Which of Newton's laws best explains w97yi ,g5yjsf fff8x:qhy motorists should buckle-up?

  When you sit on a chair, the resultant force on you c s65ycr- wi 5ogk-0hg:we)r ais

  In the absence of an external force, a mo om+fp56dhi3 n(b;pwfving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned ox1x.s.+-nu nn5jy8jb8f.wwg oi3 zzkff, while traveling in empty space, the starship w.-jbs8f.w nznn8ywk+ 3 5ogijx1 xzu.ill

  A rocket moves through empty space in a straight line with cono45s5jyzr7nw +gwe rk8fq g3:stant speed. It is far 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 motioo z3wj5+ gy4fsnew7k: q rgr85n is

  You are standing in a moving bus, facing forward, and you suddenly fall fj02hq,pq. k paorward. You c k,pa.qqp20jh an imply from this that the bus's

  You are standing in a moving bus, facing forward, and you ,r .v4jenq ymugvw0b:h+7cr 4 suddenly fall forward as the bus comes twj 4 .bg ychq,u:vre7m +40nrvo an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motio nmy+:7wx*q3z qr 4dmzn of the object.

  The acceleration of an object is inverslig- 6 (g0hup8j wgw8dely proportional to

  A net force F accelerates a mass m with an acceleration9sjuxv- 5;otgzt* + py a. If the same net force is applied to mass 2m, then thj5t-9 s; tuypgzx*vo +e acceleration will be

  A net force F acts on a mass m and produces an accelxg+9ny/3mlmw eration a. What acceleration results if a nxw3lmg9/m+ yn et force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon willlx4xf;u2x f-t fly away. This is an;xux-4ft f2lx illustration of

  Two cars collide head-on. At every mom :vt*4wlbja,f r 5gwt0wl(/ukent during the collision, the magnitude of the force the first car exerts on the swl*fgrlw ,t54:kw ja v/tb(u0econd 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 fofjip 5fkz 3ra+vcmvjq9t8 r3l ,in*6*rce which the object exerts on you will,+rv 6 v f*i5n jjmf3 qia8k*zrtcl3p9

  Action-reaction forcegw3m1 5joma2tz0,adu-2 b cd ./6ucw8ngauojs

  Action-reaction forces ar) 3tb 5sk8b jowu0/bmhe

  A 20-ton truck collides with a 1500-lb 5k +3n9jljj4fjq v.jta yu)o)car and causes a lot of damage to the car. Since a lot oflot j j5.9)n4jv aj+u)qkjf y3 damage is done on the car

  An object of mass m sits on a flat table w8+5n)mgh,w/zx r xkkm4 8izj. The Earth pulls on this object with force mh +m8zgj)k5zwxri w nm4x8k,/g, which we will call the action force. What is the reaction force?

  A child's toy is sus * azu:;fou xn6/oty.bpended from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. Ix ozutu:y6;*ofa. /bnf this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. Thee4*ve, opmyaj: 3j 4lw baa44 jow,*vle3 p:e mjyll hits the bat with an instantaneous force, whose magnitude is

State Newton's three lawshy-4i3 as vr;n3e2xx go6;uu6 ts0nvd.

  Mass and weight

  The acceleration due to gravity is lower onbbfp/ 7b kfh,91wuo4n the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's sur7wbup/ffbbok,n 4 9h1face, compared to Earth?

  An example of a force which acts at a dis3:wa 7a 1eflyrtance is

  Who has a greater wed gs,uq :-hk+fight to mass ratio, a person weighing 400 N or a person weighing 600 +gk dshf,q-u:N?

  A stone is thrown straigh5dedh/mn5 w fin,4n/kdn)h+6 0ghpu wt up. At the top of its path, the net force acting on it id wwhnf) h/deh,kgp/i 4mn556+0d nn us

  A 20-N weight and a 5.0-N weight are 2m z-qfjbrai( v63x xd)nzs,5 dropped simultaneously from the same height. Ignore air resistanca2 vbz j6dfnxm(qx -i 35zsr,)e. Compare their accelerations.

  A brick and a feather fall to the earth at their restj.jqh q ou06k/*r7m0am/wq 9ckevz;pective terminal velocities. Which object experiences the greater force of air friw; m*r7 o0.qqq6/km av/kjthj 9uce 0zction?

