Which of Newton's laws best explains why motorists sho9p1qfm 2whyk ck; mo15mpl2 6guld buckle-up?

  When you sit on a chair, the resultant for se axi(xerj :95jxyd :(i2dw7ce on you is

  In the absence of an extdh mm+ ulhw4 p4kcv5cj9qd, /1ernal force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are sudr+p/r ,i6fml idenly turned off, while traveling in empty space, trr p+6f/i,i lmhe starship will

  A rocket moves through empty space in a straight line with colu*cj d7h- s+;zk-clxnstant 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 motion ilxlzc -jh-c 7uk*+ sd;s

  You are standing in a moving bus, facing fo4a tekfs zmc2l wzhw598vx,3- rward, and you suddenly fall forward. 2,8la fv shtz 4w 3-wx59ckzem You can imply from this that the bus's

  You are standing in a movin1hdx3c*8 kx kck*gak2g bus, facing forward, and you suddenly fall forward as the bus comh 3xxd g kk*82kk*cac1es to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Desvoj3 +7v-ojzk/sm k v+cribe the motion of the object.

  The acceleration of an object is inversely proporth ydd+)7 ry2jsv3io,yional to

  A net force F accelerates a mass m with an acceleri fnzs t :6,zl9upq:l.ation a. If the same net force is applied to mass 2m, then the accelezzsl :ql. n96f:ptiu,ration will be

  A net force F acts on a mass m and produces an accelerationzu - f(5wm2ocg a. What acceleration results if a net force 2F ac(5-zcogu fwm 2ts on mass 4m?

  If you blow up a balloon, and then release it, the balloon :pw 8md6vj ak8jf.nd,will fly away. This is an illustration j,a kw86p8df:mvj nd. of

  Two cars collide head-on. At every m;d(cda 82b2dp:;t mal1 yv vzioment during the collision, the magnitude of the force the fii;1v ;m8y(tla: bdac z2 2ddvprst 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 1q.op a3-e l jhieg+,kwhich the object exerts on you will jh -1ila,eg3op.e +kq

  Action-reaction forcex ;yfn5waf 9 /90ppxypf7kd0w s

  Action-reaction forces are8*mz-vzs95zu xn0 (foea r*cm

  A 20-ton truck collides with a 1500-lb car and caus .i+ bdblzuap0k+ gut+fe;(v ;es a lot of damage to the car. Since a lot of damage is done on the ca;f e bap0zt.;v b(++kuiul+dgr

  An object of mass m sits on a flat table. The Earth -52pw kspjt r/grxt00pulls on this object with force mg, which we will call the action fpskgp0-tt rx 05/ 2rjworce. What is the reaction force?

  A child's toy is suspended from the ceiling by meanxz(f4l /kc j.is of a string. The Earth pulls downward on the toy with its weigjl/4c( .zfk ixht force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you wit9p*+*pnup uq fh a 1500-N instantaneous force. The ball hits the bat with an instantaneou*pu q u*p+fpn9s force, whose magnitude is

State Newton's three laj u1y: m*dqm,dqt(h 0uws.

  Mass and weight

  The acceleration due m8pcakfc73 1xi*w h +ito gravity is lower on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, cox+ikmc8 w f73p ai1*hcmpared to Earth?

  An example of a force which acts at a distanceuk s5fjl 3:rw* is

  Who has a greater weight to mass ratio, a person weighin1.tfot9utzb/4 ;j 9sbem p9ljx8 psx*c;c 9atg 400 N or a person weighib9 tejxss tto ;9cf481bt/mc jl* p;u9a.9 pxzng 600 N?

  A stone is thrown straight up. An(j5.3 kp7iz luyx qn)t the top of its path, the net force acting on iqj )i3.ky znp( nl5x7ut is

  A 20-N weight and a 5.0-N weight o 3ka4fgiz-5glhc * b -rv0cu-are dropped simultaneously from the same height. Ignore air resistance. Compare their accele3--*fbzko 5cgv0carhigul 4 -rations.

  A brick and a feather fall tvzq;k0f) paq1o the earth at their respective terminal velocities. Which object experiences the great1f p) q0;qzvaker force of air friction?

  An object of mass m is hanging by a string from the ceiling o- 0gf :x-v 6llyor/zul nw3qxu f8.dj9f an elevator. The elevator is moving up at constant speed. What is the tfu0 :l9yglx r 8vn-q3w6zdl.-xfouj/ ension in the string?

