Which of Newton's laws best explains why motorists should buckle-up3cbnzg p75ts :5hr3 zv*onax 9?

  When you sit on a chair, the08 tw7o ,)y;yvfwxxmx resultant force on you is

  In the absence of an external force, a moving object w)ie89ejo lpr/7)2 gd1msbq0. kawrr mill

  When the rocket engines onhyj) sc-:qlm3bgwxu 6 n20/ f17chmou the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starship wu b3j mf :-1o)qc 0nlyuwgx72h/sm6 chill

  A rocket moves through empty spac,yznul2t 1h;2hq: m vb)g k)lie in a straight line with constant speed. It is far from the grayi: ) ;th g kh2vz,nulqlbm1)2vitational 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, facinx vtx uo(e8xa7i-9/ khg forward, and you suddenly fall forward. You can imply fr/(tuo8av-ek7 xx 9 hixom this that the bus's

  You are standing in a moving bus, ft:0cpn:c2 gwp acing forward, and you suddenly fall forward as20cp:cpw g: tn the bus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objeky6cb,i t ;wt;kd7+ xnct.

  The acceleration of an object 0ow,4; *wiql87m n3xihnq7 wugljr .ris inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the.v gl/cndp9xg3m qpr 4*ap.+cdr5, z o same net forc9pq d.d/rp nx435vpcg az mrgo*+.c, le is applied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What accelfko qxw2n9+( xeration results if a net force 2F fn(kw9o+2x qxacts on mass 4m?

  If you blow up a balloon, and then release ij -ig 9-p/myigt, the balloon will fly away. This is an illustr9p i/-ygjmi g-ation of

  Two cars collide head-on. At every moment durinnaz q f8*6;m *y.xlnbqg the collision, the magnitude of the force the first car exerts on the second is exactly equafn* ;qay bnmx*.6 q8zll 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, 4 jrbgks hk;0ozu:;l4the force which the object exerts on you willrk;ub:oj4 lszk;40 gh

  Action-reaction forcesn .. nlqtek,u,s ir0gs(cw* ;h

  Action-reaction forc vaw)uedet+i2;9xiw- h ygesj:-k42d) gzvj5es are

  A 20-ton truck collides*v rnpb k)m*fq0 :9,u ocv(9nbdfy 8ch with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on u fd* 9 fm*kv,co (9qrhpbnn8b:yc0 )vthe car

  An object of mass m sits on a flat table. The Earth pulls on this object witoha127nn5. nj bdm f h6wv/;vrh force mg, which we will calla; nj6vdbr1n ov. mwn72hf 5h/ the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Ealsjrag4 (*g .krth pullssrg jl(k4a.* g 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 instantal oj6d)lugb0x+ / y,vjneous force. The ball hits the bat with an instantaneous force, whosdj)+/l xvy, ogjb06l ue magnitude is

State Newton's three lly h +v(ugtul+yq99i ch5l(8oaws.

  Mass and weight

  The acceleration due to gl rk.:tfei0 +wkq4jah685rkoravity is lower on the Moon than on Earth. Which of the following is true about thahkljei 0586.+k 4wqrf:or kte mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a forc69h:ai9tth(+zltk arb;l8l yx-aba0e which acts at a distance is

  Who has a greater weight to mass ratio, a person wep:vkg ++8k lf.gwjyd:* 2 wphrighing 400 N or a person weighing 6*+. p: gdg:v2hkywflrwp+j8 k 00 N?

  A stone is thrown stlo n ,xoo78*g d2a*wn/ic bi(jraight up. At the top of its path, the net force acting on it isn/a,*8 2wdigcn*ox i(7bo jol

  A 20-N weight and a 5.0-N weight are drop u-p+sd 0edzq)s43qf aped simultaneously from the same height. Ignore air resistance. Compare th)def4au-zq+p0qs s3deir accelerations.

  A brick and a feather fall to the earth at their respective termngefz( ub2.:n inal velocities. Which object experiences the gre2 z gfu.bn(:neater force of air friction?

