Which of Newton's laws best explains why motorists2wa .miunel3/ )ma)g s should buckle-up?

  When you sit on a chair, the resultant f2je,r8gx(ct +nk9.o rd5 nevh orce on you is

  In the absence of an external force, a moving ob 3(bodh5jw0kkj 0db2bject will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenlzjg;ywtrw.ca 24 d3dlh -4o 3ry turned off, while traveling in empty space, the starship3 zy dtr-;g3h4d rjwa4.owcl 2 will

  A rocket moves through empty space in a straight line with constant speed. It i si+5aj(ua (cys far frojyac+i(s5 u a(m 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 is

  You are standing in a moving bus, facing forward, and you suddenly fall forwardf zgb)zq2 qc83. You can imply from this that bzcq 3gf82)zqthe bus's

  You are standing in a moving bus, facing forward, and you suddenly fall fo gli ,d7*yrdcm1-eq, vrward as the bus comes to an immediate stop. What f gl7vr qyd*,md, e-i1corce caused you to fall forward?

  A constant net force acts on an object. Describe the motiripw,n 9eg k4)on of the object.

  The acceleration of an object is inverse f,x;7 i8cg*2jbmb qlcly proportional to

  A net force F accelerates a mass m with an acceleration a. If2-lkd)5ncwo /ozq1l5xvg ; nt7 wtk6y the same net force is applied to mass 2m-1c ko2 5;ldwzn nlo5g/ tk)67tqyvx w, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a.oi+hs 8n5ydx o. or6z4 What acceleration resur5 o +hydz8si6.no4ox lts if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. wzi1ju w(/1)6zjag uz This is an illustratu11iz/aw w6) uzgj(zjion of

  Two cars collide head-on. Ap/w39pd9(xcqcn vj5z dnr 39d t 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 v z3d d99ncn3dwpx pr/q5j9 c(example of

  If you exert a force F on an objecdx(ir2yy k5rh 1nj;3agl5i0pl a u/ e,t, the force which the object exerts on you wil lj 5, h/rya2p d0rkxenaly5i1;(gu 3il

  Action-reaction forcest (z,:f.nuc0j hnctw3o /i*x b

  Action-reaction forceaxp)x9-kw(1 6fqrbmrs are

  A 20-ton truck collides with a 1500-lb car and causes a lot of dama)i4vc mu vu4n8bf:hh8 ge to the car. Since a lot of damage is donhmcbuh fv u)8i44:vn8e on the car

  An object of mass m sits on a flat table. Th4z ho mgs0k;apf6;v*ze Earth pulls on this object with force mg, o 6p;z0a v;smhk*zfg4 which we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceil0vc 0va6.udft- 8mpgv9i3azt ing by means of a string. The Earth pulls downward on the toy with its weight force o8vvz udvi9a t63g0pcm.-fa t0f 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 force. The b 5rskdmxi :,b6:n4 lmun)ra i8all hits the bat with an instantaneous force, who nim)uira6n48 b s r:k:ld,5mxse magnitude is

State Newton's three lawho* t1hhjy4s *s.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Eml ,fo3m 7s4xiarth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Earthi7 oxl fm3s,4m?

  An example of a force which acts at a distance islf kqe*hg/(; 3vt9s kd

  Who has a greater weight to mass ratio, a pers k,u*ct;dll:2tzvb 9 ton weighing 400 N or a person weighing zcll;vt du *t2t 9b:,k600 N?

  A stone is thrown straight up. At the top of its path, the net p i7x6yz r2mqerw-0d* force acting on it ri2 -dq7*zr6wxm e0ypis

  A 20-N weight and a 5.0-N weight ak+/ f;l d ke4rxzib;5mz o-si7re dropped simultaneously from the same height. Ignore air resistance. Compare their acceleratii r sdelkzfz5/o4 k x+;bm-i;7ons.

  A brick and a feather fall to the elmk +1snb4q h*arth at their respective terminal velocities. Which object experiences the greater force of ail*4 1hns km+bqr friction?

  An object of mass m is hanging by a string from jf k6t-/,ohe4qdy m)(khu j6dthe ceiling of an elevator. The elevator is moving up at constant speed. Wha)/4 d-uhekh jdq6(, f yjmot6kt is the tension in the string?

