Which of Newton's laws bes ab 3ba. q(4z0necr):h (rtrxbt explains why motorists should buckle-up?

  When you sit on a chair, the resultai;e (xu r0xj3hnt force on you is

  In the absence of an external force, a moving 3)wt -0,c5gr3b lrdfq kqnh p8object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turnedqo9l.6y2, qvxh9 rd .eq tma6h off, while travelievlm9,a9qqox6rht q6 .h d2.yng in empty space, the starship will

  A rocket moves through emh4eu +c9l irh;pty space in a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must b9 eh+u cl;4rhie applied to the rocket in order to sustain its motion is

  You are standing in a moving bup6bvdw b4e,pg5put0qu7li 0 0 s, facing forward, and you suddenly fall forward. You can imply from t 6 b5,w0pp7q te0gip4budl0uvhis that the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall forwar)9 u-q2ft3xxv3enjx f d as the bus comes to an immediate stop. What force c 9x-tfu2exx3 qn f3)jvaused you to fall forward?

  A constant net force acts on an object. Describe the motion of the ov,vs*r. qe4 iys/; pgnbject.

  The acceleration of an object;w e i 1bb,2ydazb-0qcc4 oui(s 5wj3b is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If th-wua 7xu0 ,y2s dv;-iqnn0sb ve same net force is applied to m- u sua; -xvnnbwy0v2q,is7 d0ass 2m, then the acceleration will be

  A net force F acts on a mass m and produces to4/7z mio 4-h eot;x y/zo5fjy(xs2*j c8dsg an acceleration a. What acceleration r(oeti -*sy fo ox/428z4cmhgj ;ydjzx/75o tsesults if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. Thisj /utjv7aey ++ is an illustratio+t+ajj/7eyv u n of

  Two cars collide headvcanc4 ;j:b(bh*2dy uc k vh(-f) q;uk-on. At every moment 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 car exerts on the y4u;)-kqv:*2hkcfda nucj( cvbhb; (first. This is an example of

  If you exert a force F on lsp u,ze 6clu31 3ah8aan object, the force which the object exerts on you willc sl u,zl31h8u3ep6a a

  Action-reaction forces. k*h8feda din,h+bboo zrkl(r6 5 *l4

  Action-reaction forces ar2 y ++ y6h(.rjesuvykje

  A 20-ton truck collides with a 1500-lb car :b rm;ynu irlan051x /and causes a lot of damage to the car. Since a lot of damage is don:;irylbm n/u15xar0n e on the car

  An object of mass m sits on a flat z pyz:0t+zt9 otable. The Earth pulls on this object with force mg, which we will calzpzyo09 +t :tzl the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The E1hepiy+8da;qf-xzb td i*yy *)we/.q arth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reactionh.pyey* d1b 8zi/ d;i*-w xyq +tqeaf) force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. Th7wv : ef,r4 an0vz5dzbe ba wn:5zez 4farv,vb7 d0ll hits the bat with an instantaneous force, whose magnitude is

State Newton's three lawse3.cqyde,q2wa1 19nczw gxj1 .

  Mass and weight

  The acceleration due to gravity is lower ncams-y(l6w/on the Moon than on Earth. Which of the following is true about the mass and weight of an mlw-asy(6cn/ astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts atqk 2h ll*nm.e*g+ 2ys0z1knljlo x.4r a distance is

  Who has a greater weight to mass ratyh.vr .ms70ek io, a person weighing 400 N or a person weighin .ks7.hmey vr0g 600 N?

  A stone is thrown straight up. At the top of itjy1 wiwdyg( wpz,h;*8 s path, the net force acting on it is y,w;gd wzpjh1 (yw8*i

  A 20-N weight and a 5.0-N weigg9 3x5o:ovrcg ht are dropped simultaneously from the same height. Ignore air resistagv35 c:xoo9grnce. Compare their accelerations.

  A brick and a feather fall t2cyxmf,8; cd to the earth at their respective terminal velocities. Which object exp;c x2 my8fcd,teriences the greater force of air friction?

  An object of mass m is hanging by a string from the ceilm7vupz(rq 7 a. xrd4-dqs8em wz:xt +1ing of an elevator. The elevator is moving up at constant spxawe v8m4rz:.7 q7xd p-(sr1 uz q+mdteed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an eleo4t,2jc;p0c(fbru6yav zxsyrl66;h vator. The elevator is moving upward, but slowing do z 6ry,6suh c bx6t;vyc(pj2f4lr0; oawn. What is the tension in the string?