  An object of mass m is hs7xw+ :on5 1oblbtji ,anging by a string from the ceiling of an elevator. The elevator is moving upi,7:+oblbt1 ons 5wxj at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling hrlrk yk,;ba )g*8x) zof an elevator. The elevator is moving upward, but slowing down. What is the tension in the string?g,br ) 8khl kxyzr;)*a

  The force that keeps you from sliding on an icy sidewal x jush,,yc z/6hoaq0/k is

  It's more difficult to start moving a heavy carton from rest than it is to keep 0 b(idl6qup84lsf9--yd q z xbpushing it with constant velocity, bec0usx dqb84qd(b -l6p9zl- yifause

  A horizontal force acce0;wxv fg(doz rlml6 fi21 -8wglerates a box from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the dvw6l0 f 28- 1 gmgxr(oiwf;lzhorizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclinb* kego:7y s;g bli)+1 ,7gciiue /uxved ramp at constant velocity. Thus we can deduce tbgys*e ;/1c7g)+iek: lbgxvuou , 7i ihat

  A block of mass M slides down a frictionless plane o2g r*ldm:ws j3k7l3vinclined at an angle q with the horizolm7k or3vgd2 3:l js*wntal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictih6e)b6qr t- btonless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is directedqbtte-6b 6) hr

  A block of mass M slides down a frictionless plane inclinv+six sn2, :uzp69sgaed at an angle q with the horizontal. The gravizav s npsix+u2 :gs,96tational force is directed

  Two toy cars (16 kg and tflq)sy*o) qp9b4h o) :pzk8d 2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e witoho))p*8 ty:zfs )kpbqdq94 l h the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is appl1 ,p5o-wrbf z9g/iu el4cc /puied to the object, and it accel4u,1opruwgp f c-5/cz l9bie/erates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 j dr+ f+x8 vgh.gakq:;kg can accelerate from rest to 27 m/s in 7.0 s. What is the average foghr:gk+;xvqad jf +. 8rward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. Whpz(vj;oec1z1l 7+hdb q, l7 bfa0/n bwat is the net force qbz71 p caf,el +/bh ;lzj7v(w01odbn acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acqg c0 b1(daid4nuires a speed of 50.0 m/s after traveling0b i4g(dc d1an
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 withiv2ca0 co6fu/ +0brbp b lu2b9 the same force that you push a 10-kg mass from rest,opbu6arfvcl02 /i0u cb2+ b 9b

  What is the mass of a person who weimiqbj0lxe: m ejti/rni)90x w0q +5f :ghs 110 lb?

  What is the mass of an objecwaghu:g 491v kt that weighs 250 N on the surface of the Earth where1uh: 4g9 akwgv the acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What i*2aapc;u rjz ,ds ./jus the mass of the object on the surface of the Moon where the acceleration due to gravity is only cu/, 2pjz*uaajs;rd .1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. - nl;ye5 l +8r y7fuplh mc-qf2jup+x8 The Moon's gravity is2fe ufu 8c +lmpp;8jl+yqx-nh 5ly7-r one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tu hnruzh()s0 j+kghr0 ho86z7bg-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if t zj( 0buhzn7+k rh)86o hgh0srhe rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books res9s niu*eg-v .dts on a level frictionless surface. A force F acts on the st*se .v9-ng udiack, and it 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 N stands on a scale in an elevator. What will the s*dl*(bj ,re si )rx9chcale b drje )b9lxhcr,i**(se reading when 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 kg +*ra;-sd6mmfymx wr:and the elevator accelerates downward with an acceleration ofxds ; -mram+f6:wry*m $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. Ifeim8 z .lw(wsaff *wtdjf9b.2;(5qcm the mass of the person is 60.0 kg and the e.8qf ml(mw5*t fzdei;jacb(sw f2 w.9levator 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 4.vnb+lp p4mf 57 z v4uc9ictvforce has a magnitude of 8.0 N and is directed due north. The second force toward the eas5 fn47pm+cb9ptvzv4 c.4v liut has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kzmq *r4t b1y2bg 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 traveling 15 m/s, what is the minimum st1mtb*2yzq4r bopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of mln pl86ug/:l rj8kz -cvj)r2gp/px 7a 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 time if the load is not t6:/n k/p2) rlrg87glczjv-ju pxlm8 po slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kgjgr9*7 8pg jolxzr 5s1, what is the magnitude of the acceleration of the s rs*rjp 8gx1o7z l5g9jystem? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if0a/pmcw l9xj: M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of 9p0ax: lmj/c wthe pulley.)

