Which of Newton's laws best explains why motorists shoumh(-7 sir e3br kv68vxld buckle-up?

  When you sit on a chair, the resultant force on you ises hv rj( 7rgiee)3i6-

  In the absence of an external ford po* f0uk7,fmce, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly wtggci q5: ry56/xap*turned off, while traveling in empty space, the star* 5pqw 6:iaxgy/rgct5ship will

  A rocket moves through empty spazf3 zcjh7 d6zkk 56fk7ce in a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the fkz6f ch7z 6jk5fzd3k7orce that must be applied to the rocket in order to sustain its motion is

  You are standing in a mo4 lrv1k2niz 8xving bus, facing forward, and you suddenly fall forward. You can imply from this that r24nxvlk1z8i the bus's

  You are standing in a moving bus, facing 0spv b sysux63df.w:6 t0u+cuforward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused you d6y30fvu:cwtss ub. p 6xu0s+to fall forward?

  A constant net force acts on an object. Describe the mo (0mkpsn(.s-uba gwt3 tion of the object.

  The acceleration of an cy, jt n ubpc39n--fxl7679 dxb -qvrnobject is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the ssh*5.-5xmu 9xij rxtoame net force is applied to mass 2m, then the acceleraio9u x h5xr.5-j*s mtxtion will be

  A net force F acts on a mass m and produces an accelerp.yz-bsgi ykj2 t12my x 9ou16ation a. What acceleration results if a 1ykyy12 9g.2mbx ou6 -its pzjnet force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. Thisbxm q( wfyq1//ak:dg2 is an illustrk f/qx: my2bwqa(gd 1/ation of

  Two cars collide head-on. At every moment during the collision,uhu ihd(t .q,cc87li6 the magnitude of the force ,8 lc.6h7dh(c tuuqiithe first car exerts on the second is exactly equal to the magnitude of the 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 the object e6+oucs ofjonsg ,x153 2+gxpjxerts on you wi+uxc no2 ogp, ss3jf+56o1 xgjll

  Action-reaction forcei:wl;kzz 9v2 vs

  Action-reaction forces areo6dosfz+jo , f4o -yulb/hw*/ .gpg +f

  A 20-ton truck collides with a 1500-lb co .).tz0 nbrb8fv4rz var and causes a lot of damage to the car. f r)8b0n z.4or.tbzvv Since a lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this objo8e 0; mqgi8mbegm+5kect with force mg, which we will call the action force. What is the reacti0+g8 qe i5kgem bo8m;mon force?

  A child's toy is suspended from theai rmq8,uhp +ztv359d ceiling by means of a string. The Earth pulls downward onhi+zvu8a 9q p d,3rmt5 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 pitched to you with a 1500-N instantaneothz89+h rhpl yg;j:hqle.s. : us force. The ball hits the bat with an instantaneous force, wh ryhe8h.glp.:jtslh:z9+ ;qhose magnitude is

State Newton's three laws /joolb0+.z0 nyglt1ungo,b(t91ez z.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which oflome j+n.gwn+l.vgt 5 ;t:t w; the following is true about the mass and weight of atnjgmw: ;lw5 .v +.lgn+ ott;en astronaut on the Moon's surface, compared to Earth?

  An example of a forcej8v l0i p8.+;h- e 2uyjvzknis which acts at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a p-00pg*/c p:gcvltuqbzk6p t)oyc u20erson weighipbtu2-:cvz c 06cg/0gy* lqotu)pk p0ng 600 N?

  A stone is thrown straight up. At the top of ity/oolj jn++(j s path, the net force acting on itjo nl y/o+j+(j is

  A 20-N weight and a 5.0-N weig q*o 5cg z.-b5f 7zsj5bdpauz4ht are dropped simultaneously from the same height. Ignore 5 u475pszazc -b5 bqd.jzg o*fair resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respectivee7+sfli:h (psutoa,: terminal velocities. Which object experiences the ti:oh ,7a( s:e+lspfugreater force of air friction?

  An object of mass m is hanging by a string from the ceiling o7nl,c23 n5cy zzwn,qff an elevator. The elevator is moving up at constant speed. What is the tensio5z 3zlfc,yn 7cw 2n,qnn in the string?

