Which of Newton's laws best explains why motorists z8lhugslw 1tbl0 *v- : fxs7a6should buckle-up?

  When you sit on a chair, the resultant odwm 6f5f8vt4 force on you is

  In the absence of an external force, a movshvhsi)7xd* +q:j +q4r jof ,ling object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned w 1m+x5 *iiboxoff, while traveling in empty space, the starship wiw5+mb ix1io* xll

  A rocket moves through empty space in a straight line with constant speed. I/axp:0d--n uj*bwc7 zq4vxpgt is far frou p/d-:47bv- pzax*jg w0xqncm 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 forward, and you su/g;uckmtfy4;;wxy:1w m4) xb3dnnnlddenly fall forward. You can imply from this tham xwn: 4 c y/m;gn;3btxkw4) f;l1nydut the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall f9 ,-usoukd 8lborward as the bus comes to an immediu9ok ,ld8bs -uate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe mc gak )6k wemn0rw3 50fhz3b6/ii wy:the motion of the object.

  The acceleration of an ob+tzug wtqb98pt2xg 1faez :.w f m616zject is inversely proportional to

  A net force F accelerates gxq n.e10,ek)tse.a la mass m with an acceleration a. If the same net force is applied to mass 2m, then tn.)k tx g lq0e,1sa.eehe acceleration will be

  A net force F acts on a mass m and produces an acceleration2uv0i x ku 7+xgl5lc5i a. What acceleration results if a net force 2F acts on057 c+uv igl2klxx5iu mass 4m?

  If you blow up a balloon, and then releasjke- -6jrfv;dhy cl31 e it, the balloon will fly away. This is an illustration13v 6--fkl; jcjryhed of

  Two cars collide head-on. At every moment during the clh a05/tyl47b os ihg)ollision, the magnitude of the force the first car exerts on the second is exactly equal to the magni5oi 4h0h/ y7l)tlbagstude 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 n(slqv8: etqd151 aoj which the object exerts on you willq:s1 oeq 8n(lt1a5jv d

  Action-reaction forcej 2jsriu 2b,yezt e*z.5m;rk8s

  Action-reaction forces a qp 6hf:uw8ovwo )5j1rre

  A 20-ton truck collides with a 1500-lb car and. :8. fdmypw)lge+sx7 0izqud causes a lot of damage to the car. Since a lot of damages.d ) dm7wfe quy0g iz8:xp.l+ is done on the car

  An object of mass m sits on a flat table.glzk:*gfxt5 +l.sj j6 The Earth pulls on this object with force mg, which we will call the action force. What is the rg+zx:s5 l.ltfj j6* kgeaction force?

  A child's toy is suspended from the ceiling by means of a string. The Eaeoer2rnvymt6+4*obcg+ ) 5x qrth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction force" t b6r5+*)orqvxe4+2oy nmceg ?

  Your bat hits the ball pitched to you with a 1500-N inz ow8(n 8g*)(vtw3e wgd*dn85fk sgyw stantaneous force. The ball hits the bat with an instantaneouseg(kgsw*wdd()8gwvwntno 58 *y38z f force, whose magnitude is

State Newton's three l2 x2oxb;upgz cw.:xn3aws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than qp 1chqvkqa9jfg;(.6 on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to E9gf(c 1 aqjh6qq; k.vparth?

  An example of a force which a2zvx ye+1aipu(0gyy ;cts at a distance is

  Who has a greater weight to massvj: qf pdlv v0ax;44ha3dw i yj*(z;3l ratio, a person weighing 400 N or a person weighi 4lvhj fxd(v0 iadawp34;z:qvy3l;*jng 600 N?

  A stone is thrown straight up. At the top of its path, the net forcyhhwld,w )uo8y2s (5 3acl3jp e acting on it 5l 2 y opl38ads3wwcyhu ,j)h(is

  A 20-N weight and a 5.0-N weight are dropped simult+h()2vfj iwt-xcn nk+ aneously from the same height. Ignore air rei2k )h-njftn(+v c+xw sistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective termi ,f5ex7v1/qn g9 wuhhfnal velocities. Which object experiences thg h5u1 7w/en9 q,ffvxhe greater force of air friction?

