Which of Newton's laws bes,0m n1x, z qp-ynzng/zt explains why motorists should buckle-up?

  When you sit on a chair, the resultant forepsum 560wv 8eg;fa7yf. m)y) erinz-ce on you is

  In the absence of an external force, a moving ob :jg9r vmac09nject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are sudd2e ke .l/ u*vv(qy2jexenly turned off, while travexlu2 .qek/2e*e( jvvy ling in empty space, the starship will

  A rocket moves through empty spllqy/6i;r0iak a, t(zace in a straight line with constant speed. It is far from the graviq l(0ilr6i; ,z/aytkatational 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 vw/ikunv/- g 6you suddenly fall forward. kiv/-gv6 /nuwYou can imply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall forward odn70fr fr sg0)0g9xzas the bus comes to an immediate stop. What force caused gffr 00gs xonz07)9 rdyou to fall forward?

  A constant net force acts on an object. Describe the motiopt eggfry :6s hl-a+ l:/tqp:9 g8u+wvn of the object.

  The acceleration of an object is inversely propor.3v k1dibwwrai mx704tional to

  A net force F accelerates a mass m with an acceleration a. If the sy)qg4vmr 2 *+wv :8 qswvvr i5aql:o6tame net forceym :q)svwgv:8 q4r*aoi2lv6wq5 t+v r is applied to mass 2m, then the acceleration will be

  A net force F acts on a qgy)-p1uezh ay80ty5, .y xgy mass m and produces an acceleration a. What acceleration - u08,xyazq.) h g tgyypy51yeresults if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the 5 7mnzmo4d)n+8 g xio+9.lys5 ix.zpkh9 xafx balloon will fly away. This is an illusk7z 9loho+.dz y 4m5sa)pm gnx9if5 xxix 8.n+tration of

  Two cars collide head-on. At every momento allxa -.+vwtb8 k*5ynhjg*tdps*2pyq2: a7 during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude* 2k82da xgq:*v *s.hjbolp7 ty-tyalw n+5pa 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 /e cdi;pz, 9u/4x.x6a1kx*ra fg its d co*(ncwhich the object exerts on you wil (.a/xn/ixdt, uzg*dp c*4si9roc ;afcek 1x6 l

  Action-reaction forcedv tvzl5 cr4;k*l(0pss

  Action-reaction forces jw4a )c oc6e,/4yjt* c3g au iju1*rbzare

  A 20-ton truck collides with a 1500-lro55 zk- kl ;ugfm9qnwmi8j7,b car and causes a lot of damage to the car. Since a79zifklg -o,m85n mqj ;w r5ku lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this object with fjd vq -/ hrh*2p+hnfd,gny (m;orce mg, which we will call the action force. What is t *p(fh-y,qh/2+ d;dhgnm vnjrhe reaction force?

  A child's toy is suspended from the ceiling by means of a si95j9dkszy (o/ *xioutring. The Earth pulls downward on the toy (idy 5xjz 9k9/o*u siowith its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched4 .lovukl2s34aedj +den ; vq9)ipci4 to you with a 1500-N instantaneous force. The ball e;2i 43 eunl4 o .ad vcpqis4j+9dk)lvhits the bat with an instantaneous force, whose magnitude is

State Newton's three law/ be3bggta0+bs.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earhdqk36vldkt5if v 00( dl+nu3 th. Which of the following is true about the mass and weigfhd3( nk 5uq0tvk0 6 liv3d+ldht of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which aco5*1iv+bnewydga9 u3 1)mgtmts at a distance is

  Who has a greater weight to mass ratio, a pezi8f,: iab: merson weighing 400 N or a person weighi8:ia:ez i fb,mng 600 N?

  A stone is thrown straight up. At the top of its path, the net for4y56 +qrh)p. vr6dzwd f*mkyjce acting on it is6w6 +kf4jdyy h *rmv). 5qrdzp

  A 20-N weight and a rmmr+dn,9h1w/ ,/rr ghs( wuy 5.0-N weight are dropped simultaneously from the same height. Ignore air resistah/s wn mrrru 9/g,+wy( 1hmrd,nce. Compare their accelerations.

  A brick and a feather fall to the earth at their respective termi6 4ul8nqgur9tn4rv6t:dhhy- nal velocities. Whic4 g66rd-qtt84 rynn:v9ulhuh h object experiences the greater force of air friction?

  An object of mass m is hanging gcdvt0/5j-exue 9/tiby a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tensioni9e dtxe0/ tu/-5gvcj in the string?

