Which of Newton's laws best explains whyk4p+j iz pbkx6w:ye7r*ca9rr5a, oh4 ox01rz motorists should buckle-up?

  When you sit on a chair, the resuln )hz1s3ay74( wvp7kw i;yec ztant force on you is

  In the absence of an externalyw4 e/ bvpmt1 b0j2r13)neajn force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turb9z lya+ )ndfmo 1o.h,q)iax8 ned off, while traveling in empty space,q9ay)lmo.xo a +bhnd 1, )8fiz the starship will

  A rocket moves through empty space in a straight line with cms9c(0w,4g k0:zsm spb+ax fv onstant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that mub p0k9 m s(c ga+vw:mz4ss,fx0st be applied to the rocket in order to sustain its motion is

  You are standing in a mov7fx5 lr6 saw,ay opx0-ing bus, facing forward, and you suddenly fall forward. You can imply from this that the bus' 7-aafxwry5os6 0,lpx s

  You are standing in a moving bus, facing forward, a a 8y/.,nd8 p-h5ug; foa,vaohgsp5fi nd you suddenly fall forward as the bus comes to an immediate sioaa58sp,f ,g 5vn-yh8faod/;g .hp utop. What force caused you to fall forward?

  A constant net force pk 5;fhc. hhy8acts on an object. Describe the motion of the object.

  The acceleration of an object u. mehn.o te4cfz.+vav ; 7qw:d8/nxkis inversely proportional to

  A net force F accele19b u4 9u7:xknyiwn hhrates a mass m with an acceleration a. If the same net force is applied to mass 2m, then the acceleration 1 kx:w hni9b4u 9h7nuywill be

  A net force F acts on a mass m and produces an acceleration a.zs6qmze ijbg)9,72sbaziu l/ d4 6d7q What acceleratio6 a sjb )izm/4euq7qigz ddblz96s,72n results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and th) 7-yshgizwvux.q-c:ip m( 2ten release it, the balloon will fly away. This is an illustsxip-cq.2w7 )(i :-gh v yumztration of

  Two cars collide head-on. At every moment dvw7vkssd)*h:a ste.9ewi,w6 uring 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 first. This is tv96*v:ew. es,i d7wwk)ahss an example of

  If you exert a force F on an object, ty;v;qxn al1flry*z0y3v3s ym0s . g, rhe force which the object exerts on you wi,ymzq ;g.;r 1 fl 03yslsx3ya0nr* vyvll

  Action-reaction forcegcx(u6(vrav um+ 9*vqs

  Action-reaction forces g1ufqnp(t 3v 1are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to thedyvt 890 bnjn95nrh 3e car. Since a lot of damage is done on 30vhbn99tnj 5e dr8 nythe car

  An object of mass m sits on a flat table. The Earth pu3j zk0k 8tvapyih7 2;clls on this object with force mg, which we will call the action force. What is the reaction fk7p h3;y0 2i8zkvcjatorce?

  A child's toy is suspended from98: +(zmm0z 4vngpx0kbo pxp)o 2vjrl the ceiling 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 forc8:o l9p +porv0 2pk m(4xzn0)gzbv mxje," what is the "reaction force"?

  Your bat hits the ball pitched to you with c+n( vndbelt m:b/6.j a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose magnt.6mbn +v /:bjdl(ecnitude is

State Newton's three laws.fq ::n9 al6*l9sht3pbg8gi go

  Mass and weight

  The acceleration due to gra a.d .elx1 oj0zdcgs31vity is lower on the Moon than on Earth. Which of the following is true about the mass and weight of an astrj e1.l03 og d1zds.caxonaut on the Moon's surface, compared to Earth?

  An example of a force which acts at an0w +l.e yq0oh distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person we*xuv tp/fp08zighfz8*x v0 p/upting 600 N?

  A stone is thrown straight up. At the top of its path, the 1v3r6 etyh6lsb)7e kb3t6u(tv pul*knet force acting on lrst)k k*t1u(p6l e6 3v3e 6byhbuv7tit is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the s.v7,qih1npa 0uj8it iame height. Ignore air resistance. Comparp ni.1u,ai tjqvi8h 70e their accelerations.

  A brick and a feather fall to the earth at their respective te x7*sk0 h ydvv kz43gficz4x*,rminal velocities. Which object experiences z h7k*4 k x0gs43*civfdxy ,vzthe greater force of air friction?

  An object of mass m is hanging by a string from the 3) ufi:vwb:i xceiling of an elevator. The elevator is moving up at constavi u:wf 3)ix:bnt speed. What is the tension in the string?

