Which of Newton's laws best explains p40drtpl2o 3fbs2.gkwhy motorists should buckle-up?

  When you sit on a ch y2dz 9 lo4r,z7dd4ytyair, the resultant force on you is

  In the absence of an externaletswkz1 ;p d6kt3lk2 1 force, a moving object will

  When the rocket engines on the starship N4lkj -b skvq38O-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the s- 4q 83ljvkkbstarship will

  A rocket moves through empty space in adfn1h.bdxk ,g.x2x w:i. e5sg straight line with 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 m h5sxg.., 1xeg b.idf:2xknwd otion is

  You are standing in a moving bus, facing forms ryl3b+ r.an(8/ s* .sjllzmward, and you suddenly fall forward. You can imply from this ths/.s m*8ms jnly barrl+(3lz.at the bus's

  You are standing in a moving bus, facing forwaod6 xa1(jcb(z) o ijr i::u(yard, and you suddenly fall forward as the bus comes to an immediate stop. What force caused you to fall1a ij:( (au6o(d rz)yo icb:xj forward?

  A constant net force acts on an objw1y0wy 5yo tj(o(don9 ect. Describe the motion of the object.

  The acceleration of an ob,0ibgfea0en) ject is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If thedk3jj9 vqwkudj 3.iry.:a /3r same net force is applied to mass 2m, then the acceleration will bjdyk rj r.9/ d3ukw.qij33va:e

  A net force F acts onzf5si gu+4:0ige- zr r a mass m and produces an acceleration a. What acceleration results if a net force 2F acts on 4u gzrzre i+f50s i:g-mass 4m?

  If you blow up a balloon, and then release it, the balloon wil- 4 osepd cfr7-k ir3mq 5/bn(u4.vvc;s poey*l fly away. This is an illustration ofe4-r7c.c-iprs uk5*oo b mdf 3(;nv4/p eyvsq

  Two cars collide head-on. At every moment during the kvk0s+/ ksv +zohc c0(q 07fm*bdoqz +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 tv0qbczzoqk+kk7vh/ * +m0 0d+sf (coshe first. This is an example of

  If you exert a force F on an object, theq8yp:- r8)l7n tcveaw force which the object exerts on you wilwe8:cp nvtr7 yl)q8- al

  Action-reaction force;k:+ph hgx din7zv2t a) fm*1as

  Action-reaction forces3z s1icdps0)y are

  A 20-ton truck collides with a 1500-lb car and causeshls h:1prgs n/jz.y : ec6as09ip2lq7 a lot of damage to the car. Since a lot of damage is done on the :ghsp/:sl.pza i c0h2y7s1nl9re 6qj car

  An object of mass m sits on a flat table. The Earth pulls on this oba d 5arkju,(oxt 3ij.*ject with force mg, which we will call the action force. What i. ,ja5xrk(iu adj 3ot*s the reaction force?

  A child's toy is suspended from the ceiling by means of a string. Thdl 56is;gdtb :e Earth pulls downward on the toy with its weight force of 8.0 N. If this is the d6b5g :tid sl;"action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N insta-tspi: 0 pjx aqoqv5o2:9sm-fntaneous force. The ball hits the bat with an instantaneous forfpt-x ojam0qq-ps i:52o9:v sce, whose magnitude is

State Newton's three laq,z.t dw4dv/kyuh1) dws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than opw/*)7j f 9pfipcbu hzxk4 57tn Earth. Which of the following is true about the mass and weight of an astronaut on th5k)9hpt 7p fwju7ipc4b *zfx/e Moon's surface, compared to Earth?

  An example of a force which acts at asom)in)bmq1oz0k 9e. distance is

  Who has a greater weight to mass ratio, a person weighing 400 N l -au-ay r-d(kor a person weighing(ya r-ul--d ka 600 N?

  A stone is thrown straight up. At the top of its path, the net forcef;x hnjsh9u* lb:jmz 65*qg: d acting on it b;:uh g9n:x6jq* j 5dl *hsfmzis

  A 20-N weight and a 5.0-N weight are dropped simul-1t50 n linaw-l,i40k0g xrotu/wr cutaneously from the same height. Ignore air reulg4 0 5ori0wt-1/ lxcwk,0tiua nr-nsistance. Compare their accelerations.

  A brick and a feather fall to the eaj ob1l:g8vot.js6deczb9 ; -a rth at their respective terminal velocities. Which object ex:jts.o;do 1c86- lejabz9v gb periences the greater force of air friction?

  An object of mass m is hanging by a string from the cez0jec,p4o/au4 e9gr c iling of an elevator. The eleva4c/epo90ag e 4c,zrujtor is moving up at constant speed. What is the tension in the string?

