Which of Newton's laws bebobs,vpgz, g7:.+ v* yhlc )ejst explains why motorists should buckle-up?

  When you sit on a chair, the resultant force on you isklr ;8-*c j garuwp:x 7eo9y7z

  In the absence of an external force, 1hob)x niv,0jn rsl28 a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN ar 1yp :r(mqm .i2;fllw7kw3:pdrz( gree suddenly turned off, while traveling ekr21 i mdyw3: 7;r rfm.:gwlppqz ((lin empty space, the starship will

  A rocket moves through em5e,nb4u+d3scp ltz (apty space in a straight line with constant speed. It is (a ,le 3pdbtz5cu4s+nfar 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 its motion is

  You are standing in a moving bus, fac )3wj))h p4 sgv9 5lybv4k-eqlgd nyy8ing forward, and you suddenly fall forward. You can imply fropd 5vyyyj9 kll)-4b 8gvw3 ns 4h)q)gem this that the bus's

  You are standing in a moving bus, fac 2bq-e(5zju h0xzlg:ring forward, and you suddenly fall forward as the bus comes to an imm:b- qzr ju l0gz5h(x2eediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe td 3zt-dtim 8+xhe motion of the object.

  The acceleration of an object is ian51mc8k fnv 3i, ;dlhnversely proportional to

  A net force F accelerates a mass m with an acceleration a. Ifgvcr:b b:sxn1b6fzj0 fb-8* f the same net force is applied t1rfx: *b6zs:0nbb- fc fb8gvjo mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an 2k(xr tel h1b ua: dh8vvkve: e;414reacceleration a. What acceleration results ib8 e ;a:1hdhk2(rke4uvetx 1vvr4: lef a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloonlrfr0.,pt p( n 9tuy (bed/8fga402:i nbqxje will fly away. This is e4 l80.f2pp r(ynu q:bdf/jantg ( i0t9b x,eran illustration of

  Two cars collide head-on. At every moment du,-n qgdhe0n :)jecy, rq3 moz8ring 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 ism)j qgcehn, q: ,0 dory3z-8en an example of

  If you exert a force F on an object, the force which the object exerts ovrg 9kt1 k3 rjb 5 xw;pfha43+g-6yyjtn you wilyk 5 b9 ggt33xjatv+j-1rfpy hw;kr 46l

  Action-reaction force96uvju nf7 b5ys

  Action-reaction forces are0rjc jnjmtf +j97-bd2

  A 20-ton truck collides with a 1500-lb car and causes a lot of damagev 6m6u7 5sdsz+2wt7ba-(ui9 ry ansq y to the car. Since a qw manstd i6uyb v7r5-uaz2s69+ys (7lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this objecca 03/p j ,se++3a/zf gebbcyvh1 em1nt with force mg, which we will call the action forc 1hb+psafz+ mncebj,13ega// 3y0cv ee. What is the reaction force?

  A child's toy is suspendedcwo -,csxrw6:l;ga/ 19i pkmh from 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 force," what is the "rea-c 9owr,6:;mas/kwp lc gihx1ction force"?

  Your bat hits the ball pitched to you with a xg)dn5 f(niuka6/v91 r hdk-nrnq + 1g1500-N instantaneous force. The ball hits the bat with hn+vi1ng6ku /qd kga9(x-)d f5nr r n1an instantaneous force, whose magnitude is

State Newton's three lapp27fxetn5vdd5c0s )vr w f53ws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than oe;d)7co epv qsm;1b2 ate3l g3n Earth. Which of the following is true about the mass and weight of an astronaut pee;oatslg)b e3m217c 3vq;d on the Moon's surface, compared to Earth?

  An example of a force wsbd hp + -m,r ph+na1)wjam(e7hich acts at a distance is

  Who has a greater weight to mass ratio,vk50* 1lb1wtn *nwdgx a person weighing 400 N or a person weighn1 xwl5 *k0bwtvg*1n ding 600 N?

  A stone is thrown straight up. At the top of its path, the np;w xmv)m;7 /j.s/ -d.xop7niabewd fet force acting on n-/7e ).xx/mwd;vf; po7ibdsm wp .ajit is

  A 20-N weight and a 5.0-N weight are d.mh1bvi1 4k nlropped simultaneously from the same height. Ignore airk 1v.hi4 b1mln resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective te5wa (9wl0mrq6nbll 7 prminal velocities. Wh (9nlb arwp m0q6l57lwich object experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceilingk+. prvxx,g.bjd8 u 3k- y4bci of an elevator. The elevator is moving up at constant speed. What is the tension in the strijybv3dg x.-pbi.x+ cu 4krk 8,ng?

