Which of Newton's laws best explains why motorists should ls+s)fb p/hzuel: ://onp+h kbuckle-up?

  When you sit on a chair, the ro r5 zo xures1nj(*1zz3i7 y-uydbm6 0esultant force on you is

  In the absence of an external force, a moving object wiwi.6n0yzdz5sh2 4 bbjll

  When the rocket engines on the starship NO-PAIN-NO-GAIN are s rng2 j2.v8e(-5ejr qodd1uhnuddenly turned off, while traveling in empty 5ongj-d8ej 2(r.d2nh req u1v space, the starship will

  A rocket moves through empty space in a straight line with constg) z3iu+w:kw mmof+yg3l)9z y h2cr,bant speed. It is far from theky2)hio9w3 wl3z)+ u+frmzb,cgmg: y 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 suddenlyq x4 72yuha th6ng*c-s fall forward. You can i*u-x74snty2hgh q6a cmply from this that the bus's

  You are standing in a movltb df5s0) orz4.3i,w u+ngrcing bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. What s co+r3u ,nd)5flr gz.4 wib0tforce caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the o6(vb. dd w 1eob3rs1ssbject.

  The acceleration of an objectd:lk9 a3ssy5 g is inversely proportional to

  A net force F accelerates cpr2yj(bl07 nd .b, cra mass m with an acceleration a. If the same net force is ap2 y(r jcd b,bpr.nl7c0plied to mass 2m, then the acceleration will be

  A net force F acts on a masskmjxt s+x8/o 6 m and produces an acceleration a. What acceleration reo8x6/tx km+j ssults if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly awa 1zq7 mq2e y;s qe0jsbz7r0sc0y. This is an ill1 s0erq jc7sq00s2;7 bzq zemyustration of

  Two cars collide head-on. At every moment during the collimq*al i4 bgvb/dlhc ze1c:o+bc .;96 tsion, the magnitude of the force the first car exerts on the second is exactly equal to the ma6bdbc .4/*mgzeo+cb9cll: ai1 vtq;hgnitude of the force the second car exerts on the first. This is an example of

  If you exert a force F on an objec;id8xht+d . yjt, the force which the object exerts on you wilydtj ; 8xh+i.dl

  Action-reaction forceops 88h)ja5 u2hi. ink4xg/s cs

  Action-reaction forces ar v e ez vm1la( qn-qqm-zq6:ufe2 pb;k(y28kr6e

  A 20-ton truck collides with a 1500-lb car and causes a lot of dfx czaxv(jr:xxlh , y6k, 2 stkscr9+j.93dp5amage to the car. Since ay5dkx93ssx:txxcl6(pra rfj. +,hv 9j,c z2k lot of damage is done on the car

  An object of mass m sits on a7z886nc.- e5dyvy udee: tabt flat table. The Earth pulls on this object with force mg, which we will call the action force. What is the reaction ford.ne t y 6y8dcee5 ta:-ub7v8zce?

  A child's toy is suspended from the ceiling by means of a string. Theoee( 6him(o+ l Earth pulls downward((hoelmo + ei6 on the toy with 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-N2k3 )rx,zcswi instantaneous force. The ball hits the bat with an instantaneous force, whose magnitude wk2s,3zixcr ) is

State Newton's threes) j r .i97vsiu-iaeaf+ x2gu4 laws.

  Mass and weight

  The acceleration due to gravity is lower on the Moo57jo9p(s/ (sgkj1 nrx s/ aqnxfdn9,trx f;j2n than on Earth. Which of the following is trorx n d9/xq9gfas7xs kt 1nfsp (jj 2;r,5n/j(ue about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force w q 59iq3j(vhsxhich acts at a distance is

  Who has a greater weight to mass ratio, a pg5csuo xo -d;d5,wv nb wm3p+*erson weighing 400 N or a person weighing 600 Ncsonov5ux-*g5dd 3w ;pw+b,m ?

  A stone is thrown straight up. At the top guz 8qo hlw en7:b0m.h2,er7sof its path, the net force acting on qu.hzbml27eges :87w nrh,o0it is

  A 20-N weight and a 5.0-N weight are dropped simultaneous.ob,*8l gz b6)hxfqatqvd2r) ly from the same height. Igg,x.) b86har *qd )2tqlvozfb nore air resistance. Compare their accelerations.

  A brick and a feather f55pn,gwvdqez* 1 y s4 hccq10tall to the earth at their respective terminal velocities. Which object experiences the greater force oz d*t 545wv,csgepcqhn1 01 qyf air friction?

