Which of Newton's laws k w)8wphcm1w cj(3+; gf vjhe0best explains why motorists should buckle-up?

  When you sit on a chair, the ra+/ zwuy n-i(be-,lju esultant force on you is

  In the absence of an external force, a movi * m: / kn9u+gnbo-oyuqvcc:3nng object will

  When the rocket engines on the starship Ndxfzx27z/rn( *d uj3r O-PAIN-NO-GAIN are suddenly turned off, while traveling in emptx23 rjxn7uz(z rf*/ddy space, the starship will

  A rocket moves through empty space in a straight line with constant speedtrf x 4wssc:yub 92c uz*w7)+m. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocket in order to sustain s)rzb : xwmts2cyu7u+*9cf w4 its motion is

  You are standing in a movin: q.7 zj-ixtnsd (ri;vg bus, facing forward, and you suddenly fall forward. You can imply frd7izvir-t.;snj ( x:qom this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall forward pez lce ;ay ;psa05+5vas the bus czyv;0e p;5ap als5 +ecomes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the o+wemihjn .wn4 1-4ieq0 l0wqqbject.

  The acceleration of an object is inversely p zrktepq3c g(1(6; nllroportional to

  A net force F accelerates a mass m with an acceleration a. If the same net o-3 nm4-ae mslforce is applied to manmas m 4ole--3ss 2m, then the acceleration will be

  A net force F acts on a mass m and produces an a vdwcadm71s- 6cceleration a. What acceleration results if a net force 2F acts dw67 vam-c1sdon mass 4m?

  If you blow up a balloon, and then relee2b(, yrqucyvhy) 0c9j 0k3wl ase it, the balloon will fly away. This is an illust 23ywb)clykvry9c,q0 ej uh(0ration of

  Two cars collide head-on. * h6*5+ln;3koalogms b5nlx q3xliv 3At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of tmn*l bg;+35n3 qx s 6lv 5*hllaiooxk3he force the second car exerts on the first. This is an example of

  If you exert a force F on an object, the force which theaw )2lgw3pp0a d*xkq; object exerts on you wi*pag2 ld03kq; w wxp)all

  Action-reaction forcvn()xxy*+wprb .x * rghsek(2es

  Action-reaction forc ykt5n/tk;ng9a:dq6z es are

  A 20-ton truck collia 8id hwv,xrp2tle0. 7des with a 1500-lb car and causes a lot of damage to the car. Since a lot of 8er.ihl da 20twpx7v, damage is done on the car

  An object of mass m sits on a flat ta h9 soex )gus.9tze*)lble. The Earth pulls on this object with force mg, which we will call the 9tze * xlhu))s 9soe.gaction force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of k55kau f/ 0yyv aj rqjm3x2t.8a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the5ftx. ukm a32/0 kyj5a8yjq rv "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. Th q)wft51s;w4vp()naei tq63kou tdeyi-+m 6 qe bal)tm6su ;wqi evnf1-3 qd t5ty+ wa (i6qop4)kel hits the bat with an instantaneous force, whose magnitude is

State Newton's three lax(1nz2y(al) prn/ jlpws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon ths-ni p0:k -7yoast 5mpan on Earth. Which of the following is true about the mass and weight of an astron50yms7i:n a -tp p-ksoaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distance ija*6gqn mdz as +f *l)0p*f/6ny scvm9s

  Who has a greater weight to mass ratio, a person v+:b l 7*( rvj;oas0y akr4bjnweighing 400 N or a person weighing bbk4r( 7vavjsa:+ljr on ;*y0 600 N?

  A stone is thrown straight up. At the top of i2nr t3z-sup0n o4j7ewts path, the net force acting on it i j7e 0tw3p-nzn sru2o4s

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the samt-te;gydlvxg5fwz-( .s 5 g6le height. Ignore air resistancg; g xs--6z twfged.l(t5yvl5 e. Compare their accelerations.

  A brick and a feather fall to the earth at their respective t*y /dqc;k;cl) krc6cgfy c-d 2erminal velocities. Which object experiences the greater force of air frictio ;; / 6fq )-cccgdyckkc2yd*rln?

  An object of mass m is hanging by a string from the c7nl9g. z2r7uxu7 prytkf s03u eiling of an elevator. The elevator is moving up at constant speed. What7zux.u k9g0rr2p f l7 7yusn3t is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevator. Th3us+lz- . +hfe-gbtt we elevator is moving upward, bututl 3gf++zet - s.b-hw slowing down. What is the tension in the string?