  An object of mass m is hanging by a string from the ceiling6.x ru r8(x+gm xx(s9vboho7t of an elevator. The elevator is movinghx . oxrbrmx7+o g 69t((u8svx upward, but slowing down. What is the tension in the string?

  The force that keepsep/ .p7-nj dg7hgi1 jegfx9m zw,d 5(h you from sliding on an icy sidewalk is

  It's more difficult to start moving z:0gmv gt/(jsa heavy carton from rest than it is to keep pushing it with constant velocity, beca0(g vz: mgjs/tuse

  A horizontal force accelerates a box from rest acroubht 1 lxjqd78.ao 7h7j;7zoyss a horizontal surface (friction is present) at a constant rateoa77ozxdqbj1 u77l ;h8j. yth. The experiment 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 an inclined ramp at cq8 gii;fzwivcv 4n;m,5e/*wfonstant velocity. Thus we can d miivev5q84 in*f z/wcw,;gf ;educe that

  A block of mass M slides down a frictionless plane inclined at an an uoy0n)3xl(hsgle q with the horizontal. The normal reacs(hun3o )0xy ltion force exerted by the plane on the block is

  A block of mass M slides down yruoxsz1ur*y*vqk *362yu h; a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the pla6yuh 1y**3vzr u*uksyqr ;o 2xne on the block is directed

  A block of mass M slides down a fric oi,6kavc ;t/8doj( shtionless plane inclined at an angle q with the horizontal. The gravitational forvd j/6o ;kct,i8so(ahce is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an inclined pl:1kui(jt nv us ze.6zhc. v8k-ane thatuck s tz.(vz81j.u-eikv :6hn makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied td5;d t-yr 0 0scp)pdcho the object, and it acceleratp-c d5t;0 )dhdy srpc0es at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 10evpc 3;u*2ncv00 kg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward forc*n e cpu2c3;vve on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 sepw y7uqd g;wl7)g2nf1v .,q,s wbj,d. What is tsp v7uq2g) 7njd.e f1w ,ywwd,g l,q;bhe net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquir eppe)q24 fep6es a speed of 50.0 m/s after te eeqfp246 )ppraveling
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 1(1z/ zz tarqy3tl e2y*0-kg mass from ree tz1qyzr/yt*z 2 3la(st,

  What is the mass of a person who weighs 110 lb?tbezb 6 0)gf/der4l9 tci,.xp2 vtp+g

  What is the mass of an object that weighs 250 N on) evk qc,m0f+w the surface of the Earth where the acceleratime)c q,wf k0v+on due to gravity is $9.80 \; m/s^2$?

  An object has a mass o*1jc+sffv;*fzsu20 lhm(m cr f 60 kg on the Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity+r f1 u2f*cl0 ;(smjfmv csz*h is only 1/6 of that on the Earth?

  Object A weighs 40 N on Eu+2 m:zzzyo) harth, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses ofy:2)z mozu+z h the objects.

  Sue and Sean are havingtd+m8dca l mylag11, + a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the +am alc18yd1m lg+, tdrope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F actsm( escg:s7 x)n on the stack, and itm x:s()7egnsc 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 m1f9/rq/lq e*c4usi:vpsqcgw 8 l s.7 stands on a scale in an elevator. What will the scale be reading when the elevator is accelerating downw9ir/8sgu:ql1* f mq . ss/pqw4e7vcclard at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person w 0sh: m(9p(tozqjiy 3is 60.0 kg and the elevator accelerates downward(:wmph3zo j9i y0st q( 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 person is 60.0s,-lyeh n p k47az tqxs:*10js kg and the elevator accelerates upward with an acceleration os7sj-*z4e h pl0q :x,1tysknaf $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg+e2*ro5f w hdga g27h ;o1dcgx mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the a51g;eocxgg2d*7h+ h fw2rodeast 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 a truck. It is heyzc(m*75uq5/u lzw il ld in place by metal brackets that can exert a maxl zym*l(zu7u5/qic w5 imum 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 nx2zksn 9 tv:ankj-qw:9 d-6h 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 thek 9k:6:v ajxnds29zw-t nn-hq minimum stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shoguc.45 a.u bu 2i1xs p9ydc(ydwn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleratio ub52 s1uigcdyp x.yc(49a du.n of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.4crgy ;fi.bm1n* 4x9et0 kg, what is the tension in the string? (Ignore friction and te;rt14 fibx*g 9ymc.n he mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor f(zaxc) ot+qm f n; isa3pbw29tif)10with a force of 100 2t0(btnf9xaf1s3 fi )aicqopz;w)m +N 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 floolo( 9l bjg4q1ckb.g4kh(l)h hr with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.0 kg, what is the normal forhb o4l14h)q9c g(jl (khgkb. lce on the box?

