Which of Newton's laws best explains jgh ts(kg*qjy)fk,(8why motorists should buckle-up?

  When you sit on a chair, the resultant force on you is sh52x6xr 7 qi0+gzpjk0 if3ho

  In the absence of an(- 8ujkc2i uef external force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN aru4z/)+t1kfo )tb1zoch 8 gzn,hrv yk+e suddenly turned off, while traveling h+z1)r+o)kb1 hzf vytoz/4 k 8c,u tngin empty space, the starship will

  A rocket moves throudl/t* y,c*w lzx 6jcj,6u2pb vgh empty space in a straight line with constant speed. It is far from the gravitational effect of an6y**zc vjt6,ull w /c2xjd, pby 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 movinmrl,2w*.j iob0 +dp lrg bus, facing forward, and you suddenly fall forward. You can imply from this t ldp0rrwo.jb2,*il+ mhat the bus's

  You are standing in a moving bus, facing forward, and ny*/s b;vos e ir31/vcyou suddenly fall forward as the bus comes to an immediate sto y1vob/sc*r/;e i3sv np. What force caused you to fall forward?

  A constant net force acts s) )1p 3id.9wtqib ;n5 ln/mz-edvunuon an object. Describe the motion of the object.

  The acceleration of an objcuj+7eou .ucp96sd 1c52luy n ect is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same neh0vsd3k8p rb4 t force is applie8 vb pkrd3s40hd to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces a qxw,wju a7d64b:gvx+f-3k h on acceleration a. What acceleration results if a net force 2F actd4jk3-, o va uxfhbx+6 qw7:wgs on mass 4m?

  If you blow up a balloon, and then release it, --ri/xb;gn lqthe balloon will fly away. This is an illus-q /gxl-rbn;itration of

  Two cars collide head-on. At every momentn -tf cuy/-ojv 48r3uekfqq): 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 se-cffo4v n:/k8q3qr -e tuj) uycond car exerts on the first. This is an example of

  If you exert a force F on an object, the force which thee*5 hro p2p;24oyrp, chtihny54 (shr object exerts on you wilhcpr(o4s4 y ,re52y5hhh tp; *ior2 pnl

  Action-reaction force 9,errocxu3i ,.:nhm ls

  Action-reaction forces a zb(n(yryh,v6 rt+kb, re

  A 20-ton truck collides with a 1500- aus;4z57 ykmeyjeu 4;lb car and causes a lot of damage to the car. Since a loesk j z75;;muuyye 44at of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this objec ydc 7*fvxnhuz )6.co1t with force mg, which we will call the action force. What is the reaction forcex u .cvofy1nh7)d*cz6?

  A child's toy is suspended from the ceiling by x2/-*+yfz/kut8baqvzrm 3ku6a 8wo p means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force88//r6k2wy mz aou3-kfxut bqa +p*v z," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-7d.nfzt s)0d p-k br.sN instantaneous force. The ball hits the bat with an instantaneous ksr.fd. 0z-dp n) b7tsforce, whose magnitude is

State Newton's three lawsp fd0o mkkj(8dqqoz9: +zyz/ +8emb2n.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which; w 5 .nvz8inxnag69 ej1xi:-h fxr8ja of the following is true about the mass and weight of an astronaut on irnnzgw a ji;51jhx.nx8 8-aev:96fxthe Moon's surface, compared to Earth?

  An example of a force which acts at a distancciq17 a-(36ofp top gufy3z m/if/bj5 e is

  Who has a greater weight to mass ratio, a per6bw uk43a*vw 2 :yl9chsmt5tuson weighing 400 N or a person weighing 600 uww9yt 3k 5*6h4b:ma utc2vlsN?

  A stone is thrown straight up. At the top of i-w..ad9*uzf : pumrnl ts path, the net force acting on u awn.p m9:.r-*f uzldit is

  A 20-N weight and a 5.0-N weight are dropped sim0uq*lvpv t u6y ojh-01/ f:2 izeo+dhzultaneously from the same height. Ignore air resitfhe2h z/: ov6o1 uy- +0dviqupj*lz0stance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velocitiegqfec s19 s6x /kvk3/ns. Which object experie/ s69vkn 1/c sqfxek3gnces the greater force of air friction?

