Which of Newton's laws best explains o7)wmzjhk *- iwhy motorists should buckle-up?

  When you sit on a chair, the resultant force on yoj ri 2kicbr1*m0) mz5 ysd*e(iu is

  In the absence of an external force, a moving object 38,k z bckidk(will

  When the rocket engines on the starship NO-PAIwo )m)p y fsjgl9v02rp-*zm-g N-NO-GAIN are suddenly turned off, while travell) pv-)ws r90-2gpgm yfzmo j*ing in empty space, the starship will

  A rocket moves through empty space in a straight line with conn ln i)9u*2lgl yued13stant speed. It iuy nin21)9legl *ldu 3s far from the 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 a moving bus, facing foj)*fsw+2y8yrxl nx a(o mf 3q+rward, and you suddenly fall forward. )(f nqo2fy8x+saly jmw*+3xrYou can imply from this that the bus's

  You are standing in a moving bu1yb(dwfbeu l v: :lkkq87 5(5;krk:vn 2ypcyms, facing forward, and you suddenly fall forward as the bus d: ;q5pl 7u( v:kkk8l2mf:bcw1yybvke ( n y5rcomes to an immediate stop. What force caused you to fall forward?

  A constant net force all-mt 7 4i5v9h a9p8l4 6s-kbqlhrnapcts on an object. Describe the motion of the object.

  The acceleration of an object is inversely proportru)co+5 c6) loza9 ro04yybjxional to

  A net force F accelerates a mass m wzrth v 1bc+8q1-nvgoje1lz3y9a e+/u4v3pw with an acceleration a. If the same net force is applied to mass 2m, then the accegev-4v 931l r1h 31zju8qe+ vtywc+p/nb aozwleration will be

  A net force F acts on a qm 6/q2l;x hz 8sdpno+k;-dfa mass m and produces an acceleration a. What acceleratiop h+zq8xok mq-2f al6s; ;/dndn results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then rel;r nzg2jnl4;aease it, the balloon will fly away. This isn;n4a jr2lg ;z an illustration of

  Two cars collide head-on. At every moment durkw;;n73 wuupmvynu ; :ing the collision, the magnitude of the force the first cu;v;ynnk 73ww uum: ;par 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 an object, the force which the object66 vx*pj(hcuw exerts on you wilpw u(x6vh*jc6l

  Action-reaction forceswjl pf rzjb)(4n/o z-6

  Action-reaction forces wy8h45 ymnon:; *;m ufo5 oruoare

  A 20-ton truck colli- -itatm j qnek9ma2-8des with a 1500-lb car and causes a lot of damage to the car. Since am8maij--t2ntak 9q -e lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this object withb ;i45 ;hgbutl force mg, which we will call the action force. What is the reac;hbg5ibl u;4 ttion force?

  A child's toy is suspended 4ts*;czwdt,z z)8s lc 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 "reactiond lcz),s*csw 4z ;tzt8 force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. zmo,-k* qkeu ha9c08gThe ball hcak hgqz8o,m9 keu 0-*its the bat with an instantaneous force, whose magnitude is

State Newton's three 0z5 d6pl+ ;:*pjao pg.hcslcy laws.

  Mass and weight

  The acceleration due to gravity is lower nj8o39e/sqvix d-c) don the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Ea svqnj ci-e o3)x8/d9drth?

  An example of a force which acts.l y dd9si549 ,lrtro eu*kz2z at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a persom:rx f3v -xa6an weighing 600 Nx afam6-rv: x3?

  A stone is thrown straight up. At the/yq1 vedk inr.)ui;,k top of its path, the net force acting on it, .dv/ikyen ki;1)r qu is

  A 20-N weight and a 5.0-N weight areup5rws/3 rg*yg2qs,6 c,os wg dropped simultaneously from the same height. Ignore a 5 ,g3 6w/rcwysg2s,qrspguo*ir resistance. Compare their accelerations.

  A brick and a feather fall jbdh86)bn 9xc3 e;tb cto the earth at their respective terminal velocities. Which object exper8cdn9xb)b hj63 eb;ctiences the greater force of air friction?

