Which of Newton's laws bi rhqe rw,0r0;est explains why motorists should buckle-up?

  When you sit on a chair, ;e; obx(xj-a m 1ryxvpj8:ct 9the resultant force on you is

  In the absence of an external for b*sji/zpp,06c,qx qtce, a moving object will

  When the rocket engines on the starship N( oyt/yl /by7d 9x vxj++yjnc,O-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starsh (xlyv7/yy+j ,9+nbdojt yx/ cip will

  A rocket moves through empty space in a straight line with constant speedz8 qp12ok sku0:.g paq. It is far from the gravitational effect of any star or planet.qs0:oqk21au 8. zppg k 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 soo*xp1g+-aa* n b o.yzw6 jg5iuddenly fall forward. You can ima w.o +o-yzga onx1j5g6pbi* *ply from this that the bus's

  You are standing in a moutc0d)f6 - , gxs*,i cq+.qrj,vsxhu vving bus, facing forward, and you suddenly fall forward as the bus comes to *,hx tx+s.),sjf c cvi0-u6drugqv,qan immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objecr+pn: :1g .bzz axumk u6- 7fv/wnfzyp*lt*1yt.

  The acceleration of an object is inverr -/bnp95wv8e5 onaus+s : khpsely proportional to

  A net force F accelerates a mass m with ans*vb:iw+ : +ywforw/ n acceleration a. If the same net force is applied to mass 2m, then the acceleb+w :s ywwovirf *n+:/ration will be

  A net force F acts on a mass m and produces an accel;s2v vdg*iiu0+z1 dfl eration a. What acceleration results if a ne i1+ *ig2;l sdz0dfvvut force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloo7o(ok j.cq z i8m48hh. q*ollbn will fly away. This is an i84 ih8o ojlm*h k.q.(l7zcbqollustration of

  Two cars collide head-on. f4 j2 7cwhbbp(At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equal to tp(4 cw7bjhbf2he 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, mtefu rls gpf,ft*4.i+p+n ; h:v .1oithe force which the object exerts on you will *niu1ptlo,;..f+egmf4tv:phr fis +

  Action-reaction forc;ljqn.(s iqr zwzb/y: -ul,f,;ki) cdes

  Action-reaction forces are*l3cz w7ybv fnfaz ;e5*ncf63

  A 20-ton truck collides with a 1500-lb car and causes a lot of dam uph d)1cg85zvf-sut ,age to the car. Since a lot of damage i)g5v8 s,u-ctdh pf 1uzs done on the car

  An object of mass m sits on a flat t0/hm x8d0sc nfable. The Earth pulls on this object with force mg, which we will call the action force. s0xmn/hf 0cd8 What is the reaction force?

  A child's toy is suspended from th5+fj1wjsxqfan53 s6ze ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction1wfx5z65nsjaj3 s fq+ force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous f-sx.u. bh,j rc33z- sfv(fmz worce. The ball hits the bat with an instantaneous force, w-s-x 3 (.3 c,jfzmusfbhzvrw.hose magnitude is

State Newton's three l9 mf dnrc8)kcn- cbl:.aws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Whichqrtuxwr6 ka8 d5n,q ur.o3 e(/ of the frqa 8dutq,/ko3we6run 5( . xrollowing is true about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distanc.ama ,+jeppdi 0rc,z5 5 mgpq2e is

  Who has a greater weighmff.) 9z nw2pnrj.*p qt to mass ratio, a person weighing 400 N or a person weighm9rzf *. jpqw2nfn.)p ing 600 N?

  A stone is thrown straight up. Ata2)ya 2. 2qb a;vajzos the top of its path, the net force acting on a)aoaz2q j v2a.b2sy;it is

  A 20-N weight and a 5.0-N weigh5,)ydlyx1vm u t are dropped simultaneously from the same height. Ignore air resistance. Comv) 1xyy ,ul5mdpare their accelerations.

  A brick and a feather fall to the earth at their x)(rcmnuy3u 0 respective terminal velocities. Which object experiencerxu)(yu cmn30 s the greater force of air friction?

  An object of mass m is hanging by a string nib h( )w*cc*kfrom the ceiling of an elevator. The elevator is moving up at constant speed. What is the tension i) cbkhni(w *c*n the string?

  An object of mass m is hanging by a string fropk17hmm6mmo,hd ei 0z,. m m9h(h uvgj8zz 00km the ceiling of an elevator. The elevator is moving upward, but slowing d h mhh0 10.om8v0mzz im9hgpm7e,zmk,jd( ku6own. What is the tension in the string?

