Which of Newton's laws best explains why motorists shou3tord5ir4 ucp.* ql (sn-.uwuld buckle-up?

  When you sit on a chair,w: k4hh37x-yv-j eiq l the resultant force on you is

  In the absence of an external force, a moving object wilv n2))np x l*pble32x.dns9wvr k,x u8l

  When the rocket engines on the starship NO-PAIN-NO-GAIN ars9j r)40e yvihsu74h xuuj,e4e suddenly turned off,sju4,7 )9vshh xieuyr40 ue4j while traveling in empty space, the starship will

  A rocket moves through empty space in a straight line with con.gom js vk:x(,stant 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 motiosjg.xm,vk(: on is

  You are standing in a moving bus, facing forward, and:)c8b(v rbkn f1zll3u you suddenly fall forward. You can imply from tbbk r vl :13l)(zncuf8his that the bus's

  You are standing in a moving bus, 55: 7cuw :wqik6mmwgg facing forward, and you suddenly fall forward as the bus comes to an immediate stopqkg:: 5cwi um576mww g. What force caused you to fall forward?

  A constant net force acts on an object. Descr+87 ny b.zti:xysr +yp qv2uw4ibe the motion of the object.

  The acceleration of an object is inve*3gahg dly-6zrsely proportional to

  A net force F accelerates a mass ,n9mzxgl (8rl m with an acceleration a. If the same net force is applied to mass 2m, 89l( nlg mrz,xthen the acceleration will be

  A net force F acts on a mass m and produces an acceleration /8r*kgep3 pzz*texz, a. What acceleration resu rpez ,tk 38gp/*zx*zelts if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, t gg .ectfy2/l4he balloon will fly away. This is ael2y t.cgg /4fn illustration of

  Two cars collide head-on. At every moment during t j4:v4irol tsy,g..0.s-yno .cx flfwhe 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 exerts on the first. This isi4jw. ,-lvsxco.r fl0 . : ftn4y.ygso an example of

  If you exert a force F on m4fl ,ni9ep bq3h)po(ucv54+cl,mkdan object, the force which the object exerts on you wip9+l3qmhicp4b4m(e)u o,dkc5, f l vnll

  Action-reaction forceqqf 51aumuw,pk*yl3z 9v5sz 2s

  Action-reaction forces / yi.(swtu:uxwzcphge;4a7 , are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to tecb9l ;p0*jl khe car. Since a lot of damage is done on thep9 l; 0*jceblk car

  An object of mass m sits on a f2zbg0*t 7ic qwlat table. The Earth pulls on this object with force mg, w c*bg 7t2q0wzihich we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceilin3quw qr u:q,)oc 2e m0p(ht.fcg by means of a string. The Earth pull3ech) (om0tuc2r qup :fq,wq.s downward 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 instantaneoup je6lqq qkuk* m1uj.bg0sh67 0z76jbs force. The ball hits the bat with an instantaneous force, whose magnitude.e7j1qjq q m6u0su7l66z* j b0 khkbgp is

State Newton's three lawsi5x1 y s*pq)vd1 1pwrrxx(rj0.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which of tg(a o/pg5/ ln-vt:akphe following is true about the mass and weight of an astronaut on the Moono (-gl p/v5p aak/tng:'s surface, compared to Earth?

  An example of a force which acts at a distance i))xm)f: wabab,lbvfdo z;6 , fs

  Who has a greater weight to macfmy3z2n ua)3hvpe:6ss ratio, a person weighing 400 N or a person weighing 600 Nypu:hev2n) 6z3a3mc f ?

  A stone is thrown straight up. At the top of zq7v)z f6f+pw.p p ekp2vtfu.t(8d-gits path, the net force acting on if6.tpgp7z f(vd28.vqt wkef+up)z p- t is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same heighijwg 41ogv,5hq 8i;wgt. Ignore air resistance. Compare theirqijg 41v;g,gh 8o5wiw accelerations.

  A brick and a feather fall to the earth at their respbl zo1hzn /5qsg6o9h ;axq37u ective terminal velocities. Which object experiences the greater force of air fricti6oz9oah5b;ng3q1 l qzx 7/hu son?

  An object of mass m is hanging by a string from 12sy8k y, 459ecwqltl n;qpguthe ceiling of an elevator. The el g1swutylc 24,9 qp lyq;kn5e8evator is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling ofrhz 4(awchpa2o,79k d, . mqay an elevator. The elevator is moving upward, but slowing down. What is the tension, hq4rmada,oy7 k 2a. hp9wcz( in the string?

