Which of Newton's laws best explains 134qyx5m k+ uk p2r ra1ue1lzaxx*(tywhy motorists should buckle-up?

  When you sit on a chair, the resultant fojvf :hc88,:s9x tbvt rrce on you is

  In the absence of an ns :* 3t;mavud7iue9eexternal force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN ,.grwr4 (ez njare suddenly turned off, while traveling i z.w,n4(egjrr n empty space, the starship will

  A rocket moves through empty space in a straight line with constavi0dt1za+u 6d nt speed. It is far from the gravitational effect of any star or planet. Under these codta6di v1u z0+nditions, the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing d5)vbc.rcm4el (0 yeg forward, and you suddenly fall forward. You canbrdm4) e0v.eclc (5yg imply from this that the bus's

  You are standing in a moving bus, facing faa d e6*/utgo,orward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused you to uaa6td* g/o,efall forward?

  A constant net force actsb9o +b9)fsdz v on an object. Describe the motion of the object.

  The acceleration of an object is ind y. iusk-1 gb;xxi:r9versely proportional to

  A net force F accelerates a mass m with an accelerat/8hje 5-qrcg+3mt f-1w ajdr vion a. If the same net force is applied to mass 2m, then the acceleration wil+v mcr wt-h rq83e1f5/g j-adjl be

  A net force F acts on a mass m and prot:wkd+qai qhl -jq,)9duces an acceleration a. What acceleration results if a neatk)qj, w 9ql-:qd+hit force 2F acts on mass 4m?

  If you blow up a balloon, and th4*xo(dnmvv3 sen release it, the balloon will fly away. This is an illustra*(smv3dx 4von tion of

  Two cars collide head-on. At every moment during the collisiowt l. rm1 wcod5 t1vswu01/3afn, 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 fir uts3rtl1aw1 wd./wvc0 of 51mst. This is an example of

  If you exert a force F on an object, the force which the object exerts on you m jmje06y3h1v 6 6jwuiwiejm6jimu63 yj16 0hwvll

  Action-reaction force )khvg/7/gfrg2a(pl (8xm s6rlv+x nns

  Action-reaction forces urt0mcv8b tr03s5q8vw zc j/- are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage lnd7 1;cu( payk sa1 5v)s/oetto the car. Since a lot of damage is d oc15s 1/ ;a) ds(alekvutyn7pone on the car

  An object of mass m sits on lphb tu4vsv ,3 zmsqa31 cr.0,a flat table. The Earth pulls on this object with forc.l,mhpzvq14 bc,vsr0tus33a e mg, which we will call the action force. What is the reaction force?

  A child's toy is suspend 6c2m hk88 nat lv37lxbsyu64cq wn87hed from the 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 "react7nb h h6 8k4 xsvm 8cqwyl7c8tn26l3uaion force"?

  Your bat hits the ball pitched to you with aoi y/lok :5 oq* dwwvmmr)5q /uq7-r.q 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose magnitude isw-okqoq 5m.:vyol/ rq qd5/mr*7w)u i

State Newton's three law ve* 2gfb .1ak:g)z kh4d(btpbs.

  Mass and weight

  The acceleration due to gravity is lower on the Moon tj;j/z,pxy xx 3ado(7 ru;tce(han on Earth. Which of the following is true about txyxxrejup(c/ a; 37dt z,oj( ;he mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts atf5 ( sjt:k++9fkuse lw2nw7am a distance is

  Who has a greater weight to mass rx-.gyd9mh ev 2atio, a person weighing 400 N or a person weighing vxy9dmg 2-he.600 N?

  A stone is thrown straight up. At the top of its path, the net force acl *k.3*xx1wch f.ac0v8vw z miting on it is3c.lcxwhwv **kvix0 mf1. 8 az

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same hum h v)*m/cpo+eight. Ignoreuv)co mh*+ mp/ air resistance. Compare their accelerations.

  A brick and a feather fall to the ea3m095wn rmlo 6 dwu*hgrth at their respective terminal velocities. Which object experiences the greater 3rdg*m5w6m0 ul9wn oh force of air friction?

