Which of Newton's laws br+)twlxn rislxz002 (ri sq:; est explains why motorists should buckle-up?

  When you sit on a chair, thmxld jv .;m3z.e resultant force on you is

  In the absence of an external force, a mov n8eesd5y:b9hing object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN areke0r:b:c+, tamo( fj(s nefg* suddenly turned off, rt( ,amgsfoc: jke( 0+enb* f:while traveling in empty space, the starship will

  A rocket moves through empty space in a straif5 n+g*+;d xq n-;mc 5vtqml /zczx5slght line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applie 5xmf55nn- l+/;v zlxmc+s;qq ztdcg*d to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenly fall forward.; jkti,t)8r dd You can imply from this that the bus'd8)tirk;dt ,j s

  You are standing in a moving bus, facing ruypd(4p f-z; forward, and you suddenly fall forward as the bus comes to an immediate s;4 -pdupzfy(r top. What force caused you to fall forward?

  A constant net force acts on an object. Describe the moti3:6 wsxoin2y bon of the object.

  The acceleration of an object is inversely ls mva5 5l4sr5x ,vv;x5gx:rfproportional to

  A net force F accelerates a mass m with an acceleration a. If the. wa mk4-)vhbc+.agr h same net force is applied to mass-a.)mvhw k a crgb.4+h 2m, then the acceleration will be

  A net force F acts on a mass m and produces an accelerai/zy95su z5rl tion a. What acceleration results if a net force 2F acts o59ur/ 5ys zlzin mass 4m?

  If you blow up a balloon, and the,jht x)fa d 27:eo2oyvn release it, the balloon will fly away. This is an illustration of2dteo yvha:jof27, )x

  Two cars collide head-on. At every moment duir -4k fygt m,+x )js:qjoe/,iring the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnii4 o,,-+ifm rjgj )x ks/tq:eytude of the force the second car exerts on the first. This is an example of

  If you exert a force Fe,-1ck97stbq 0h fscc) 5e0fh1 elfgd on an object, the force which the object exerts on you will s )lcfd f9t h 1,g0s57cehe-1kcebqf0

  Action-reaction forces5ldu/*vqy db uu:a 5k6

  Action-reaction forc12o /o.iq(o pnh.xdqvk) zye 6es are

  A 20-ton truck collides with a 1500-lb car and causes a lot of dama)z 6w cv05oluhge to the car. Since a lot of damageoz)vc0w l5 hu6 is done on the car

  An object of mass m sits on a flat table. The Earth pulls on thio;;fq..np eya s object with force mg, which we will call the action force. ;pqaf. e ;no.yWhat is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The :4p3i0 ;9c 2*floxim epwiw dgqj3hzv65iqd0 Earth pulls do56gi zcid:i9f whi x23e;p 0qv4lqo3 jpw*0mdwnward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitchednq uuns1bur,r /3)y(m eku x7kxn-r .4 to you with a 1500-N instantaneous force. The ball hits the bat wi sn,r3)m -(1n4. /rkrnkuuxequu 7x ybth an instantaneous force, whose magnitude is

State Newton's three l4f rvhc4) q b2xsd3k0xaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on,lo6nw,o bh) x Earth. Which of the following is true about the mass and weight of an astronaut on thehb nol,o xw),6 Moon's surface, compared to Earth?

  An example of a force which acts at xyzrrtr482n dg/yt27 aqf)0g a distance is

  Who has a greater weight 4:galst ravq 2+m3; ugto mass ratio, a person weighing 400 N or a person weigha43gts rl;g: +m aquv2ing 600 N?

  A stone is thrown straight up. At the top of its path, the net force+abo9vinj o:n*a;d j5 g-md e6 acting on itn;d-5d+ab aoimjno* v9 6jg :e is

  A 20-N weight and a 5.0-N weight are y4qo: ihikqyp4 .,-dv dropped simultaneously from the same height. Ignore air resistance. C -piqod q4i. :y4vyk,hompare their accelerations.

  A brick and a feather fall to the earth at their respecyb1f m6kh:r0 ktive terminal velocities. Whicfh ky m1r0k:6bh object experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of zz+q- (ebgvqw*jy; 1v dgm8k+an elevator. The elevator is moving up at constant speed. What is the tension(+ *-gk j;dzyev z8qgmq1w+vb in the string?