  The force that keeps you from sliding on an icy5wbzf rymk* px ql3*e w11;l9r sidewalk is

  It's more difficult to1ji dxob;( j.pn.ufx; start moving a heavy carton from rest than it is to keep pushing it with constant velocity, be .odn jb;x1ip(j.fu ;xcause

  A horizontal force accelerates a box from res2up:zc20/shs r0 mvx qt across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with th/:rs 2p2 0mz0vxch uqse exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclinedikaae+6 ;utl 4 ramp at constant velocity. Thus we can dedu;utiek aa6l 4+ce that

  A block of mass M slides down a fr(f ftp;z,nu* wqt 7uw7ictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the p* (uwt7f7z,f;qptwn ulane on the block is

  A block of mass M slides down a frictionless pla*5d z7,iciwr1z/evch )p pu6 nne inclined at an angle q with the horizontal. The normal reaction force exerted by the pi7u e)hnzcvzd, i/6wcpr* 5p1lane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an a f 3yut,yqdbk9 xuc*56ngle q with the horizontal. The gravitational force 3*u, 596kfbytd cyu qxis directed

  Two toy cars (16 kg and 2.0 kg) are released simul17 (jobuq wadyos,ex *ej x(3,taneously on an inclined plane that makes an angle of 30e with the horizontal. Mak7ejja,q* x wux((bd ooey,s3 1e a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N fqzw7sa3c1 5bdorce is applied to the object, wd5c173z ba sqand it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in 7.0 s. Whatxvba 8qwr9 *6e is the average forward forrw8evx9 qa6 b*ce on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 uomde .w-lg 56v (,lj6(7hoxlyjq:aix h+a a; s. What is the d li7:q xl,aj lwya;6hex o(vmgu + 5aj6(.ho-net force acting on the body?

  An antitank weapon fires a 3.00/b5 w4; amaxsa7(w3htix63vkf z7 dgx -kg rocket which acquires a speed of 50.0 m/s after travelin sxkx7bi wa3/gdvafth4( m6; xw3 5za7g
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 samg135 zcnfvb0 yj5llj0 scq6um a z.i.5e force that you push a 10-kg mass from restz.6j3lg0q5slf c v im501zj n.cbauy5,

  What is the mass of a person who wes 1oz; 9rb a6 s-afkm))co*gchighs 110 lb?

  What is the mass of an object that weighs 250 N on the sur ldckh0v nmo*7i64 f*xface of the Earth where tm 6o*c*0vlnkh 7id4 fxhe acceleration due 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 4ed/vt2 +j 7st:tr ccgobject on the surface of the Moon where the acceleration due to gravity is only 1/6 of that on tsetjcc/4g :tv 2 7+drthe Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on t6j ggyfdrfcn q kv)05fp9.j)9 )a qyz/he Moon. The Moon's )y) jdjrq. /p 9c0fgz6f9)nvg5akfqy gravity is 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 5.0-kgpndmjs d:3t0l*n/2h ;ezd es0 rope. Sue pulls with a 15-N fs*d2hm end:slt3je n p dz00;/orce. What is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests o pwkb,i: ez), j8zfne0n a level frictionless surface. A force F acts on the stack, and it accelerates at w fbnepizj,8k:,e0z) $3.0 \; m/s^2$. 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.jpf7lzu j zjt0/m;i. qa nf// elevator. What will the scale be reading when the elevator is plaft 7;j/f/jz0.q./mi nuz jaccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is he:v: 93eyznzwi k98w 60.0 kg and the elevator accelerates downward with an accelerati:k3zwv9 9:e8 enzhwy ion of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rs8y9 8a3syxcs 0tdij 1ides in an elevator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an accelesdx8sayc 0j1839tyi s ration 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 mxy5j8jkzu0b vll+euu )r go6z s 5v;63agnitude of 8.0 N and is directed due north.vs+y)kl6z5 8b0x5zl6;u3urojvugej 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 f27mj s(,3ll xoipbn03 ctzt n1y(xue:latbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 x2(ts e3:ljlcz(b u73tm,o0xn1 iyn pN. 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 rests on the flatbed of a truck. It is held in pl* pjjzj d c6p7v2tkd(j.2a;q hace by metal brackets that can exert a maximum horizontal force of 9000 N. adv (jp.7k jqt6; jj*p2z d2chWhen 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, wh 1ar,,awi+ sqiat is the magnitude of the acceleration of the system? (Ignore friction aqas+,wr i, a1ind the mass of the pulley.)

