Which of Newton's laws best explains whox/l(gf q kj2 4y9.gt/0qe zviy motorists should buckle-up?

  When you sit on a chair, the fnv g6cct-q.):2.t;pzb v rqkresultant force on you is

  In the absence of an external force, a movingduvuz9utes: .y 9qp mr7,nr .y;3tdsj b8+gw, object will

  When the rocket engine s5rl+0f nkz+zg gx,lq3dik ad7**m0cs on the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, zifgqa ck+dzn,0lkg* m0 d *rlx357+sthe starship will

  A rocket moves through empty space sjpu 0ol2a)-n +4vv 6jaxin*d in a straight line with constant speed. It is far from the gravitational effect of anli-u0ov2 snj+ na)6 x4*avdjpy 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 forel6p ac 6y.w1aal2j0x ward, and you suddenly fall forward. Y paac.e0y16l2j a wx6lou can imply from this that the bus's

  You are standing in a m20n9 b+ lve)wk3adse eoving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate3kl0w ea2 endbvs+9)e stop. What force caused you to fall forward?

  A constant net force acts on an pj f9yp y(zq(az05fa8object. Describe the motion of the object.

  The acceleration of an object is inversely pro,yzhut*ab/ t/ qgwnal(vw;) 5portional to

  A net force F accelerates a mass m with an acceleration a. If the same n2jw8q6v)k;j403lh jdli n7 swu v hv.fet force is appl40i.ufh kv wjhw;j3lq 6)lnv2j78vds ied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What dpuvzw:- jka 8)0cb 2gacceleration results if v-u z bpwk)8a20cjdg:a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon wmk m-.5h3brbyl9 :g-zwkr w0vill fly away. This is a 5-mw:rz0w yh.3-kb km glvbr9n illustration of

  Two cars collide head-on. At every momenk31qtalfd c .-t during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force the second c.dkc1 q3 -tfalar 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 k*5w-8s6ux1 *lmv .g3ngny ur: cedduyou willykgn1 dc xs-*8l6.mdew uurv5n3 :g *u

  Action-reaction forc 7tygd1aa+a-9v3yhn uc/ q.sles

  Action-reaction forces are,)b tlf(cw(d0 lm.b su

  A 20-ton truck collidesocsn(ac,o /ouu9u9 n6hz8a b / with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on the a9o 9uo /counzhu6s8,/n(ac b car

  An object of mass m sits on a flat table. The Earth pulls onr+ds765wcx jj o-n83)rm(n 5vblpylz this object with force m8+ l -wm576p njrjozb 3)y5lnc(rsx vdg, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the c/ vr z7.2lmaeueiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction7rmeu/ l2a.z v force"?

  Your bat hits the ball pitched to you with a 1500-N a( rc v:j swcx0q9d)tx7mj9qhk 6u**z instantaneous force. The ball hits the bat w 9v:)trcmx76szhakx(q dj cq0* *jwu9ith an instantaneous force, whose magnitude is

State Newton's three law 7zna(ijwwkiuu71cr,9n)gh(z lo4 ( rs.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which :fp v jm22 7nfdnt07yoof the following is true about the mass and weight of an astronaut on the Moon's surface,v0mno2y7d:t2 f n 7pfj compared to Earth?

  An example of a force which acts at a dista)o+ywprpd d4,rg u- j7nce is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person jr* -*x.pf8e +la,j jigfb)idweighin8f.bria+jji ,pfx *j*)ldge -g 600 N?

  A stone is thrown straight up. At the top of its path, the net force 9 hnvzxpk 4x yd5*,y-vacting on idvyv45,*knxz xyp9h - t is

  A 20-N weight and a 5.0-N weight are dropped simu7* wgq6, nkxx0fe(prpltaneously from the same height. Ignore air resistance. Com fp( wpex6,0qx n*rkg7pare their accelerations.

  A brick and a feather fall to the earth o8v:g ka9. kezc+ ip9rat their respective terminal velocities. Which object exp pogz9.k+8re ckva9i: eriences the greater force of air friction?

  An object of mass m is hanging by a strino0msl:xyj+9n+luh*lf 3tt(o y f-m* l g from the ceiling of an elevator. The elevator is moving up at constant speedlxt( l:l-o0 mnhy3*sl+9*yoft+jmfu . What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an eleva fclxdm h+ 9u(.acy8noews:5 +tor. The elevator is moving upward, but slowing down. What is the wa s(9u.xce+yl h5f:+mcd no8tension in the string?