  An object of mass m iuii;op+5ya2kz) (, pevbeya7 s hanging by a string from the ceiling of an elevator. The elevator is moving up at a(z5, pep i uoyykbv72+;a ei)constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of 7rs. arro7esn.m, 8hfan elevator. The el ron. 78s.7ermh asr,fevator is moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding e*kecd+5b:et sxcv;)l 5fn3z on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is b9g.s l1w :i rn:-df r:twbmt3to keep pushing fnrg:bw3md lbi :ttr:.9- s1wit with constant velocity, because

  A horizontal force accelerates a bo0fc5 x1vdp tn0ag 6fy1*n 5yngx 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 horizontal force is doubled. What happens to the box's accela n*fxn gtf10 0y1cgn56y v5dperation?

  A packing crate slides down an inclined ramp at cono452 -k zm.eicdyfzy2stant velocity. Thus we can deduce2eydfko54cizyz 2- .m that

  A block of mass M slides /,pyo fi) uzsn5p px)+yrq.m+ down a frictionless plane inclined at an angle q with the horpfz )y+roiyup5msxp.,q )n / +izontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at cp,dw9.* z vgnan angle q with the horizontal. The normal reaction force exerte*gp9 wz,c ndv.d by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q wita45g-i lfdjo(81 kh+nz t :vdeh the hon fdei+481ohtvk:jdgzla 5- (rizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclizjen7ct0(jdc whoq6598to nu5/2kb v ned plane that makes an angle of 30e with the horizontal. Make a 08tbk/5ujt2 e(cv6hn dzoj9qw n o5c7 statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to the objecoqw a,rxej)h.3 c0yt ; gwpa+f;zji(3t, and it a;oejzywa0g(3 c)hwxtrja;.f, pi q +3ccelerates 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/9 rcufop. ut,.s in 7.0 s. What is cur f9t u.op.,the average forward force on the car?

  Starting from rest, a 4.0-kg body ds/ t*c)po kgjfcf2,3 reaches a speed of 8.0 m/s in 2.0 s. What is tp, f)jk/ofd 3c*s2cgthe net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a ss2 k:q6j-(p jzxhwx 7mpeed of 50.0 m/s after traveli2w-p7jq :(m jhsxk 6xzng
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 sa 4fjdyr( 9j9r*owhis04usf 3bme force that you push a 10-kg mass from resf yrws30 9 bio ujhd(fr49*s4jt,

  What is the mass of a person who wei5cx)kb hn9l1 0dm:rygghs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Eartfrn4arh *9tgh.*( c oth where the acceleration due n .(9f*rh t*o ca4trhgto gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the itojbt2 5:yy3 mass of the object on the surface of the Moon where the acceleri:b3yoj 2ytt 5ation due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. The Mi n3, mat/hjimtj 8d0omd *7pq +ko+v8oon's gravity is one sixth j3ddo8oj8 ,ttpai kn/h mq *+7mi0v+ mof Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling 9dy6udk9( a ry.wwf5oq1izh1 on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. o 6qzihr.wkya15dwf(9y91u d What 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. A forcoikwd-w lck6z ,f8-m ,e F acts on the stack, fk8diwolz- m ,,wc6-kand 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. Wha,z* 1 nfqks s2rjnao-3t will the scale be reading when nq n2s okj,*3rfs1az-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.2k2emw+ djobw1jv8j i a.2yp is 60.0 kg and the2+mjpkjv w.22b.1 wa ide 8joy elevator accelerates downward 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 the3 ia.aqp2lx5m)(sdw g person is 60.0 kg and the elevator accelera2(5qpa wlmsd ai 3.)gxtes upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a ; lbugqrxr016 yxae*:5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The sec 1r; u:xlqare06ybg x*ond 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 truckal uxvo/oa y1.rl, 1l8. 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 vool1aylurx/a, 81. lis 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 o t+ tk+7dm5b4 rk/dkj f5tye/af a truck. It is held in place by metal brackets that can exert a maximud/45+army/ +kedt j7ftk kbt5m 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 anuflg hm 9ext/yz5j03-+5 zuwkdvhh- )d m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore frictio5ehyg3-wh0h 9 mxld kuz-/v5+jfzu t)n and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1-w,-u erv4sbq , if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? ( u,v-w e4bsrq-Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a sm )2h*turxiz-: .,)sjjmij jzgooth horizontal floor with a force of 100 N in a directions ir,2)j: ) j.-tmuzzxgihjj* 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 a*h5d98 .n xc, rt/ rrpmgya1dj2dd- mhorizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 4r g-1*cd 89p.hnja5dd /a xtd2mr m,ry0.0 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. 4-0)ar 3q1z:z* f5bpyawze *b bu2. What are t* q)1z0yeua:bbw fpz z*abr35he tensions in the ropes?

