Which of Newton's laws best explains why motorists should buckle7f/pa u6r8 kwh-up?

  When you sit on a chair, the resultank9/i1h 4slv0 msr:n swt force on you is

  In the absence of an external force, a moving oqmfq q*ox/rkk4tal7 l-r 65u5 bject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenl7x hjtj d9ip4a )n) *g8rzawg9y turned off, wh )7xt jph id89 9agagn)r*zjw4ile traveling in empty space, the starship will

  A rocket moves through empty space in a straight :a4 o r ac(88irvbw9xrline with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocker8 9: w4ava8x(cribo rt in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenly f :i tv nuq701 j+qhpe(sfkgg.6k9r1lpall forward. You cann1k.vp9+s6it h j0gpr :qg1(flk7 equ imply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenlyl2kym3p e1y n1 mbix9r:vtz1, fall forward as the bus2n t:19y pby,ie l3r1z1xmmv k comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe*/ez/kx (mvhns x7wz 6 the motion of the object.

  The acceleration of an object is inversely proportio)oakho1 49e :kd uqx1znal to

  A net force F accelerates a mass m with an acceleration a. If the same neyqyimb9t23 r1o8 qtc2 t force is applied to mass 2m, then t3 2 oq2ryiyc81tq9bmthe acceleration will be

  A net force F acts on a mass m and prtg1n7s7fiukc rd1w510q gmq* oduces an acceleration a. What acceleration results if a net force 2F acts onqm 5is*7cw7urg01 1tfqd k 1ng mass 4m?

  If you blow up a balloon, and then release it, fjx0ub.nirb u+4 4( hfme -2+q7hih5zv-ujfl the balloon will fly away. This is an illustration o7fujfui5m+x 4beq z .hf(h-+jhvl4n0u - r2ibf

  Two cars collide head-on.dpi mf,4v+ uubnnj59 *(tc3 bt At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to the magnitude of the force tbi vm3j( b9,unptd*5n4uf tc+he 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 efoy-a8wv , t6uxerts on you wil6vu,o8w ayft-l

  Action-reaction forc.xx(ztwiw wf ./v- gre4h73rles

  Action-reaction forces are v6,l: vg3qg fmo,dy+v

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage tofug6sk hbfl03lf+h( :97a krv the car. Since a lot of damage is h(+fk0 f39fha :kb7sulvg lr6done on the car

  An object of mass m sit5 aqh 8rsfh rm.i,ks8hq/.k.oeu a; bwk9.cn-s on a flat table. The Earth pulls on this object with force mg, which we will call the action force. Wh/ omkhak9f.c8bs,8sq. hqre 5h;w..uak-rniat is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The E )g;veopbbz18arth pulls downward on the toy with its weight force of;b8vp g )eo1bz 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 instantaneous force3ebq8m7 ; hm92r 9dxgtd0kmde. The ball hidgr93m;mq 7 2dx9 mtd0ke ebh8ts the bat with an instantaneous force, whose magnitude is

State Newton's three lhm-3ia91wo0osm dje j4n.e 7,a ctc q3aws.

  Mass and weight

  The acceleration due to gravity is eyg-m sh,dsf6b(.ew 5 lower on the Moon than on Earth. Which of the following is true about the mass and weight of a m-fgd,(b5seh6. s yewn astronaut on the Moon's surface, compared to Earth?

  An example of a force which acvhcaes-z * ;grj: 6-jinlhc4 5ts at a distance is

  Who has a greater weight to mass ratio, aps9xc/i j*fct3a3t0 u person weighing 400 N or a person weighingsu* t/j0paxtc3c 9i3f 600 N?

  A stone is thrown straight up. At the top of its path, the net force acting 9he *po7zl oy-upex)7+zy c1h on it i-1hzzy7hu p)ep *7eo9l+c ox ys

  A 20-N weight and a 5.0-N weight are dropped simultaneogy;3zjd xlgg(z62 b 5xusly from the same height. Ignore air resistance. Compare thjz(dzg6xgy b;x g32l 5eir accelerations.