  An object of mass m is hanging by a string jtzbsjf(9n9da1:cs4n8 ffa ta7:0xw from the ceiling of an elevator. The elevator f7a1 8sd 04 jaxcsfwjt b(f 9nzn::9tais moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from slipswz1pm1 zts(2pbbmq5zf8dc -z ;6j5 ding on an icy sidewalk is

  It's more difficult toz l w1 j/nfdc,d16n.ya start moving a heavy carton from rest than it is to keep pushing in1zfnld,ad6 yc /1 .wjt with constant velocity, because

  A horizontal force accelerates a5pzkan7 gt1s * 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 1tz kp5s7 agn*doubled. What happens to the box's acceleration?

  A packing crate slidkjp a:v/lh)p90cw v:tes down an inclined ramp at constant velocity. Thus we can dl:t9hp:j vw0 ak) cv/peduce that

  A block of mass M slides 3jxxe,udv v* pin;)pf4v/ mv .down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plev*)3 fu.;iv,vj vm/pd xnp4 xane on the block is

  A block of mass M slides down a f(3r ; 1+ k(g,7urwghc edtqwvvrictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is dirc3g;tverw1,(uh+ wrdgq7 k( vected

  A block of mass M slides down a frictionless plane incla w3 ij;nw*l tl-mu7v,ined at an angle q with the horizontal. The gravitational force islj -7tnw v,mu; ilaw3* directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an incliplgkey5(l0/ /hf u/csned plane that pk ll(fs h0u/gyc/5e/ makes an angle of 30e with 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 applied to the obj(t;mjvut ,b h6izw- m1ecttmu-( wzthi; 61vb mj,, and 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 rep 3yqqtr* t(aou5n+bx zjj0.- st to 27 m/s in 7.0 s. What is the average forwa tjb rnay*p(q+5oqtu-3x0.z jrd force on the car?

  Starting from rest, a 4.0-kg */ptz uhf3 9jebody reaches a speed of 8.0 m/s in 2.0 s. What is th*e/ fhz3p9uj te net force acting on the body?

  An antitank weapon fires a 3.00-kg rockeq+w mn0 x,8 u jsqj9b(:7ssd9pwi dj8jt which acquires a speed of 50.0 m/s after0 s7sdwqx: ,ujd8ips jnwj8qj(9m9+ b traveling
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 sam h/ cyx8lv9s 8d7kexq2e force that you push a 10-kg mass from restxvx2/8 y s78c ekdlhq9,

  What is the mass of a person who w72 6 eh(ko t5jb1lx dmbxyp5f/eighs 110 lb?

  What is the mass of an object that weighs 250 N on 7qnw/h c - iyuom0/wkq(aj 6mr c1.mck075uxxthe surface of the Earth where the acceleration due qu 7koa y0- .(rw01jmcwxnq 5/mm6x hc/icku7to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on theghv ssr(gr 5lyv6.0v h689z ks Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravitrg8lzshkvv65vr s.9g6ys0 h( y is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Morck.m+d .a:eg on. The Moon's gravity is one sixth of Earth's. Compare the masses of th :d.r+ckemg .ae objects.

  Sue and Sean are having a tug-of-war by pulling on oppositejb)g3lmz / 9ebnsy;*h4-t 5 v, lisudh ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates towary ,md)h*n3ts9l/jg5-blvzse 4 ; bihud Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F p*oi3jrrfmjy,9 3: oeo2+ociacts on the s2*oor ,c:p fiooirye+j 9m j33tack, and it 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 scale in an elevator. Wha/ *8 q0q/mdxzp.ycaoot will the scale be reading when the elevator is accelerating down*zm8a/opc/0od . yqqxward at $4.00 \; m/s^2$?