  An object of mass m is hanging by a string from the cei ot8l).2yb jviling of an elevator. The elevator ioi.yb 8j)vt 2ls moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevajd )l0rhk71;j bg2del tor. The elevator is moe g2lj1d;hkbl70r )j dving upward, but slowing down. What is the tension in the string?

  The force that keeps you from slidijrt kbp l h2yl8-p--n9,gw3l6s od;xzng on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is txtge96 9 qdvvnju 74e2o keep pushing it with constant velocq6nut4eve7jg2d 9 9xv ity, because

  A horizontal force accelerates a box from rest across a horizontal nvnkq* (1 v,rsonl*y5surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exceptionly(n k5n1v ovsqr ,n** that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides dowq1 dz cgv6o2o9)ro zy rd4vrm6;7 tao-n an inclined ramp at constant velocity. Thus we can deduce;7-d46 q9oooc 2mo6 a) tzrvyz1r dvrg that

  A block of mass M slides down a frictionless plane inclined at an anglyap3 ( 4jlxm2pe q with the horizontal. The normal py axj3p2lm4( reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane incline)6i3ueuo yqgar 0e9/hd at an angle q with the horizontal. The normal reaction force exerted by 6 a)e9/urgueyhoiq0 3the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q wo1zi-wcspmo6e f((rsw 6 i00 zith the horizontal. The gravitational fof(iom(cp -ez oz0si0s 66wwr 1rce is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined p/ -. sf km.;:g;qsdr 9bd/ kfhioetv0wlane that makes an angle of 30e with the hortv fhss. d.kmg9 f/ :ir;e;o/k0d-qwbizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictz mm.4: 30iwrpybs nq0ionless surface. A 16-N force is applied to the object, and it acceleratessw 3:pm b40iq0z.n mry at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acceleratf 6ii. t:kxej.e from rest to 27 m/s in 7.0 s. What is the average for.ftxikji. e:6 ward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of l9 zfrp(o ,5urobh( 2p8.0 m/s in 2.0 s. What is the net force acting on the body?9bur,z(p o(l rh2o5pf

  An antitank weapon fires a 3.00-kg ro*t2uo4z t95kyyhps: l cket which acquires a speed of 50.0 m/s after travy ltz2*u5yp4: kht9s oeling
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 pushme,cs6( itt5wmp(n,j8 f pd)f a 10-kg mass from re(i w5jp6s) ,p,(eff 8dttcmmnst,

  What is the mass of a persk2q9fs b0 r l.r.bt*jion who weighs 110 lb?

  What is the mass of an d(sc :ttc:/s4 zkl 2dlobject that weighs 250 N on the surface of the Earth where the accelers /lt dz 4dck(s2ctl::ation due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earthv4sgtv*da(+we +q a 1t. What is the mass of the object on the surface of the Moon where the acceleration (wvdv++a *ga qt4t1esdue to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N o3: n xa (weeofh,+iz9xn the Moon. The Moon's gravity isxn(ei 9+w:ofaz,ex h3 one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by puflfmb 9i3/*qtp c 1a/jlling on opposite ends of a 5.0-kg rope. Sue pfp91mb q/*l fct3a/i julls with a 15-N force. 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 frictionl5+c 8u3t9 : n8pbq ttdz6gbibyess surface. A force F acts on the stack, and it accele3:dz6q8n5 +cu yt9 t 8tbgbbiprates 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 48lu1vtu0wy9-un cb op3y2i rr w;zy9 9*0 N stands on a scale in an elevator. What will the scale be reading when the elevatoy 3 wp9u ni9 u vc0*r2btzyr1uwyl-o;9r is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person isq f8r8q;yf. jq 60.0 kg and therqjq 8q8ff;y . 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 ma 5;jyqib8i4hd */w rplss of the person is 60.0 kg and the elevator iq*hb4r yp85dji/;lw 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.tj w)y3hh *ji9 One 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.y)hti w3jh9j* What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It i ytr 7ygm;;xv an*w03ks held in place by metal brackets that can exert a maximum hory vn37g yka*0x;mwtr; izontal 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 the8vjyltrj)) t+ flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force +yjt8vl) jr t)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 rv7dxsd,j7ns( hw5: j and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of the pulley.)jhj s:dwr5n( 7,7sxvd

  In the Atwood machine shown in Fig. 4-1, d ko87jfwe 9uwgj,o71 if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the maj,78f9djgeko7 wow u1 ss of the pulley.)