  The force that keepsha r,;z *ax8eymx2 :qc you from sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton fro-qz(o on*v+jrmp *l1 ym rest than it is to keep pushing it with consta*1o+pny(vjmz l o*q-r nt velocity, because

  A horizontal force accelerates a box from rest acr;;s. 1 opgk*/-rdvijj 2eqzsqoss 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 doubled. What happens to th2qs ./qvj;;kizjreops g1d - *e box's acceleration?

  A packing crate slidv8ewwml 9z ck8h px; *5ht14eres down an inclined ramp at constant velocity. Thus we can deduce crh* e985phkx4ez81w;wl vm tthat

  A block of mass M slides down a frictionless plane inclin;zt7: iawjsc)m e.f5hed at an angle q with the horizontal. The normal reaction force exerted by the plane on the b.a: hwsje57t) i;cf mzlock is

  A block of mass M slides down a frictionc f)pv/9)2exs ax, vz3p sh lsrxkmj(r87+r 9uless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane )xa zr,3krsvj7u9h 8 e( mf/ )v9 csrls2+xxppon the block is directed

  A block of mass M slides down a frictionless plane iz6wgl10 84hiaa4qa2 ( dugu/oc sqh2c nclined at an angle q with th 2qiuc1g u qa hcaa8 ls/64d024wz(oghe horizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultanza :555 *7yu:qx2vh il9b(hmtmwd xhh yl93s keously on an inclined plane thzim5 l7m:h2d qy9:h5v (yaxstkhlwb5uh3 9*x at makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionlelzs7 ;/ku1d m5x ddu0iss surface. A 16-N force is applied to the object, and it accelerates ati5dkz7ds/uu1 l; xm 0d $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s-si * +18cni e9o jzxv67eo; ui1wpijr in 7.0 s. What is the average forward force on thpo e8ur1i v 6isc7 nwi1e 9jxi-j+*zo;e car?

  Starting from rest, a 4.0-kg body reaches a spvkw c8(-ssb0w.wt 8teeed of 8.0 m/s in 2.0 s. What is the net force acting v8.wwc es( tk-b80wtson the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m/s 1ue+ wlts0u pd*q;o;v after travewq+t v;0s;uoe dl1p u*ling
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 for-d8sa3 v rj8*ze:cvhd sr* u;ryn z*9jce that you push a 10-kg mass from rest,vrrz c38 d j8je*y*9*r:v;sasu nhdz-

  What is the mass of a person who won :gmdj49*l2*a kyw jeighs 110 lb?

  What is the mass of an object that weighs 250 N on imq5 q3)*xhgf.cf9m vsp,l2 v the surface of the Earth where the accelqsqff3,*m2hv.x )c im9lgpv 5eration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 k14wx zy3upks1o) e.xja 71*qjffie6 vg on the Earth. What is the mass of the object on the surface of the Moon where xk73q ju*yov6j 1epfi)s4wz.1 ef1xathe 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. jt:i*,)ggzt dvugy-c8 nm 4e:The Moon's gravity is one sixth of Earth's. ztdggm:vj -8 t,n: ue*i4cy g)Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on:zjecp 0 bk:+n opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope a:b:pcn0+ kzje ccelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a le mi7xlj h oa-yje2/:+ivel frictionless surface. A force F acts on the stack, and it acce2 me/ l hai-+:xoi7yjjlerates 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. What will thep/ y1..avqkrf scale be reading when the elevator is accelerating do/ ayf.kvpqr 1.wnward at $4.00 \; m/s^2$?

  A person on a scale rx.k2 fbvu/u.) yntfn ;kzf/dts17j h2ides in an elevator. If the mass of the person is 60.0 kg and the elevator accelerates downward wix/htfs2 v.znk)n 7/f;ukujdby 1tf .2th 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 personrs1-vs 3 qygqr ppx0j0,vxlrs lgi- zn*q0 *,0 is 60.0 kg and the elevry,,0l q30 - v1lg*qgriq0p0 jprsxvsnz*-xsator accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on v p,d5/eif fss3ejv v)q+a2 8xa 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east hassv5p ,f)e v+/j8 qa xf3i2vdes 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. It is heldc( v .h+(ggt94brfud7fh o b.h in place by metal brackets that can exert a maximff( ht. g9u+do47 v (.chhgbrbum horizontal 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 q1w+hdp7xiaa,g8y p+ b* w r9pflatbed of a truck. It is held in place by metal brackets that can exert a maximum horiz,+h ibgwyra7dpp *p+a1xw9 8qontal 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 cab?