  A brick and a feather fall to the earth at their respe ew0l:( fkkwvdj 0sgj)q7e5 y:ctive terminal velocities. Which object experiences the greater forcy 5:e0lw)(0 j v7dg sfq:ewjkke of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. 1 pxa:lp 7n4kspgg2- kThe elevator is moving up at constant speed. Whapn p k-ap7:24g lsgx1kt is the tension in the string?

  An object of mass m is han;9 r8q7uyevtct0m w9pging by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tensiu0qyp8w ev rt99mct7; on in the string?

  The force that keeps you fro3-sq -srkss8km sliding on an icy sidewalk is

  It's more difficult to start movinge a6 x p 5n*)6wo9 gcyhqs:2*vs+efhlq a heavy carton from rest than it is to keep pushing it with constant y2pf +l w cos5a*q *):veh9hg66esxqnvelocity, because

  A horizontal force accelerates a box from rest across a horizontal surfajl.t9l0 +pf ntq2pd:oce (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 the btpold :f20.lt+qnj9 pox's acceleration?

  A packing crate slides down an inclined icx3j.s v+o)s ramp at constant velocity. Thus we can dedus)c+x v.3jio sce that

  A block of mass M slides down a frictionless plane inc-l ei+kbf /f*slined at an angle q with the horizontal. The normal reaction force ef+/b ls-fke i*xerted by the plane on the block is

  A block of mass M slides down a frictionless planwly lkph; q-j wi6 13cvht-*w*e inclined at an angle q with the horizontal. The normal reaction force exerted by the pla;hkpw yqct lw--3v *jilhw6*1ne on the block is directed

  A block of mass M slides down a frictionless plane5n4lpk *ii)un +m.b8z x8sbs h inclined at an angle q with the horizontal. The gravipl5bb hn.mi8) sz+u 4si *8nkxtational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined w ;(gqfx:mc0s 8ve br.plane that makes an angle of 30e with the horizontal. Make a statement which best describes their accel;:m vc8brgfq we(s0.xeration after being released.

  An object sits on a frictionless surfacq hw-yl kb4v 66ympc54u5 e+gtk*(ekee. A 16-N force is applied to the object, a5+*hem( y6lpqw4t gk6ye cu 5kkb -v4end it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in 7.0 s. (,rtm3 o g:duw What is the average forward force om, 3g( duwt:orn the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 svxj7tu:p3) m l. What is the 3pm)jl v:7 xtunet force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which a;e ri , 5latt7nns;:udcquires a speed of 50.0 m/s aftert :udtnn;si7a ;5ler , 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 fod18n3 y6j1 /,co nrqwwj wa3t3y5 zcllrce that you push a 10-kg mass from rest,c1oz33r cw qn, t jd86la/wyy l1wjn53

  What is the mass of a pejbl27j q9g88fx 0ad rj,b pg0nrson who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface o) ni k:bjb9,zq0itu c3f the Earth whertzq nb:kibu,) i9cj03e the acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. Wha8t hfyzi7fs1 2kkw;*mt is the mass of the object on the surface of the Moon where the skh7f8kzi2 *1t;mf yw 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. 7f eln qvq3dk2emk*s0s7 -x2l The Moon's gravity is one sillds*2me 2 sn3-fexq kvkq077xth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-wab2fnmr1a;lq0 r by pulling on opposite ends of a 5.0-kg rope. Sue pulls witfq nral;m21b0h 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 atr8.f-m gpw(a+mh4, cijb/y F acts on the stack, and it accelerates a4+ y,img. ac j8h t/pb(a-rfmwt $3.0 \; m/s^2$. 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 48zc eu3 b4-6s8:i penwa0 N stands on a scale in an elevator. What will the scale be reading when thew 4c n3 esieu-:ba6zp8 elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in-u(a02c m 79 rhrcfmb-hvp2 wg12jrfj an elevator. If the mass of the person is 60.0 kg and the elevator acceler mg7j 1hm jr-02(wr2ufcc bapfh -92vrates 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 eb744x; rt.sln7lo 6qcmuvsq 8 levator. If the mass of the person is 60.0 kg and the elevator accelerates upward with an 6;8 lo7. bqs 4vus7ntlqmxc4r acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5,f8;akeg;y og+z sop ,.0-kg mass. One force has a magnitude of 8.0 N and is directed 8e+p g oygf a,;,os;zkdue north. The second force toward 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 a truck. It iezam: b8bbt:3 0,igm 6:u .vlha9ocris held in place by memmh bgie6oir:ab3v ba. :,89uz tl0c:tal 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 the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held itnt8mr4b q 5j-n 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 istj5 q8 t-b4mnr not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0zpbq*652*8 r e iungib.60 kg and m = 0.40 kg, what is the magnitude orbuie qzn bi82*p6 5*gf the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg h lju+ .eq1a jd8w6nas ,q+k2 :b3qntrand m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pul1: aheqku2dq6+t3+sqj.j8b,na rnl wley.)