  An object of mass m is hanging by a string from the ceiling of an elevator. The*g+t)msk vs0o1 b*feu elevator is moving up at constant speed. What is the tefk1tvge0s+ bus**) monsion in the string?

  An object of mass m d) ,xgptn:ts3is hanging by a string from the ceiling of an elevator. The elevator is moving upward, but slowd gt3s)p,x:nting down. What is the tension in the string?

  The force that keeps you from slido31g.lfmj hmhzck( :4 so7h2w ing on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it iunyu am8o-o7,4ate)m s to keep pushing it with constant velocity, becaus omunam,ou-e)a 74yt8 e

  A horizontal force accelerates a boxhdyh. c4 ( r bxophn3+b+l)e7b from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the hor+nb( op. 3hcb4 e)dh hxly+7brizontal force is doubled. What happens to the box's acceleration?

  A packing crate slidezxw(4j2w a)*a g-f efb8qzf)vs down an inclined ramp at constant velocity. Thus we can dez4v8aefaqf *)xz(gwjf bw2- )duce that

  A block of mass M slides down a *7zdx15p,eu 3msoo khfrictionless plane inclined at an angle q with the horizontal. The normal reaction force es75ho*md, xkz3e 1upoxerted by the plane on the block is

  A block of mass M slides down a frict(4xxw)pudxme m 2 0a9jionless plane inclined at an angle q with the horizontal. The normal reaction force exerted xa(4ewumm90 px 2xjd)by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an 1ixrje/dlro-i8s 89 sangle q with the hox8/i8jios- 9 rerls1d rizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) ar n6blxv9zf3- pij. u3/lgu p5te released simultaneously on an inclined plane that makes an angle of 30e with the horizonta9pv3 xuzn.-tjig 5u6pbl /lf 3l. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to th n tva8cjcmjyw(;au/ a j:.()pe object,jjtuy( caa mc ./)nw(p;vja 8: and 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/s6c f aoews4j5crm z30, in 7.0 s. What is the average forc6zwer5f04a m c ,jos3ward force on the car?

  Starting from rest, a 4.0-kjn0bmamwy3( ) g body reaches a speed of 8.0 m/s in 2.0 s. What is the net force actm(b an0j) my3wing on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed 0+tm4jg1m )bv;7nur zcw3 a ijof 50.0 m/s after travelic7g4z ajm t)10ivbj; mu+w rn3ng
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-kg2j 2nvup ,0pqg mass from rest,0u2 nq ,vpgj2p

  What is the mass of a person who weighs 110 lbju a.0a7xtsjis . g-f;?

  What is the mass of an object that weighs 250 N on the surface of the Earre2u)lw( *xg oeg.wx7th where the acceleration due to 7l rwwx *e2xgoe.gu( )gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the objecs8wt5t3gid e xt mw,h+qu)d+ ;t on the sues8m+t,dw5 3wu;t tigxqh)d +rface of the Moon where the 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. T:tq9 22 f5f(h flstamlhe Moon's gravity is one sixth of Earth's. Compare tmt2ll9ats5( f2qhf f: he masses of the objects.

  Sue and Sean are having a tu+/ii zu5qu 8vp6uomc0un * f+w-elm)bg-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 rope5/p-io *bz)unil 0uumfcwmu+e q8+v6 accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a leves8 c:0x2eb*acxwhf m(l frictionless surface. A force F acts on the ss(cmx e:8c*fabx2 w0h tack, 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 y tn5f:, z,,.b+cnhmyuff 0y4kwv(zmN stands on a scale in an elevator. What will the scale be reading when the elevator is a (4, hnyczyvkff+ 0fm.,w :5yt,bumznccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevatorgq7gay-mvin 6e+5u6g1 b(dff . If the mass of the person is 60.0 kg and the elevator accelerates downward with an a (ngqi+-g 1m5ydvg6efbuf 6a7cceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator.clf 97. uggb eb*ntq01teqbm(6lj:r9 If the mass of the person is 60.0 kg an6:fbgcge t l1.7lqr9 9b teqj(m*0bnu d the elevator accelerates 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 mu*r8k: . sxmoxm vq2 39b9cwimass. 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 masswso8c.*b9mv92 3kiu: xmr m xq?

