Which of Newton's laws best explains why motorisz038yqldvn0nfmrtu cp - u18(ts should buckle-up?

  When you sit on a chair, the resultantw *.w7y.o /gi:m. k tg hqogjz;yh;-rv force on you is

  In the absence of an 878u9yp qzy8lwas/j oexternal force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO utb3q5r gccbiq4- nob:2;3v m-GAIN are suddenly turned off, while traveling in empty space, the stars:qbc3 ;m5nio b4r2cu3-bvqt g hip will

  A rocket moves through empty space in a straig h/d,9 s(p/oy7ps:g szy) y-9vmlrxx bht line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must y9:7/rbdsy9xgxzps( - vysm l ),oph/be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenlpn 9iyi+ u4,nn ,1hupdy fall forward. Y9pnyn, i+uidh1u4n,p ou can imply from this that the bus's

  You are standing in a moving bus, facie o gmxh30y 1h)5m-uygkg; w,eng forward, and you suddenly fall forward as the bus0x31 mewg)y;-oh ,kegy5 mugh comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe t1 kz5xx jvc*a3he motion of the object.

  The acceleration of an object is tn8upb. zecon5yxa/*f*c)y. inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net forcug7;ru ya5d8ott+ js )e is applied to masrauou+ d5g 7;stjt) y8s 2m, then the acceleration will be

  A net force F acts on a mass m and produces an accelerationr/6me.c jk ,pzmix/1i a. What acceleration results if ai c/i.6pxj mmk1r/ez, net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. This cby nm(q.fg*o pa9er9 y+(9jffc+*.n( r9bajey qpm( o99 fgyis an illustration of

  Two cars collide head-on. At every m ;m 1s)ybokjbp 3 9eyak(prg)lg0emf3c12d, doment 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 a(jmeo rb)3)ypkb2pg9k0e l d 3y ;sgc,fm1 d1the first. This is an example of

  If you exert a force F on an object, the force which the object exerts on you wi5rm5kcesa6m6 s+s + uill s m k+6i56sr+emc5uas

  Action-reaction forcesezxa-olh g/7i o(/ 2xp

  Action-reaction forces a cumskx y/6,:f s4hghsv ,1 vxwv)mo1:re

  A 20-ton truck collides with a 1500-lb carvu/ovw kik 9nj3w i:cv1 j)h*przdjvn71y/.2 and causes a lot of damage to the car. Since a lot of damage is done on tp vnvi :w/vhk jivu7 2jj .)3n*c1r 9odk/1wzyhe car

  An object of mass m sits on a flat table. The Earth pulls on this object with r 6lgv f / nczq:jp+)43ftznp5*iqd+ fforce mg, which we wipfg *di6n clqq5z+rpv 3/+t:4j)fn fz ll call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. Thd-qjr ncvw,3 7t41 ihde Earth pulls downward on the toy with its weight force of 8.0 N. h7i ,c- 3nt1qr dwv4djIf this is the "action force," what is the "reaction force"?

  Your bat hits the balq; i* wahny*dl6(1qh omf.g1tl pitched to you with a 1500-N instantaneous force. The ball hits the bat with an instantaia d6yq1wfon q;(mg.lh* * h1tneous force, whose magnitude is

State Newton's three laf) 4/: c5yhe: oailryf -swczei-2ca0ws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. 7e;erxr/ q( wuWhich of the following is true about the mass and weight of an astronaut on the Moon's surface, compared tor;erwe q/7xu ( Earth?

  An example of a force which ac p8ncylli4js7( 8f9ib ts at a distance is

  Who has a greater wei khnz6;(37goop +dy hzght to mass ratio, a person weighing 400 N or a person weighing zzg3;kdopn(hoh +y67 600 N?

  A stone is thrown straight up. At the top of its path, t3cwp3v8lnfo7k8 uz 1 the net force acting on it ipftn8z3 l8vu7ck 13 wos

  A 20-N weight and a 5.y4xkvtkq m7 5b0 fle:.0-N weight are dropped simultaneously from the same height. ekmbq 5:0kyx4v.tlf7 Ignore air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective pwqof2o8amlow:cc.(5 -ll+ x terminal velocities. Which object experiencea c82c. l mwq5olf:w+p-x (ools the greater force of air friction?