  An object of mass m is ha;dfcrcxv j tsr9;4ucwq)8bmo ; -90grnging by a string from the ceiling of an elevator. The elevator is moving upwar;8xm4uco9d-q rj 9c)srf;brwc v;t g0 d, but slowing down. What is the tension in the string?

  The force that keeps you from sliding p kf5wqh2vd/,ganqa:2y f53x on an icy sidewalk is

  It's more difficult to start moving a heavy cabv-8zop,k/y2 thja-u rton from rest than it is to keep pushing it with constant 8-tua,/j 2 ko-pzy bhvvelocity, because

  A horizontal force accelerates a box from rest w1/0yk,jw6(zht aebf across a horizontal surface (friction is prese,zw/y(6j0t he b1wkafnt) 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 acceleration?

  A packing crate slides down an inclined ramp at con7/x z3*b wuengstant velocity. Thus we can deduce thabe/3wguzn* 7x t

  A block of mass M slides down a frictionles56ywt f0n1m4ge mm5y n3t7y nqs plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the b4m 0nm61w n qt5 netgy7fmy35ylock is

  A block of mass M slides down a frictionless plan ,qhdgfml2zzdz 0 : g64jpf6f0e inclined at an angle q with the horizontal. The normal reaction2f6gd,d6 zmf phqz:gj400zl f force exerted by the plane on the block is directed

  A block of mass M slides down a frictiob3rw)ni g1opia 3 ,mb--gfpb ;nless plane inclined at an angle q with the 3g ;bw1gp-p3bbf)ma,o i nir- horizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are rel)xiku/wp )x e)41y qr:yp)ci pce/qw)eased simultaneously on an inclined plane that makes an angle of 30e wit)ux:w)q)cp /kp 4w )qy/pi)re1yeci xh 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 *ei ttd* -e f*t-thzq9n1luj4applied to the object, andh te1*49e*q- t*-fzilnj d ttu 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 rest8zk6p6 kd xp6 na,nsk/q7q*h f to 27 m/s in 7.0 s. What is the average7q n/hzk86k6psdk*anq pf6,x forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. Wha0:v g oudul3(yt is the nedu( : 03lvgyuot force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m/g8hte;7g/8kq :j xkzg s after travelx/7:j8hg ek8zgtk gq ;ing
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 f;+5 7i395uy )wsewf0hq wff oo(zc zucorce that you push a 10-kg mass from rest,ho qwcofu(w5f su+cf5yz37wze9);i 0

  What is the mass of a person who w 8tk3txggx*7beighs 110 lb?

  What is the mass of an object that weighs i+s(. wmt5;abb3 gvnk 250 N on the surface of the Earth where5+ ; istab(vw3.bkng m the 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 object ondn1-,8p-x17 47t ve0wldisp*doweqwzua* k w the surface of the Moon where the acceleration due to gravity is only 1/6 of that on the 1 zw8ld d4oaw-x-0nq pvek*esi,p7w1*w7td uEarth?

  Object A weighs 40 N on E ge3 /yqj 89xl7(l m4givhn/n7rfpyl1arth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the /p qm fjr8y(3 g1g9l7i/4y ne7llhnx vmasses of the objects.

  Sue and Sean are having a j(on+2heowflp k/ .2v )jk f9otug-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 rope accelera w j2.h)k(oo+pfnjle/ 9 2fkovtes toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F actsn 1(5v:mfog6z7l fxcnr b. g7s on the stack, and it accelerates f67 7vlmo1.cg sz :fg(nbnx r5at $3.0 \; m/s^2$. 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 elxulh+nvqk0 6i8. uv ; 6ojwb:ievator. What will the scale be reading when the elevnl i.wuq + ivbo0 k6xhv8u:6j;ator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator.z.oe88r;1jp /yhu s xb If the mass of the person is 60.0 kg and the elevator accelerates downward with an acceler;.p j1ye bzroh 8u8x/sation of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. Ifhg3r3xol b(3g5f:u k c)iq/tu the mass of the person is 60.0 kg and the elevator accelerates upward with an l3c3 gi:o/ qg5uf3hrk t)xb (uacceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. ip;5j n odv hf ap-nwx6-)ky c/52y+waOne force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?awd p6;pva)o-5/fnki+ j2n -ch5y yx w