  An object of mass m is hanging by a string from the ceiling ofhe - ::zd9b3kavfdvl+xy83p g an elevator. The elevator is moving up at constant speed. What is the tension in thy9pf8l:- eh+ a3d3dxz:gvv k be string?

  An object of mass m is hanging b5 hz0x0gzxkg(z9xdt )+prs8 k y a string from the ceiling of an elevator. The elevator ikh+zzkxgrz 0g)dp x05(s8x t9s moving upward, but slowing down. What is the tension in the string?

  The force that keeps you froz e klc:qh)e m,5fb.e.m sliding on an icy sidewalk is

  It's more difficult to px74rlj 5i7z qstart moving a heavy carton from rest than it is to keep pushing it with constant velocity,qp lrz57 j4ix7 because

  A horizontal force accelerates a bo7gm75rppftt;,lq r; bx from 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 ;pm,5r 7t;g bpl7ftrq box's acceleration?

  A packing crate slides down an i h)w3th e4k/yib76rhb nclined ramp at constant velocity. Thus we can dih4 6 k3b by)e7htrh/weduce that

  A block of mass M slides down a frictionless plane inclined at an1p1atk;2vmn:r g*)ze dcw ho( angle q with the horizontal. The normal reaction force exerted by the plan:;hwvoa1 dz1gmc k*nrt2e(p) e on the block is

  A block of mass M slides down a frictiony2 f34 zenie5xless plane inclined at an angle q with the horizontal. The normal reaction force exerted5 z32f 4ieeynx by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle.o:ui .yv va0xdc *lv/ q with thud vyxa.lv/0 .vc:o* ie horizontal. The gravitational force is directed

  Two toy cars (16 kg and0rzer3q/r) b 8udtbb2 2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement w/d ub3qzrt8 ) 2rrbbe0hich best describes their acceleration after being released.

  An object sits on a q-ki7+xfg 5lrm-qd l.vj:)x bfrictionless surface. A 16-N force is applied to the object, and it accelerates adfxi7rx gjv :5b)q- +.l klq-mt $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in 7.9h5p6dbae;kf4;c:3 c k kcrlo0 s. What is e cf;4bkadk;9cho kpl3 6r5c: the average forward force on the car?

  Starting from rest, a 4.0-kg body reaches0r nmlusiw(zy;6 57yd;8cv yw a speed of 8.0 m/s in 2.0 s. What is the net58u zns l6y c;w7wy;ym(0 irdv force acting on the body?

  An antitank weapon fires a 3.00-kf/zqeq cm*6p3g rocket which acquires a speed of 50.0 m/s aftzp/mf eq6cq *3er 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 cj ute.dn(hj(h 8 6i*gmass with the same force that you push a 10-kg mass from rest(henh(*j gjt8. i 6duc,

  What is the mass of a pm3vo: ej3ox.kerson who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surxx.u atcp17hh -zf mpzw6puq:9 n734qface of the Earth where the acceleration due to h u3p. up cq7:ptzh9zn fq1-x76 4xamwgravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the ve9l ybnw;.t(object on the surface of the Moon where the acceleration d 9ty(nw e.;blvue to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the dg3;4/ am5 vs88 ws+zfhkxf n xwyh;8zMoon. The Moon's gravity is one 8sv5k+ m fzhy4gsxz8hfd;/ 3xw; anw8sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends o 4vj8gh8ajh r1f a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward41grv 88hahj j Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surf8g,ki*w g((x df*r-yuyor9 ws7 glt .face. A force F acts on the stack, and i. sigx( 9dr,-* y(y7rftw*of8 gwuklgt 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 iafz hr4* fbtchlu*3 0f4fs*jp,h 2u 2kn an elevator. What will the scale be reading when the elevator is accelerating downward at0aj2 uucfrhs,k2f4z4*ph*fhbf 3 l *t $4.00 \; m/s^2$?

  A person on a scale rides in an elevatoshlb(wmt jx -+u x0s2/r. If the mass of the person is 60.0 kg and the elevator accelerates downward with an acceleratlx-m/ b +js 2xtuw0(hsion of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevator. If,3v 8 1c87 pgjuuevvybtpif;; the mass of the person is 60.0 kg and the elevator accelerates upward with an acu;g e y,vf8p7 vivu813t;cjbpceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg mass. One forcela:j)g:vufo)u1p btpe 9 m:r 9 has 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 thet:eur lpf1 m:pvj)go )au:9b9 acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a 3r7gm.jiwj: hy(wh 3ptruck. 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 is w3w p3ihgjjh( .r:7y mnot to slide forward into the cab?