  A student pulls a box of books on a 2mjjr 5l kc96nsmooth horizontal floor with a force of 100 N in 6 5c2mnrjjkl 9a 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 sm5 ao 2bnjt- hhd0)8ydmooth 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 is the normal force on thethd2)ydh0 ojm a8b -5n box?

  A traffic light of weight 100 N is supuos *e9jy1wi4 ported by two ropes as shown in Fig. 4-2. What are the tensions in the ropes 9wej4soui1*y ?

  In Fig. 4-2, if the tensions in the 3.k o :cm)6krgz:i++e (i djimb0 vosdropes are 50 N, what is the mass of the traff0:+smdi i6)3 +k:.mr (evocbjiko zgdic light?

  Two boxes of masses m and 2m are in contact-zw 1dmjjl nw)w5:y9 c with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of w mw-w lc9:z1n )djj5ythe more massive box?

  Two boxes of masses m and 2m are inmcvlt ;+5-ysb0:xv ea contact with each other on a frictionless surface. (See Fig. 4-3.) What i t05sxyca-+e b vm;:vls the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope.-ih,ibv j0 am9 (See Fig. 4-4.) If the forward force on the more mb hv-i0a ij,m9assive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope6+0c-bz*b e x;dajek k 4t+lqe. (See Fig. 4-4.) If the forward force on the more massi +dcjaz eqe* k ltbe+0x4;k-b6ve box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over 15;es6u .a5 swh x/pqt9owxar a pulley as shown in Fig. 4-5. Box I of ma9s6 ;rsuqt.p55hxae/w1wox ass
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 fric*s ue/6bmwu :vtions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the n/6 wmuu:vb*e set force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions fp7io 3 ixp() hs0s:zjk(br :pjor plastic on wood are 0.50 an:xs37(bpoh k) (j: jsp0zpirid 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 +x directzjdx*au2+2.i ixm r -:)uuhb fion. It slows and comes to a stop with a constant acceleration off dur.a *uzhm2xi -:u2)+ jxib -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on ahjr0: n5zplg3a)pp;xt+ 8s bx horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force reta)b5ntga :xp+php;83 r0jz lsxrds the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg massvzp p90;o fknh5z 4re/, 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 game, a puck is given an m e(spfam4.o : u4cxxa0x; 5mjinitial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the cojau04axxmecs5 (:x.f; 4mompefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic adxzj00 f;;nw 7-egnqfccident, 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 q70xz;deg ff w0j-n;n for the prevailing 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 surface bd whw* +jkyd hs96.f sjq6c78setween 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 slj9k+shd 7ywq c6 68sjds. h*fwide 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 behmisg 2mrkb0(+r4 ke)tween the )kigm2mkr sh (0b4er+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 the boxes?

  An object is on a frictionless inclined plane. The plane i7dfes)o mwr ()s inclined at an angle ed) w7osr(m)fof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that ei m/y d1-wq,4lj5vuzmakes 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 sme) f1zstu/ -loooth 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 an angub2sw o/a3 ,ot q) qv fx6h/msjqlo968le 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 caj -kj s43cy1u5 ay;5b8cc shzc rh+-uonstant velocity of j- ch8cbys-ccu5 r azyu431; a5jkhs+ 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 mass mc 0yy u3tl(a:v 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 aq1fz aok kv87cw-:jv3(2pi lm 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 rouutu kj5m c69t1gh surface. The cable attached tocmt591tu6 ujk the log 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 fr(y6 dr-am6xmd om rest on a rough inclined plane tilted at an angley(ad rm6m-d 6x 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 de+ tb:,8qcfzvs- 7t*dyrv +uof 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 betwee,u+y b+v7v8t:e-czfd s* dtqrn the object and the plane?