  A traffic light of weight 100 N is suk,yd-h 3 vma*g3npyu8pported by two ropes as shown in Fig. 4-2. What are the tensi3-kh,y*p3 dn avgmu 8yons in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of the;q az;yu hkb695 z.eaq traffic azqkb qz5.a;hu;6 ye9light?

  Two boxes of masses m and 2m are in contact with each othe+) :m8 /o+.oxsb) 2wp ozqrv9gj smtipr on a frictionless surface. (See Fig. 4-3.) What is the acceleration /2rqpjpz: sm mg9v)o io8xbs )+tw.o+of the more massive box?

  Two boxes of masses m and 2m are iax;)a u9n4cm8fs;au jn contact with each other on a frictionless surface. (See Fig. 4-3.) What is the nc f)s8an j;uaa94;m uxet force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If tahd+c(xbe6m4, whg/v3 rnf d.kvf a;+he forward force on the more massive box is F, what is the tensi ( vakh4emd agb ;/hv+d.xnr+3c,ff6won in the connecting rope?

  Two boxes of masses me9zbgl8h ,:ve and 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleratio:9ze,hl eg8bv n of the less massive box?

Two boxes are connected by a cord running over a p67rpc3nl40kndi jv36yb qqb. ulley as shown in Fig. 4-5. Box I of mas3b kcv 6qn q.yn47rpljibd 360s
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 r/foi5ai 8:j ddx ay3hf, /m7ebox and a desk are 0.40 and 0.30, respectivel 38h om,57 xi/ed:y ffdaa/irjy. 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 fr(3g/vt s y 4yfd(mi m8uqa2ff(ictions for plastic on wood are 0.50 and 0.4m(vf f/a3f2y d((qys8m i ugt40,
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 sur;5jhb fu*0*prk1of wgface in the +x direction. It slows and comes to a stopf po fukg5r;* h*1b0wj 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 suag0dlc 6ob g, 8.0az0g;ousdorface is pulled by a 5.0-N force. A 3.0-N friction forc6 gzcbdguag0 o 8;os.0a0,lode retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 *h7u; zgf91kdnolfs : 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. It slides 5 v,ny6w 2a3rptuk)n9w4uo f q)0 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and the34kaf )yvo92n, 6utuq rn wp)w ice?

  During the investigation of a traffic acci2fcm5 pvlk0, jdent, 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 conditio v0l,kpf5 jm2cns. 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 surfa4y fiqy6*lebp lp) p:pyv 503w 7i0gvtce between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the :v q wetylp* 3b yliv50yp f)7ig04pp6less 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. 4-6.) Thecz,; b3twsj1-v uy z(y 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, what is v,3yy(;t1cw bzzj-us the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is0idah1 g1dqf5 inclined at an anglea5 fhq10dd i1g of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle.lj1),yz0t fkfr5) x+d cqcwy 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 sh /t)+ecuhwt5v70,azp5d yb 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 pl,( bdaeh02 4r3cwqcmuane 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 m ppzk* g,*:v;cscr i9directly down an inclined plane, at a constant velocity of 6.0 m/s.cm :i;gkv p9*,scp*rz
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;r+;0 rp cg 9iph9esir2ac+f l slides 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 s-/q j1di1kurm lides 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 lb2ykb;4eg1y weighing 500 N along a rough surface. The cable attached to the log mabbl;y1 4eg2k ykes 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 rougjr)6.w,fk8j+ i/ganor n sstrhu ); v0h inclined plane tilted at an angle nrra wgouvj8) t60+i)/ shf.sjn r;, kof $33.5^{\circ}$ 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 incline is graduallymv2;nhi ee 4:x increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the 4nehi :;vx2m eobject and the plane?