  An object of mass m is hanging by .8 3yhvlaig ylar 8c .h(wx6t:a string from the ceiling of an elevator. The elevator is moving upward, but slowinyv (hc g.8i.a6 h8llt3a yxwr:g down. What is the tension in the string?

  The force that keeps you fros1urg)bjizzx 8 325gtm sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than i ;v)6z7uba1l mjd .i;w n e9 z.p1ye(nzxp(jldt is to keep pushing it with conj. lxlnz;u( nbz(d1mwv6 1)9; dze. pe7iyjpastant velocity, because

  A horizontal force accelerates a box from fzd-x6til6,o+ /euum rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and/lo6ud - zu6m xi+fte, 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 inclined ramp at con. 0rdp9 suna5nstant velocity. Thus we can deduce th5u. a9rdspn n0at

  A block of mass M slides down a frictionless plane inclcfrr8izdk f7c n;d733 ined at an angle q with the horizontal. The normal reaction force exerted by the plane on zdrnf k;c dri733 7cf8the block is

  A block of mass M slrwu ) z0c hz0dab(4kk2ides down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the blk4a 0z0)(uc zwh2bkrdock is directed

  A block of mass M slides down a friy3i8;xn / ju/yw oddfrfu 2p9q91kk8wctionless plane inclined at an angle q with the horizontal. The gravitational forfd8 9ofji8qkuyd/1up ; wr 3w n2/9xykce is directed

  Two toy cars (16 kg and 2.0 kg) are released simul2sur otr *7zy:v,5afbtaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statoarvf:s 2rt, y7*uz b5ement which best describes their acceleration after being released.

  An object sits on a frictionless sur9 +friw2d oh*vface. A 16-N force is applied to the object, and it accelerates wri92dhf+v o*at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rxtq 27tsx-0)h 0entmbm1l 0ziest to 27 m/s in 7.0 s. What is the average forwat th00ziqbxmtme0l2) sn7x-1 rd force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 sd6k4vu r9) xr.y9ozpm. What is the net force acting k9.mo4 urzp9rxv )6ydon the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a8a4vr/dyxf,ku; m 4jb speed of 50.0 m/s after travelind;xy4, vubr8jaf/km4 g
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 ( +ep :6v1e imljj1sh5kbt4 cqpush a 10-kg mass from rest letjv i+ 6psb4q1jm1(h:5 cke,

  What is the mass of a persuzs.ymgt gq,fh3a h67 fq -8+oon who weighs 110 lb?

  What is the mass of an object that weighs 25jwf*3q q252g,uudj3pgh: pf r.e6 h fo0 N on the surface of the Earth where theo35 2qjuf2 ghdq.,gf*wp:fh 6r 3p eju acceleration due 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 a *gyfct7 . dt7do8p*bj5*lq gobject on the surface of the Moon where the a *b .tfql*ytopd8djg775g*c 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. The q8b: *p dm4m0lslz 4rtMoon's gravity is one sixth of Earth's. C: pmqrms04tdl84lb* zompare the masses of the objects.

  Sue and Sean are having a : wf(v4q acr:cjo.8x)x7mb s:zjbv 2rtug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the 7xv.2vx4m)cb8 bra:js:c :oz qj (fwrrope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests,r9 uxg h9 p4u4i j)abld4pbt; on a level frictionless surface. A force F acts on the stack, and it accelera jlpdrb u,x9gi; )h9up 4t4b4ates 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 the s-qwj,m ci;ez9no jj *5cale be reading when the elevator is accelerating downwar9;,- *5cqjewjzojn mid at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60cjew 7:)zxuldax g1 3(.0 kg and the elevator ac ja u71d g:xlc)ez3wx(celerates 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 is 60.jbw aj(2ehv: 3c9z1qd0 kg and the elevator acceb13 ajejv9hcw2d z: q(lerates 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. One forb8gy1i vf e8a,ce 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 is8yvb,ef18 ai g the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in pi+hhsc, 5cqfr8y+v a- 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 stopping distance if the load is not to slide forward into c+vyqari- +h,5 hs8cfthe cab?

  An object of mass 6000 kg rests on the flatbed o rr lbc1yugqjpb *-7g7kc6;a5 f a truck. It is held in place by metal brackets that can exert a maximu1 pjrbyrl k6 5a-cq*u7gb;7cg m 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 showp fi1 ab yp3oe,qd*o)*vo:-r bn in Fig. 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 mass*aveoq:d 3b1-y oof)pprb ,*i of the pulley.)