  An object of mass m is hanging by a string from the ceiling of an elevator1)miiv sku)l )sy+a d8. The elevator is moving upward, but slowingsid+k)) lisma)u8 yv1 down. What is the tension in the string?

  The force that keeps you from slizof ly9ti7e: us lc(r/1 3ldm0hpj (d+ding on an icy sidewalk is

  It's more difficult to start moving a hea, p blj +gl:9tdgv06pkvy carton from rest than it is to keep tlpvk9bp:gg+6, 0 jldpushing it with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal 92 ,,fsc78tsg lmqz b) f2wksfsurface (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. 2ffk8,)cswg7zf9 qs,l tm sb2 What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Tf*:wjb(+e ma ihus we can dedj+aewbf m: (*iuce that

  A block of mass M slides down bc;3kvt ;zo0 p b5h o+/wu7zqda frictionless plane inclined at an angle q with the horizontal. The ozdc;tvqhb3zp0w5 7+b/uko;normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an anglk;ee( pxxv7tu +7p+cme q with the horizontal. The m7;e++ek p (pv 7tcxuxnormal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane incline vlem36odrxy6u/ n/qzfiucx,r/ 4f-1d at an angle q with the horizontal. The gravitational force is directedyu cnz x4-mqx / rv /o36uif/6,rl1edf

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclinei 6g-tx1qg p (aj4yo9hd plane that makes an angle of 30e with the horizontaxhq4gt-gj1 pi ao(9y6l. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is tnr hf10p5c .i+.uyue applied to the object, and it ac5ph 0eu ufy.n1ir t+.ccelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acceleyk mq3i;g 5wfavi j:d2h -jl7r;m ja(/rate from rest to 27 m/s in 7.0 s. What is the average fk73 faql ji(;j5-2rgw : /;jdm vyimhaorward force on the car?

  Starting from rest, a 4.0-kg body reaccnehy ji// jj.sdl.yjs8-w93 hes a speed of 8.0 m/s in 2.0 s. What is the net forcenjhl8cwdss ./ -e9 3ijj/yjy. acting on the body?

  An antitank weapon fires a 3s/lc h)6sm7-ob ht ji;gv2q 5l.00-kg rocket which acquires a speed of 50.0 m/s after travel/ ;6lts)sjb gv2h 5qlimh-o7c ing
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 masshlt ,g1fuww 91 with the same force that you push a 10-kg mass from restwl 1thg1fw,9u ,

  What is the mass of a person who weighs 110 p; in8q4s+js 0xlfq(p lb?

  What is the mass of asr/;k ga j-n2zn object that weighs 250 N on the surface of the Earth where the accelers;z- njg /2arkation due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass oko-)6( , 7 bzmd:qx cgm+datryf the object on the surface of the Moon where the acceleration due to gravity is ongo rmm+y6) ,7 -dk:cz b(xqatdly 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. pdk ai(4l+*; ut/dtweThe Moon's gravity is one sixth of Earth's. Compare the masses of the o(/d u;t* wlp eidtk+a4bjects.

  Sue and Sean are having a tug-of-war by pye*do/c2 ab-e9n1, bdigh +houlling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-gy/ehn o9 d-1ibd,h+eca 2ob*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 foron0rca g ya(ay;rzm9 )kuoy,c c),d/7ce F acts on the stack, and it accelerateoa a (mc9n;cyykrr uzd,0/ao),)yg c7s 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 tqc/ fhflm2 ;-h) : kzgv nt*(gkea)34uxlz*sthe scale be readin:2 h4h/l*)3s-al*g k)zk xfngcmeuv (zt;tqfg when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale r(k(o4qnvkoxv1 ,m7 o8px a9bee8jcr 0ides in an elevator. If the mass of the person is 60.0 kg and the elevator ace4oekq 8vcxra1,79 p8x moov j(nk0( bcelerates 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. lts*g ;ryf a,5 If the mass of the person is 60.0 kg andt gfrals*y5, ; the elevator accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces bggt. :6 c-d oag7h)msact on a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force towgm:7 g- 6 ohcbdgsa).tard 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 e7 ajxw* q4emr x8hf4;6yo 4raa truck. It is held in place by metal brackets that can exert rwj6xy*x7o4ham e4re 4 8qf a;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 forward into the cab?

