Which of Newton's laws best explains why motorists should buckl*al)v: )9 v kesx.pbfwe-up?

  When you sit on a chair, the resultant fo ;z,p+ 9cc fc jn,l*d t+nrs.nom;q9ojrce on you is

  In the absence of an external force, a mom7;o0/wmgus9up ;kx q nc7k1bek9ql5ue2h 7vving object will

  When the rocket engines on the starship NO-Pd4z qn,sb6 htmjpe5/( cvvy/;mh+kw ys )h+(j AIN-NO-GAIN are suddenly turned off, while traveling in empty spac/h svebq ht)s cy6 4pkjzv/y,5dj+n(hm ;m+(we, the starship will

  A rocket moves through empty space in a straight line witydh1 yq 71 btpv)-tt9s /iccs6h constant speed. It is 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 -tyvqib t69y7 s t/cc)1 sd1phis

  You are standing in a moving uz18de52n scb bus, facing forward, and you suddenly fall forward. You can imply from this that2 8sunbc5 1zde the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall forwar3lniyrbnerv *)9 0ap )es5j *yd as the bus comes to an immediate stop. What force cause5sil)j* er 9 rbay30 *)nvpyend you to fall forward?

  A constant net force acts on an object. Describe the motu0cs f-/h z5zuion of the object.

  The acceleration of an object is inversely proportional t7 h p8 )0ki(dqg6j7eylhnmf0co

  A net force F accelerates a mass m with an acceleration a. If the same net fordl.y ekt03 : + qib kuttng;)a+ygxd;7ce is applied to mass 2yqnbttugd :k+.l0y di;e 7)agx; t3k+ m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleraybwc0n8c uu+)nbh 6 ,nck;:dation a. What acceleration results if a net fonc buy:;,ka6 n8cbu+cdn0h w)rce 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the1::e smm ws2kc balloon will fly away. This is an illu :2c wms1em:ksstration of

  Two cars collide head-on. At every mij/vrrh*znxl ,w r55fq6v64 o oment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitud6 n5h* 46z,l5wf qj xiov/vrrre 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 ym0zzpgbl +-l 0s1xjh zi2wpj +p7/ sp3ou wilpw ijlh0p2p 7-z l0+1 j gz/psxbz3s+ml

  Action-reaction forceb +lqzdw+3bz/w2v. owwd) u leah9(:vs

  Action-reaction forcesb+n 1qh0lh+(f:avhr m are

  A 20-ton truck collides with a 1500-lb 7 h:2kpvers6u l .lwymn(5lv5 car and causes a lot of damage to the car. Since a lot of damage is done on the cahpuk lls (v 57:vem56wnly r.2r

  An object of mass m sits l)thunf3ym:e9i l h,+ t;ki+qon a flat table. The Earth pulls on this object with force mg, which we will call th3h9:ii+n y+;hmut l ek),q flte action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earth h/;pp8f 6t ntgpulls downward on the toy with its weight force of 8.0 N. If this is the "actio8tg ppfn6;t/hn force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. The ba -7gz8rxq m7ssrok :6wp3ws 0jll hits the bat with an instantaneous fo3xj-78rrk 6 zssswp7qgw :mo0rce, whose magnitude is

State Newton's three ch4t: 3wb0msu:+rvd(b 3c7p pyns 9tu laws.

  Mass and weight

  The acceleration due to gtr9 c(hmrq3 6mravity is lower on the Moon than on Earth. Which of the following is true 9tr 6mchr 3mq(about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force wz )1re x0cr/nqku0t;ehich acts at a distance is

  Who has a greater weight to mas, hign/c s8:6s1vh5 x egfvy0 /s:vuwss ratio, a person weighing 400 N or a person weighing 600 N?sv1: xuswf0s ni/vhy8e cv6,g s: /5hg

  A stone is thrown straight up. c3e; j:grfz7oAt the top of its path, the net force acting on it 7 j3fe;grz:co is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same h:7b/3 arde vgteight. Ignore air resistance. Compare ther/3bvt7 eag: dir accelerations.

  A brick and a feather fall to the earth at their respectib lje. sxfpt4n 8/-kk6ve terminal velocities. Which object experiencex pet46 8bsk/j.fnlk- s the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling 9ku(l*t zcs k5of an elevator. The elevator is moving up at constant speed. Wz5 u kksl(t9c*hat is the tension in the string?