  An object of mass m p.0zlpl7mjz uyqg;,+is hanging by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. Whq;p,y0 +uzglzj7l. mpat is the tension in the string?

  The force that keeps you from sliding own8.x, ntp.sv-v4y817nkz 0ottrp zs n an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to keep u -:n7gq3kf+i 0ygr dbz)ms(x pussn7 :gy i)3-0fxz+qkurgbm(dhing it with constant velocity, because

  A horizontal force accelerates ahlp3 zr,bpnvw6i 0w6bo;t 0s) 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 horizontal force is doubled. What happens to the s,6nzbv ww060b rl p)3ip th;obox's acceleration?

  A packing crate slides down an inclined ramx cgmpdngp-a b-2 x -l)d(q-mu(kxq1 *p at constant velocity. Thus we can dednx lx gp2-k*xq- mgq d( du-bma1(-p)cuce that

  A block of mass M slides down a frictionless plane inclitcmpd.i)h.58 * ssh h3rjq4ouned at an angle q with the horizontal. Theudos84cipsm *) t.5. jhr3hq h normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q wbh:ou) ,y qt9vgp9c r.bi) k(vxo(:hpith the horizontal. The normal reaction force exerted by the planeb9 . )(k 9(orthvbu:)pgiyqcvpho: ,x on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angl5 h-d ndmftk7-e q with the horizontal. The gravitational forct5mh dd- n-kf7e is directed

  Two toy cars (16 kg anya u)d0x,yw,j d 2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the x,, uywad)0j yhorizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionlejcb:dn4(z e vjv;:k- wx3vsd( ss surface. A 16-N force is applied to the object, and it accel jcde: x jnwvvzs3d(:4;-( kbverates at $2.0m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accel9gqgv))9cwpdm /xf2bq)v2 g ferate from rest to 27 m/s in 7.0 s. What is the average forward force on the car?dm2)bg2w cvv/pg qqx g)9)f9f

  Starting from rest, a 4.0-kg body reaches a spygw e 7x;19xoteed of 8.0 m/s in 2.0 s. What is the net force acting ty9;owgex 7 x1on the body?

  An antitank weapon fires a 3.00-kg rocket which af 8d*wj0 wi2-6dk*wr gl,obapcquires a speed of 50.0 m/s after travelin0, ofdibr* k g-2l*pd8wwjaw 6g
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 force that you push a 10-kg massugkf/g;e7wkb,m ( dr4 from rermwdeg/g(fb ;k4 k, u7st,

  What is the mass of a pe ydu boy6 l82rk yu+rphk0pokpah/*e*9y1b4* rson who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surfacx +kiaydu,98 ce of the Earth where the acceleration due to ikad 8xyu ,9+cgravity is $9.80m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the objf.q;n ltf2k)nect on the surface of the Moon where the acceleration due to gravity is only 1/6 of thafk nl.;nt2 q)ft on the Earth?

  Object A weighs 40 N on Earth, and object B weiqwnrcqfh- (0m4cm sq:v+ utrm 9a6+ s7en18o zghs 40 N on the Moon. The Moon's gravity is one si0mu qcr at479q8v+onnms+q-zcwr h61:(mf esxth of Earth's. Compare the masses of the objects.

  Sue and Sean are having 5*c7kpqt2e 3 ppx )dkla tug-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 the roqp el32*)ck7xp d 5pktpe accelerates toward Sue at $2.0m/s^2$?

  A stack of books rests on a level frictionless surface. A forceb8w v7y79 g zhpu:qkl6 F acts on the stac6:lvp w7gqyhb zku897 k, and it accelerates at $3.0m/s^2$. A 1.0 kg book is then added to the stack. The same force is applied, and now the stack accelerates at $2.0m/s^2$. What was the mass of the original stack?

  A person of weight 480 N stands on a scale in an elevator. What will th7/2w ghhn;sp py, unn:e scale be reading when the n;n72n:p, g w/hshpyuelevator is accelerating downward at $4.00m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.pl0,fb ngjsq) 7nt(:f0 kg and the elevator accelerates downward with an acnfjsn :0bf 7g, lqp)t(celeration of $4.90m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If the mass9qqi4m h4iqb: of the person is 60.0 kg and the elevatoq:qiq4b im4h 9r accelerates upward with an acceleration of $4.90m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg ma qp52k.1bib eujwmo ((ss. One force has a magnitude of 8.0 N and is directed due north. The second foroi. 25b(qu1 b pkj(ewmce toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg+1 l/my nhh)pkoex53b rests on the flatbed of a truck. It is held in place by metal brackets thaoy5n1+x / )lph mkbhe3t 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 rests on l5zr *8rnqe53fwuhyi :kv6x /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 stopping time if the load is not to slide for/qf3y e:uwv5z8 rnli*r6 5xkhward into the cab?

