Which of Newton's laws bs+:l;-qvjv m 2,pcva u.*gkab est explains why motorists should buckle-up?

  When you sit on a chair, thektwci 16)ka u8d f.c.m resultant force on you is

  In the absence of an external forcn2c.doy sycqj6 ()4lze, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are sud:arrt/lchnwz;tldrr 7t,7(x:1qcf x 8 oc3- idenly turned off, while traveling in e7 rc-r3ta l xc1l, hi;xw c:dqt7zr8fnr(/ :tompty space, the starship will

  A rocket moves through empty space in a straight line with constant spein+h1j dyxhlg+1uavh 4 :ce.+ed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be ap+j+hv1i .hxe g +hu 1nly:cd4aplied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, ans+99pfkf h3w5w2c : tg(qh-cxsfvr) nd you suddenly fall forward. You caxkns95cp(2 fv hqfc:)r9t w3 -f +whsgn imply from this that the bus's

  You are standing in a moving bus, facing o5-vj yk+;7w 0v5uwdxy6uurgforward, and you suddenly fall forward as the bus covwy 0uuw gd vkou7r5j+-; x56ymes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an og pgnllb:l,a*+u,4wz.ybh 1bbject. Describe the motion of the object.

  The acceleration of an object is inversely proportio/w 6iykfl; ufx* ri43j+z.nz3 -qvbalnal to

  A net force F accelerates a mass m with an acceleration a. If the sam.e9/rb a ln9 z;-yqcx8mnl-gro f7,ube net force is 8zx q/-lb9-yrr na,.ubf n ;g9cmleo7 applied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What acceleg.f92br pcmawcph c(j n2c9 8/ration results if a net f2phcc99jp cbc2 f a(8m/ng.wr orce 2F acts on mass 4m?

  If you blow up a balgtsw g2qy4+ m;uae .n40vvc4k loon, and then release it, the balloon will fly away. This is an i4g v 0nvye42cs u+.ktmagq;w4llustration of

  Two cars collide head-on. At every moment during the collision, the magnitude7)5xf pawprk( of the force the first car exerts on the second is exactly equal to the magnitude of the force thrwf5akp)x7 p(e second car exerts on the first. This is an example of

  If you exert a force F on an objebp1mw-2tc/08l r rf+k sm4.uahtt es*ct, the force which the object exerts on you wils. m-21/p wtscef+lu04btha8t m rr*kl

  Action-reaction forceseqe3u z9qe67 q

  Action-reaction forces 0l .mqz92eo vbph; ai5 6ei/bkare

  A 20-ton truck collides with a 1500-lb cq5w(44ph nlz;t ruto u. /kcw4ar and causes a lot of damage to the car. Since a lot of damage;/5o prt4 hncq44zlu .ww (kut is done on the car

  An object of mass m sits obnl zz cstko (-7,( e*dmxuo-+n a flat table. The Earth pulls on this object with force mg, whibd(* uzn osl-k(m7-e,ct x+ozch we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a ,j,)lc /l7rz8whv h.df 3ahq astring. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," whaafrj/,q v 3d7h wa,h)zl h8.lct is the "reaction force"?

  Your bat hits the ball pu1 +nwhw 8ry //wcqy2zitched to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose magnitud nwrcqw1wzh82 +y /y/ue is

State Newton's three la 1wes( 7j zgx9*1acokhws.

  Mass and weight

  The acceleration due to gravity dm ,xqr +2/iex9kpvw5is lower on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, w5,rp9x dkx/+v eim2 qcompared to Earth?

  An example of a force which acts atf1:wl 5lm9os qfj846wvi 7hep a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a pers m; a9w8tie7 iqkb94ts0b5uskon weighing 600 Ni7 e;u k4tist8maq90b kwb9 5s?

  A stone is thrown straight up. At the t+ ,r 0ro c8r2lryqajl1op of its path, the net force acting on it islyrrj8 0rq ol+cr2,1a

  A 20-N weight and a 5.0-N weight are dropped simulta 7focj0;z gdc ,s 2y1hob.ojb3neously from the same height. Ignore air resistance. ocg02j ;yf.ch o bd7bso,3z1jCompare their accelerations.

  A brick and a feathe.) )izde v,jtnr fall to the earth at their respective terminal velocities. Which object d,)eni. z)jtvexperiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceigkm pcc6 w4o;c6c7-szling of an elevator. The elevato 6cg; cckz p4s7com-w6r is moving up at constant speed. What is the tension in the string?

