Which of Newton's laws best explains why mo( ynz2 m--b))z ghoefttorists should buckle-up?

  When you sit on a chair, the resultant force on yoiqdcwf9o2x 7*4 :z4vdy8: i vp;jmybou is

  In the absence of an external force, a movg4b n):b*+dpn3n y vuxing object will

  When the rocket engines on theo :86ljnk ( wi*cgrbnb:wzlw/n)b:+k starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in6z(bbg :n wcl /lr8 w+ko *nkjb:wi)n: empty space, the starship will

  A rocket moves through empty space in a straight line with constantw9qiv5 d orf+3fpqn (8 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 sustaivqi+f5nq38pw fd( r9o n its motion is

  You are standing in a moving bus, fab l * bbag1r9xo66:zgwcing forward, and you suddenly fall forward. You c1lxggo6a z bb6 9w*:bran imply from this that the bus's

  You are standing in a moving bus, facing forward, and youg,tmdv6t t. a. yfa(s) suddenly fall forward as the bus comey, tgt)a.t sadm(f6 .vs to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the moq2 6a3bo)ma+ b2l xabetion of the object.

  The acceleration of an object is inver.yxj yvicn;52l 7k xkk231hn fer:a /msely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net l.c k lj9lzm.g3n9+pc force is applied to mass 2m, then the9zpng lc+.cjl3.9k m l acceleration will be

  A net force F acts on a mass m ajq 3favb)t yd.; bctu4iz)5)dnd produces an acceleration a. What acceleration results if a ned5d)bi; 3v 4jtcz.)yqu)tabft force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balls xxe3uxxau5 8m907v soon will fly away. This is an illusaeuuxms 05 x3v79s8xxtration of

  Two cars collide head-on -q.ykaabg8f7 . 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 the second car exerts on the first. This is an eqf8 bag-ak 7y.xample of

  If you exert a force F on an object, the force which the object exerts on youk;ya+ddkt yr/c67ro 3 wily7r ykota;kr+d63d /cl

  Action-reaction forcesmzm:3 lz.; h/:f*dl02myp8s pi wkjav

  Action-reaction forces a lxui (-3o+v9odch6 zbre

  A 20-ton truck collides with a 1500-lb car and causej(vjo- u,s def5 ;la3es a lot of damage to the car. eo d(,j 3ve 5;ju-aslf Since a lot of damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this object wrhh dc9 q/hl4zbf6h d28 )gv7uith force mg, which we will call the action force. duhghhr7)v ql64bhz2cf/ 8d9What is the reaction force?

  A child's toy is suspended from the ceiling by means of a ,5ae0h ibxks8gk)(njstring. The Earth pulls downward on the toy wit5g,bj ikhek80n()x ash 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 instant1l 38n dmfw.a7bknv v*aneous force. The ball hi. mnb3*1nwka7 dvvfl8 ts the bat with an instantaneous force, whose magnitude is

State Newton's three kwvwfaw ; 7k g7zd1(i8rf1fnl.:qsn 2laws.

  Mass and weight

  The acceleration due to ga hm u9)d*ha,1vz gu*dravity is lower on the Moon than on Earth. Which of the following is true about the mauahv1 dh9 * guda,)*mzss and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distancn3/novtsi /)wh .-fiu e is

  Who has a greater weight to mass ratio, a person weighif5:rn:l g i6er2x7pj1g m:unpng 400 N or a person weighing 600 N?xpnr::fl576gm2e1g pi:nu r j

  A stone is thrown straight up. At thef+ (xeyk7 yzo6(phg w: top of its path, the net force acting on it :hyzg((y67of w +exk pis

  A 20-N weight and a 5.0-N weight are dqwf6t8d 5xxcji6 ak q0cl2:3eropped simultaneously from the same height. Ignore air resistance. Com ck2lq6w6eadxf0c:t 5 3iq 8xjpare their accelerations.

  A brick and a feather fall to the earjak;w2lz b /j4th at their respective terminal velocities. Which object experiences thelj2bkw4/aj z; greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of;:bb yqd;2dna an elevator. The elevator is moving up at constant speed.:bn ;;d2qdayb What is the tension in the string?