  In the Atwood machine shownjcu. x-im1,o n in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what isc.jx oi ,1-nmu the tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal f5vpvq1r60trv +r7 acw6uk:qe5(yopm loor with a force of 100 Nyqacw+rqm p k1v p6 6otuv(e:rv75 05r in 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 flooj8h6s;p0 c8t m5swcybg n+sy8r with a force of 100 ss0p cybswct5h8j; y+mn8 8g6N in a direction of 37.0e 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 weight 100 N is supported by two ropes as vi:f9.kc)m zb3g kon 8r9eo6+f:aui n shown in Fig. 4-2. What are the ten.akungbf o+o vie:k f83mi):69r c9 nzsions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 70mkqh+hpuidp1v2c9if r/ )cN, what is the mass of the traffic li/c9f7v2i d +cphqk )p1hui0 rmght?

  Two boxes of masses m and 2m p2enzbtd +b y2( z*z)1;qnv neare in contact with each other on a frictionless surf+vn )bz(bz;enp*2 nzydtqe 2 1ace. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frye5l 2oet*ahyp-mz +1 ictionless surface. (See Fig. 4-3.) What is the ne -yea1l+oy*25 mphtzet force on the more massive box?

  Two boxes of masses m and fnnv6ytl0 t.r6io q3vn /y0(n2m 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 t(3t yn nq0r6fno0iv/vt.ny6lhe connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fq7;jsva8 ikp 9r,e:7jwzgr+ lig. 4-4.) If the forward force on the mokjwel s,:9ja77rz prqg+ ;8 vire massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a perjlemb)lr r.; b9:r;pxed/7kuj8 t,ulley as shown in Fig. 4-5. Box I of jll /e:dx);jum rr pb r,r8teb.ke9;7mass
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 sta j8 :cdzi g9usptpxq.s354g y:tic and kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, res.gd ups84ji9scyg tq3zx::5ppectively. 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 fo kf*st gwz(7+wur 1gsfw 20bwd o005usr plastic on wood are 0.50 and 0.40,5ogbts0z 1sk+wfus(0w* w7 20 urfdg w
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 d qd ocrfg:3g*+gsrs5yi ,94 tsurface in the +x direction. It slows and comes to a stop with a constant accelriy 3 o5d c4rsfg*dtqs: 9g,g+eration 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 force. A 3..0p y;o1fn iui0-N friction force retards the motion. What is the acceleratio;.i yp 0ifuon1n of the object?

  A horizontal force of 5.0 N aq2a e4,wkt tc lgx**n3ccelerates 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 slkkppi8he+1m cz/q( *p(q36vc; z jf mjides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck andih1f (6epqqk;*+zzj vm/ mj kp(c8p3c the ice?

  During the investigation of a traffic accident, police find*xfx)hb ,bvqook)yn 29j yp se,:pp92 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 conditions. Estimate the speeyev2h2fxbo* q )b)s:x 9 y,poknp,pj9 d of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surfa ,xho)geda2)g ce 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 mag))d2, ohxgae ssive box, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stackw7 8)hsriop1 aed. (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 8aw1ih7o)ps rthe more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless ml /sv 3qp4nkor9jgy4;yh.v - inclined plane. The plane is inclined at an angleo j 9r;v4 vpqslghn m/yky34-. of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill 2 g d4ut5,o ,9v)6oggn mkteztthat 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 smootmn2+n4 0igv2elic+ ,s08fm -zg tvnlh h inclined plane 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 inclined plane tilted at an angv.psu0.:j/ otdk qm e-eu8pj) le 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, atfphq ), af ynix s,.wl)9(zw;i a constant velocity of p))xwy iaw if.h, zn(,q s9f;l6.0 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 dow).ilx-cg 5siln 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 (8rtal88s zrk $37^{\circ}$ 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 weighingqynq2o8* 4fr v 500 N along a rough surface. The cable attached to thev2r yfq 8n4*qo log 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 from rest on7mrltvi / 6q-w a rough inclined plane tilted at an angle ofr6 i /wlt-mvq7 $33.5^{\circ}$ 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. tul6 :fqn,j5kThe angle of incline is gradually inctlq5nk: 6jf,ureased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?