  An object of mass m is hanging by a string from the ceiling of y-lpxza5fp*mp4 5 / nsne(*uian elevator. The elevator is moving upward, but slowing dow -f5*/pn p* nmle4 uaspzy(i5xn. What is the tension in the string?

  The force that keeps you from sliding on an icy0y*vo*js iun(w*juzcm6 ; 2iwq/kb5 t sidewalk is

  It's more difficult to start moving a heavy cart n2zhq ojg;tes17s*c,gz;7l8c +pjjron from rest than it is to keep pushingz2l +jjztns,q;h7po r ;e cs gj*7cg81 it with constant velocity, because

  A horizontal force accelerates a box from rest across r ehj37gj6+-mpu b tl-a horizontal surface (friction is present) at a constant rate. The experiment is repe- 6rlmtb-jph3u 7jge+ated, 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 ixp4v .odx(4u3fqa 9ki nclined ramp at constant velocity. Thus we can deduckv4fx d(3o4qaiu.9px e that

  A block of mass M slides down a frictionless plane inclinedsrh f +ts:.(kh at an angle q with the horizontal. The normal reaction force exerted by the plane on h.sh+s(f rk: tthe block is

  A block of mass M slides down a frictionless plane inclined at an anglej 54w8 m( 2wth;-jzvujvrcl f- q with the horizontal. The normal reaction force exertjf5-rz; (v8v2j 4-w mhjt wluced by the plane on the block is directed

  A block of mass M slidevmzs :7jr, /:jnu fa1es down a frictionless plane inclined at an angle q with the horizontal.nr :va e,u/mz7 :j1jfs The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclinra (1p, nlj7bned plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after ben,1 janpb(lr 7ing released.

  An object sits on a frictionless bk527g)u cjv9dsfw x. surface. A 16-N force is applied to the object, and it accelerates 7 bv) 2ju5gfwc k.s9dxat $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in9k.(- jua6 vb f0it)kdijs gc) 7.0 s. What is the average forwar9(f s)b)icukt.0ad 6- ik jgvjd force on the car?

  Starting from rest, a 4.0-kg body reaches a hndhnd v7//uqa+qm 5 4tb(t2mspeed of 8.0 m/s in 2.0 s. What is the net force acting on the bodnd+ h/h q7dvmtaq m54/n (tu2by?

  An antitank weapon fires a 3.00-kg rockeu 4vdk /j)3nzht which acquires a speed of 50.0 m/s aftern3k )zdujv4/h 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 same force that you push a 10-kv+ /pkz1c3o/xue:dwweeo s- ggltq,;9v im2 )g mass from reste e/sti/-):v3e1cug, gmowp qkw ;lzxv+do29,

  What is the mass of a person who weighs 110 l1ok4mw4 n5 eqfb?

  What is the mass of an object that weigzerw-eoe k ;8t.*9n6 (ubxz zlhs 250 N on the surface of the Earth where the acceleration due to gravitk9e *zez(;6z.lb 8eoxr-wntu y is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object0,y2bp, ;modtmo/u mj on the surface of the Mouo0m2pj, ;bt mo/dm,y on where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and oj ,o2 u/ky: c;hbvym4 dwl /p5l5aum-xbject B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of tmyo,julh-:yk5a dpwb x5/v; 2u ml/c4he objects.

  Sue and Sean are having a tuje a0fyv0( o)dg-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pullvy)00( dfajeo s 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 frictionless surface. A force F acts je 3jbpx,am07 h6j c2yon the stack,, e jaxyh2cjbj670pm3 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 elevuk ;mfio -,2ssator. What will the scale be reading whei2fosumsk-; , n the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the peml)+iwje7; 2: remmccrson is 60.0 kg and the elevatm2 7 j ccmm:);irwe+elor 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 mass of the person iym wxbns,*( i6 ;rbmm9s 60.0 kg and the elevator accelerates upwims b*;mw(,br9nx 6ym ard with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forcer1j vji 1n .*gu/x)hqls act on a 5.0-kg mass. 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 acceleration of the masqg* r1iju/.1xjl hvn) s?

  An object of mass 6000 kg rests on the fiqqwc5+r0 -nflatbed 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 the minimum stopping distance if the load is not to slide forwarn0w 5qqicfr-+d into the cab?