  An object of mass m is hangi*7j5 9 sxfi u8t4sxsypng by a string from the ceiling of an elevator. The elevator is moving upw5f78i xsjux*sypt4 s9ard, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidewalkx ydocd3a/b5 ( is

  It's more difficult to start moving a heavy carton from rest than it is to dos z 9l1+z8)a pp32spht*rlokeep pushing it ws9p+*ozhazp) lrsl2pd1 83o tith constant velocity, because

  A horizontal force accelerates a bof) z9g uj0a50l5 1n7 sktqdhbax from rest across a horizontal surface (friction is present) at a constant rate. The exp buhqa0 0gkna5z)7ls19td fj5 eriment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an0kk9bhqz* rhc: 98k cq inclined ramp at constant velocity. Thus we can deducec8q0k9bh*9 q:hk zcrk that

  A block of mass M slides down a frigug j; ny+o e7 /u:4elg8xmh6vctionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block iuejg:gmn6h x4le 7 u;v+/g8 oys

  A block of mass M slida8x1fz6sc vier8xi yz/ 8.m 1ses down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by i/z.r 1ax6vc8z8fm 18 xysiesthe plane on the block is directed

  A block of mass M slides down a12z za)d s9nmu frictionless plane inclined at an angle q with the horizontal. The gravitational force is directeaz ndu)92smz1d

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on y5ky(81t3bm 1hk xuvs an inclined plane that makes an an8 x5y uts(ym1hk1v kb3gle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless gj t; +g5 v*i4gxy*3 masno+vswe4o 3nsurface. A 16-N force is applied to the object, amnn*4 y5gs ;ae4*gxi3 joo+w vstv3g+nd 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 resh 3k5a o0jcwl4:3vxb kt to 27 m/s in 7.0 s. What is thex330kolj5b 4k cahv w: average forward force on the car?

  Starting from rest, a 4.0-kg body reaches a sq2jrf or qy+)tg*j m66peed of 8.0 m/s in 2.0 s. What is the net force +mfrr66j2 q yogq *)tjacting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a svx fx( 9r( g1yw w6e8sactw0s6peed of 50.0 m/s after tra( cxwgt vr08(syxa6w 9f1 we6sveling
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 y2m+glic;b,pu0w0 m(ga m18lm3toyy j ou push a 10-kg mass from rest,wt jpyc gmibl;0 g03m(oumy ,1 +lma82

  What is the mass of a person who weigx3fkx .ooj+uefv-as fh 8 y*2/hs 110 lb?

  What is the mass of an object that weighs )t(rpp hv/l6dem :y, c)p gg147btd xa250 N on the surface of the Earth where the acceleration d)6bd(ha)tp/1dc7 emyrl gvx g,:4tp pue to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earthykyy5 c0z g +(yw3xnr,. What is the mass of the object on the surface of the Moon where the accel nk3+5r wyy0,cz(xyygeration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on E2y05t afy rsf+arth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of tyrf0y5f 2s+ta he objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends xx 6;r n j* mkhquv(;(kqrf8;fof a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope fu6m ;jh;xxfk (n qkq*8;rvr (accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionlessvmv*e,6ox4d rpz78er surface. A force F acts on the stack, and it accelmz 68*v7 or ,d4repxeverates 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 s,f9t/i dd cod)tands on a scale in an elevator. What will the scale be reading wd,t)oc f dd9/ihen the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60n :9fvzrm1 2ao.0 kg and the elevator accelerates down 29mv1nz:ora fward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. I 1,xi bvc*)mil ziyp82f the mass of the person is 60.0 kg and c)pb8imz ii2v*x l 1y,the elevator accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forceliihhx)14qwz-9lx p,j lj:u (s act on a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east h1uiwj(hq4 jxzl)h :-il 9 lx,pas 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 is held78mfc)sytyo5l k *j0t 6sgl5f 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 tjgs7yscyol8l 05ft*k6 f)5mthe 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 in places3j1 b xucu+ldzk y)w +w t1+tp-g6g)x by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, whp)wtct ubj)ksdl6 w+g+-x gx3 +1y1zuat is the minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-69tqtx z8) f9x9b ssqxdju 4-uywcl;+1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ig98 ;x-lb + z quwxsfc9q x64t)du9tyjsnore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if z/tbr,c dbgi kr5(3*d+r n6ppM = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the r3b/g(,tcn rbi56dr kpz +dp* mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of,95g4t d b0nw(nxqs lf 100 N in a dir5 f0nn tq(,9sg4blxwdection 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 oj,)o7suhg:mfe + 5pw sf books on a smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the b7o je)fgw:supm sh, +5ooks is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N )-p0qusb mbvc 9g;5cv is supported by two ropes as shown in Fig. 4-2. What are the tensionspbgmc)b-qvc95;u v0 s in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of them 8u1l8cjw d5t traffjut8w5 1 m8ldcic light?