  In Fig. 4-2, if the tensions in the r hlk+.c6og f,,0zy fgmopes are 50 N, what is the mass of the traffic light+kfcl, 0ym,zhg6g . of?

  Two boxes of masses m and 2m are in contact with each on46zwzj3znu8x/ t7wrr x6;z gther on a frictionless surface. (See Fig. w6 rgtzjnx7w /36nr8zxzuz;44-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and ats1zwv2o7a 02m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the morea1o7aw0 2tv zs massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the f91lg7 hblrcjt :tdj 2:hoyb- 7orward force on the more massive boxbtdhboh r1cjg2l - 7:9tj:7yl is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are conneqk9kt2f;elr 2dnq.p +cted by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the accele.kt2l9+ dqp;eqfn k2r ration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fig.hcxmtel+ r-a holkp b9,3g418 4-5. Box I of hlm3,4pgcahke 8+b-tlo 9 x1rmass
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 kgx0y;hlc6-,nve hn0 0 z -slkrinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the bor0h-ecn0hlvyx l s0kg - ,z;n6x when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50w k13d* ri + : ggspnlbtik(2p1(0hfzo and 0.40,gpkg :ipi nk+rt 1l b*f0wh((z1sd3o2
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 comes to adl2;ys*zn 8+kkpqs :m aw 8c,tad tmsq8zwsk2k8 ;l,pc+y :*n stop 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 horizontal subs68 rl 9uvdnxf(x*u(rface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is th9ul nxv*d6(8(x ubrsfe acceleration of the object?

  A horizontal force of rg )tm 96nl01u gstxg;5.0 N accelerates a 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 gamexhs(uqbt4o sh-3; aj,b 4p s5h, a puck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kis4sbq; hh b(t53sj o-xp4hau ,netic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 90.0 mcek(bwf tzks1zo-af s3mw 6 -0.:kl9a long. They determine the coefficient of friction between the car's tires and the roadway to be 0ksa( ksl mbcte:169f3w 0kwa fz- .zo-.500 for the prevailing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses mp4 8-ccg1bjuh and 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 not slide on the more massive box, whap 41bj8 gc-cuht is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surf pf z(6mf *4zmzi1ck:face 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 nczifk f4m6*zpm: (f1zot 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 is inclinb f75r9m0za2ugqojr 9 ppm ovvc/51x7ed at an angle 977umrvmp5 f z1 /pq 9xcbg0oaj2rov5of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle of y8 bu uky)wao 6one/;9$10^{\circ}$ 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 angle of gc+++ws te)7sqfw8c f9jw a+ l$37^{\circ}$ 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 o8f mm;yc,cxwfurd ek 0d39j1. f $35^{\circ}$ 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 velovjo 2;fv5 lrd*city ofvf *r; 5vldoj2 6.0 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 masqx o .6p(linq5oa b9;ds m slides 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 rm d vqw; k /4wcfw3*,wt2fwy/uough $37^{\circ}$ 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 attache q(ajxd(p,h 7b/t,ppxd to the loj pqtp(p,h( adb7/ xx,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 rest on a rough inclined plane tiltedwzpmslvkp+9dn +h) crosdi)+ + 2q,4l at an angle of+ 9low,nvhli)ssp4k2d+) q r pc+z+ md $33.5^{\circ}$ 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 plane. The angle of incline 2ajvusqoe+a a.rvsy4 p(02s 5is gradually increased until the object begins to slide. The angle at which this occurs is q. What is thserjys .4sqo u02+( 5 apva2ave coefficient of static friction between the object and the plane?