Which of Newton's laws best explains why motorists should buckle-ukq(e- 5qg lq3j3op l8vp?

  When you sit on a chair, the resultant forcetxx. 2)4 t 5 jjya;yhdl;rg*l-p5gkgvldd9t* on you is

  In the absence of an external fo,(woqp w(wrvct n- 7+h gfnui6lk:).hrce, a moving object will

  When the rocket engines on the starkvd7/ o aatil5*cr:e4qng78vship NO-PAIN-NO-GAIN are suddenly turned off, whi 7knat:5 lv4 voq7r*gdc ea8/ile traveling in empty space, the starship will

  A rocket moves through empty space in a straight line with c93r6ayb m bmf(onstant speed. It is far from the gravitational effect of any star or planet. mm 93abrby(f6 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 buptko f-g3.e7 b.e2wc9ao )p4xojuxa( s, facing forward, and you suddenly fall forward. You can imply froj.(t xup7op .f3eaobce2g 9 )4xk -waom this that the bus's

  You are standing in a moviep67 mbtc i81d0+ *jznvd+znyng bus, facing forward, and you suddenly fall forward as6d+70+i 8cb* yvznje1dmtn pz the bus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the +tvp)ny5lig1nb)g*.shkl p 5 object.

  The acceleration of an object ion8 zr k 7mh-0n :mmhlol-lc-9s inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If tycbc4 )m wc;+w3jl/zw +bcz* the same net force is applie)* mjzbc4czy;l /+wtc3w b+cw d to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produ7p6gm/c sp4w*g z7t eft8dvf:a+,qs sces an acceleration a. What acceleration results if a net force 2F acts mvwzcqtg*deap,f ssft/7s8 7 +:6p4 g on mass 4m?

  If you blow up a balloon1d0 au vrqd828xj4fbi , and then release it, the balloon will fly away. This i f4 vqx8id8u2ra0 dj1bs an illustration of

  Two cars collide head-on. At every moment during the collision, the magnitudx3;.e.wj,ap y:fs*w;h.enmgec ;is:f g dey 9e of the force the first car exerts on the sgygcsh*s:; we3fein. :x;ejef; dy.aw p. m9, econd is exactly equal to the 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, the force whicx b,lz..tz) l+b/pyb hh the object exerts on you wilp th.z )z.b/+lyx,lbbl

  Action-reaction forceei/) b vl(s7 qry +nlqnnf20s;s

  Action-reaction forceshzy0 ba*to3f ; are

  A 20-ton truck collides with a 1500oi v)bf)a*tyj s 3i/,dq,:y xh-lb car and causes a lot of damage to the car. Since a lot of damage is done on the ca vx tyo,q/i)*s3hij: d af,b)yr

  An object of mass m sits on a flat ta4r 8.vxdqlw93 sr aonu6ue/e-am /la4ble. The Earth pulls on this object with force u4dnee// lq .o-s wlxm9 r3avaru 4a68mg, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by mevv4 k8gh747swngfm vtq 4a/(gans of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," whagn vg4t q 8f7kv7wvh/g(a44smt is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force.x6 :uhh 1 rw2ggtj/cd1 The ball hits the bat with an i/:2h jdwgr g6c1tx1 uhnstantaneous force, whose magnitude is

State Newton's three lawd725 dg bq9yspd8l4m;elyi.ey 5)q fos.

  Mass and weight

  The acceleration due to gravity is lowefzn cdx(205(i zox9vye+f q uqw+s 31br on the Moon than on Earth. Which of the following is true about the mass anzf9z1y 5vc dnw( 3xx (2ief0oqu+sq+bd weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force7rjt y7w.mf (jg2qf4m which acts at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a per*-5me z q1cgxil 2wtx ;(xy)+pa+bly mson weighinmyex1()m z p-bltx 2yqwc;a+g+5* x lig 600 N?

  A stone is thrown straight up. At the top of its path, j59lw0 ptkxc5 the net force acting on it lckp59x0w j 5tis

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same heighjx8bv9 h41kj1x(g dlf5s df;r t. Ignore air resistance. Compare their a v18gff 1xdjr5bsk4h xl(d j;9ccelerations.

  A brick and a featherwbi8nqf (;cf* fall to the earth at their respective terminal velocities. Which object expb f;8wq(ni c*feriences the greater force of air friction?