  An object of mass m is han w7ccqr1 h. 2h5rj qhals79ql6ging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What .1w j67r7a2qqhrhlls 9c5qhc is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevatxw+d:8 kax 57y 8googfor. The elevator is movg a xxoyog88+d5wf :k7ing upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidewae bzvd7imh,qh 9u) m/0lk is

  It's more difficult to start moving a heavy carton from rest than io 7pihlh)eo0,f xpd8*nvm he +o9/ ua0t is to keep pushing it with const e x0no uohppm v89dih07+, h/efal*)oant velocity, because

  A horizontal force accelerates a box from rest across a horizonty9po7iul) m4i al surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception tpu9)yo4i 7ilm hat the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down pc+e j22uqs qo*2c5/s ah8+no3rog cn an inclined ramp at constant velocity. Thus we can deduce t/qu spqoc2o22caojen+5 3sg cr+ 8n*hhat

  A block of mass M slides dowm71 jg+n gcfin ;t/;j(kjt; qan a frictionless plane inclined at an angle q with the horizontal. The normal7;iq annjf cmkjt;gj+gt ( ;/1 reaction force exerted by the plane on the block is

  A block of mass M slides down a fric scxe (y7j2c,m o/j:nu esyg4*tionless plane inclined at an angle q with thoe /sy*c:uj(2 sm e,47ycjgnxe horizontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a fri- 4um b(pme4ci1f):dtm qr3gotb0sfq4qd )- yctionless plane inclined at an angle q with the horizontal. The p :ud0mo)q1te4fbd )cq-my(gfrb -q3smt 44 igravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are releasenvm3ky;lq9.g t*h ivl ,y6c( md simultaneously on an inclined plane that makes an anglm, y6vi . vy3g(;*m t9cnqlklhe 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 to the objec+h;rpx8 6imr b e*mi6rt, and it a+r;ipir m6ehbr8 6x*mccelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 10+zq:,z m3 fiuqos7ido e+c0 (z00 kg can accelerate from rest to 27 m/s in 7.0 s. What is the averageqqd3fs+moo ziez :z0, (c+u7i forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. Whao;s8syplyzl5 u 2p-e bzn3h-(t is the net l-zbo- hsup p;5e3lyn8szy2(force acting on the body?

  An antitank weapon fires a 3.00-kb: af)i-z *spfg rocket which acquires a speed of 50.0 m/s aftei pza*fs -:)bfr 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 that you push a 10-kg 9btvg:c8 6h7eoq- jv nmass from rest,o-b :q7ghctv8j 9ev 6n

  What is the mass of uw m,z- dzrvwflkwkbpqz-r:eh 47z.8 ,,xe/8a person who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Earth vvozwh4fi2 kp)+c j(:where the acceleration due to gravikh :)p(ofw2vv j4icz+ty is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on they :d9rtkm(n4zar/ -y 66xugv n Earth. What is the mass of the object on the surface of the Moon d/nu46agrm:v( yx-6rt zk 9 ynwhere the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weigh :,6m f+hfxttxs 40 N on the Moon. The Moon's gravity is one sixth of Earth's.f,x txf+ 6htm: Compare the masses of the objects.

  Sue and Sean are having a tui*f 6:53vywzj smlb.28zxc omg-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sf 5 iy szz mc2v3*wjml.:o8b6xean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books resmi( z3 nk j a)u7f+:kd4vetgf+ts on a level frictionless surface. A force F acts on the stace+i3fdk7 utg k)j4+ zfmna( v:k, and it 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 in an e-9w rryt g8vn3(scat1levator. What will the scale be retcw ryn- 1tv8s g9a(r3ading when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person a hs ek,0;ru(fis 60.0 kg and the elevator accelerates downward with an accer0 k, sahfe(;uleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an e7cm ypg.o.dkf- 80qjzlevator. If the mass of the person is 60.0 kg and the elevatokgy7p8jzqd0- ..cmof r 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:uqw i31ixgk v i2 z5l7.xabf( has a magnitude of 8.0 N and is directed due north. i7 v325(lxxwb uf.:1igzkaiq The second force toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kg restk ,mvn bkj*g:x)oo ;1ps 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 st :kpj,m*)oxgv1n; kboopping 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 pl3 iwazij eh 79a8)0ikdace 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 ldia j 8)a0wi73zkeih9oad is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what b3lo : xqdud3i 8ko:qzeb; :6zis the magnitude of the acce:3 ubexkq zl:bd:; zdi38qo6oleration 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, whbzvs4xx.(iz; 0 cfh*d at is the tension in the string? (Ignore friction andbxvzxs.(4d0f ;hzci* the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with6fzj7 48:un(txtq roa a force of 100 N in a direx nqoja6 u:t7tr f(z48ction 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 i o9)*jj9zpwxww;- k qof 100 N in a direction of 37.0e above the horizontal. If the mass of the box and thew*9j9i;xwkzow )q -pj books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N39kmpv 6v7z 2mvpo kx- is supported by two ropes as shown in Fig. 4-2. What are the tensions-p2m7pxkm z v 9k3ov6v in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass on1;0kv vq3eyp f the traffic ligen3qvp ky01v ;ht?