  In the Atwood machine shown-s h)zcld heygn05 /mp7j2(ut in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Igno02lcehhnd(p/j g5stym- z)u7re friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kulf rox)o8 u,7g, what is the tension in the string? (Ignore f l7ux)oufr8,oriction and the mass of the pulley.)

  A student pulls a box of books on a stvxjemlmm purmn x9/n3:35g)i;:ul ;i.3 u pq mooth horizontal floor with a force of 100 N in3 r3g 95/ mnlpuv; qe.mpt3nmuu ijxi:;l):mx 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 horizsnl -h1qlig4;o o( btm ip6b38ontal floor with a force of 100 N in a direction of 37.0e above the horizontal. -(b;l1nigohb34m8qto slp 6i 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 weight 100 N is supported by two ropes as shongxrran0o5 3xa ,j axm4z a*:,wn in Fig. 4-2. Wha0axra*ox,ax45:,zj gm r nn 3at are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of thewu ha5+-oklepl:b- 1m traffic m1:- 5lwb ho- l+kuapelight?

  Two boxes of masses m and 2m0jxwn a5-c;h6jjx 9pe are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the m wha 0 ;nepj69xjc5-jxore massive box?

  Two boxes of masses m and 2m are in contact with each other odicb( (*1n16a jhby 4mjng b(kn a frictionless surface. (See Fig. 4-3.) What is the net force on the more massive 1 ( nj1hmyg6abc*b4kn id(b(jbox?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the fxf utrr(uf; yh(-t- c(c42ez (ilmtp+orward force on the c(( t rfc4tm(hu-2t y;ler-i + xupz(fmore massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by .y*5e(tizwjd hp1i b4z5n pd*a rope. (See Fig. 4-4.) If the foin*zy5bhp ( zipjdte.dw4 51 *rward force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected bv cwcbc3 l* gx52j9rv4m.stq8y a cord running over a pulley as shown in Fig. 4-5. Box I of8 c 4 g5bl3vjws .*qcx9vmr2tc 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 box and a desk ;yb;j 823rby/ser;fomt2y ake9x0f j are 0.40 aebs y8x;rtojyf ef9j a2br;2mk ;/0y3nd 0.30, 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 vps)n-0 61es1 8mh-r.)atbkubdjooz:8so tyfor plastic on wood are 0.50 and 0.mjz o 8)-)1snsood0shut1 tp yak.8re6bv- b: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 diren:)x :pf wu(aee0 iz0jvbw:v0mqeb fplp+( 7-ction. It slows and comes to a stop wit xuw b(e: bljv 0qw f0p:vm+fp-)n7iae zp(e:0h a constant 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 is pulled by a 5.0-N forceu8+iu 16 ofhxo4:ikie. A 3.0-N friction force ret efiu6:hioxoui1 +4 8kards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg m 9en8hwgu;tt *)zm jlk1e9d7 aass, 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 initial speed ofsezsm4p :o(+f h0q s4d2zy 0.wd7mydxfy;a,g 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction betweeny;4e zyf0,7 +d.h2 dy az0m4qom fp w(sgxdss: the puck and the ice?

  During the investigati2gbj12meh5x xfzpr( -: tbr1zq wv(0 qon of a traffic accident, 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 for the prevailing cb11wf (e2rm rqgp(05 jzx:zbqxv-h2tonditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m ar o+pe-rs8avk5e 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 5+ -ervo sk8apthe 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 3mb ;r;fj ,m3oim 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 mo;;ro3,bjmm i fre massive box, what is the coefficient of static friction between the boxes?

  An object is on a fricc -e:inm1s;t:7gw vbltionless inclined plane. The plane is inclined at an angle of tl ns:- c:v17;wegmbi$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a 6qcjt ,cs yk-1flat 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 plane withqt;q9bjb3c j:t7orq ; 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 pm8 )crjw+ kkv;w2,vgat 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 const ,jh l urc6xum5l3-nj,ant velocity of mn5llcu3j6rh j -, ,xu6.0 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 co;e4 o6e-wz a:1uzy*lly 9l odown 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 mas2c*lzm+m zk5h s m slides down 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. T d4t;*kdb /o u/qhgb15jxk;txhe cable attached to the log makes 5b/qhgd*x tkx 1 4;d;bjtoku /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 onrol 2jo-g2*k;(wdd gx1gdpb1 a rough inclined plane tilted at an angle ofpd g*w-d1 ogx2 ;lk(br1 og2jd $33.5^{\circ}$ 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 angcw tw*bth oe 0x7wu6ke7u4n1 -le of incline is gradually increased until the objectuxe h0o7w6e wn*k1t47b-ctu w begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?