  An object of mass m is hanging by a string from the cx,vldke;8h,fn pq9f3 b s7m28l0vfz ,m+ixiveiling of an elevator. The elevator is moving up at constant spee x f silzn2fi7h+b,v8k md,ve;qx9l 30p,8 fmvd. What is the tension in the string?

  An object of mass m ismq tgv)t;f/ ,y hanging by a string from the ceiling of an elevator. The elevator is moving u ,/)ft ;qtgvympward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidew9(b6nj draph 3a0xi )2pby4tialk is

  It's more difficult to start moving a heavy ca c c l,;lhot+s/2mq:x 3ctasz;rton from rest than it is to keep pushing it wim xo,qtlzs;/ch+t;cl ca 2s3:th constant velocity, because

  A horizontal force accelerates .(x .sgsxu8yz a box from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all coxu8( g.ssyz.x nditions remain the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides dowx-:pfov9*9jdt4)ke ug tfe h8n an inclined ramp at constant velocity. Thus we can deduce thatgx4k:f8d)uvho9ee ft *9jtp-

  A block of mass M slides down a frictionlr - b;vvszn6;7 byeok/ess plane inclined at an angle q with the horizontal. The norm v 7kerv/;-o;yzs6nb bal reaction force exerted by the plane on the block is

  A block of mass M slides dc shj 91wi:xlg.kn-thj 5*/iqown a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block i-cltw*ki5j:jgh/qxs .h9 n 1is directed

  A block of mass M slides down a frictionl-cd5 9zp:dqa5/h, wsx lnw pr5ess plane inclined at an angle q with the w d9 nasqdp-zl55 xr,whp5/:c horizontal. The gravitational force is directed

  Two toy cars (16 kg and 24-8 *hthxn hi8 caf7ib.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a stchtanb4 8ifh -i8 xh7*atement which best describes their acceleration after being released.

  An object sits on a friu .w.g3sw9rtv ctionless surface. A 16-N force is applied to the object, and 3 g.9uwwrtvs.it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerateduz0ne qx13g l4mta7 1 from rest to 27 m/s in 7.0 s. What is 4udx1 l z enga1tm70q3the average forward force on the car?

  Starting from rest, a 4.0-kg bodyge,1b spe,ik n+) shz: reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting o 1ks,,ei)hegznbp: s+n the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a 4zvgowk f13 1ky,6wycq6 c9dhspeed of 50.0 m/s aftckh6wczwkv, q1 4dgy96y fo 31er 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 txsr xf3* lb8t: 0xo/pahat you push a 10-kg mass from restx /ox f a3br0tp*lx8s:,

  What is the mass of a p 7r* w/hux u0.d03ax4cxsfsd0)su mck erson who weighs 110 lb?

  What is the mass of an object that ww s50uft;1*ks t+j nxzeighs 250 N on the surface of the Earth where the acceleration due to grj0xst+ nkwu1;*z s tf5avity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What .ftpo +wmat (x0j/(nwis the mass of the object on the surface of the Moon where tw(t/m0 pn.+f(xwtaoj he 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 opal)oa8lj(8f )ddwht e*a6-n n the Moon. The Moon's gravity is 8a6hnf8 )) laa(tojp*dl-ewd one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a t2c 6/gj-dyfh jug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. Whayj f 6/2jdhcg-t is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F - pnve( eod.68ncl 7feacts on the stack, and it acc-8vn(eno .el6pdcf e 7elerates 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 onofo-s sdl 9:l+ a scale in an elevator. What will the scale be reading when the elevator is accelerating do:ll+ss9-food wnward at $4.00 \; m/s^2$?

  A person on a scale rides l1heu*zl x2, ;+po i,emswps (in an elevator. If the mass of the person is 60.0 kg and the elevator acc pxul2,moi*+ s1z ,wseh(;pe lelerates downward 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. If the mass of the p(iuef,4bg4 jv y8i/zo erson is 60.0 kg and y/ i 8ubvfo,jzi4(e4gthe 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 mass. One force has a magnitude ofb:8 cl75yvtmt8h 2nzole.r +md.rkf. 8.0 N and is directed due north. The second forc8vf5e.to8brktd: ml. +m cz.hrlny2 7e toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of i gqju +5: ecv.6sra87(h mtzra 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 if the load i5jt(.s8g7zq+hmi uvrc:6 r ae s not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in plagz +rvor 9.ojphs )7x4ce 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 time if the load is not to slide forward into the cajr9s vxg. h)p+oz7r4 ob?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, qk 0ec7 jh:dh*what is the magnitude of the acceleration of the system? (Ignore friction and the mkh0dhq*jc e 7:ass of the pulley.)