  An object of mass 6000 kg rests on the flatbed of hi 737hdwuswo);ha ft9n7*b va truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck isas i37u) vf7*od ;w7hh bnw9th 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.sk. zv8d- :o;s (gfhsm60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction s(vgh om.;8-dksz:s f and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 z) vnuo piwx-/dlg27:j 2+mxbkg, what is the tension in the string? (Ignore friction and the mass of the pullelj+ wb:im-do/xnpu z2 7xv) g2y.)

  A student pulls a box of books on:djl,i m 2r3baoo/n,a a smooth horizontal floor with a force of 100 N in a direction of :,/23noadj,rli a m bo$37^{\circ}$ 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 62ya).5 jtr pjtqsb1h floor with a force of 100 N in a direction of 37.0e2 .rjh)b t6p1sa 5tjyq above the horizontal. 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 weigw v;wf1 ucnx-2ht 100 N is supported by two ropes as shown in Fig. 4-2. What are the tensions in the wv;wxcu-f2n 1ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, h :-mn7es5 tfewhat is the mass of the traffic lig efmhe-75tn: sht?

  Two boxes of masses m and 2m are in contact with each other on a friction; /tm p.iyoxqb:oy; v4ee.8rpless surface. (See Fig. 4-3.) What is the acceleration of the more massive bmipr.4/ y o.oetybqev 8:x;p; ox?

  Two boxes of masses m and 2m are inn8s2z hr;-aw/9wnrmg7v(nmd w9vt n6 contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net fo(n9;d vng6 n8z72svwnwrh a9 trw/-mmrce on the more massive box?

  Two boxes of masses m andu.+mgm nsp( h8 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the connectgsn. hmm8pu(+ing rope?

  Two boxes of masses m and 2m are connectl(-xl(,xs 7sk okmo7x ed by a rope. (See Fig. 4-4.) If the forward force on tko,7 xxmll7(ks-o x (she more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a q+,9p bgj9qk:k .rdru cord running over a pulley as shown in Fig. 4-5. Boxukj,q.kb p g:q9dr+ r9 I of 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 stat1k u f9dz6li8yifa --bdrh m9..o3sknic and kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on t lm-foi.-hkz b9sd dnury. 6af 81ik39he box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50g5di1qxlxg 6p lf.oda*;dk /: and 0.406 d;* ag pxl1./kq5il :goxdfd,
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 direcg,ba+) :by2:cwtytui9tgl: jtion. It slows and comes to a stop with a constant acceleratitt+tl :29wcu:jb gby,iy: a )gon 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 horizoi* ajw ly7w6 xjas7dz*0hi;f5ntal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of the objeclyx h6fdji*7*sw w ;z07a5jait?

  A horizontal force of 5.0 N ak8xzt v,8x74 vrfka t1ccelerates 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 pubpktz *p 8*tzw-wa8r+ck is given an initial speed of 10 m/s. It slides 50 m on the ice before wtb+* *rp ka-pz8w8zt it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of d,y ;0sutd eo5a traffic accident, police find skid marks 90.0 m long. They determine the coefficient of fd;uty5s 0o,ed riction 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 Fig. 4-6.) The surface betwlb1yn :b6q8seeen the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If tlbeq1 6s b:ny8he 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 m2bb*vyrbx.i+6q- i oynz + u5g and 3m are stacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface betw*.ryuqbynx 52 b+ v6-izo+ibgeen 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 plaa3 f1bbnow 9o,ne is inclined at an angle o nbobf,oa3w1 9f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makesax:1lhfs7nsph8/ 6t+0f0z l tzg wq i8 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 with angx qmgx2tv(86gyz8 e- 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 .j9imbho yx- /ucfig: /.zn+wat 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 ui1psqdz 1b+ ph w(6q,t3b*v ebw:nj- plane, at a constant velocity ofep6duw:1whn*i3b bb+ j q pvq-s(z ,t1 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 m slides dowx:l au. 4ff,,hmq 8kiu91b s*gda2fk gn 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 jx8 do2;dwp-k 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 wes -lgz fm,hq94ighing 500 N along a rough surface. The cable attached to the log fgm ,l9q z4sh-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 f)4adzmx hyy,0rom rest on a rough inclined plane tilted at an angle of ym )4yh,0 dazx$33.5^{\circ}$ 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 of io dx.;cw05fj vncline is gradually increased until the object begins to slide. The angle at which this occurs is5j 0wf.cv xo;d q. What is the coefficient of static friction between the object and the plane?