Which of Newton's laws best explains why motorists shdad t6x4h*(mv ould buckle-up?

  When you sit on a chair, the resultant fo.+:n*f1l h zqmhepc;l timi8 u u46tb.rce on you is

  In the absence of an em ugrix9 eq944 +dev.bxternal force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are sz,.tsu 6)s:jqe)lag xuddenly turned off, while traveling ius)szj6 )gel,q a.x t:n empty space, the starship will

  A rocket moves through empty space in a straight line with constant syz :ay5duf:) *k/ a+k*ty)ccy9p ete wnem*z7peed. It is far from the gravitational effect of any star or planet. Under these conditinypft* w mzk):)c5 t/9*d yuaay* :eecyezk+7ons, the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forwardda/ wg f0:2fuh, and you suddenly fall forward. You can imply from this that th ufa 0gwd2h/:fe bus's

  You are standing in a moving bus, facing forward, and you sud+acexwt )gaefgzsy5 /,o +,p)denly fall forward as the bus comes to an immediate stop. What force caused you to fall s/ 5paweea ,)tfg+zg cox+)y,forward?

  A constant net force acts on an object. Dez,a.p1 osew f)scribe the motion of the object.

  The acceleration of an object is inversely proportionaszx n* f3p b5j)vv 9ah*+z,cbbl to

  A net force F accelerates .hw3ca fx7h17k xhu q3a mass m with an acceleration a. If the same net force is applied to m3a7 hxhf.w xqc73kh1uass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an accelerationod.v ) x n9x (,vnmlxey*x-4dw a. What acceleration results if a net force nv xymde(*x9x-vn) o l .,4dxw2F acts on mass 4m?

  If you blow up a balloon, and then release i5gmw z hk:u;c359ot96ji lpi ut, the balloon will fly away. This is an illlzikj:653 9upih5;tg u 9owmcustration of

  Two cars collide head-on. At every moment during the collisd4( m;yk8k3jp0rlx.m1c4ohou w+ hcjion, the magnitude of the force the first car exerts on the second ym4l k(.c4mcor3w hujd80+xho1k;pj 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 exerts on youc:j,*xtqy n2v wic ,x j*vt2y:qnll

  Action-reaction force 0vyfe5h;i+ / gwek:gos

  Action-reaction forcesu6gq3bqq-bqgfu d(3 *cgm3h7 are

  A 20-ton truck collides with a 1500-lb car p/ (11xyo6by0g/)kvyt zp ukeand causes a lot of damage to the car. Since a lot of damage is done on the yu0ep/(g6y1pvx zbk / oty)k1car

  An object of mass m sits on a flat table. The Earth h+o s 4)sc+jkqpulls on this object with force mg, which we willc s+s4k)+o hqj call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of,.4hrh.na vh m a string. The Earth pulls downward on the toy with..,h vanmh4h r 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 instantaneous for )plfv*x0ranzje() 4xce. The ball hits the bat wit f*a) j0vzxrl(ex)4 pnh an instantaneous force, whose magnitude is

State Newton's three ija9b1cbn() elaws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Eartp-o-pkf9tl w 3h. Which of the following is true about the mass t-pwf9 -ko3l pand weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a forcel7mr;3vm7t u+ .suirtk vz ,j2 which acts at a distance is

  Who has a greater weighthk/g9 wc*oh.p to mass ratio, a person weighing 400 N or a person weighing 600oh kcp*/h9 gw. N?

  A stone is thrown stra -x ktsgfk424h(or(jn(kh(vduc. 9b fight up. At the top of its path, the net force acting on it hbkfk 4x (4sncf.2dur(jhgvo((9- ktis

  A 20-N weight and a 5.0-N weight are dropped simultaneously from thdlk/z 244cvo o0vfrw7j, n;qh e same height. Ignore air resistance. v;wdhklf7 no4c 4z,v0o/2rj q Compare their accelerations.

  A brick and a feather fall to the earth at their respegd/xhe(w)buop: l7-s ctive terminal velocities. Which object exper7 ow /xbe p)lsdu-:(ghiences the greater force of air friction?

  An object of mass m is hanging *pt *dkikslzk sq7nt, /f)*e.by a string from the ceiling of an elevator. The elevator is moving up at constant s*7) e*./tlk qs,pz nsk*kdiftpeed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of gqx : nfx sg:1:v(obm+an elevator. The elevator is moving upward, but slowing do gmoxf g+: 1(qsvbxn::wn. What is the tension in the string?