  An object of mass m is hanging by a string frovdsm fshh0- *gpey0u l0 0l+0xm the ceiling of an elevator. The elevator is movi0 0 l+0v0sdgf0u plh*exm-hsyng up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a str(r 5vnq1x *w.pc qd:-(ywzeazing from the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tension in thewn(avqyq(5pec z:dx.- zw 1*r string?

  The force that keeps you from sliding on an icy sidewa0y b0 ++zdogvhlk is

  It's more difficult to start moving a heavy carton from rest than it is to kebi ds/sbs j*n(z l:az;koi,2.imdb 47ep pushing it with constantj:ib7 2 kzd/i4alozm (n*s dbs,.;sbi velocity, because

  A horizontal force accelerates a box from res0s8fqtbu ajf+ r m 6sp.xub6+:t across a horizontal surface (friction is present) at a constant rate. The expeb0mbxaqp:+j tur.u s68 6f +sfriment 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 velocity. *3doh:i 9po tqThus we can deduceptdioq:* 39oh that

  A block of mass M slides dowc w5yvbv9bavg//v v3j+fi) glkc*:2 tn a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the block is/g2v/vb:v)clj+vct wik g5 9*y3va fb

  A block of mass M slides down a frictionless plan8xl s i;cu6e4i)*b3ktoiv q9drv+ /rre inclined at an angle q with the horizontal. The normal reactionisrr4i3l6ex8t rukv*o q;c +b)d/i 9v force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless pla1hch 3.biyo +one inclined at an angle q with the horizcohy1b h.3 i+oontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on an incline,so*q dryst() d plane that makes an angle of 30e with the horizontal. Make a statement which rs*s)(t,do yq best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied to cq7x:5i* blri the object, and it accelera ib5*lc7: ixrqtes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg ca5q*j1p+ f j2yzmxg*iw hhi,tp- f46vjn accelerate from rest to 27 m/s in 7.0 s. What is p,-vt5 j4qz1 hg2w fjmfhxpii 6j*y +*the average 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. (ya-)1a e5sgsrw5w ky What is the net force acting on the body(-5 g5)w1akssywraey?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 mkq n(e m8yzk/(m2 s-ut6zyga 1/s afte menzs((ky2-mqtk8yua61gz / r 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 mass xq,, (s5fucwbfrom rest,bxucq w,(fs5 ,

  What is the mass of a person who weighs 110z ,km5-1jjpj m lb?

  What is the mass of an object that weighs 250 N on the surface o; fltpzl:gmuq lzw)2;9 mr;d1zbm-d7 f the Earth where thdtzplmwr l)7mz;mq1 :;d lz;g u9b-2fe acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kgy46gts-akad 7 on the Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of tt6k g7sad-a4y hat on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. The Moon's m:/3t o);jixcmyy8hi gravity is one sixth of Earth's. Compare the ma xo/mcy;iih8:m3jy ) tsses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of -yfif 1 7qy2xia 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accel ff- yyqii27x1erates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictio (+i o4qob,i*ddzq2gwnless surface. A force F acts on the stack, and it accelerates at igo,bdod+wq*(qz 2i4 $3.0 \; m/s^2$. 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 elevator.tne m:/wtpv 2 21mj +,jin37lonviro- What will the scale be reading whei 1 w3mt:omnroj,ej2l2- 7/tnvn +pivn the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If pb ++an;gzifbv 69;g0qf bn. jthe mass of the person is 60.0 kg and the elevan0j9;z6abiq gfv+ nb p.f;+gb tor 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 the mass of the person is 60.0 .j nle1i 7 k zpgll,m3s17)bjukg and the elevator acc lkp1 mlsj3z,l) jbeiu7ng7.1elerates 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 forcmua 4. b7,euj qvvaisk7*k:m*coe+ 8ke has a magnitude of 8.0 N and is directed due north. The second force toward the ea4.ueb vouajak:mve8 *is7, ckk* m7 +qst 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 c8qlmd 1a.h8 j)0y/yejrzwz3. It is held in place by metal brackets that can exert a0y/d hwez qryz .8j1 c3m8a)lj 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 forward into the cab?