  An object of mass m is hanging by a s w0jy6vx5g hanzo :/khu;n2f8tring from the ceiling of an elevator. The elevator is moving upward, but slowin2j8:05yvok6wn/fa ; uxhgzhng down. What is the tension in the string?

  The force that keeps ip,0 qtk4kq/ jyou from sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest thuz4)hse kr gd:e5k5cm(5n zj5an it is to keep pushing it with constant velocity, beca z (k zcsmjue4g5dre5k5:hn)5use

  A horizontal force accelerates:f6e: (hw -j0oemxcwtl3jq/8(sz j vo a box from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remaj-e :wf 6: ejocq 3z/(8 vlhso0wjmtx(in 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 ramp at constant velocity. T 631xvj:xni hyhus we can deduce3xni yvxj6:1h that

  A block of mass M slides down a frictionless plane inclined al dm:nz+j l0e ,(ko7jrt an angle q with the horizontal. The normal reaction forcekl7eo+ :nl(d,m 0jzrj exerted by the plane on the block is

  A block of mass M slides d)a1lbb yml2 lor u85vf5ze,-uown a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plauvba 525 b)yuemflz- l8o1rl, ne on the block is directed

  A block of mass M slides down a frictionless plane inclilovv *5g i4gd8ned at an angle q with the horizontal. The gravit8olv gi45d*vgational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultanf6pxj,ix9 v;f4a0zah eously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describeipjf fhav,z4x9x ;6a0s their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applie1d)ux* hwg7ukvibi /.d to the object, and it a)wg7b*u dx /vu.k hi1iccelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from reswlxw tq(/qa;7 t to 27 m/s in 7.0 s. What is the average forward force wwq(/t;qlx a7 on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What jot g inax(;f )c*)do3is the net force acting on the bodfg)i(xo)tdo*a ncj ;3 y?

  An antitank weapon fires a 3.00-kg rocket which acquires a spjurs.w 1cbt;yx.8 m9t6 vm js0eed of 50.0 m/s after traxv.s 8j0 ;s .by1uw9cm rtj6tmveling
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-kg4h :v573nketukw0a 2dx7zr ih mass with the same force that you push a 10-kg mass from resa7x k3h2z wunh7i:e0d45r tvkt,

  What is the mass of a person who 5.h3iyko( pa k0 im 7f;+boknuweighs 110 lb?

  What is the mass of an object that weighs 250 N on the surfahq6ls5k. q8 jkce of the Earth where the acceleration due to qsl86j.hk 5 qkgravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Ea bx t/nbd(gr70rth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 ofbb0/7x gdtnr ( that on the Earth?

  Object A weighs 40 N of4k;en c hp9yu r73tr wt5mc79n Earth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of trt ;7kp 4ecn3f9m59hcrytwu7 he objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5.0-kgnkkxn)j ax7* . rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward Sun k)x* k.7ajnxe at $2.0 \; m/s^2$?

  A stack of books rests owihr6m6. 1lbz qo85e-lw h:pm n a level frictionless surface. A force F acts on the stack, and it acceler .mhqp elhwlw:b-r 8516i mo6zates 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 e ul0-aqcv sriw ;:k/1xlevator. What will the scale be readsqw:i-x0; r/lk1vac uing when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevat h m+gpy/vv;h qu8)e;m (6ceynor. If the mass of the person is 60.0 kg and the elevator accelerates downward withmvhye n+c8;emqy upg(v )6;/h 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 persoe4taungrniq.l/ 9 0u4fc f/)p a 23toan is 60.0 kg and the elevator accelerateu a3t/ il4q2ff).ane cn/r pu90g4otas 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 has a mat86 o,vdnyir; gnitude 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 acceleratidy8to6i, nrv ;on of the mass?

  An object of mass 6000 q6r9hg civ 67wop1t g5kg rests on the 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 traveling1who7ggr 9 5p6 ctqv6i 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 restsacu)m+t2q,-8myv ig(h mssp / on the flatbed of a truck. It is held in place by mets+8)i y2pm ,st /cga-u(mvmq hal brackets that can exert a maximum 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 and m = 0.40 kg,. r,o1;8lorpe rrp-d qzvb *n9 what is the magnitude of the acceleration of the system? (Ignore -q.9ponrd;rz1 *p 8rv rolbe ,friction and the mass of the pulley.)

