Which of Newton's laws ec r0qy*r1vw (p9iuf x*st (s32q i6ckbest explains why motorists should buckle-up?

  When you sit on a chair, the resultant fo)9;c.b aviij z.tumub2eb9 -crce on you is

  In the absence of an external force, a,.h)byktzzmtw 27 iz4 moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned off,ttkrmx i5z9f :0:-f vynxyf72 while traveling in empty spkfyr :f970fxtmt iv 2y5nz:x -ace, the starship will

  A rocket moves through empty space in a stjgdv/uohc4+ flq6;57;d9g k ki qq2izraight line with constant speed. It is far from the gravitational effect of any star dvd;qg+ i2 74 cuqk6 /oqk5 jig;9hzlfor 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, facing forward, andgss5).)m:r bidq;d c j you suddenly fall forward. Yoi:bc.j5d;)q ms)g d sru can imply from this that the bus's

  You are standing in a moving bus, ax8/beiy42 7l; jqd*dmd ssb; facing forward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused you to fiba d2q;mb8*d7/;4syj sx eld all forward?

  A constant net force acts on an object. Describe the motion qc 8c-9r rxz 6dij4 lf* 4gem-)nh6tkgof the object.

  The acceleration of an object is inversely proport ,cw:(qdfk e47pat3op6y lm1mional to

  A net force F accelerates a mnvoyc*g*57 runes; 7h ass m with an acceleration a. If the same net force is applied to mass 2m, then the accelera c7*oreunn * ;vsg5hy7tion will be

  A net force F acts on a mass m and produces an acceleration a. What acceler /mm,s(oh)ibojsc* t b (fq)w+ation results if a nes*bsm fw)mo o +h) ji,c/(b(qtt force 2F acts on mass 4m?

  If you blow up a balloon, and then rdbxep utcl;ha6w7 ::,elease it, the balloon will fly away. This is an illush cwb: ;,xpe 6du:al7ttration of

  Two cars collide head-on. At every moment during the collision, kp( zlnf,:il f7) p5y7+wafqgthe magnitude of the force the first car exerts on the second is exactly equal to the mf,+k( qnliw gf)7pal75: fyz pagnitude 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 exertbs5vvn +)d*em s on you wil )svmv d*b5e+nl

  Action-reaction forcm ga,-v/d)5i6y (aktvprz zn4es

  Action-reaction forcesgsk4t)t bavi 82w(:ui are

  A 20-ton truck collides with a 1500-l h ht su+b9uc35lg8o3ib car and causes a lot of damage to the car. Since agb+u sl8h 3c9o h5tui3 lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this object fn f2vfm/b39w- 5edxv pq re-3with forcefrfd -nqwvv-fp9 /e m533 xeb2 mg, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceili6przr(- jou 8ic10+tn sgpadualx (0 /ng 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 "re r80+g udau10lst-pn 6x/apzric(j( oaction force"?

  Your bat hits the ball pitched to you with a 1500-N ppno23 v7lr)r8h;.d orxvgnub05b ,k instantaneous force. The ball hits the bat with an ink;25pgxv7 ud0pbb .orhr,o8 l)nv 3r nstantaneous force, whose magnitude is

State Newton's three lm 8l9*t0 ujovqaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. 7. 0ap.9xinlzt fwku ,qux06s Which of the following is true about the mass and wei.fxi s p9akxw7.z luut,n6q00ght of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a dir+z yv2y +b+tgstance is

  Who has a greater weight to surpr.q28, gfjmh4op8 a35 pkrg)*cs mass ratio, a person weighing 400 N or a person weighing 600 j8 fpcros)qsg5,grpmak4 8u2p3rh *. N?

  A stone is thrown straight up. At the x77baj5k pkfyg +(/t, p 7zkrqtop of its path, the net force acting on it rk p/y+j(pkfqbxtk7 gz5a,7 7is

  A 20-N weight and a 5.0-N weig sh5bdpk9, /xkht are dropped simultaneously from the same height. Ignore air resistance. Compare their acceleratiop 5k9hb dx/sk,ns.

