Which of Newton's laws best explains why motorici((fro-i k,q sts should buckle-up?

  When you sit on a chair, the resultant *4)z ,oa6dcshmui;u zforce on you is

  In the absence of an external force, a moving object wi,m(qz ;rot-5 4uuqg 4 mpgkez0ll

  When the rocket engines on the starship NOm ns12cj)kte9 -PAIN-NO-GAIN are suddenly turned off, while traveling in empn9j 12) sektcmty space, the starship will

  A rocket moves through empty space in a straighd m26 i0hbp:2pzt3 xsvwg5+k ht line with constant speed. It is far from the gravitational effect of any st50t ib d2:gzvmxh+p 3hskw2 6par or planet. Under these conditions, the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you*7go)e2tpr 0o4r k:klpzww+u suddenly fall forward. lg +ptwz r0e4w2o*k7ur po:k) You can imply from this that the bus's

  You are standing in a moving bus, faciatv-h0 u 4(t jwk5 j:tebz1i)8dkz1emng forward, and you suddenly fall forward as the bus1h ikt db ve(aj-5)jz840u kw 1zte:tm comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objecu1w6j) on.px gt.

  The acceleration of an object is inpp s/dhjd2(5b 6e zqk+ iz9z ot;uu*1bversely proportional to

  A net force F accelerates a mass m with an accztiu7cs;;5i r7j x m1tc .,cfpys -t;veleration a. If the same net force is applied to mass 2m cis 17;7cc;t xtjtf5;y s,pmi.r zuv-, then the acceleration will be

  A net force F acts on a ma 4/:dju3t zak2wr1wbou-lk; ess m and produces an acceleration a. What acceleration results if a net force 2F acts on;1jk2-wu/tu kewob:zrad 3 4l mass 4m?

  If you blow up a balloon, and then releaj-8 p :uq stw0 efvcjc6)x*)rgse it, the balloon will fly away. This is an illustt8gfq c :6jvce)r*s )0wjxup-ration of

  Two cars collide head-on. At every moment during the collbd40m0 x+dkdkz buemc jea7o5l, )a,4ision, the magnitude of the fo+) dok0 x e4bld0dm4a5z,bak7j mceu,rce 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 example of

  If you exert a force F on an object, th2n3l 4zgu5karlvo53 8xuuzzfk5g1 g8e force which the object exerts on you wiuak83l z55rz315gugko4 2 v8xun zlgfll

  Action-reaction forces vq7ej cv09q2m

  Action-reaction forces arno h/; t.ruquxcwb0a o(q0e;jm(xh14 e

  A 20-ton truck collides with a 1500- k,0e:1pr(dpk ldor t1 mhl(7clb car and causes a lot of damage to the car. Since a lot of damagkppcto,m0(ld hklr17e 1:d(r e is done on the car

  An object of mass m sits on a flat tnm5 2.r od)mkqable. The Earth pulls on this object with force mg, which we will ca 5nqm)kom2.rdll the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of aec ,nd:jil-ia6r.l 1y+(k fnm string. The Earth pulls downward on the toy with its weight for1,k mc + i: jfl(nl6reandyi-.ce 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 insta,6c+njp k: tswntaneous force. The ball hits the bat with an inc twps:nk 6,+jstantaneous force, whose magnitude is

State Newton's three u-k nj*y)j,1 ccl tph0laws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon th)4djcld iz.9 oygro g e2y6)l3an on Earth. Which of the following is true about the mass and weight of 6ggji2r. 3zeoc 9)o) lly dyd4an astronaut on the Moon's surface, compared to Earth?

  An example of a force whiche j t4ey)9wg-(. ormz--tq1ec5arbzq acts at a distance is

  Who has a greater weight to mass ratio, l25,jp1w ghrfa person weighing 400 N or a person weighing 600,gw521jphf l r N?

  A stone is thrown straight up. At the top of u/iaijr, (f2 26wsmyd its path, the net force acting on itsj(2md/ ,6iywfa iu2 r is

  A 20-N weight and a 5.0-N weight are dropped simultaneously frmt.b 6 k)lsx97pp3ke oom the same height. Ignore air resistance. Compare mko .b) xks37pet p6l9their accelerations.

  A brick and a feather fall to the earth at their respective terminal velocities.v8qr 9u8 4 5gatnjprw5 Which objectr4qtgv9pu nj85 a5rw8 experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elev vr1ps n:p3zj/ axl*1tator. The elevator is moving up at constant speed. Wha:3l/x p1j* v1 rnptzsat is the tension in the string?