  An object of mass 6000 kg rests on the fl le1 l;c z)7n/icu.xyuatbed of a truck. It is held in place by metal brackets that can exert a maximum horizi/ nx)cu1y.l;elzuc 7 ontal 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 cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40ub+w;/ 9vl tae kg, what is the magnitude of the acceleratiwvabutl e;/9+on of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, s moe,mgg1qz4d85, tdif M = 0.60 kg and m = 0.40 kg, what is the teng4 e8osd, 1dmz5,tg mqsion in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor,oj9ha y t5n/h with a force of 100 hjah5 n, to/y9N 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 w jtk )2g8bce8iith a force of 100 N in a direction of 37.0e above the horizontal. If the mass of th )tcgebji8 8k2e box and the books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supportedxb 6* asx3w0zq by two ropes as shown in Fig. 4-2. What arex*as w q360zbx the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, whatxag: f1+0 (nz) .mse ycmh-) je3plaqh: 3lvng is the mass of the traffic gen)p m:zgm s v+10haq:(c) yn -3j3lxhle .aflight?

  Two boxes of masses r2)mqn m.u/ f4m fv.pnm and 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the accelerationf/)2.r p mfnm uq.mn4v of the more massive box?

  Two boxes of masses m and 2m aregk pq:4lyz kcv 6n.:7i in contact with each other on a frictionless surface. (See Fig.ikkl vc47n.ygz 6::p q 4-3.) 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.) Iflh bg1w58/yczw n2xaqc 6 0+ax the forwardcwnclxa+ xb 5w6a28h1 z/gqy0 force on 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 rope. (See Fig. 4-4.) If thej2n myq:39cb77n ig6eegcl yh7tu6 x) forward force on the more massive box is F, what is the acceleration of th2y:9mq6c6exnil3 b7hyujtc 7n g 7 e)ge less massive box?

Two boxes are connected by a cortr a/pm3;1q3r2zo ebjd running over a pulley as shown in Fig. 4-5. Box I of maszqar 2 1 3jore;p3mt/bs
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 betwee6 -kb6f;pg lren 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 horizontal force i bl-6e6pg;krf s applied to the box?

  The coefficients of static av z./a6wvkpq0nd kinetic frictions for plastic on wood are 0.50 and 0.40,/wqa6vvpzk. 0
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 a9eo3 a(0ipxk and comes to a0x i9eaka3p(o 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 a horiz3vh m4 qp,xtqhm +g1s7ontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the,hs v41q3ht7mq m+pxg motion. What is the acceleration of the object?

  A horizontal force of 5.0 N w uu b edo ,xk+a9x9yo2;n16moaccelerates 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 anv 9,d0m nr.sxa initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coeffd0x rv9,as nm.icient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police finbpb89106slk 9qkk mxl d 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 conditions. Estimate the speqbkl6lk8 9b 19xkmp0sed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface b fwv5/4zxe1o:e . qpujetween the mor4 /efxev5qz:j o.up1 we 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 box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) T/droii lf4+hnu4y) -x1a 5k8cfoz0ha he surface between the more massive box and the horizod40 a8noz4h 5l -fia/x+ ) ok1rhuyicfntal 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 between the boxes?

  An object is on a frictionless inclined plane. The plane is inclineey9 y,v;viqkh :qmg:9.jv *mmd at an angle9 qvk;jhm9qv,v.g m:m:iy*ye 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 w .31z:+rjyqapw2t lsof $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclined plaum* a)wt f(1q-o2jt gwne 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 fdbp (ke9 e)g6tilted 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 velocityci2(67 o :yo-b xopwiwxs1j1i of 6.0 m/s1:jix2 bs6o- oiw 7wopi(x c1y.
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 downdo;ga.myjkm 3 j3y 13u 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 down a roug8jplxv b60 p6: symbm0blr2 y4h $37^{\circ}$ 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 Nzwk00 jo-29u cyc z0ac along a rough surface. The cable attached tz0 9u yczc20aj-o0 wcko the 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 inclina zu/m2 )yf8zcbh emz uk901p*ed plane tilted at an angle oua)8zez91fh y0 mcpk/u2*bzm f $33.5^{\circ}$ 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 gradually inc jh 5zn8ce*hcjj*8 i4hreased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the *j 485ij*c8hezhnjch object and the plane?