  An object of mass m is hangingl ed-joye4zeo;zd 5)t2pzyca xh5:2+ by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tension in the stl4dy cj5yz)d x2hte:az+ z e-p2e5;o oring?

  The force that keeps you from sy 3d 1,kdy )b/drjo6osliding on an icy sidewalk is

  It's more difficult to start moving aiq;z46c r6tpn heavy carton from rest than it is to keep pushi6 rpzntqc4; 6ing it with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (frit8li) rqdf, h+fws:u9ction is present) at a constant rate. h+d 9 wqf8lirfst) :,uThe 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 constant fe*3j ar xv(r g;6o4nyvelocity. Thus we can deduce (*oa4x;ef6r3y jg vnr that

  A block of mass M slides down a frictionless pla0o ky,qq;w6fd:i8 ib. vuius3 ne inclined at an angle q with the horizontal. The normalds 6i,qu ;y u3i:0fqbk8vw.io reaction force exerted by the plane on the block is

  A block of mass M slides down a ovyg 71 qz2g/ 9ri r7s4nn;iccfrictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is direc cyrv/9s7 icn7;qr4ozig2g1nted

  A block of mass M slides down a frictio/h mwr /la.lb0b,.ddvnless plane inclined at an angle q with the horizontal. The gravitational force is direcmla/ .lhdd/,.vb b0wrted

  Two toy cars (16 kg and 2.0 kg) arejya) yyti pel f,5*/;rj/u *xx released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after 5pjx;i j*//yx*f rltay,ue y) being released.

  An object sits on a frictionless surface. A 16-N fok tu 2eecl7),crce is applied to the object, and it acceleratee2e7 t) cl,kcus at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest )u eq8a;b6jjrto 27 m/s in 7.0 s. What is the average forward force on tu)a6r 8;jqjebhe car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. s e.a:w)rs2()p vpnkg What is the net force acting on the ()2eagrk.s:svw) npp body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 5g/s zo-j0rp1ok j e;w70.0 m/s after travelingow/gr;p jjse0oz1-7 k
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 y. km(sn0 zcwa, uf3r* gd0szx)ou push a 10-kg mass from rem0wz(*cxdu)g f3z n, .0kssr ast,

  What is the mass of u5 m*drx)s3u c3u8 men1lw1 ora person who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the ev)-xc4 h*v basurface of the Earth where the acceleration due to gravb) aeh v-*xcv4ity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth65mo7:;,wtm v esl( grjc7dnjdrx r-/ . What is the mass of the object on the surface of the Moon where the acceleration due to gravity i r( dr/6o w:c7 dv;xrg ent7ljs,mm5j-s only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. The Moo3wvue m3zla 8sip++n ku2l ,;on's gravity is z3elsou2+v;w8 iu3p,+nakm lone sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on ntaq.5 nw9kr /opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What tn59 /k.w aqnris 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 Fa*k tjuuy4 d33 acts on the stack, and it acceltuak d j43y*u3erates 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 e8f.2-njiovz z 0kyx6x levator. What will the scale be reading when the elevator 08.f -2xxnkizvy6j ozis accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.0 kgek:msp9 t3lku4q88j x and the elevator accelerates downward with an accelerati 38ku9etxp8sj:l km 4qon of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rim-kq -d0pyal*des in an elevator. If the mass of the person is 60.0 kg and the elevator accelerates upwad-pyka* l0m -qrd 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 of 8.0 xk 2fizk7 6bdkh;tuk5u4aa0+ N and is directed due north. Th2k60dk ;fbk ua+u5hxzak47 ite 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 rests on the flatbed of a truck. It is held 3nsdz v, 22 q6-7 ssyyzw+8uywckl9qd 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 not to slide forwau7d- +y ,z2wqw98qv s3nydls6zkcys 2rd into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in place 2tbuauwl) g ,8by metal brackets that can exert a maximum horizontal force of 9000 N. When the truck is traveling 1gu,tab w)8l2 u5 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 q2;k8 m/dqhdr M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of the2/dq 8r h;dqkm pulley.)

  In the Atwood machine shown in F*y) tbh *vgn.93dn pv.eyvv z.z dgf4.ig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the d g).zd4yv 3* ztb g.nvvf9e*.yvpn .hmass of the pulley.)