  A student pulls a box of books on a smooth horizontal floor with a force o h(yx -vun*rzfe e9sr.8i-,e zf 100 N in a ,es -zzv9ufxyi-8rr.e hne* ( 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 smootx1v8e75 vcx wdh horizontal floor with a force of 100 N in a direction of 37.0e above the horic v1dxx w85ev7zontal. 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 shown8z els,5ke 6bj in Fig. 4-2. What are the tensions in thelj,ee8 6z5sk b ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mask3l-9(cexm) szy rau)s of the trafux(m)zy9ek 3) -rl acsfic light?

  Two boxes of masses m and 2m are in contact with each other on a frictionz5h vabedts p6m24+8 twq:h0s6-afom less surface. (See Fig. 4-3.) What do m4a pewtsh 0qh2v 8m:b+6f6s- a5tzis the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionless skhiv3( h* +uknwmb c//urface. /cm+n(k*h3b v/i kwhu (See Fig. 4-3.) 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.) If the -fksz 5r)oun4 forward force on the mouk5s f- 4nrzo)re massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a r w : ulm mgq;fdg,+uy6vu+8)waope. (See Fig. 4-4.) If the forward g+;d)+lv8f:gw wm u6umua,y q force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running ovtlh8od2+-nag cbu) c)er a pulley as shown in Fig. 4-5. Box2a)-got ud8 hn)b+lcc 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 static and kinetic frictions be;ck+9td q ka 0+h ow;i( lvpe)nvnc2o*tween a 3.0-kg box and a desk are 0.k;;o n( v 9+phcloiedw+)k c2*at0qvn40 and 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 for plastic on wood are 0.5ip; m sx1 c.ol4kv1vr7evz7x7 0 and 0.41 vkvz.v1p7irscl7m o;ex x 740,
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 slows and n0f.lco. mb e+b97 eolcomes to a slfe.0n7om9b ob. l+cetop with 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 horze/n1ge (tgt;c z h19enkfj7 /izontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the mot;/(gnzte gch11knze7/9 ft jeion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, yuolo1+ +q8i/r+,vy* jqaqo e 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 pwmiqx g*i84:a4ww i/w uck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the w/*i wi w8a:xmq44ig wcoefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic c+yjc,0u6e vknibnv q68r 6(daccident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and the roadway yuje(i66d qc,86c n r+0 kvbvnto 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 staaowf5e n-l uzo;3,+s mcked. (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 massios5m+z wu-f; a l3,neove box, what is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig.,nvzsl ;n4 n:o 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 lo; n nz,nsv:4box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless i1 -7szlncv mvh:wk.twvm(3 i5nclined plane. The plane is inclined at an angle of.wih3:zmnclvkw 1s5vm -v(7t $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that ma 3k h.bds+qg :*iw4kjcts o6-nkes 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 i/st4a t s3oy)r. :r0i/jvtotgnclined 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 sy 515oifi n.gplane 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 inc132 eo kzokul1lined plane, at a constant velocity of 6.0u1k 1kel oz2o3 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 down a ro o,ttwx zf4gcne-2,9w7f4 r uzugh $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass m slik5z(wk -aad2gq1 6zp ydes 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. The cable at6ovl0d,/xeigi6 m; lhe .h1 letached to the log iv1 g,lo. /i66;0e mex lehldhmakes 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 on a roughx-+e j;.pbtss inclined plane tilted at an angle +.tsxjbe; ps- 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 pxh(.)i6ktxx rj8e nb3lane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is (tke8xxj6 xb rn)hi.3the coefficient of static friction between the object and the plane?