  The force that keeps you fr 4klf lw7nyh:.om sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to 1ty/ tjl: 5n-sjc/xuykdjhu+)vb - :dkeep pushing it with consta/k- t1yj -l j+j: uu:5ns/cd y)tvhbdxnt velocity, because

  A horizontal force accelerates a box from restodces aqf: w+:(:t,th across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain thew ::qce a :+ts,(fhtod 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 constant ow4 kw/e,5i q6fboi 46q* hnulvelocity. Thus we can deduce t n,wui e 6q4k5*qolhb/fo6wi4hat

  A block of mass M slides down a friction uzr4 +btp;f*xless plane inclined at an angle q with the horizontal. The normar;p t *u4+bzxfl reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane )im)u ks7g m d5poqecf5ur7*9 inclined at an angle q with the horizontal. The normal reaction for p ur7)gdo)i 5*5f9q7kms uecmce exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q witk;l d)p,ta2jk4 vf9+ucaxvc. 1zkk (r6 p1jr nh the horizontal. Tz4 9uk2kl j ;r)afa jr cp,1+k(6kc.vnvpt x1dhe gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are 97rvx .hib+ p1pwvc7ow5zik1 released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement whvhwip riv5wo1zk+cb9x. p77 1ich best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to the objec 9a;a(w8 u2r jh2zs02qlmvzavt, auq282( r w0 2 lzjamva9szvh;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/s in 7.0 s. What -h7 gcdg02pbdz 9/ezf zmo-(ris the average forward b h 0z g pf2d-9(-odczmzg7e/rforce on the car?

  Starting from rest, a 4.0-kg body rtunfu)ye5.lsm - t-b3 eaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on theu-l)ftn3yus5 .mb t -e body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed es;: zmkks,zk; sam/p:+ 9f dgof 50.0 m/s after travelinkazgzes/ fmk9::;;p,s +k sd mg
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 from my0) w8ruey(bb:xaz- w, -zsh restz:r(-my08 s ) wuxewazbby-,h ,

  What is the mass of a person who we0umo8/ac8fip96f no9li3 eii ighs 110 lb?

  What is the mass of an object nuc 4kg u1oj d(m) vi72zp(b5ithat weighs 250 N on the surface of the Earth where the acceleratim niboc7 z41djgk( u2iu5pv)( on due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is kz 2sx9lv8a.fj wknt -dv8sw4 1p6 e5xthe mass of the object on the surface of the Moon5sjw2-f9 1.a tev6 w sxx8l8nvkd4kpz 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 p8ywj 9 mbjc/ja*l)/ oon the Moon. The Moon's gravity is one sixth of Eaby 9 )8cj/jwplao/mj*rth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5.0-kk;2j s qn0v4nbxq-) ipg rope. Sue pulls with a 15-N force. What is Sean's fo4 n0 skn-qqb)iv2p;jx rce if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a levxtxs+t4i y zn7+-2 n0r 2aafulel frictionless surface. A force F acts on the stack, and it acce 7n2na0 4+la2z+xiur-yttsxf lerates 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 elevat.yr3*ukxr czu2w(/m y or. What will the scale be reading when the elevator is acceleratingrwy3rm*u.c(k/u z 2yx downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator8sx 4 6gdb8 -metyh,nn. If the mass of the person is 60.0 kg and the elevator accelerates downward with b ,hs-68nmndyt8g4x ean acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale ride .ttadqaf,rab :6.nr f0h ;qv,s in an elevator. If the mass of the person is 60.0 kg and the elevator accelerates hqt..f;rafarn:d, 0avb,t6qupward 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 4keagsz .g*d *mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a m*eg.4z* gsadkagnitude 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 is my: zbpti:o1yy *j5*e2twa k8held in place by metal brackets that can exert a maximum hori*1e mtkzj:a y2 5bo:t wp8yiy*zontal 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 x5u h ;z9x;kjthw 3c1t:,eeec kg rests on the flatbed of a truck. It is held in place by metal brackets that can euc;t , x:ceke3 e1j9hz tx5w;hxert 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 and m = 0.40 kg, hs0 ,o , gaj mks(6:csz4dqg8wwhat is the magnitude of the acceleratwsg:sq a6s,jc,d8 4 go(0zhm kion of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0hr.e f:3z4tf2c tfo yr-r6 4fr.60 kg and m = 0.40 kg, what is the tension in the string?rrt 2feyfc4-of tf.r36r:4z h (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smoo oku cwc/bt sf2g vx;v7)88ki3th horizontal floor with a force of 100 Nt8k3o7 gwvc 2x s k/)vic8fu;b 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 adncc yj; af5 y03c5);-kwtveh5 n4getc8 wut5 smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass ock)5gwn3wccuec - h 555 ;jeyyadv0t tnt;f84f 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 su1f uatng:4os 4pported by two ropes as shown in Fig. 4-2. What are the tensio4f1ntgs : oua4ns in the ropes?