  An object of mass 6000 kg rests on the flatbed of a truck. It is held ib:nyypmg rp :s,3 f/s8n place by metal brackets that can exert a maximum s:n/s :,83pm prgfy ybhorizontal 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 the flatbed of a truck. It is he+d(qpuqq 5mag;/ m6 rrml js)9ld 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 ti r s+6uqljpdrq 9ag;/)(5 qmmmme 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, +f- k70: .nwmd 0lxheyhf,burwhat is the magnitude of the acceleration of the system? (Ignoru7f e0r . 0,hwy- dlm+fnxh:kbe friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if + +xyuvn;uaptn7y7 p) M = 0.60 kg and m = 0.40 kg, what is the tension in th +yt+p7;ayuvn7)n xu pe string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor winr)fy5 )olg-rh+kp 7r th a force of 100 N inp5n )g-r hf)yrlro7k + 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 hoe 7rj a;9mb2frrizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the b r9fe2jb7r; maooks 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-k*aslkkt8 w 3pop 0;q(2. What are the tensions in the *lkswktp op8 3;aq(k0 ropes?

  In Fig. 4-2, if the tensions in the ropes b gp3mziau,s5*a 3*px(zn:tx are 50 N, what is the mass of the trafp 3 5p3gnx:b,a(szxtium** zafic light?

  Two boxes of masses m and 2m are in contact with each other on a:s bk 9sv8s+d ml3 gybc 3bi:e+5a8spvop6u d7 frictionless surface. l38ac mskusb83dpd 5g:9po6v b7svy++si: eb (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 fows p*/ek -j*trictionless surface. (See Fig. 4-3.) What is the net force on the mep/ s-*koj t*wore massive box?

  Two boxes of masses m and 2m are cqxk rv:/ore46t :i cr*onnected by a rope. (See Fig. 4-4.) If the forward force on the more massive bo rr:*/qe4:vr6o xktcix is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a ro b3bhe-vnd4 yo.w3 7prpe. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the accnbr7w3ey dvh b3-.po 4eleration of the less massive box?

Two boxes are connected 80v lzhfv.b;xb uu(a8g m9a5k by a cord running over a pulley as shown in Fig. 4-5. Box I of massvab 5ulfa;8.gvz8m(09ku h bx
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 friction6/u c;ysjl0ygx0j co+.ug171upw sll p+u,g bs between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied to the juj g0p06/7.+p,u1o slycsu c ;lguxl1yb wg+box?

  The coefficients of static and kinetic fg at7o2o/f0zcdpy1* k rictions for plastic on wood are 0.50 and pk201t zof*c oayd7/g0.40,
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 surfao7nb*o:c q d;gce in the +x direction. It slows and comes to a stop with a coon;b7ocg :q* dnstant 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 ivqifr80y * -k:8pdbbfs pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration rp*8fqi:k b-yfvd b80of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at lkxz cs0( 8kps 8e)tu9a 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 y+3 w+ncc3u2 j .tknmbm/s. It slides 50 m on the ice before it stops. What is the coecjnyb32 3 nw++kcut.mfficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, po( x(pv9xbb6mi7 bdgjude.4l5lice 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 prevailing conditio(jpd mbi4x9d bg7xl ub 6.(5evns. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-fb af s8n6 *9bmkw2+:3*bc5e, lhvuzp prz8bo6.) The surface between the more massive box azb9cn3zpkwbu ,l8hb6f* m r5 pao+:2s*fbve8 nd 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 less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface be +lfv27j q4uvw yziv gpd,.2p1tween 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 friction between dvp+.uvw4 lig vz2 ,17q2fpyjthe boxes?

  An object is on a frictionless inclined plane. The planw+ddo m29ukixpud,- )e is inclined at an angleo k9,du mupw-)+2 dixd of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides dowe9wr, )u:qkcf n a flat 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 aq:pb160qv v4cv64jarfqq gaj+q ;0qx smooth inclined plane 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 at d(s(hua1jh7oblk ( 3 xz)l zp5an 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 planef (2c/ qc.mw7g*z bhkp, at a constant velocity of 6.0 m/s* /ch7gfk. w (2bpqzmc.
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 swhe)/d1 +kxnslides 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 dr u(kyn6irv9wq: px0 7own 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 500 N along a rough surface. The cable i04xjlbbcc7g +i mm.2attached to the log makesc .jbmglm b4 7x+ic02i 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 tilted at a .d k-p+ai6gvz8 7gtkpn angle6tg kkg8 dvz ip-+pa7. 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 as7 k. umst+x)dw6h6tongle 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 objecto m6x wt s+sh.u6d7t)k and the plane?