  The force that keeps you from slidig foi6rwo1 h6+ng on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest tha4u5ctd:-i y2k r*rsuqn h a5qio 0/xj:n it is to keep pushing it with constant velocit :q0jc4 ktd iru/h in-y5osrx2a*q5: uy, because

  A horizontal force accelerates a box from rest across a horizonabcbhr: r.r0 3kyx90zz+ ;ys wtal 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 tzaywr +xh:93z ;.sbr0 c0bykro the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocifhkfi q13wy+m tj+,u 7ty. Thus we can deduce thatm q yuwfthi,f j7+3+1k

  A block of mass M slides down a frictionless plane inclined at an angle q wi8at8m 6 yeau8pth the horizontaa ym86tu8 ep8al. The 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 wm3aa mits d7*+ith the horizontal. The normal reaction force exerted by the plane on the block is 7dm a3t+ms*a idirected

  A block of mass M slid 3lkv*uczys 3o(np;z ( c8gr-aes down a frictionless plane inclined at an angle q with the horizon nzapg*z3v;8sc l rok3yuc-((tal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined ztug)pe 6 d0 i:er5hz5plane that makes an angle of 30e with the horizontal. Make a statemeethzupz)rd6i5 5 g0: ent which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force ixv2 z,y -xo :mzti5qo,s applied to the object, and it acceleratesx,oyvx,- :ztqoi 25zm at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can o0:n 5iossi dj01z-siaccelerate from rest to 27 m/s in 7.0 s. What is the averag5s1n0oo0d-szij i : ise forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/ncp/u(v5w- 1*r35oynryv r yfo05 gnss in 2.0 s. What is the nw 1v/-0co ynfry5 g *vysnn5o3ur 5(pret force acting on the body?

  An antitank weapon fires a 3.00-kg rocket cs7vt iy 4.,w95ydaks which acquires a speed of 50.0 m/s after tra it d,.9s5wykcay47svveling
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 (p,9*2ani *mh yo tkwpthe same force that you push a 10-kg mass from restmo*hwky,*patpn2( i 9,

  What is the mass of a person who weighs 110lbch:qg-fs8vf 6 2* k g8ymv1aknik25 lb?

  What is the mass of an object tha)2feg -luvun2- h je s+3*pcqvt weighs 250 N on the surface of the Earth where thev2v2ehpng--su3u q*)j+e clf 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 objec9xl**bakytmk u3s knn 16a.4qt on the surface of the Moon where ubm43 kn a6 xntkly*.9k*q sa1the acceleration 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. j+q6z3h0ldl3ol oa-hm.;gvuhfok + 92xxkr 4The Moon's gravity is one sixth of Earth's. Compare thkl3vmj+z3 k x0 l2ufxa4ohroqo-. ; h 6+gldh9e masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of ey8 l:1z*a/;o*5 ruh)k 6brxwxiuhss a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates t *rs: kh 5*x yubliaz 6r18w;)oheuxs/oward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F acts on tm cm,cc;hn7bz g93qj, he stack, and it accelerz mb,n,jq;cm9hc c7g3ates 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 elevat /h )+w vz:dcf5q+gkcior. What will the scale be reading when the5wq zc)d+gk v/ f:+ich elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the -o x03un1x8 7tqx mfngperson is 60.0 kg and the elevator accelerates downward wou78q3x nf x1m tg0xn-ith 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 massowijy13a zcp .: k8.uv of the person is 60.0 kg and the elevator accelera.3 zyp18uc:owivka .jtes 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 h0 :yt (uh0m:9i(vf kldxbf k;ias a magnitude of 8.0 N and is directed due north. Thet0f:fvy:iilk xhu km0(9b;(d 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 flatbed of a truck. b d ll s;6x2:9-qmi*qkbc3mft 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 stoppin ;flst ik623-*cb9mm:bdqxqlg distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a trunb1jmj:h(f s oykp 2)fmnfpn+63b 6 b,ck. 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 forward into the cpbb6n1+fjyh,)3jbn p s(k f mn o6:2mfab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and mzbb1sf.9, l)zok 8fwq = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of theblb ofqs. 9zwzfk ,81) pulley.)