  In the Atwood machine4(ko wc3rw fqgk-z7c5 shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the m4kwo- qc 57(3czgkfrwass of the pulley.)

  A student pulls a box of books o)9 lkl, gwycusm deu2h;q6wg3 04ja i2n a smooth horizontal floor with a force of 100 N in a direction;s2ljhuc kmyd w3i)l,6aw9 ug2g4eq0 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 horisxa gbv5g yl+2hrv )wm,1h*2dzontal floor with a force of 100 N in a v,wmbs 2+rxda5 lhv*2 y g1)ghdirection of 37.0e above the 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 is supported by two ropes 2lg hxx (kz1nez( o58zas shown in Fig. 4-2. What are the tensions in the ropek znxzh zx((g51e o82ls?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is thekq*x qhby o(75 mass of the traffic ligyx(kb7q*h5o q ht?

  Two boxes of masses m and lgmtvm-+37th 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What isl-mm3 t7vhg+ t the acceleration of the more massive box?

  Two boxes of masses mrq;7*t:re onmeeaf n/7x.;gh and 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the more m*e:/mrn;g.e h qone fa7rt7;x assive box?

  Two boxes of masses m and 2m are connected by a rope. (See .9h4d* lzahqcFig. 4-4.) If the forward fo q.d*hl4zc9ha rce on the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m anv:by.8gp ,rou ;4muc vd 2m are connected by a rope. (See Fig. 4-4.) If the foruvu8r4co, ; gpv.:myb ward force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley (w e+ozl0zab* k9he;3nmx rr7 ly8l3mas shown in Fig. 4-5. Bom;+8rbxez7(w9ylra3hlme*lz k0 on 3x 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 kinetick)s kd;,5tg4yo m yp.o frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the .)ykoogys t,;k4d5 m pnet force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictio wh (qsae9xxc, k2-(xfns for plastic on wood are 0.50 and x (s2,-hq kfxca9exw(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 leveuz1ks/k eu/3 il surface in the +x direction. It slows and comes to a stop with /izu/ek 3su1 ka 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 surface is pulled by a 5.0-N for wz - bawnv1g+4b(lghd*o2r z8ce. A 3.0-N f+1nw4gboahgz- l d2* vrwbz8(riction force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a rate oftae dk(1r6 k.z $0.50 \; m/s^2$ in the positive direction. What friction force acts on the mass?

  During a hockey game, a puck is given an initial s3froj nyzi21 3xr,yd0 peed of 10 m/s. It slides 50 m on the ice before it sto 3jo2d0y, rfnxrz1i3yps. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 90.0 jl xi,e8-p ap5m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.500 for the prevailing conditions. Estimate tlpx- ,i5a8pejhe speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The snff* q hqyzqlrbqcj,l3,3 0,. urface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the les b,ff*qj hcn q,qy lz.3q0l3,rs 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.) g7 co73(v csbq15t zuw The surface between the more massive box and the horizontal surface isusq( t17ob3g5wcv 7cz 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 friction between the boxes?

  An object is on a frictionless inclined plane. The plao6eu: )bl5ph x4g0k fwne is inclined at an angle o ghbxek0 :u) f5ol6pw4f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flatprmb-);mcm:q9y)w sy cto 4(o 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 angldly kg26m8)d5vwc (x6.xvotce 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 ana 9tw:2rm+vv e 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 suh kpp6 8 ;;0;dh+b v5tf bzhd3v+zajifc49eplane, at a constant velocity of 6. a phb;60 sihf;vht4dup;39z5fzb8 d+kvcj+e0 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 dod2x pp+,u j( ui2edmjutg148ywn 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 g d4w3ck *c 8;j6aksdprough $37^{\circ}$ 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 alongpd q m)wihm7b*2f c3a qd(;ej6 a rough surface. The cable attached to the log makes an 2mea3 *qhd7ijqw f)cd ;pb (6mangle 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 tilteds.of ml . u,5tmg .pc3d-u(ied at an angle of g,t c3peu(o.lf mm.-5dusi.d$33.5^{\circ}$ 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 ano eg6(6af+ inj inclined plane. The angle of incline is gradually increased until the object begins to slide. The angle aea6go ijn+6(f t which this occurs is q. What is the coefficient of static friction between the object and the plane?