  The force that keeps a9az48)x,)q ewf rocn you from sliding on an icy sidewalk is

  It's more difficult to start movinxz(vmm 1x 8j0ig a heavy carton from rest than it is to keep pushing it wm(vi1zj80x m xith constant velocity, because

  A horizontal force accelerates a box from rest across a horizontalygul9,k6 1hdv 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 is1gh9yd,uk6lv doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined rvgbcbps4*p7 g; 1crb3.k7tl ,a*ltai amp at constant velocity. Thus we can deduck47lrlg*sipc*p;t c1ta3,vgbab .b 7e that

  A block of mass M slides down a frictionless plane inclined at y7.ozhj+t v5 yjv7f.x an angle q with the horizontal. The normal reaction force exerted by the plane on the +7 j jyvo.x5zhy .7tfvblock is

  A block of mass M slides down a frictionless planx z9r,pn*9*v wmgvri d9;1 xxpe inclined at an angle q with the horizontal. The normal reaction force exerted by the plai ,9zxp rwxvrd1nx v*9;pmg9*ne on the block is directed

  A block of mass M slides down a frictionless planeuxdm2 e;adc47 inclined at an angle q with the horizontal. The gravitational force is dirxad;cd247u em ected

  Two toy cars (16 kg and 2.0 kg) are released simultaneously om 9-lvx5:nyvyac099c lb n 2awn an inclined plane that makes an angle of 309m2y 0nca-ax cvbwl9 nlv95:y e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionlem,i.z r 8zvd9fss surface. A 16-N force is applied to the object, and it accele, mivfr 98.dzzrates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest jl,y i5j(nafgz vn+f qu(kfi-f 64z0 2aoty*/to 27 m/s in 7.0 s. What is the average for(iqf+f / ( ktz0nvy 2afl5of6a,ujz*gjiy -n4ward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 je97 uom0zzye(v0 g9 ws. What is the net force acting on the bodzou zjmg(7e0w99ey0v y?

  An antitank weapon fires a 3.00-kg .imkc25zn um(rocket which acquires a speed of 50.0 m/s after tz 25imc(.ukn mraveling
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-kgi khp+0cggb l;afbhg y79+8p8xt s7a2 mass with the same force that you push a 10-kg mass from respc;7y9k+ ba ggg8+pf7s8x0l hbh t2 iat,

  What is the mass of a person wh, /qwl (h,oob29 e l*yjpcc8q 8syxe8ho weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surfacoy1 /keq )q*4 s5no:wtoze/lnkt*x4. lj qc h2e of the Earth where the acceleration duqehseqt*q1o o*/ kkz .ty52l)xcjnnl w/ :44oe 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 obje89+: 9ur je+liwxuqp nct on the surface of the Moon where the acceleration due to gravity is only 1/6 of that x+nrwqpeiulu:j+998 on the Earth?

  Object A weighs 40 N on Earth, and object tvp571j g)4rbg8yuaf B weighs 40 N on the Moon. The Moon's gravity vp)g yrug7j4b f81a5t is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposithix9 7:o2h ,9wgu muu2 ta7nica*i o2h t1/hnne ends of a 5.0-kg rope.iao /t uhxi2t:7n7choumwh h n*ag 21iu9 ,n92 Sue pulls 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 frictionlessj xf wk634f8mo ,lj-qx surface. A force F acts on the stack, and kmxf4w qlj o8j,- f36xit 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 sc.*xoxtt vm k30ale in an elevator. What will the scale be reading when the elevator is accel o 0kxm.3vtxt*erating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If +qqw*9vcg;ucw;c hmxv8, q 6athe mass of the person is 60.0 kg anxq 9uw+,av qcw;qhgmv6c *8c ;d the elevator accelerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rid9 fnj*2gmf9dce r lw68es in an elevator. If the mass of the person is 60.0 kg ag629 rn*jefdwml 8f9cnd the elevator 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 matb+s 0fqhom29ss. 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. What is the accb 9f2osmh t+0qeleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in pw2,4ot b qjvs;lace 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 , 2 ;wvb4sqtojstopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on th /dnue jnb3h- a f0xg5c4zg*2ee 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 the5hxf-/ d4*z e0cja bgg2n3u en minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown in Fi- , ortf/lnaso ;9 qvn03wfu4f0- sbjwg. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the f t-0 f3sn0- 4sno bfl,/w9;jqrwoauvmass of the pulley.)