  The force that keeps you from sliding on an icy sidewalk v1*ckp)ztsd a 7;0h- ow bhz.xis

  It's more difficult to start moving a heavy ca 8i u * d*6 vgg(u-q,qz3+us;euetvbwyrton from rest than it is to keep pushing it with constant velocity,;esuwy *gvzu *u(tqvdg uei6- 3q+ b,8 because

  A horizontal force accelerates a box from rest acros(-:kk ,r +souxfg k4vgs a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exceptioo:4,fu gksk x+rv (-gkn that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus wexpwdr;7 f- xplnc:a-21 jgd-y 7,fotu can dedy doj-ppt f-2 wgx xrn7,f1c;u7d-a:luce that

  A block of mass M sli ewb7 9n0qe4lynr/g;jl;7y ey9c lb/ides down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the blockcyl jbr;/0yq;w47n/ gni97eyl l9bee is

  A block of mass M slides down a frictiongnom49 os;o:e(b p-qw less plane inclined at an angle q with the horizontal. The normal reaction force exerted9 o:nqwe4g( sp-oob; m by the plane on the block is directed

  A block of mass M sl;s7uwrh)g :tr vgwcx*k(9j5sides down a frictionless plane inclined at an angle q with the horizontal. The gravitational for 9rtg ;w57h*u:kvsj)cr s (gxwce is directed

  Two toy cars (16 kg and 2.0 kg)9 ;dvi tqfg(05807hh e zbsrbt are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a state(t ezghbtvi8h0bsr 597qd;f 0 ment which best describes their acceleration after being released.

  An object sits on a frictionless p fvu900m)fc csurface. A 16-N force is applied to the object, um0)cvf0 pfc9 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 frzvb qg4xh.k :5 ot+ ,gami(x-com rest to 27 m/s in 7.0 s. What is the average forward force on( g5axo4-cz,h: qixtg+m bvk. the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is ldw oogr89y 7rm 3y5*tth3 orm* y7 glt8owyrd95e net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acqu wgd jw ob)/j 7kf6:s9g4b8rlgires a speed of 50.0 m/s after traveling 9:k)ws w od7jb/ grfbl6g4gj8
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 tmvybpo jxs)3 4(6q,fsame force that you push a 10-kg mass from rest, )6(qb4, vfsmj pox3yt

  What is the mass of a person who wex9x mircwx+0i0rz :qze e8/2:xvbnf+ighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Ea5*q29e(,k t vr4 tcojnn4g uqhrth where the acceleratje,kqg4v9 o(trn* 2c tq5hn4uion due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of t,:306 hmlbto sc5hah ehe object on thec5omhtshh ,6bl:03 a e surface of the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and objectpb5g-djx,w,6 / er xcs B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of the o pj/,5s-rx wc,6x dgbebjects.

  Sue and Sean are having a tug-of-war by pu ugv1+ e2dv8-4anpb vslling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's vd18nvv usaeg 4+2b-pforce 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 acts lzccw 68;auaf2 .qr2d5: /jj+zw *sv5rq xorjon the stack, and ijjzc x+/2lcuq;ao a s2:r58j5*f. w rdz6wrq vt 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 scjnolpu8p2u /8ud. b2 gml16 irale in an elevator. What will the scale be reading when the elevator is accelerating dowpju21p /guu.oi8r8dm2l l6nbnward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the persoeugf0du0,4vlk9l e m6cnh8c3n is 60.0 kg and the elen30um08 elvh6gfkeu9l4cc d ,vator 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 an elevator. If tht(z,) n-k0 oqztj.evhe mass of the person is 60.0 kg and the elevator accelerates upward with an a-j)t ,ztez o 0h.(vqkncceleration 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 has5fg-:vtvvn 6gofi 1w*9wpbpz bc/du1(u8 4hb a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the acceletp 6:u vo bb4*vbg8 1puzh/( - wdv1fgi5n9wcfration of the mass?

  An object of mass 6000 kg rest/uwl;dfi3dd 1zk1vx6 s on the flatbed 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 the minimum stoppud zk ddf 1x/l3wv16;iing distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the fwb3zqfrxhu 4yr (80: elatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal forcuz4b fr8e :qxyh(0 3rwe 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 machin,- w6ca; plyyde shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the ,;yldyc p-wa6acceleration 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 = 0.40 kg, whb qxpwckaz,gxt8e1a h- h)+r8 20nx,kat is the tension in the string? (Ignore friction and the mas-xbz,0ktw8xhk r +2a 1p,n x)cqh8ega s of the pulley.)