  A student pulls a box kblc n-(u4uub;3*kz h of books on a smooth horizontal floor with a force of 100 N in a direction onb3u kc u;*huk(bl4z-f $37^{\circ}$ 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 ofjygjvf2+ffk, f3;p 4 x books on a smooth horizontal floor with a force of 100 N in a djvf3f+f ,2k;gf4 px yjirection 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 as shown in Fig. 4-2. gie; vnal;e 9qk-pf). What are the te.va;kfleen9q-gip ); nsions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 5+m5j5 v rnckstojf 022ksbf:f2w k*t8 0 N, what is the mass of the traffff k2t owfs5tks b08mc5vjnrj2+k2:*ic light?

  Two boxes of masses m and 2m are in contact withl/ c0l2o/pzrs each other on a frictionless surface. / lps2c/rzo0l (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionlew nk44;u4ua3wad ;zkass surface. (See Fig. 4-3.) What is the ndna;4a34 ;w 4ua uzkkwet force on the more massive box?

  Two boxes of masses m and 2m are coy,3o u3-pukyhks 6rc7nnected by a rope. (See Fig. 4-4.) If the forward force on the more massive box-o k3 ,67suhy ypck3ur is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are c7lq/hn;one 9n onnected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massivoln/h;ne 7n9q e box?

Two boxes are connected by a cord running over a pulley as shown in Fig. l7u+)fs y8 znb4-5. Box I7l 8 uzns)yb+f 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 da* pp 6k((z-+ r s:dd,t0cnyztv1teybetween a 3.0-kg box and a desk are 0.40 and 0.30,p z(zcak,ddp(sne*d r 0y6-t: ytv+t1 respectively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static anday;zval (c,j5 q: ht()x ikeso8:h(vu kinetic frictions for plastic on wood are 0.50 and 0.uva:5exhqzj 8o( h(:(k;acv)lsy , it40,
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 andl-ayi7 6 i,.-rxhqhw 3x ;yavq comes to a st qxhlrhaa,qi.3v 7 yi;w-x y6-op with 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 horizontab2alj4 2ax n 8x2i5qaal surface is pulled by a 5.0-N force. A 3.0-N2xaxia q52 l482 njaab friction 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, ek8/( /g0 qonpgyz.cbat 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 ifc :r v 9afl-aj;dtif+p-,b:qnitial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the f:c,qfptf-d9 jr;+-iab:lva coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid 9et5roquz).3mwl4p,ou tf gymxi(*, 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 thi5 ymuo,zfe49wp,q gm3tt.)olu( * xre speed of the car when the brakes were applied.

  Two boxes of masses m and 3nz 22r9hq//am0+a;ut6 odxo7 pkk cii m 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 not slide on the more massive box, what is the static fr29/60ixh+mu rzptqi2n/c k a;ak 7 odoiction force on the less massive box?

  Two boxes of masses m and8g mdszqs7* sqlpx27) 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 lesp*sz 7l8s 2)m7qsqxd gs 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 plane 7kzdeyxiu(9z fe:s-rab pj 8t-2 hw -6is inclined at an angle of i-as du9k8: rb2he- wze67z - jfyp(xt$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an5uqn.p2 mpkj-i:ahaa : ru3ttm5;u)v 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 pqo8 +/vmh1ct dqc/ i*5 mgslb2lane 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 iu 8t3rpw8 v4r+rji-eat 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 constant velocb5 frn t)qnm0 zuer,egas68,*ity of agesr8n z5r0 mt*,6 u,qnef)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 slides down a rn,d k 07-12xnx anjnxzough $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass3tw+:oynoohc0lw/(jmi1j v b75x gj7 m 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 50-hti5uh2u 5h /ex3txz0 N along a rough surface. The cable attached to the log makes an xi5teuzh/h 3-x tuh25angle 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 fh wd-a.;xple 9rom rest on a rough inclined plane tilted at an anglehxela 9p;w- d. 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 an inclined planexba.n+r07wey wqbv6 7. The angle of incline is gradually increased until the object begins to slide. The angle v7ry 6a.w0nqbwx7 b+eat which this occurs is q. What is the coefficient of static friction between the object and the plane?