimate the spekqdrpxm2bu qeo7v b5+p . ;0*oed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stackepb(5ufo cp.i/imt;xe j )z/,n d. (See Fig. 4-6.) The surface between the more massive box and the horizoi5f te,pn(ub/o zji/ ;.xp)mcntal 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 surface betweeq5 z9 f8f:a.jiof8pjen 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 bj o 85pz qaj:efi89ff.ox, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined planp4) 9/h mddiy h5oh-y5wohkh*e. The plane is inclined at an angle o 9wy5- p/mh *h)hdhoi4ok5hyd f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an alf g5jze,)h69 xkllo7 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 smooth0 t)) ndqmyoosq)wf*5 inclined 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 smoof. 4hgn6unukgt 7dj,ywak 6p wa06 k90th 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 down an inclined plane, at a c30a: ih.n birdonstant velocity of : rina.hd0i3 b6.0 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 sluuf0 to 5dj/b z7o14g9z xpa zuy+:.foides 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 down a rc + 7cbmd.s6ctay: andl-y).tough $37^{\circ}$ 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 surface.k, .tixxh8q9y The cable attache8,.ik yqtx x9hd to the log makes 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 9/a6wamtq +w yc+ gi5frough inclined plane tilted at an angle o/gyf+aa 9i q5wm +t6cwf $33.5^{\circ}$ 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 on4uzy;lg1qu-;7 - n6mjd orno o an inclined plane. The 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 sj6-rnu ol7u o1- ndz;y4qomg ;tatic friction between the object and the plane?