  A student pulls a box of books on a sm0s5q xz3)ee9 pff7au hooth horizontal floor with a force of 100 N in a dirp3z7sh0xe fe u)9aqf5 ection 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 ag dlzgzd z9cg47*d4u -cw;:vk7+ izpw u4p+ wu force of 100 N in a direction of 37.0e above the horizontal. -z*;d4 74i+gduw g zd9lpz4c7: ucgk pw+vwuz 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 weight 100 N is supported by two ropes as shown in Fig. 4-2.gz:+qdonx;t;yyo1 q4 87fgbp What are the tensions in tqpo y:n gqxdzb;of;7t+1g8 y4he ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, 6dk4c0vb0lnk(6z k ucwhat is the mass of the traffic lightv( nk4uk 6kdbclc0z0 6?

  Two boxes of masses m and 2m are in contact with each other on a +qyb.n-ft*jhh, ql l 4u+7jlg frictionless surface. (See Fig. 4-3.) What is the ac.+jl,l ntf*u+lbh-7q4 j gqyhceleration of the more massive box?

  Two boxes of masses m and 2m are in cont l icdvt8d *bca daf2b.v/3ry47mx 2m8act with each other on a frictionless surface. (See d dvcai22y74l 8r bdmv8a/3.xfmc*tbFig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are conne a42oc9:wh zvb99 srqpcted by a rope. (See Fig. 4-4.) If the forward force on the more massive box isswqbcra42 :vh9 p99o z F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connect;c0 slzxu fl 492k6qwted by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the acceleratiowufs;zlxkl2q 4t 906c n of the less massive box?

Two boxes are connected by a cord runningtx )zt:q5 clbt6qu/:o over a pulley as shown in Fig. 4-5. Box I of mass/b56 t cl)zutq::t qxo
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 btid*p 0z7fd6 qetween 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 hqfidz*t7p6d0 orizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic ocm,f zw9r )tf5 lks,3in wood are 0.50 and 0.f9r5f)tw3c,z li ,m ks40,
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 slow0rbr .aoyiybr w7 k/7,s and comes to aai.7o,b rbwyrr 7y0 /k stop 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 0t45gkb 6/v wmy k5viva horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration kiyv/0b t45mkwvv 56g of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, frnsi 6te 3m1q7p;o ,lnvom 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 r40br.9wgps2x.yhyfl6 w0 g op2v.tu 50 m on the ice before it stops. What is wlx. 2 sf4wy2. op0rr .9h ggv6bpyu0tthe coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, poqvqi7r 9:sd p:ym-y0 zlice find skid marks 90.0 m long.7qpi:myv zq :d0sr y9- 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 were applied.

  Two boxes of masses m and 3m e )lmu65nv0qzc5a7poare stacked. (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, what is the static friction force on the less massive boxcm 6oez5ua5)nq7 0plv?

  Two boxes of masses m and 3m are stacked. s cor7t7zc+9a(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, what is the coefficient of static friction tz oc779scar+ between the boxes?

  An object is on a frictionless inclined plane. The p ql1ln(ni/vl./m3i2f 6/n hqvsu xz)olane is inclined at an angle ovui 6hvlz/n/nl/qsn3ml1xi () oq2 f .f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a f 5.ph l,m,7jysubki-nlat hill 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 smooth inclined plane with yswz 3t( 02rcran 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 b ac5ko5;n14 4zaxwop:0 md 5 mzx+aho4gm7o tan 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 lg+qh.4 pv* dudu)ac-velocity of 6.0 m/ qplv*4du hu.-g) ad+cs.
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 roughxafzjh*p4wfl2a 1.;r $37^{\circ}$ 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 rhvwe3k- c m-o2 wr0d2dough $37^{\circ}$ 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 suql(b23.znr bi mhw9o/uc(d4srface. The cable attached to the l9c2wrlbniu s3b m ((o.4dz qh/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 i-u4i 8vng.begy+633/ j0vpahykw f p6 md-ehynclined plane tilted at an angle o-m6 4g evpia3yg+dh0/ykh.jy3f np6wb8e-uvf $33.5^{\circ}$ 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.*.y 69b,dxjidh 2 p.iclkcw2d The angle 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 between thdy, j dwc2.lpc*xib96 i2dkh .e object and the plane?