  A person on a scale rides in ao64wofkp 0pm5(6qcda;g ze c 7n elevator. If the mass of the person is 60.0 kg and the elevator accelerates downward withmg 7q dc5 z po;0fa66ceko(wp4 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 mass of the person is 60.0y.4- 1sud 0;iack vdxq2zbk: j kg and the el10q.u; xjv:sc-d 4ya dbz2 ikkevator 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. Onelfz ,6fti+fmhr0u - m4 force has a magnitude of 8.0 N and is directed due north. The second force if60fm -u+ zfht4rl ,mtoward 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 trutmzb8991+(i kdg zzpe ck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is trz1+bt9dp8 9zmk ie( zgaveling 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;p +04cr5:id-rgfxy s 6ysl xq 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 5:yrc-gl+yf;dx4px r 60qis s15 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 and m = 0a3ci 0d5d52w rqs):gbwaq hn gaf5 ,u/.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the massa)5rq 3diq ,52ufwas/h b ng:gda 5cw0 of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if 4wm8j ,c-6mii ksfdnx/uoh70M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignid4 68ujf,ni7mw0 c mo/skhx-ore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force o ztvrltq(5 d9;)p (zv(jl3kk 4l 8fjbnf 100 N in a directpzk lj bj 39dlkvqf);z((l(4tvn5 t 8rion 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 flo5sd 1vttxl 3c5 gfda):or with a force of 100 N in a direction of 37.0e above the horizon ldgvd s3f:at5t 1x)5ctal. If the mass of the box and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weightxw,oz1x,v5b25f h sf c 100 N is supported by two ropes as shown in Fig. 4-2. ,co2hf5x w5b,v szf1xWhat are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes ar hxb7 fjj0 --17xlwxsh/j/lev e 50 N, what is the mass of the traffic lighxw1-f/7shxl-jhe7x jvl0j/ b t?

  Two boxes of masses m and 2m l 3xh7; s9e1 7w6 px i*pbujkmcgp2uu*are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the mju c2 3xs7p91upwe6*pbxl ug*;7hkimore massive box?

  Two boxes of masses m and 2m are in contact witld26k8l 6(cgrjgtvu 5 h each other on a frictionless surface. (See Fig. 4-3.) What is the net force on thg2l ugv6 (85r6djl kcte more massive box?

  Two boxes of masses +bpk v)n7)lx .j 0 ju/ir6tprum and 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, w)7+blr6t 0xnpj/ kj upv .)iurhat is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Ft9 nm2mf* oaa6ig. 4-4.) If the fortmaoa* mnf296ward force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connect kbb wqh w9rcro84;jxu;ot++3ed by a cord running over a pulley as shown in Fig. 4-5. Box I of ma8uo3r bwwbk;+rqot ;+4x j9chss
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 betweenmxfic0ti we)a nj l9n,9 qio36kh(7t5 a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is t(7,069ae9i j qklo h5nmcwi xn)it3 fthe 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 wood are 0.nf6qg pw4m:,o 50 and f p:nw4qm, o6g0.40,
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 i*/ofeu l2 cwc7n the +x direction. It slows and comes to a stop with a constantc w7u*lc/2fe o 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 surcu4z84zo ec u6mrz j)q2s+:pyface is pulled by a 5.0-N force. A 3.0-N friction force retardsr4 6uu:sqc+)8ez mjy p 2z4czo the motion. What is the acceleration of the object?

  A horizontal force od:qik krk4 eg.-sv1:*xdm s.yf 5.0 N accelerates 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 pv:v/.. bjr *st3 ymd8xed:zjpuck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic fricti.r yxpe ::svjm 8jz*3dbd v/t.on between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks*c;5* gfnkb cy 90.0 m long. They determine the coefficient of frib;*ny *5c fkcgction 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 and 3m are stacked. (See Fi* umcd j24l +k-*mnopzg. 4-6.) The surface between the more massive box and the horizontal surface is smooth and thol*+4 kc *-mzd2pu jnme 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 agzc-(tzdd l 2xux(7 z3re 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 friction between the boxes? 37tz2(ulz -gddxxz( c

  An object is on a frictionless inclined plane. The plane is fh 39axgk aix u*t538qy1) hczah;tc3inclined at an angle ochtac83q*;1) uy33tx k zghf aix5h9af $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides d rk8ml0z/khbj4w4 9mtown 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 a smooth inclined plc goeqy.m;0e) ane 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 inc jf84* 1ffrnt0tsyx anput2.7lined 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 constant veloec,rmk0j x+i2city of 6x+jr m,0i2kec.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 m slides down m7s4ji 8;llqy6 1qvju 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 a rough suvbbhu)0 ql5l 6;z: 9ck4dwu$37^{\circ}$ 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 alon799nn*gy mooqg a rough surface. The cable attached to the log 7*qg n99omoynmakes 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 a1dxy4nfd**o;r. sy em rough inclined plane tilted at an angle ofyn*s;. drf41x* omyed $33.5^{\circ}$ 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 a-ex -+uz ff/,iml/gp zn inclined 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 of static friction between /f u+gzml -/ zx,pfi-ethe object and the plane?