  In the Atwood machine shown l)yrx bzh*xj6;o+:2 sqf3/fq selp8w in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore :2qf3xfq* ws ypzr)ebjsl; o8+6x/lhfriction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor w0g5gr9kkzu ,rw p-t.eith a force of 100 N in a d-5,rpzrekug 9 wg.0tkirection 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 * muoixr0.+hwwith 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 kg, what is the norma m0o.u+rwihx* l force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown i mi*hr*h08bf0bbj ,e zqf18bjn Fig. 4-2. What are the tensions in t f b,0briq81hb eb*80*fmjz hjhe ropes?

  In Fig. 4-2, if the tensions i*b;pe zhegt:4 n the ropes are 50 N, what is the mass of the traffic light?zteg4p b:e;h*

  Two boxes of masses m and 2m are inr763 ;t36zek cudx atp contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleratt ;76363katz puerdx cion of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictio ,jjf*wtnr. 1unless surface. (See Fig. 4-3.) Whaf rnj ,*w1tju.t is the net force on the more massive box?

  Two boxes of masses m and 2m are connvr5dr/,ka7xt4f;80gpc )qexta z mq4 ected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the connecm0tqaztrga;7 4)d,px ke8xv45/ qcrf ting rope?

  Two boxes of masses m and 2m are connected by a rope4a+yz/dd tl8n4xyaq no h)p01. (See Fig. 4-4.) If the forward force on the more massive box is F, what )dntla1/nh0yzp8d 4q+o4x ay is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as e7la* b:wo)d lshown in Fig. 4-5. Bwbale7:)ld *oox 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 3.0-5lac vke ,jj9*kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 1vkje 9a* c,lj55 N horizontal force is applied to the box?

  The coefficients of static and kinetic fricr5n slb;+;c fwtions for plastic on wood are 0.50 an lnbw+;fr c5s;d 0.40,
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+eo (oqvdt4. z and comes to a stop with a constant acceo. 4+zqev d(toleration 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 s-y xb8 ;ep29pua m-g.t5pqsna 5.0-N force. A 3.0-N friction force retards t2pm-qs.gy;-5bt pesaun89xp he motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest,,1) d9nfm mbzmquff,6u+0, l vc hc:fj 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 initial speed of 10 m/s. It slides njl k3) l n-5n0rvhm7a50 m on the ice before it stops. What is the coefficient of kinetic friction j7mn-n)3av50l krlnh between the puck and the ice?

  During the investigation of a traffic accixs+ qe5*o *lzu8g /ezgdent, police find skid marks 90.0 m long. They determine the coefficienezqo/* ge5 +lu8z *xsgt 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 applied.

  Two boxes of masses m and 3m are stth-2xkr5z+ml -lt.f kacked. (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 .th--mt5 lfxr k+l2zkbox 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. y d9 /6qps:hlf (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 6/sfd lyp 9q:hmassive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclineo) 0fo ;ncsb0od plane. The plane is inclined at an angle of0o ;ofs )ocb0n $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides dow /8 p)5 w(uohk;do j(pvx,dmdln a flat 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 shb79;amk(g)upp(o g 3kxuc8 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 inclined plane tilted at an angle of wa ,g9ce9wdfwnw3b9kk1: pi) $35^{\circ}$ 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,gu/t+nv g44)m. cwwy *tt f7bd at a constant velocity of 6.0 m/)g tufgwc t 74w t.d4/vbyn*+ms.
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 s3b0 c yqogf8:ye.xuhef6rg-: lides 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 s6e s ct1svh.0jlides 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 surface. The cable attapxndny 9/r/+uched to the logdy n u+9//xnpr 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 res5adf; (,w cjq1l :kkyw5e7mklt on a rough inclined plane tilted at an angledjm, k1ak:flqe5 ;5w7c kl(yw 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 wj j ebl;p5p(8p sc-e29sgw bj0ib1,pon 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 between the object and the p- bpb1 p0e,wj jbcpw(58;9pe j 2sigsllane?