  An object of mass m is hj0qzefcv2b: kjsd) j2 ju -w(6anging by a string from the ceiling of an elevator. The elevbj w skd2f:qceu)j0z j- j(62vator is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a st icbdz6(uh /0d 5m6vhxring from the ceiling of an elevator. The elevator is moving upwardzcmdu b0 (dv66h5x/hi, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidewvhbsq- rn8/e4alk is

  It's more difficult to start moving a heavy carton from rest than it is to keepminn )rz;: 1jcp rkk.1 pushing it with constant vel 1p)imnz:c .rjk1;rn kocity, because

  A horizontal force accelerates a box from rest across a horiz-tbpn wu ;2xp9zzu98xontal 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 iszu8tuw2x n-p 9z;9bpx doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus we cqkei) o / 4xe1/xl jl*vejy*k,an deduce the4x/el /e,1y* xojjqv li*) kkat

  A block of mass M slides down a frictionless plane inclined at an angle q gj l1j,7. e iimcr-yy/d c1m.pwith the horizontal. The normal reaction f/7y c-i.i1m ,le1dgjcyr. pjmorce exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclinh yha1vp.n( jld pikjqj 4akyl*:54 4/g; urq9ed at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is direcajilp.n4yj yp4;l :vq9aqdg* hjk 5hu (4k /1rted

  A block of mass M slides down a frictionless plane inclined at an angle q :,b/ giwyux: zx)5xsfwith the horizontal. The gravitational f::, 5fg)xs/uywxi zbxorce is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined planxh577ftylk (te that makes an angle of 305 xtlf77y(thke with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a m2he(h63ay.g-g5v7w: (tcrupu rycffrictionless surface. A 16-N force is applied to the object, and it a(:p36u7ym5g2g ewah -ucfr(yvt .h rcccelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from /d39 qb imwu)xrest to 27 m/s in 7.0 s. What is the average forward for ux)3wdiqb 9m/ce on the car?

  Starting from rest, a 4.0-kg body reaches a sp1. csr+5g zhnk1ezn 6weed of 8.0 m/s in 2.0 s. What is +z.1ezs nnrh 1wgck65the net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquir k+eyc(8, uo7,p+y fckqihec)es a speed of 50.0 m/s after t)fyo 78uk pqeycc +,ie(c,h+ kraveling
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 force2 zf 0.cicnvu) that you push a 10-kg mass from resvc. )2u0cfiznt,

  What is the mass of a person who weigh k jehap7o 4v63sfh(l)s 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Eka(wekxi +z6lx10z2( eldn c +arth where the acceleration due to gravit2cl x z exle(w+z+dai1knk0( 6y is $9.80 \; m/s^2$?

  An object has a mass of 60 2ft.jbjs:.o o- ru0 cqkg on the Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of .qob:ujc f0jts.o-r 2 that on the Earth?

  Object A weighs 40 N on Earth, andyce1eai0*gg u /:o7wa object B weighs 40 N on the Moon. The Moon's gravity iuioe0ag*a/ce1 g 7w :ys one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5cs 8* .l(o pukrksi-c;fb8q*y.0-kg rope. Sue pulls with a 15-N force. What is S *upfb sl*.(-8ksryccqk;oi8ean'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 bovrs,u2f9r ih(*cl a; +2n llF acts on the stack, and iba 2 inoc 9u,s r(+hr*v2lf;llt 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 y +-vs 9/ys07 giprvrtN stands on a scale in an elevator. What will the scale be reading whvsts/ 0i-pyg7+yrv9r en the elevator is accelerating 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 k f4cc2-5ul qhy )rukn,g and the elevkr4c-uqy u l5ch,)n 2fator accelerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides inzxc*fmho71xb8 /g d 5q an elevator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an acceleragq *dxz/oxhf71b8mc 5 tion 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 msxn +s .z8u1sbagnitude of 8.0 N and i+8zu1n bss xs.s directed due north. 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 truck. It is 3;smy/ ta x9vfqz0l2i held in place by mm9zf /l2itsqv3 xy;0aetal 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 into the cab?

  An object of mass 6000 kg rest*r1xynlf40yaxq fm)/kz27zs s on the flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. 7r*l a1fy 4/fnsqkz0mz) x2yx 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 injn9ei+2 ;1avonomz .k Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of t2va 1 neo.mj9zo+ink ;he pulley.)