  A brick and a feather fall to the earth at their res+dsk hwlz:bgmt 4g25 2pective terminal velocities. Which object experiences2 4dwmlz:hs5gt kb 2+g the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an ex2w22:rq kziwpq74 qtlevator. The elevator is mo2kq7xr4tqwz :pqw2 2 iving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a w k, tb4o6fm4ztfo 2*vstring from the ceiling of an elevator. The 24o zbktf4tfw6ov *,melevator is moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding ondrk q4p1m,:er an icy sidewalk is

  It's more difficult to b * -fd*pcl6por li,w:start moving a heavy carton from rest than it is to keep pushing it with constan,6 l ropp-:b*fidl *wct velocity, because

  A horizontal force accelerates a box from rest across a horizontal su.kbtdx4p v i7 v+il147b we5azrface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exceptibei.a5+w4p 7lvz bki 14t7vd xon that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined rampp:59 50ha2wtaotmcjiwru usn 5 /n; /u at constant velocity. Thus we can deduce that /naouna:imrhtwu5s w up2095tj /c;5

  A block of mass M slides down a frictionless0vwok.hmh;f,xy(1 e z plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane ov 1wm,y.;hx(z0k heof n the block is

  A block of mass M sl-),cr1-hfqdpv0s6r d wgfzvo, uf9 a)ides down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerte)p cgfqu6 -)vr-rf , svd1z hd9wf0ao,d by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at az 0w4,ch2yj -*l;g +wphb5n2 sk buxdkn angle q with the horizontal. The gravitational forceb4y,0 k -*nu h2 lkgb+x2 z;5pcjswhwd is directed

  Two toy cars (16 kg and 2.0 kg) are released simultane krp3i2od0s h+ously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration dr k0hso2+3pi after being released.

  An object sits on a frictionless surfac0r (:vym4htzhvg.m, de. A 16-N force is applied to the object, and id 4 gv,tzr.m my0hvh:(t accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000ku. 1m33z ot dvw :8tyv.qoou) kg can accelerate from rest to 27 m/s in 7.0 s. What is the avu3 1d)v tm .oo.3uqywot8v :zkerage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s dz*j8 em22s li ,7dys:lle -clin 2.0 s. What is the 8lzs7l-yl c 2 ejlei:d,dsm*2net force acting on the body?

  An antitank weapon fires a 3.00-kg rock04f7dvc*s lbr* cftc3et which acquires a speed of 50.0 m/s after travev*bf 0cc7 f4*r3lcstd 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 force that you push a 10-*xyapbxcx w+p+o y;4*kg mass from re++ ;4*baxyopxp*xcwy st,

  What is the mass of a person who weighs 11rlasz7,)d:)ee ho+g us30s oy0 lb?

  What is the mass of an object that weighs 250 N on3ooy dx9z 6jem3/z*aw the surface of the Earth where the acceleration due to grav3 *z/doem6o 9 jw3axyzity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the k0g(;h 0 9ww z (t3cq0gmgilvamass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 lgkgmwgac 0v;09 w(q zih 3t0(of that on the Earth?

  Object A weighs 40 N on Earth, an i8y izom ssjq94pa:ps7m n;)*d object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's.)z7ss*moamsij984n y ; :qppi Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of emy .dp:;y*kuj u9jml9.xv c-h a /5c-daphq:a 5.0-kg rope. Sue pulls .*mk vj.5e/9m-q hldy;hxupc u cpa9:-yajd: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 restjvjq qont0j g)+3 5c(0lxhz0 xs on a level frictionless surface. A force F acts on the stack, and it accelerate cqz) +nl o5x(3jjv0xj0gq th0s 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 59/ndm. v tfndthe scale be reading when the elen.md /vdf n9t5vator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides ph,ha4erzesf00x10(yb ug 5vin an elevator. If the mass of the person is 60.0 kg and the elevator accelerates downward with an accel4evfy ux bz(g0 p05h1ah0ser, eration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. /82 f 9u3 p2rh*sorwmlc7omnc If the mass of the person is 60.0 kg and the elevator accelerates upward wrm/7hpcw9m2 2nf* 3lusro8 ocith 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 force has a m2*v-h nmiek 37oat qo3n.uvn/agnitude 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 accelerati*k-a73hmo.un no3t vi e/2qvnon of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is hel7sk q ;ubu4l ss d1s 6a7:wdlrd+fla:9d 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 notb:l9sqw :ddsu1k7rud+a 4l 6;l7saf s to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed o8(2ytch/c m9kn bo gs fkar4ga36),fwf 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 time if the load is not to slide y, omr 86)2w / ka(f43htcgnbksg9cfa forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 6(a, oow 9dq ;oce4mht0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of thcqowh 4oate(6d, 9om ;e system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m o9peh:ewle4 ggu; e 7dwsp (13= 0.40 kg, what is thee4l7g ;:h eogswe3w 9(pdpu1e tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a fo) 3: e.qklhd,zr lws*drce of 100 N in a direction.herz dd)kq3ls,w * l: 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 floor wq2w5yc tr 2o+kith a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40cw2kq+or2 5ty.0 kg, what is the normal force on the box?