  Two boxes of masses n ked rt0w;,8mm and 2m are in contact with each other on a frictionless surface. (Semt8;,k nw r0dee Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with eaiaeaj g g. 3nl.m;:ld2 ml mos+4p:+xech other on a frictionless surface. (See Fig. 44+a s;eg.olj l:ilndxa 2me . mpm3g+:-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.) ;c;p*4ui 5s( mql xvpyIf the forward force o( q v x5pmy*sl4;u;cpin the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a ropb8,cok/ n+kh b*f4zvpe. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less masobv8h*4k+/k fnzc pb,sive box?

Two boxes are connected by a cord running over a pulley as shown in Fw am mcz5m*xmy u9px:;u5i2u6 ig. 4-5. Box I of u5 i*mxuxmwz5am 2m:;96pcyu 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 kinet:uy lf1)eju2f ic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net f1f:2y)uef jlu orce on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for pla ym)ng:rdv:dt1v9o )rstic on wood are 0.50 and 0.40,: t)m)r1g9rd nvdy: vo
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 inpn x-nvz ig rfuge1z*n5y8d7*4s4j8 w the +x direction. It slows and comes to a stop with a constan7g-*z4e5x*g8 1 8fu w zyvsdnpnn4jirt 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 horiz e0-)htitww j-ontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleratione )- 0ti-jhwwt of the object?

  A horizontal force of 5.0 N l-3 jhn*ut19 pgfwenri14b 0o 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 10d; jv7nw 8zv(n m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck a8v w;z(jd vnn7nd the ice?

  During the investigation of a traffic accident, police find skidagm. iqa6/-e j 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 the speed of the car when the brakes wer am/a.jeq-ig6e applied.

  Two boxes of masses m and 3m are stacke:wclj l2 2p,sid. (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, wh cis,l j:lp2w2at is the static friction force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6d dxxm,/:bvj:.) The surface between the more massive box and the horizontal surface is smooth and the surface betwdb mjx,dv :x/:een 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 frictionless i:26 gu b4 lowi/gt4jzjnclined plane. The plane is inclined at an anglt62w 4jg o:jl4guz/bi e of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that ma orcf( ;ts, *)1a90roumyxckvkes 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 s -au; q5 yvtyb-(9xvirmooth inclined 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 plane tilted at aq wuwxt5;- 1p2 ahr8mmn 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 velocity ofr dyu.zbe 14* m g6g5ss nemy-t49nrg8 6.0 m/s. meye9-1*tnggurm5b4r y6 sg4 zs .dn8
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 rx.wpi8 ywz/; gough $37^{\circ}$ 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 dsl4*:; ktyt;7ed x cwuown 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 weighinggewla-jtv 1.ll dn ;u)4*ul6a 500 N along a rough surface. The cable attached to the log makes an angld-j6l ;w*te1lunv g).ll4 u aae 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 ;7 45et7c+ook brqupc from rest on a rough inclined plane tilted at an angle+ pcr7 t 4;boock5ueq7 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. The anls / t:9lorw/ 6b7xyzxgle of incline is gradually increased until the object begins to slide. The angle at whicrt/xls9y o7wbzl/ x:6 h this occurs is q. What is the coefficient of static friction between the object and the plane?