  An object of mass m is(x wam 9+1b.knpasw f2 hanging by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What pa 2nfsxmkw+.b9w1 a(is the tension in the string?

  The force that keeps you from sliding on an icy sidewalk isv+:,xub )j3:yjlf s6sf- nej o

  It's more difficult to start x.*xn1t pub9j0xc fu x5: zs9tmoving a heavy carton from rest than it is to keep pushing it with contz b *cx:xntf9.jux 1u x95s0pstant velocity, because

  A horizontal force accelerates a boxo+*;pdej0 z67piy jfm0vok u7 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 horizontal force is doubled. What07zk7yieoof6 0muvd p *;jp+j happens to the box's acceleration?

  A packing crate slides down an incliu.2q obe f7o.jned ramp at constant velocity. Thus we can de.7ojuq b2e.fo duce that

  A block of mass M slidesk*es/j; z w1pn /oin8c down a frictionless plane inclined at an angle q with the horizontal. The normale 1/c os8zjnp *kn/w;i reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q withx x)e1o 1)9cybh2u xora,w8m j the horizontal. The normal reaction force exerted by the plane on the block is directrjycm 1o))ox8ewaxh1,x9u2b ed

  A block of mass M slides down a frictionless plane inclined at an angle q(:;/qf dxm3r hw ub typoaof8d *w/,x8 with the 3y8fuh /wd, darmx (opq t /x*o;w:8bfhorizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are relea9p h rs;5nk1ltsed simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make sk1 ;lhtr p59na statement which best describes their acceleration after being released.

  An object sits on a frictionless surfayu6mkqm u23 j:ndo/sai766w u ce. A 16-N force is applied to the object, and it acmoyw 6nj66d7s:uuk /aq2i3um celerates 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 frb2e 6hxxou+t.(( es jxsq6ow 4*5m bm/s in 7.0 s. What is the averu4r*foe + hmxtjo62(sebq. 5xwb(x6sage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s/d vks7ghjac ;q-s fjl:du1.0. What is the nesh1l7uj:j; g.dv -fc/d qsk 0at force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acqus/7.+wsh ga hjires a speed of 50.0 m/s aftesh+ /7wsh .gjar 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 force that you push a 10-kg mass fromao8fsqv . ffv(1 *mrh+ rest,* fqvh .r(1fm f+ovas8

  What is the mass of a person who weighs 110 di7ao72slfoj*8 e9 y qlb?

  What is the mass of an object that weighs 250 N on the 6k0xml8w07jr h idhy4surface of the Earth where the acceleralm iyw040dkh87 h r6jxtion 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 objzi1d0z,fo) vc)srh *t1)lslaect on the surface of the Moon where the acceleration due to gravity is only 1/6 of that on tsrvil 0s,*1alhct z)fzd1o )) he Earth?

  Object A weighs 40 N on Earth, and objec tnb0*+0eurftw ;z: ibt B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of the obje;b f:uwe +*br n0tti0zcts.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5.0-kgrmikv voz/ l;n8v./o 9 rope. Sue pulls with a 15-N force. What is Sean's force if vv9 v;/ /o. im8knlozrthe rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books restsrm a0bl41-mdo on a level frictionless surface. A force F acts on the stack, and it accelerates a m0b-l41o rdmat $3.0 \; m/s^2$. 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 ;v mn .(nva6pton a scale in an elevator. What will the scale be reading when the elevator is accelerating downward atntn ap6;( .vmv $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass*qdi5/ cu.zj rlxqo9yx/.x *h,a)rxn of the person is 60.0 kg and the elevator acce* ./h d.irnxu9laz/5jx ox *c),y rqxqlerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in az). enag:,uvepq7k 4.jz2gz jn elevator. If the mass of the person is 60.0 kg and the elevator accnpj)72e.je, 4gqu.a: z zzvkg elerates 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:;bhjar, k5bb sbw, 0c-kg mass. 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 mass?r ,c:0b;jkha,bb 5wsb