  In the Atwood machine shown in Fig. k-knn), g urag;g-b0h4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pulleyugnkg b,-ng -0)kh;ra .)

  A student pulls a box of books on a smootq hsf xq 1wc.f* ;2/rj/st3lkfh horizontal floor with a force of 100 Nctw.f3*/qkqfsrlf; 2s/ 1h xj 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 force of 100j,j7km(,u2qc c7oaux N in a direct qk(amo j,7ux7j c2u,cion 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 we+o)ute4-r,yb6dxqqq( v a7;ug kro 0iight 100 N is supported by two ropes as shown in Fig. 4-2. What are th;gouy6u0qki +4rd-xte qo q7vabr,) (e tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes a qvdf --r.edi7re 50 N, what is the mass of the traffic light--7idv.d qefr?

  Two boxes of masses m and 2m are in contact with aio6n. e4w; jkeach other on a frictionless surface. (See Fig. 4-3.) What is the acceleration of the more massi wn6eok ;4.iajve box?

  Two boxes of masses m and 2m are in contact with each other on 3srcrfxfo3) - a frictionless surface. (See Fig. 4-3.) What is)rr3o-s fxcf 3 the net force on the more massive box?

  Two boxes of masses m and 2m v i;blz2 ez075 krp/qvare connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in 5 zilq/ve;p0zb7krv2 the connecting rope?

  Two boxes of masses m and 2m are connected by -p p3rur+h)/ ;ri amsha rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleration of the less m )h;as-3mr/+ upprr ihassive box?

Two boxes are connected by a cord runjc -sys c3q w.)zxm4b3egfb9*ning over a pulley as shown in Fig. 4-5. Bsbe3m) cgw3j-. 9f4 xbz*yqs cox 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 and kinetic frictions betwej16vokrtql zvm9:1 o(di1 *lx srj a(8en a 3.0-kg box and a desk are 0.40 an1xi8(d q la(vmkj z6r:jv 91*1olrotsd 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on woodvicgq+ 2 xnb s;dwc,x( ,;qz8y are 0.50 and 0.40;x d,vb;gyxw,2c(q iz8cnqs+ ,
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 slows and come- lfa/f,8lgfr s to a stop with a constant acceleration/lffflgr 8- a, 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 njh27iy 9 hi26x*fr twby a 5.0-N force. A 3.0-N friction force retards the 679ihnhx*jwyt fi 2 2rmotion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerst bps vh2bfq)qd9./- ates 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. It,ru rzm m wm)2v5es5;b slides 50 m on the ice before it stops. What is the coefficient of kinetic friction betwem5,);u s 5rvrmmebw2 zen the puck and the ice?

  During the investigation of a traffic am4*qg5f ooam;ccident, 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 form;o5 ga of*4mq 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 be qw of507s2x 8u-feadstween 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 ssu-e7fw 0daq85 2xof 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 betwzu 0sr v,no z(4nqbbpr1:a,3eeen 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 coefficient of static frictzrb4 bnnvea10(spr,u3o, q z :ion between the boxes?

  An object is on a frictionless inclined plane. The plane8 7gbnpr*cwl 8 is inclined at an angle of nbgpl7*rw8 8c$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat halt,d 6w ;kgf1g5lei/1sv.mg ill 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 apb f,2+g5 x6cj ky*xhsmooth 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 an anglef6x:eb )jeg l8 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 velocia *cgti3dnk tr) -bnndxr-6)0ty of 6.0nd3b-gi c r x-*n t)kn)ar06td 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 slidest4y5u+ng 5mgcy cn*,p 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 m slides down5n fgfm4y xid7rs:;d , 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 rougd se/trefyjc 6,r796u zav8 3jh surface. The cable attached to ue7/vf,8d t96jy 3zres6j ar cthe 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 -r) 7wcjazr:qnza z,284 icua s5:dirplane tilted at an angle ofqj) -4wzr rz,7aza uscd8cian5r:: i2 $33.5^{\circ}$ 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 angle of incl. a*;n2lqhj 0cax9op kz (d)kiu/v5smine is gradually increamq.u*5a/2 );hs 0 dzkxlc(ink povja9sed until 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?