  An object of mass m is hanging b. 2;biwc)c: b6dhdps8 qmzf4 oy a string from the ceiling of an elevator. The elevator is moving upwsz2cb d)fd6wi:h 4mqo;8cpb. ard, but slowing down. What is the tension in the string?

  The force that keeps you from slio; . 8lur)jiidding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from jn3 lav 239lfvm+ad4 qrest than it is to keep pushing it with constant +qfnd 2m a3j4lva9lv3velocity, because

  A horizontal force accelerates a box ;bm qt;1hh6 thfrom 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. What happens to the boh;m hqtb6 th1;x's acceleration?

  A packing crate slides douje:z .x0ntu( wn an inclined ramp at constant velocity. Thus we can dedje 0u( nzx.ut:uce that

  A block of mass M slides ,gdj9u 3.o -czk5+ujoat4m gudown a frictionless plane inclined at an angle q with the horizontal. The normal reacu .g-, 3k4ucjdmuo goz5t 9+ajtion force exerted by the plane on the block is

  A block of mass M slides d5 bzuhbg a948fsx pfv2f1 ia87xbt9 +cown a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exertf5 ixf72 ph+tf19u4bvb8a8sc gaz bx9ed by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an an)c*jffgi0w. 0+vci il9e -l oogle q with the horizontal. The gravitational force is lico)g.f lij+ 0v9e fio w*c0-directed

  Two toy cars (16 kg and 2.0 kg) are released simultp8xrlma ,5+ icm:ib6e aneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being mix,m6 i5rplcb+a e:8released.

  An object sits on a frictionless surface.3h 0(;uga ndfa;qf y,f A 16-N force is applied to the object, an, ;u0qdg3f(a;ynh fafd 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 ingj pb3 (ixzvmh t sr0/4s+/9jt 7.0 s. What is the average forward force on the cat /v 3r9+mjjtib4gspsz/( xh0r?

  Starting from rest, a 4.0-kg bod x fqdpp1,:,rj n iha;8)fbl4fh+r) sjy reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on )p+sn1jdxfa 4l qhipfr8b ,):hf ; ,jrthe body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m1e:p zvb jb+(62k9t(cou nwcy/s after traveozjk b nep (+:1( 2tubwc69vycling
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 mg n-6zn;aa/ dtsrh3/zass from res/rd tngzhn;3-za 6/as t,

  What is the mass of a9po,wac2a 4p wq ple24 person who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface oyt2 *a: nhfb92gefb.vf the Earth where the acce: atf.g9vhbe2 f2yn *bleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg onh( c2pll92h *+lds gon the Earth. What is the mass of the object on the surface of the Moon where the acceleration hs2(+9gcdno plh* l2ldue to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, anap v,3d,i gmdb ,99nzul)z p0ute-u;fd object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Evn3-,9miuud,;z9p0flztapg , u)be darth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on oppo+:e0+;duxrwl frm 5+di)dp arsite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope acceler rd r)0 :dw+iuml;+redax5pf+ates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level fri1jsn 5oygy*bl hgzb9 9l,l5h3ctionless surface. A force F acts on the stack, and it l9gyl59hgbj l nz15s*3bo yh,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 N stands on a scale (trzrykl/0lumr(4q00fb0igf9 h q.din an elevator. What will the scale be reading when the elevator is accelerating downward atk(by9 gq40zt0/ufrl h0mr0dqr if(l. $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person isl 76 1jzog)wkil0hx3e 60.0 kg a30 lxl1hi)7 ojwzeg 6knd the elevator accelerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in a+ c*: gajaos o(nh:w5en elevator. If the mass of the person is 60.0 kg and the elevator acceleratahae: s*oj5+:ocw n(g es upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a a t )jabf+ hzok h/77 m.k4buqqnu323p5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magj4mkpa3foh7qn+ 7. kz) uu2 t bhqba3/nitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests o cw55 ;3: m. v5vb.vz x suadsc8uo+u*aiitwc*n the flatbed of a truck. It is held in place by metal brac3od+c5.uwu:z58 xv *.i aavtuccwv sm;5 i*sbkets 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 in place*9sa jer .9ubh by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 15 m/s, whb9seu.aj*r 9h at is the minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine sloa2 /i4* aar2n;un irhown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude /urn*o224 ialn aa;ri of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Figudwu:jy3b(nzg6vhi40 vmjgh 4; z2, z. 4-1, if M = 0.60 kg and m = 0.40 kg, what is wbz (d,ghiyjzu4 u0;3v6n4:h2vz jg mthe tension in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of r+*7c md t2ulabooks on a smooth horizontal floor with a force of 100 N in a direction of +7c m2ltr*ua d$37^{\circ}$ 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 bmxpdkdk**(3a wx4h:r ooks 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 bdm 4w*xkh* :r3(ax pdkooks is 40.0 kg, what is the normal force on the box?