  An object of mass 6000 kgdtvctk97 y :crfr v4 hf)a+6r9 rests on the flatbed of a truck. It is held in place by metal brackets that can exert a maxvt 4hry9 d)ck7t6ff ra+9rvc :imum horizontal 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 machinen uo),owkb 3lev h,4w- shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the au -wwbnk ,v l43,)oheocceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shownfgejd af7g fihhcz 4l-8)*60u in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in 4 8geu7d0fji 6)f -cg*a zlfhhthe string? (Ignore friction and the mass of the pulley.)

  A student pulls a boxh+y 3bh-cxa1k of books on a smooth horizontal floor with a force of 100 N i-a kbh3y1xhc+ n 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 8wu2 iy u8g6 x s4yac46vq3gabx;ea:awosl8( on a smooth horizontal floor 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 nor c88u:2g4;xbsqw 3i6gvawxayeu a o86l4( sya mal force on the box?

  A traffic light of weight 100 Ns*:6/qb) * f eufohrdv is supported by two ropes as shown in Fig. 4-2. What are the tensions in the*6:r)s fh eo*vbudf q/ ropes?

  In Fig. 4-2, if the tensions in the rop)f;7-jzf tiq hes are 50 N, what is the mass of the traffic lfh -j7zi)t;qfight?

  Two boxes of masses m ands p / yc0-2ul)3auri;mi2f vrz 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is the2luzfyp ); /u cs3-ma0r2irvi acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictio2wh 2(9cne -oku: 4)zdqwcxkbnless surface. (See Fig. 4-3.) What is the net force on the more ma4(9zwdo:eb)nc q h2cw- kx 2kussive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-(mvc v*ul( p.i4.) If the forward foupvm(lc v*.i(rce on the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are c308ih hb3p(uaajmglys7( r 9connected by a rope. (See Fig. 4-4.) If the forward foimry 3 70aa lc93ph ghu8s((bjrce on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord runninw2/ifr-i7 im6uhv fj/ g over a pulley as shown in Fig. 4-5. Box I jf76wh/v-/ iirufi2m 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 stzn/ 2uppt) hz,p iy)m/atic and kinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net forcpitz,) pyz 2n)/mh/pue on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on39xvkg ,g ko: 6aijyfu l*67zd wood are 0.50 and 0.4g3 ja*yk ol,6u :v9kdx6fi7gz0,
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 andmsul/sdvd *3, )sc d9e comes to a stop with a constant accd9,ld 3/msssucd) ev *eleration 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 pulled by a 5x(/ q.- epafp*+qpzzy .0-N force. A 3.0-N friction force retards the motz-.(p yp q*a/qzxf p+eion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest, at a hd ru+ygky 9rt9: xxd3u.4s:y 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 50 u8a 5m2/gaq;4b0ey d qoi9ivb m on5 qq4yv2 u0igab/i m;b doea89 the ice before it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of ardd;w 8u20 yb+zf yi4e traffic accident, police find skid marks 90.0 m long. They determu+2 yz84ed wb;rf0yid ine 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 t 9xhc2v,/m21,jgbasqruv 2bm and 3m are stacked. (See Fig. 4-6.) The surface between the more mas 2rxsbmv,b,g9vt1 cja2qu2 /hsive 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.) Thl 1/jp- eb+vp5o*)o+ gwa wxxde 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 fr+wv*/w ab px 5+dopl-j1exgo)iction between the boxes?

  An object is on a frictionless inc0n5q+s mhjk p1c4 8atelined plane. The plane is inclined at an angle of t a q nj0mh54k1esc8+p$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides do54oolpui i 4h*wn a 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 ihlgf(* q0e dsba1awc(+)xo7 s hfk r24nclined 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 inclined plane tilted 5te ryvyr1 0w ;xp64gktr2kc*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 v r2+b(d,jtq ajelocity of 6.0 mrd+jjb2t (q, a/s.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a massefz 7j)++n loo m 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 slides down yv 0crwzjlw(/7u-7au 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 alongd nx r:f53r2xe a rough surface. The cable attached x xed23nf: r5rto 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 inclined plane tiyv:tdd( w w)c:mdi.:mlted at an angle t:d :: m.dwdv(wmicy) of $33.5^{\circ}$ 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 inc7idvg.f4l8v xlined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficientigv 7l.f4v8xd of static friction between the object and the plane?