  An object of mass 6000(*mh.7 n-fges.: i tzy cs;esm kg rests on the flatbed of 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 distance;yeti*hm7n m:(esgs f.scz. - 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 wjt7 3jgbi ;z-w(yq9sin place by metal brackets g9-7;yj w3( iqtsw zbjthat 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 forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg andlu5yx 8d qs4 l7hqh+8f m = 0.40 kg, what is th58qslxu qfh+d8y4 7lhe magnitude of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-fj7a ;laj,,r ycws.1g1, if M = 0.60 kg and m = 0.40 kg, what is the tensioja 1,l,aw j7yf;grsc.n in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of booksax1x8sdhtbw 66ua u63 on a smooth horizontal floor with a force of 100 N 68hxuau1w b6 xsda3t6 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 floor with a forr mmmmq f2,,07ila3uc ce of 100 N in a di,au,mrlm32c 7q mmif0rection 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 r8d btc* ht(+xne9m( ouv:za1popes as shown in Fig. 4-2. What are the ten8(1zdu:+th(m p eovcb 9 n*axtsions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50d unth-bvol)jr(1-u4, pugw) N, what is the mass of the traffic lighung (p hbulo 4)wv-t,d ur)j1-t?

  Two boxes of masses m and 2m are in contact with each other on a frictioh3)5mwr sq0qsmk 7a7qnless surface. (See Fig. 4-3.) What 7a07wh sqksm3r)5qmq is the acceleration of the more massive box?

  Two boxes of masses m and 2m are;9 *hzs:ruf :x9v9ymei , d gs7r(sckv in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on thezv9 y,fheugd ;:sv r m:9cs7xs*r (9ki more massive box?

  Two boxes of masses m and 2m are connected by a rope. (Seeyg)mgj hh0us fk j5.jmb-7 ,sbq3r o3z xxg32* Fig. 4-4.) If the forward force on the more massive box i7j *m5kxbjs g qx3f3j3uh)mh, or-z2g0s.ybgs F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.pl/fcqyb2os :/c8u:m: a k;m v) If the forward force on the more massive box is F, what is the acceleration of the less massi/qcub/vmly pofsm82 ::ac ;k: ve box?

Two boxes are connected by a cord runnin ftvxj0rwml: 2 x th*a**2ru6lg over a pulley as shown in Fig. 4-5. Box uwthf: axvr0rxj m lt6*2*l*2I 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 between a 3.0-kg box and a desk y emcqh30t/8u are 0.40 and 0.30, respectively. What is the net formet8 q 3ch0uy/ce 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.e8 tqc 9,x po**fe9r7yqis7dq 50 and t 8*e*97iperqcx 7q9qfydo, s 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 +x direction. It slomt (c ,wn,j5wpws and comes to a stop with a constant acceleratiow,(np5jw ,mc tn 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 f+ r g5bcl,2ceworce. A 3.0-N friction forcwlrec 25bg+,ce retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mas3iej li eu:ju.++ 3evus, 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 anpab v v-:b89ajf,+rlx yx :ia j oq2/3bge9rp. initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient ovvp x2-b x9.ya+b f:p 9:a,ogl/rj8 ab3 irjqef kinetic friction between the puck and the ice?

  During the investigation of aux pgb n6jw)3nat 4d:9 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 thendabwx: jg)nt94p6u 3 speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See -a-u.f0cea3 nio- mt oFig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between the boxes iom.ae io 3-0ft-u- ancs 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. 8d9o6 p o*sgkd4-6.) The surface between the more massive box and the horizontal surface is smosd96o*g o8kpd oth 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 boxes?

  An object is on a frictioroq.r:dn y1.a1fof0onless inclined plane. The plane is inclined at an anglrfr yfoon:1da o1..0qe of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hil.yit/,w6yw o5 blnfe;l 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 riq7mq wd+ 6 tq4; zk;mypq .+hw(ud)oplane 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 inc2f20j pahoaoqd5j8 fh1brv v/v *7 -jzlined 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 plane, at a constant velocdi ,k4/.x 4f jvik(kk*pt(yjhity of jkjkkiy*.,xvkfh/ ((4 idp4t 6.0 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 dowm) .;c+y9mwe *zioxi un 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.xwfo88b (mvfgss89)siwz v (p )0vbl 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 weighin0y. reom 227h7ixl; mcamg 4jsg 500 N along a rough surface. The cable attached to ths.m7jo0cae2 7l;yx hm4gimr 2e 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 on a rough inclined plane tilted at an an9gi-3m;nw,1d7q w pxlu,o hws gle o;dgql- 7ni hw,wpo13u w9s,x mf $33.5^{\circ}$ 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 inclwsdlz: ig(+/qined 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 stat/z:sw(iq+ l dgic friction between the object and the plane?