  An object of mass 6000 kg rests on the flatbed of a truck.pgwkq td j;zu+ +8)ecz16 geg7 It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck i;eugkq+6+epjdcg t1g z 7w)z8s 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 oyl9ub(8yqp4bdj 61flf 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 timeyl46qu j18ybf 9pb( ld if the load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg anet-r,.quhz-f0 iugvj.m 3u 0vd m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore frictionjz 3.vih0gr,qtm .- feuvu u-0 and the mass of the pulley.)

  In the Atwood machin/imxxu w j.bi 9 zz*a923vah)ye shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction az awy*9m9) x3.ixbzj/2aui hvnd the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of 10m z tkjt*uq 1aqc30jqod;653h0 N1ouq6t3cmhq * jda5q0; zkj 3t 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 b) 37a1t fyismlooks on a smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of thy 71)it al3mfse 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 shown in Fig e ocgy01nk :cckvzya,(x c6fa-260or. 4-2. What aacvyfo-n c 01xzoyg(0kccr ke626,: are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, wof0 :kpo +yi+phat is the mass of the traff+0k:py+f pio oic light?

  Two boxes of masses m ro(l: * xzrv,kb0ons ep/* gq7and 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more/ zngx: *7,kb*lrs0rqp(eoo v massive box?

  Two boxes of masses m and 2m are in contact with each other onzo8lwn* v:j u9 a frictionless surface. (See Fig. 4-3.) What is the netu 8zon:lv*9jw force on the more massive box?

  Two boxes of masses m and 2m a r5g8 8+xsh 8gvtioe5 jx44k(ii yyol:re connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, 8:sle+4gox4kiyy 8t5ii8 j5(vhr x ogwhat is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a +be 4(arfv1f.qj obl0wh7p;p rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less je 4q v;h+b.1fr7op0ab(lf wpmassive box?

Two boxes are connected by a cord running over a pulley as shown in i2 ,nwq,mmdcfs4u c/s4c02uyFig. 4-5. Bni/2y 4fcdw04 smq2 cuu,,mc sox 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 an e/v5*tde hil.d kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force isi. l/h5t evd*e applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are fxdcc-oaf 1b.u5 v /3 *ru2 .mi;huhgc0.50 an3huc-x obuc .v * gr1/imhfc2 ;ufa.5dd 0.40,
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 s* g 4roj;eqvr v+ xdrp6r:k.1+x direction. It slows and comes to a stop with a constant arpgk;46:exv1rv*o dj r.q +srcceleration 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 qoi m 3h)/px*tkv+*et g+jk (ohorizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retav / go *iqmxk(th )ot+ejk3+p*rds the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelera.c/,eh.eb2 wgwsb4 s ftes 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 givencpvaj u39b 2z+ an initial speed of 10 m/s. It slides 50 m on the ice before it sv9jp +32czabu tops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigati5yy(v;g a-;ecpiu8w h/1jfq mmd (7qv on of a traffic accident, police find 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 th(v pc evmfm1;7y( 8dijq5;ygqwau/ -he 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 obq tbhqun0zs( 7 ( l*gmdl*/-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 isqb */zg*ulqn7( - otd0 bm(lhs the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface ;pd;seot lt0uog 43wcz:)0w q 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 coeffptc;wdze3lo ;t4gs 0o: )qu w0icient of static friction between the boxes?

  An object is on a frictionless inclined prsjz mfms +r r77mrfh,1.9wz4lane. The plane is inclined at an angle mr rm j1+wrfzss74rz,h97.m fof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angleo*qv kn4i*m+o 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 an angle of +x7,4kcnt9-1wu /*r cugk;z gs u omuz$37^{\circ}$ 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 inclinedxnh 2ou+f 661t hn3rey 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 direct(4o-zj :yl r 2gr5ckfq z.mc8xly down an inclined plane, at a constant velocity of 6.0 mrlq4xc- yj5zrgzk c(o:f 82.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 dows, -d5wz zej s;a;oracl:j;j5+9pyjon 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 rour1j+ q7 hfdd6ugh $37^{\circ}$ 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 attache(n:vw+0e vtf 46 wb s39zixmkcd to the log v4w (c0 bf 6zwivmsnx39et:k+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 c/msei,4rv d 4from rest on a rough inclined plane tilted at an angle of,ed/44 is cvrm $33.5^{\circ}$ 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 incl hoz5i,jdili 9:o 81peined plane. The angle of incline is gradually increased until the object begins to slide. izoj ih9:p l5,1 8eiod The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?