  In the Atwood machine shown in Fig. 4-jf8 (ajmz)ai5/ 5czgphii :4h1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pmh j/i c (8ij4gfz:5hzi)a 5apulley.)

  A student pulls a box of books on a smooth hora -d+ l*/srokrizontal floor with a force of 100 N in a direction/ o srrdl*k+-a 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 78ivovo-mn2 z on a smooth horizontal 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 40.0 kg, what iov2-iv zm8no7 s the normal force on the box?

  A traffic light of weight 100 N is supported by two r+) m(b wa4b3f*hzonm mopes as shown in Fig. 4-2. What are the tensions in*bhomaf+ wz)(mb3 n m4 the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass uajce* 5s/: rav9whp:bnun8+ of the trafficwseuha5cpav+: n *nu : b98jr/ light?

  Two boxes of masses m and 2m are in contact with each other on a friction94 jcaq 7iugneenoe*0txf ,3 -less surface. (See Fig. 4-3.) What is the acceleration of the more *ee4it q,x9nnj- a7fgeu3o 0cmassive box?

  Two boxes of masses m and 2m are in contact w6imqw:g+mwfsq 2 xdoq: ,2kk* 5wthp ;ith each other on a frictionless surface. (See Fig. 4-3.) What is the net force on the 2 x, md*m+pw::tkq qgi5f wwko6; 2qhsmore massive box?

  Two boxes of masses m and 2m are connected 7axtd9 kpof5i+ks. vu(wf2t. by a rope. (See Fig. 4-4.) If the forward for kft ovs +udi97wt5.kx.p(f2ace on the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. 1 b 3(nfupt;zh(See Fig. 4-4.) If the forward force on the more massive box is F, what is the u t3f;zbp(n1hacceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fig. 4-5. : 7 jok(7bghdk Box I ohbo kgkj7d7: (f 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 g8oi23rxh6j gbox and a desk are 0.40 and 0.3 8gxjho3 ig6r20, 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 on wcn4))zpri g*cm+nhrh0nf -8x ood are 0.50 and 0.40,8*nip-g+ ) rhrfm4)znnch xc0
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 avqg6il/xq*6cs+ a;ve*t)hxyq .kg 3t stop with a constant accex6 lghq). 6es t/vyv+3ait**gqq c; kxleration of -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting o5r(sfrh.,, lsfjl69, v oqih hn a horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the moti,., rsv oi59h lrshj6fhflq(,on. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at 46 prd9v dxn:bz r3vxws2,j e,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 50x6yr12p v 3lall+ax: e m on the ice before it stops. What is the coefficiene1 2 ar l+36:lxalyvpxt of kinetic friction between the puck and the ice?

  During the investigation of a traffic accidek1i 6s rc8ve mp:o:;asnt, police find skid marks 90.0 m long. They determine the cro:em:6 v aipssk8 1;coefficient 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 an0 . i.d6ol-p2wak/+javpfg ycd 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, what is the static friction force on the l 0p6k ai 2j.vfod gy-pcla+/w.ess massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surf+v. oxgxy)juu jte3/; wy zg*t7gu q,ey/m j16ace between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less massivtmgqg +ujex/7g31oy. w, t*6j x vjzy/u)eu;ye 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 in*o.f.;buw1yj ksh(+ dwi/ j 6 bouv1ole4ra q2clined plane. The plane is inclined at an angle .s y6ovlif.k1 d2 *uao+/ q oj1jrw(ue b4;hbwof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill thaffbcrvro0+ ,;t 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 anglvr9 6idl5+ gi)qqnd-xe 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 ti s- zl81 rg/p9dp6tpgmlted 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 co+ufp(0otblr3 nstant velocity of 6.0 m/s lb o3rput(f+0.
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 *:-buo rh1u dza 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 downexnf haph5a vfa2-7 41 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 81r 7qjt(z:hjc g3hjs500 N along a rough surface. The cable attached to the log makes an an1hj8( zrjjt7 sh 3qg:cgle 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 :c2qc dxv0c/egc o 7j c3:gke8inclined plane tilted at an angleeccjc2qk3o c/ eggvxd : 07:c8 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 plane. The angle of bb4b*i d-8ejy incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static frb- ej8b 4*iybdiction between the object and the plane?