  In the Atwood machine shown inqhe3n avp77ld9i (f- p Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is thd79(ehpf3 lvi -n7 qape tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with lfd)v np0,0hl956fg rs- eqcka force of 100 N in a direction cfgrsev0f6q,dh-0pln 5k l9) 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 fq*9h lv+ l5j,3 phgsovorce of 100 N in a direction of 37.0e above gpvhv5,3*qlo h slj+9the horizontal. If the 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 isfgs 7 uepnw7o e8-a3+z supported by two ropes as shown in Fig. 4-2. What are the tensions in the+78po s7za3eu- wn gfe ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what i) 2;7jrjw1ea a1 axwygs the mass of the traffic )x ayawrw1j1 e2;gaj7light?

  Two boxes of masses m and 2m are in contact with ege(m3 e2c3h 3mp;ib6vnp 0am 01pna v)2iexpoach other on a frictionless surface. (See Fig. 4na0 2 mvcxeo(3p6i )eig3n pma;pev0mph1b23-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m ar( dia ehjh+qa.9n-88u9wey hib3p2d ce in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more mas phhd9je(iqacyd.u8i8eb w 3a2h- n9+sive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. j n 5a3a7gl*mfdce a714-4.) If the forward force on the more massive box is F, wm anac77ld *3fgea5j 1hat is the tension in the connecting rope?

  Two boxes of masses m and 2m a r1/ xptmlqk.wn8au wvh4;hl 3own+2*.j psr8re connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is .w38nrjpaqn l+.r 4 /wk2hmvoxu1wt* s8;ph lthe acceleration of the less massive box?

Two boxes are connected by a cord ru we gvn6;vfmk n5yn5-9ge-7 ocnning over a pulley as shown in Fig. 4-5. Box I o55v eg7nc ym-9n gnve owf-;6kf 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 ehp3 tb 123.bucik vrdx,nfw) l:d;s8a 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 horizontalpc3ed 3r ,2sbnxtu8:l hiv1wb.)fd;k force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on kkylqsg2ssm9 p ;;7a8 wood are 0.50 and 0.4 k89;sgp s2qsyka;m7l 0,
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 anxzm2 z+h7*xaw qj7q7id comes to a stop with a constant acceleration of x+7q7 zhzia2w *7xjqm -$2.45 \; m/s^2$. 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-N6;gmk;qkr;0 bc1awmd force. A 3.0-N friction force retards the motion. What is the acceleration of the objectamdgbk6 1q w0;mk ;cr;?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from r(c 3rtcz rrn8dpbl -;3est, 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 ibwydi0iv 9si)e b4sht8 5j,+qs given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. Whv yiebdsht59iisq8 +40jb, w) at is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident,jzr )p3z9 demjuwx3aw (uiuug3 3;5 /.qs5zvr 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 speed of the car when the brakes were apwuzuu)raxpwu3mqz3i j3(dzv 9 rej/55 ;.3gs plied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betu.kuh+sac.yz9r 3/v 9iw ox:bween the more massi uyx3k9/ owau.bs rhz.+c9v: ive 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 and63rd0*km ta jud(5 crj 3m 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 *mr( t6cra3d jud5 0kjnot slide on the more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined hc ei.t1wlr1en;*n e3plane. The plane is inclined at an angle ofh3t;r .cn e11i*ewenl $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill tg +ik2 p:aj5r)b1d c+rnb:tg3snjb)shat 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 ki;0*wy za/iyd.* ;w (poj hxhg+qt1wplane 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 smooth ing fq-f9 7uepka15as0i clined 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 constasdbp3. y:jw9ruc wz +r:zpk *,nt velocity of 6.0 z: :,w.p 3+ckjrpwsur9* byzdm/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 ad7wplabh-8g :8yjo; p 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 xvg* 1t*.oogz 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 surface. inh7s84 4ikz j The cable attached to the lok4i8hsz4inj 7 g 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 re p+i, nf efe/7 4i a lf3d/d;walz(0gjj8wp-zxst on a rough inclined plane tilted at an anglef43 gdfwepj/fwzp + ,;laiz/nj08d-7a x(eil 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 );v0eqgj qwk)bw i7.l 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 static friction betweenv).ewgj q) 7ilwbk;0q the object and the plane?