  In Fig. 4-2, if the tensionsl4/t f bkw6da5v e.d:b in the ropes are 50 N, what is the mass of the traffic li/t d b4e:da.vfl6bk w5ght?

  Two boxes of masses m and 2m are in contact with eacq whvs, 0n be5afxj9qdn:*3 b.+g 7pmqh other on a frictionless surface. 0+7bj3 5vshpq,9qmxae.q: nbgnd*w f(See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contacte5cb- mrph 26easq 2/p with each other on a frictionless surface. (See Fig. 4-3.) What is ta- e/h6c me rp2q2p5sbhe net force on the more massive box?

  Two boxes of masses m and 2m are connecteuj *f+o:.d)drl do do.d by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension i)ofd udo+ rl.oj d*d.:n the connecting rope?

  Two boxes of masses m and 2m ar x bs8,)w 7nbc+npsjv7e connected by a rope. (See Fig. 4-4.) If the forward force on tnnjs78b,w7c + xp)bvs he 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 as5c ulev1,vc. r8d- 7yeis xdlqx6h n*. shown in Fig. 4-5. Box I of masl nv.,xuh .l-vy8eiedcr s 75c*d 6q1xs
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 kineticifu)s,npub8 jp zb ip7*9u0 er9qnq+9 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 is appliezbqpfun 9bp0 u*9qs8p+nue7i9i r),j d to the box?

  The coefficients of static and kinetic frictions for plastic on woodmd2wz akz62x ; are 0.50 and 0.2k2 zzx m;wd6a40,
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 dip3v5 bm7: bnb cl)bxu-rection. It slows and comes to a stop with a constant accelepxmnc 3b b) -b:bu7vl5ration 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 pull1 u9kwzf yd+7p-q:9p3:4mvjc mbyhzced by a 5.0-N force. A 3.0-N friction force retards the motion. What is the ac4mzjv k:f1mcbd :p+uh 73yyp9-qcw9z celeration of the object?

  A horizontal force of 5.0 naosnsyhzk s+ aqn(/1 a/)0(:jus5qs N accelerates 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. Iqi 5a+ymaapr+upxaw p z-:o:px;; f/:t slides 50 m on the ice before it stops. What is thef: q/mup- pyr+px 5:+:wxa;aaozi p;a coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traff32ak h. /pfyqv2/(om cnh-fnwn7u1 u fic 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 prevaila kf7hwf-3uo22nf (/m hn c/nyq1.vpu ing conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. *:5sh yrzf *jw(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 s5*zjyf h: wr*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/y,kc4 ogp,bi -x d d8q0z-s8 qdp2vsv. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface between 2/z-8s8gcpvd kb,dd- s qix pq o4y,0vthe 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 frictionless inclined plane. T+ l0t8ml4gkjx he plane is inclined at an angl48gx 0t+ jllmke of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes b9t0sd8vvs ( /t-ohax 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 ywe*v 73 rxio2with 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 ix l-f:h,dq4 t9s3p rg8rosp5/j+tq c hnclined 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 downkw6a+r.-9oqojt -j 9dmv/gis an inclined plane, at a constant velocity of 6.0 mt 6j-wosd9/goj9qark-.mi +v /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 dth45- j*pu ssi,fuqvu7; l.laown 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 rougfk 2;xfjq0y1p :bq ,noh $37^{\circ}$ 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 alon8g( jgdyhx z9vv9;q c*wq)8gfg a rough surface. The cable attached to the l9x(h)w fvqdv98q*cgg yz8; gj og 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 t 8:wxrbxxpz-.(54m ue2 wxzn zilted at an angle x-5nwb(2zu z xz:xp rwxe8m.4of $33.5^{\circ}$ 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. The anglnhie a-rvjhy- v:)n:orp 0j*d py u36(e 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 between6-d j 0:)pyvoj eh-ar ir3hyp(vn: u*n the object and the plane?