  A student pulls a box of books on a smooth horizontih, 96pwptj.n al floor with a force of 100 N pj.thp6wn 9i,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 r(s+r7y cpsm) 100 N in a direction osry7)(sm c p+rf 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 weight 100 N i 7v 96aqa7bfwtkv9x 0peeo ) /bt10*)sb erohfs supported by two ropes as shown in Fig. 4-2. What are the tensions in the r9b p6*e ovbexa0 0fa )rk1tf) / 9o7e7htwbvqsopes?

  In Fig. 4-2, if the tensions in the roj* brx/t*u(-l 5wdq6rmax4z h pes are 50 N, what is the mass of the traf5 (alz *tr 6hj-q r/mu*xdwbx4fic light?

  Two boxes of masses m and 2m are in contact with each othe yof65z 8h*ikg -l5aher on a frictionless surf8aoi* g 6hy5lzh-kef5ace. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a friction cd:4q2 looboy1gc8u :less surface. (See Fig. 4-3.) What is the net force on the more moloq:o4c:g81yd c u b2assive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the dghk *3/x mh(/d 23furzkrgord+m6x .forward force on the more massive box is F, what is the tension in the connectingg d.oz2*3xmmxkd /(hfg+h6/ u rkrd3r rope?

  Two boxes of masses m h0 3r*/gd vkry1t 6bkxand 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more 3tdgrxy vr h/1*06kbkmassive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pr*g:k j) cnwbat l 0:ov2bd) 5wmvep68ulley as shown in Fig. 4-5. Boxwb k:e*ljv)w5 d86 20rpav:)ocngb t m 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 ,msnbie6 t/* oand kinetic frictions between 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/ibs *n m,6eto is applied to the box?

  The coefficients of static and kinetic fry) )e8p4c gwtrl1qiy:dt0jc 2ictions for plastic on wood are 0.50 and 0.40,1c)48ecjrq tiy:ldgpw0 y 2)t
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 directionis *y. vt.ks3h. It slows and comes to a stop k.ht .s3s y*ivwith 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 surface is pullej1; wrzp4f hb-.9 v2kqicx. shu;zb7ad by a 5.0-N force. A 3.0-N friction fw ph b zz;c-9.fx 7aibjr1uq2k.4hs;vorce retards the motion. What is the acceleration of the object?

  A horizontal force of fr9hul; z3fky9 fw7g7,a9 oddiyu5f1 5.0 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 :3:.bbew pe qc mpcllr,6ul9s7 v+:dislides 50 m on the ice before it stops. Whatece:m3b6p cp,+ l7vl:id. : qrbuls9w is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traaffdt1,rw/ y (ffic accident, 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 conditions. Esydr t(f, wfa1/timate 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 between 9-a,*f jyq vqbthe more massive box and the horizontal surface is smooth and the surface between the boxes is rough. If the less mas- aj *fbq9yvq,sive 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.) The sur u1be6zkeremw0.f7w 5face between the more massive box and 5 ke0ezb6e7 uf1 .wrmwthe 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 boxes?

  An object is on a frictionless inclined plane. The plane is inclined at an ang)2 *1m 1bcn,w,k gkfp utqkaa4l b*,wgmka p 4ft1u2, nkkq1)cae 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 ojrls zf//2;zgle d42 q 8ldd*gf $10^{\circ}$ with the horizontal. If friction is negligible, what is the resultant force on the sled?

  A mass is placed on a smooth inclinetynsg ,( nw0r/ucy0u4 d 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 inclz c i/y oh ujc**sf:k7u(-8clxa ;*isained plane 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 directly down an inclined plane, at a constantz b4/ukk+yx*3c,l+9 cl rnjm f velocity of 6.0 nyl/jcf *xlz4r+3k+k,9cb u mm/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 axqqskm -88d(.6uun edown 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 r3- jhncowwo *5; ;hhfjomq62sough $37^{\circ}$ 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 kud4 q)osvkfrs y.5 08log weighing 500 N along a rough surface. The cable attached to the lur)8f05dv oskkq 4.s yog 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 rele2 :k 2r5jot:cw+ e:tcp bd ushos;6y-nased from rest on a rough inclined plane tilted at an angle ofwnjydb+2ctu:s chotk eo :: -6s;rp52 $33.5^{\circ}$ 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 ang sl5*g,th: ( zvenr9lqle of incline is gradually increased until the object begins to slide. The angle r:stenq* ,l9l(ghvz 5at which this occurs is q. What is the coefficient of static friction between the object and the plane?