  In the Atwood machine shown in Figja ;e17aru v(g. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore frictv1rg aae 7(ju;ion and the mass of the pulley.)

  A student pulls a box of books on a tv+29q zhb; er8i,aj osmooth horizontal floor with a force of 100 N qib , 8eor+a2jt;9hvzin 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 wihn .*nsfzojy4* htn *9th a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the bj*t y4 9fh*.hnsnn *zoox and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 8 t8q5* ;sitir*)zso1 uefkks100 N is supported by two ropes as shown in Fig. 4-2. What are the tensions ts o5ts*18z ;)k uq rfis*eik8in the ropes?

  In Fig. 4-2, if the ten+;/olj tck b/ 2oph)v a/zx(obsions in the ropes are 50 N, what is the mass of the traffic lighl+o vj2c hp;/b/oxb)tao( /kzt?

  Two boxes of masses m and 2m are in contact with each om62,wsux v mn18*y rgzther on a frictionless surface. (u 8msg 62n*xv rm,1wyzSee Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m (u oujl/1s6hs0n m (r co3b,isand 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.)6ol 31muhnbsu(/c i jss,(ro 0 What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) wvb i/ tqxt 1ntvxl0/w573 pq6 If the forward force on the more massive box is F,wt lqxw05n /x3it6v/ 7pvqbt1 what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. +:4 hsrfah2menp h 00o(See Fig. 4-4.) If the forward force on the more massive box is F, whamh:4 e+0hp aorn0fs2h t is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in F)3lzs+q+:uzb-)h0tgdk+ -spms sicu ig. 4-5. Box I of ma u+s bc+k zm- pls)qiszudgh )+t-30:sss
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 sm))feae.z 22yn1fc n 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 app 2ens ffmn1 )2)a.zceylied to the box?

  The coefficients of static and kinetic fric6/neqh pz4d .yhzmb hwk(-;x3n c) w7qtions for plastic on wood are 0.50 and /7hkbpw(qnzy; dzm c4-w6h. n 3x)qeh0.40,
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 dw bkh7b +x llge y.opj/uow1 1(3cqyvbg12,1lirection. It slows and comes to a stop with a constant acceleratebulbl/o(.y 1plvyw3 q 2 bo1w11xc7+,ggjh kion 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 horiu0/et6p, fnlm ;ux ta;zontal surface is pulled by a 5.0-N force. A 3.0-N friction force u;x/ f p lue;am6t,t0nretards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelepcsangivw7 x8/54*t*; 7kndmjhbc; urates 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 game, a puck is given an ini j9j(bluf2c08axi1 u ltial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the u c198ill 0(jbxjau2fcoefficient of kinetic friction between the puck and the ice?

  During the investigation of a tra7or8gt7 lr k3uffic accident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway t73rug ol8r t7ko be 0.500 for the prevailing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked cs8 (;v b2vawo2an)zl. (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 vs zclv w8)2o (bn;aa2the less massive box?

  Two boxes of masses m and 3m are stacked. (See Figt f28 cs.8z9(kv fv n2j14twqox:pfaz. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. Ifvt42z 8 . tn jzksva289o:pcfwqf 1x(f 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 is inclined4lsq tmw 0i9p- at an angle oq iml4sp9t0 -wf $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle of0. oq26gpp -g frywi;j $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclined plane wiub86r;6l(ws5y3w jyxw. umdc th 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 a k8pm7o;nl5 lplane 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 incl2zy-ija8w l ffi il (/m5zpnt 6:1dc;gined plane, at a constant velocity of 6.0 m/s.z ;l f2ij ap5i1w6-mlin8zy/(ftdc : g
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 rou t0fu6jpavw 70t/o,gqgh $37^{\circ}$ 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 ror+gphcq p58, zugh $37^{\circ}$ 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.vxw4(paapo-va1* c0ign: - mg The cable attached to the log makes an : (a1g- aoac i0 mxp*-pgv4nwvangle 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 un); vdnac o+9rough inclined plane tilted at an angle ofd)ovnc 9;a+u n $33.5^{\circ}$ 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 inclz.g 0b609 qpc5ts:dleenq8p o ined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient o e9g:l oet8qc.p6 qpsnb0z5d0f static friction between the object and the plane?