  Two boxes of masses m and 2m are in contact with each other on a frictionlejxb/e3y ; 0rkeguf/ 2un-l 81pqjvnef3wxd *0 ss surface. (See Fig. 4-3.) What is the acceleration of the more mk3qnee 0gu;n/ 18/xu3jd fv2p0-jx *ef wy rlbassive box?

  Two boxes of masses m and 2m are in contact witvgmu: 4,p9wnwqkc+c (;xby0ah each other on a frictionless surface. (See Fig. 4-3.) What ic,4pk ynu:9( m+qwag;w xbcv 0s the net force on the more massive box?

  Two boxes of masses m and 2m adxt5 yaquy2o4 bzxwn64y625ire connected by a rope. (See Fig. 4-4.) If the forward fordn o wq xi56ya2xty6b54yu2z4ce 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 s6wy3 nh.z;dh Fig. 4-4.) If the forward force on the more massive b;6ywh s3hdz.n ox is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running 5:,(+x ora-lxsp bqsrover a pulley as shown in Fig. 4-5. Box I of mas(bxrop x,:aqs +r-ls 5s
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 betwe1,g- r vad4q:*g l1 1qnceyzpsen a 3.0-kg box and a desk are 0.40 cs *e1,4n l11qgv :rqgza-ypdand 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 statpkr 77;2sj kvuu w,nts5ob a72ic and kinetic frictions for plastic on wood are 0.50 and 0ru7 7,ov7wnka;b2jup ss tk 25.40,
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 o3c:9uva, y fnv),h pqslows and comes to a stop with a constant acceleration oof),3y9:uqah nvvp , cf -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surffkp(1 ;k koi6 2;xmxgoace is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceler2f k1mipokk g;x6o( x;ation of the object?

  A horizontal force of 5.0 N accelerates9uzmtm, kos8 / 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 /( cttvdm t3;ypuck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is th tmvd( 3tcty;/e coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find skid marks f1opa 29 b tpx8qbjq0790.0 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0qxp972pft1q0j b o8ab .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 suy6xoyal80 o)j m0 k xivd1 +g)bt*e6yirface 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 th0+a x)i01gojbl 8yvex)6o*td kyy6m i e more massive box, what is the static friction force on the less massive box?

  Two boxes of masses m ay8+z x9p3u q o1bact0ynd 3m are 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 coefficient of static friction between the b 03 tuo8 bcya1yx+9qzpoxes?

  An object is on a frictionless inclined plane. The plane is inclined at/4bibm 1rd9 ;luyje-r an angle ofd/- l ru;jmy9b er4b1i $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a(o roskzpevy2t3mwel,n(w d6i:o 5: 3 flat 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 an an-- arlchd0f0dj de7+tgle 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 angle kb4 j 53znisv)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, azw z.lr 7c+m9jt a constant velocity of 7j9wcz+ .lmrz6.0 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 slides dow (w:sfa(4wrga9 tf7sm /v y9zqn 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 sl fa jo0*h ca+m6 j x;vrn0a;tp,8y.vbwides 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 surbq)hdi*sr*( eface. The cable attached to the lo q*rsh( )eb*idg 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 restoavzjv60j c40w,a1di on a rough inclined plane tilted at an angle ofdajjoaw00v,4z6i v c 1 $33.5^{\circ}$ 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 incli n)wknod7-b) nned plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this o) nd) nn-bkw7occurs is q. What is the coefficient of static friction between the object and the plane?