  An object of mass 6000 kg rests on th j3hlzuwmh)d .if,(p 1e flatbed of a truck. It is held in place by metal brackets that can exert a maxi uzi3 wpmj.,dl)1f(hhmum horizontal 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 in F 4a- 0vuzmeu mm9qc5;oig. 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 mv0c5zm;q 9oueu- a4 mmass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if Mhoz8-+p +jou s = 0.60 kg and m = 0.40 kg, what isoh s+8-puz +jo the tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor witu4doxu6 ps1x +h a force of 100 N in a dirxd s61p4+ ouxuection 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 f)a d2x*otqqp 2:m nf)lloor with a force of 100 N in a direction of 37.0e above the horizontal. If the )2nl)2adx*f t:pmqq o 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 rl.l00o4y irfyr:b o50i(iny+ )m egv0as uel (opes as shown in Fig. 4-2. What are the tenoa on)0er u: (0yvm.f0e4 s0lbrii5glly y(i+sions in the ropes?

  In Fig. 4-2, if the tensionsap9)9 zkzn 2qn in the ropes are 50 N, what is the mass of the traffa)q pzk2n zn99ic light?

  Two boxes of masses m and 2m are in contact with each other on a frictionlo7t*: h (at2 ip/zukbyess surface. (See Fig. 4-3.) What is the acceleration pa o2t(b 7/*kth :zuyiof the more massive box?

  Two boxes of masses m and 2m are kb2;epf /ai ne c 2zof)-:.wdgin contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force ee)a-;n2c: piw.zd2fgob/kf on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (;3 2kaqc) 1x/pxdnh1kuovca: s w7q 9zSee Fig. 4-4.) If the forward force on the more massive box is F,ndops1/ qaqx79x)u;2h1a3:kw k c czv what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope.7,;fbair d,q8,n u)ukw toj+ h (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration ofw)uqn,ah+f, t;kj bo,u8i7dr the less massive box?

Two boxes are connected by a cord run,r+vjo fuh9c m5q/ +pyning over a pulley as shown in Fig. 4-5. Box I of masschf5 v/qmrjop +9,uy+
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 7jcnld(/ gs4 d;e fu(ndesk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizu sd (/f74ncel;djn( gontal force is applied to the box?

  The coefficients of static and kinetic fri jhkd,x gnb-,w 6n7tj)ctions for plastic on wood are 0.50 and 0.40,7 jjntg)-x, hn6 bkdw,
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 direction. It slow v(g4 og.mj+ v3 pzp:00mfgutms and comes to a stop witm3pm o pm.0g+v0(zujfg g4 v:th 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 f7 h zaup43o(5va4x fv9d 8lux81dcfch orce. A 3.0-N friction force retards the motion. What is the acceleration of the obje3acd1dxuvhfa8vz4 ulx of5hc8 4(p79ct?

  A horizontal force of 5.0 N accelerat: r9cl eq7ts/3+naxrses 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 initial speed of 10 m/s. It slides 5.mdu5i tzq1 +h0 m on the ice before it stops. What zuh 5mq it+d1.is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find wzi;w05vhal b qjps ) ggsp m+5yhe9;q3-fm61skid 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 conditions. Estimate the speed of the car when the brakesbag3lw+ -9h f;qmpeg v sm0zw qjy;56)i5h1ps were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The e3g+f wf sd u,j;/iw0jsurface between the more massive box and the horizontal surface is sm 3;usf /gw,wi0+dfjejooth 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 the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. jxuh k52r(u a x1sqr0397m ghp4-6.) 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 bsr9h(3 p5a1 x0h jg2xru7kq muoxes?

  An object is on a frictionless inclined plane. 1dq:v8.r 6 jofs hl ,youyi52oye 2b) cxr0r(y The plane is inclined at an angle ofb i5v.8r ju :coyfs)rxq 216y,lyod ho2e(r0y $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill thr)7l ..(r3/gy26 cpkfwxqj f ;dkjiq tat 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 wi3otoq)k h w-.sth 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 tillttwbe79niy5rq; snkqpkt3t*e2bl)7 )*y b5 ted 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 ajx :mk q*+uqy7f2-maa constant velocity of 6.0 m-q72x: jq fay ukmma*+/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 slido -qnex.o,u9 bes 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 a rf0qh2ja5f-s r ough $37^{\circ}$ 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 weigoys c9-mgp.6t hing 500 N along a rough surface. The cable attached to the log makes an cp.os6-9 y gmtangle 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 fromgg+ qt09nm xrsi-6wmy x0;a2r rest on a rough inclined plane tilted at an anglemx2rwrg+ ;0 a69i mxq0-y gsnt 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 inclit1ie9a i 7e*vdned 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 the object andi 1a*ev9dt7ie the plane?