  A traffic light of wg k4a 0yj3)j(km5w -ys pa6ze hh)rln0eight 100 N is supported by two ropes as shown in Fig. 4-2. What are the tensions in tz hy0ls )mk0aek3n)r4 -6ayhp(j5jwg he ropes?

  In Fig. 4-2, if the qjm*rup 266 hktensions in the ropes are 50 N, what is the mass of the traffic pm2rk6q6 u* jhlight?

  Two boxes of masses m and 2m are in contact with each other on a frictionles i;zd20a6swv+zggxj4 a1t8n gs surface. (See Fig. 4-3.) What is the acceleration of the x +2680jn g1gsiv;a4gzwzdat more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionless sut1m9u,cr al+14lhh1ldmxau) r ) w,tzrface. (See Fig. 4-3.) wxluzr)1 m,, +t taluh l4h)mc119r da What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) 3* jm.9z7eqn zavun6oIf the forward force on the more massive box is F, what is the tensionn9e .zn*3jz7a q mov6u in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See)5p5bi /z srse Fig. 4-4.) If the forward forcbire5s5s/pz) e on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fig. a 5f(; -7.shit *ad7xljezjdk4-5. Box I of 7htzl5.k(ea-dd7;ij * jaxsf 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 de0coet79 hof 7lsk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is appl9fe7t7co l0o hied to the box?

  The coefficients of static and kinetic frictions for plastic o6y/j6 nz,zvn iry8/ t )1pxxfjn wood are 0.50 and 0.40 xn8y jptjzx,r ) fn/61zi6yv/,
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 slowsg86fh4wmk4u kz+-1(x7e oe nruwytw - and comes to a stop with a constaf-+hgnuw4koe t46 8 w7eu1z wmy-(rxknt 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 force. A8 4zjaeh j-dk6 3.0-N friction force retards the motion. j8dz6 jae-h4kWhat is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, aye2(ka1j 9p;d-a niz dt 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 gxjy* b:k0 dxq+iven an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kkxxjby d:q0+* inetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find sk(gjw+ .z4ko ;isw,thsg33zm bid marks 90.0 m long. They determine the coefficient of friction b w.3s+ zj( z;m3 wkg4tsibgoh,etween 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 between a:cab : /x+jimjk*:(zgoghu0 tau. m :the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less massive bu* oijau:mx:a(: 0tghgbjcm.a /z:+ kox 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 arbav1k6rdc 2y/;a( m1 (c cdzhu vls(2ze 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, wb((c d21c;r zu6l a1z2mkc v(/hvyadshat is the coefficient of static friction between the boxes?

  An object is on a fr -h00pdd v3aklb8jbk+o( v 5rqictionless inclined plane. The plane is inclined at an angle of 5 d ld o0bkb3j0vr-vahq+8k(p$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down)-t-/)orwvxb,u tv j b 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 plane with anie4/aa dk wnpz1kv n k sacs4;y-l70f3w:up;, 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 )jvmhy+, o 8htinclined 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 p q t bt(;,h1gds4es ky+b0rm)1cfbkt 2lane, at a constant velocity of 6.0 m/hd +tt,4bf y2e( rskc1b;tsgqb)k10ms.
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 downg :pq2m; ikf-, nw,z )lvw3ukq 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 sli7 oxw3ys/uh /xdes 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.d gsppb8v*(w5 The cable attached to the log makes an ag(5 vw pbp*8dsngle 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 a rough inclixbz fw,t53ptcf(8,m r ned plane tilted at an anglec ,f (,3tb8 wtr5fmpzx 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 inclined plane. T md/r+(wrib +lhe 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 betb+/d( r lrwmi+ween the object and the plane?