  In the Atwood machine shown in Fig. 4 ++ibhz-chd6p -1, if M = 0.60 kg and m = 0.40 kg, what is th -z+hdp+hi b6ce magnitude of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M -lax7xgt c14:znh5h t9izwz 0 = 0.60 kg and m = 0.40 kg, what is the tension in thez 90ai17wzl5zgx4- thtn hcx: string? (Ignore friction and the mass of the pulley.)

  A student pulls a bo o02tgx qu,s,gx of books on a smooth horizontal floor with a force of 100 N into0 ,g2squg,x a direction 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 / nwxyv0x/q.7uxd2ew 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 normal q wwun/d2x. xxv/ey7 0force on the box?

  A traffic light of weight 100 N is supported by two ropes as shown in3r,jzto9v- cxa s5a z) Fig. 4-2. What are the tensions in tz xa)cso v5r az93,j-the ropes?

  In Fig. 4-2, if the tensions in the ropes epua(;b(blbkz:* cyr2j5 iz 3gf+ar -are 50 N, what is the mass of the traffic liie(*g+ a cr:ku;p(5b3 a2lyjf zrb-bzght?

  Two boxes of masses m ann. e w-j0e21r/vs.zlr x: frnkd 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the eswx r2/-nvf1.rl.rkej: 0zn acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionless su4ol, 3t )ej 9 1e0avxl1nylfcurface. (See Fig. 4-3.) What is the net force ly90nu cj oea1etx4f l1l,)v3on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fiwi0bn o3;c(x j0.:fzvp ei1u 8j q1csxg. 4-4.) If the forward force on the more massive box is F, what is the tensic.s:xjj(i131 f8i qx0ocevz puw;n 0bon in the connecting rope?

  Two boxes of masses m and 2mok/bs-ah 7j f:3vo2rd are connected 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 massif7bo v3h ska/ j2d:o-rve box?

Two boxes are connected by a c3ptjvv2 l7( (i7ac yzrt-k 2maord running over a pulley as shown in Fig. 4-5. Box I i-atl7mvk r2v7(a(z 3tpcjy2 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-kg box and a dgn3ulb8ux6 t 0+apk, kesk are 0.4au+ kx6tgnl , 8ub03kp0 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic xf tg5 ub 2p1)w77;,uh-.ne vicualo mon wood are 0.50 and ue2f5x7)v ,1w.iloph g btau7 u-c;nm 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 +xs w)8rhk91n y: yjt3 xuiyrrfi)o))b1 direction. It slows and comes to a stop with a constanthi)s8 x1btfr:wrjoiy3urn)y 9ky )1) acceleration of -$2.45m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surface is+ h5f ub-k dwz;a4pvr. pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of the object?5 vwzaf+pk 4bu d-r.;h

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from reaq9 :u igsan0d- iupvvns 5hg-43d)/ vst, at a rate of $0.50m/s^2$ 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 slidex- 57g8ldg- cpy 6uv/wkllc.es 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and the i l6gw g5-ep lyc/ .dxclu7k8v-ce?

  During the investigation of a traffic accid:b it k79-rruoz .4ae3je ul4vent, 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 prevaik- e4v 7:3ezrtua ri4l.9obu jling conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The suhy7,r 9rjhqe,rface between the more massive box and the horizontal surface is smooth and the surface betw,rh9 r,h7 jeyqeen 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 and 3m u2r,u:bx8 kufare 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 coefficient of static frict buu8kxrfu:2, ion between the boxes?

  An object is on a frictionless inclined plane.jue2 v8 i0ebnvy(l3/m kz p63u The plane is inclined at an anglevnpjbv3 uy 0/z62u kl eime(83 of ${30}^{\circ }$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill*k+0 yw89nm bs, gc8gxrftm9x 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 witfxlkody9w t3ys*,4m j0o, dj k(2yx n4h 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 inclin0iq+ p)g;xzuwahv25 jz*3oa w ed 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 cons2hf dc2z(sau jm 2e/b9tant velocity of 6.0 m/s.h2z 2bs eum/ad2jfc( 9
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 rougx4 mr kpn7mo*y,spf(rt 9n 1m/h ${37}^{\circ }$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m j/63ak(g5 twcawe2z f 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 wep4-l/:d zph8p esgt 6nighing 500 N along a rough surface. The cable attached to the log makes an anglee:46/8p gt-znplhs dp 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 ro5pp h,za8hes 6zjuuxy6/qru v t7n 8,+ugh inclined plane tilted at an angle of y t6v5 phzuheqnu78sr /6z8jxau+ ,p,${33.5}^{\circ }$ 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 angl3 wb:2h x3jt vke*+kkxe 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 jt 3bkh3vexw2+* kxk:the plane?