  A traffic light of weig6y(v n*uj:)cia3zq omy1i xu43h scq 9ht 100 N is supported by two ropes as shown in Fig. 4-2. What are the ten3hx)jm96aiios4 u nuy:cq1 z (v* 3ycqsions in the ropes?

  In Fig. 4-2, if the tensions i7k3uzl ca p:7in the ropes are 50 N, what is the mass of the traffic l77lkaiu: zc p3ight?

  Two boxes of masses m and 2m are in contact with each other on a frictionless 0 h3ocgw 1rxk5 1tmew0surface. (See Fig. 4-3.) What is the acceleration of the h kw5wtx11300gec omrmore massive box?

  Two boxes of masses mq- .yuzy,arl5 ny-,hk and 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force on ,yk. -rau-,lyn5 zq hythe more massive box?

  Two boxes of masses m and 2m arej fszzf:7/uhrqv0y02 connected by a rope. (See Fig. 4-4.) If the forward force on the more ma2q 0zr7yf fhuz:/sj0vssive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a ropeyr*ohg:5cq*w)fny n p )bs2 h0. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less massive box?h qp )f5hn)rs0 c 2yb:*oyg*nw

Two boxes are connected by 4s0nlt6q s3x w7eqh9u5 rz9bna cord running over a pulley as shown in Fig. 4-5. Box I of nht9qsqr40e 9wz s7x3 ub56n lmass
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 r,+)v v2 hlxgaare 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied tlh r+vv2ag, )xo the box?

  The coefficients of static and kinetic frictionsqeb+5*b nq.z3ovr e2h for plastic on wood are 0.50 and 0.qe b. zonh+*5 3eq2bvr40,
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 omv;8/lwayc71:qj1 lpjt 6xoslows and comes to a stop allc7j8xp1ow6oqjv;m y 1t :/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 horizontal surface is pulled by a5qy4 kj94n8f/y5c lohmf eo; u 5.0-N force. A 3.0-N frictie5o4nj f/o kyf9y4cu q85;hlmon force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, froiacoazr,:y* / m 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.ugbwn7rqx-wyy( f20 mq3e*9o It slides 50 m on the ice beq0ux2 n39oy - 7bfwgmw*qey( rfore it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks 90.0 m l7e km3 s8j+oe sg+w5wuong. They determine the coefficient of friction between the car's t++geom8s5wj s wk7ue 3ires and the roadway to 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 stacked. (See Fig. 4-6.) The surface betwe snrsp 2x2p pe+7dg42nen the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less m4+gd srxsn 7 p22p2enpassive 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. 4-6.) The surface betw0eelm726 wc99- ez znxtp 4jtpeen the more massive box and the horizontal surface is smooth and the surface between the e -9centtp70zpzjlex6wm2 94boxes 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. The plane is inclined at ayiz 8x fr;vymgw0nio.9x +0o/n anglen o 90x+0.y fm8v/ig owzr;yix of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that 9,c i3 fo m51ykzzm9l. krpx0omakes 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 inclo+3fiu *wx zbi6q4y:hined 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 inclinta;/xjm to7wf5-vb 8q q 8pzl8ed 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 v/x5c t*. yookzelocity ofzto.k/ 5oy*cx 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 sli9xf zjfu nx*a:r 2f:3zdes down 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 m9 q3 toky7e7vf slides 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 cableuv:s8k6j 6 txp attached to the log makes avx :k68jpus t6n 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 how..s(;ld1vsy l8dko54fwp angle 4okv;py.8 shl.ds1 ww5lof(dof $33.5^{\circ}$ 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 inclivkw(pl+:h5s d6 x6kc ined plane. The angle of incline is gradually increased until6w(idcxs5+h:kv lpk 6 the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?