Which of Newton's laws best explains ) rub6cnlj16iwhy motorists should buckle-up?

  When you sit on a chair, the resultant force on you is jk41 *skd97cg-fhnt cipaq* /

  In the absence of an7ch w /ie/eht-m pz9+:wsur;x external force, a moving object will

  When the rocket engines on the starsmifw 8mftn;)q. 2 a-goohc2u /gk*h0i hip NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, the starship willn) gik.oi*0o-mqu;fh w /hat2 c82mgf

  A rocket moves through empty space in j zfz gn.43ix0gw njo4(*5tnb a straight line with constant speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocket in order t3j 0zw5.4fgg j bton n(4x*nzio sustain its motion is

  You are standing in a moving busxz y qqx q9*29;yp8nyzd-k x(ab:c(ww, facing forward, and you suddenly fall forward. You qx(-;d99 pac8yz2n*w y(k:ybx zqw xqcan imply from this that the bus's

  You are standing in a moving bus, facing forward, and you suddenly fall foa) hzf1(fpbe3q lc )(grward as the bus comes to an immediate stop.pcalgb3f(1)eq )h(f z What force caused you to fall forward?

  A constant net force acts on an object. Describe the9m9 ls x+7kx5bgv)f vz motion of the object.

  The acceleration of an object is inversely pr;zh zty+m5ad o 5*8koloportional to

  A net force F accelerates a mass m with an acceleration a. If the same ne ak 8zdw sz.bf;7ji0oh-/h)kwt force is applied to mass 2m, then the accelerats h7akf0 -owbiz/hzk d8; .w)jion will be

  A net force F acts on a mass m and produces an accelerati* yfn; tnyi.cv.g.au4 on a. What acceleration results if a net force 2F acts .*.in4g; a.cytyf uvnon mass 4m?

  If you blow up a balloon, and then re)4isgw. sen ,xc9 ls.mlease it, the balloon will fly away. This is an illustrwm9xsi,.. snsc 4e)gl ation of

  Two cars collide head-on. At every moment dg ,ft 6yjonh);uring the collision, the magnitude of the force the first car exerts on the second is exactly oygjhtn6;) f, 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 objecty k6*tfdoto693 lh: x8)guxsx, the force which the object exerts on you wioy 9f x t th):l38sogxxuk6d*6ll

  Action-reaction force g01ed:qtq h pkjqeoh lh6sve*v1* k,ja /m*/;s

  Action-reaction forces3xmj2a eb.*,uxaj b b, are

  A 20-ton truck collides with a 1500-lb car and caus )6 7lkyfdvg*yes a lot of damage to the car. Since a lot of damage is done onf6lvky ) dg*7y the car

  An object of mass m sits on a flat table. The Earth pulls on this object with(4)d0v h ne0i/yzqsq y force mg, which we will call the action force. What is t 0ed (4zh)ni/vy0qyqs he reaction force?

  A child's toy is suspended from the ceiling by means of a string. u5t pljz2b) .s The Earth pulls downward on the toy with suljt z).p25b 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 witl7ui 7ukx pb0+h a 1500-N instantaneous force. The ball hits the xp7li0ku+u7 bbat with an instantaneous force, whose magnitude is

State Newton's three laws.th9 /ln8,ym lros:f/r

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Whichz6jj1ry d-.uyl dw :xlq 1f79m of the following is true about the ma-6 :7lddj.11yqx ymwzfruj 9 lss and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a dista2q rptk:;vfwx9t r1 o,ik2.spnce is

  Who has a greater weig::kgekni-9* l*+i7ls2k tf wmbs -otwy2dfn3ht to mass ratio, a person weighing 400 N or a person weighing 600 N? os:ybw iw3*knge9ntk-lidl+ m7*2 sftf2 k:-

  A stone is thrown straight up. At the top of its path,ozi,k l lw ao(d7-ppnd4x-8, ddm2wm5 the net force acting on it ol5i nz wd -dm-d8a4pw 27pxd,m,ko(lis

  A 20-N weight and a 5.0-N weig i3 kkw8bskemp*5 l0s7ht are dropped simultaneously from the same height. Ignore air resista wkkelips 0b*35 s7km8nce. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal vr1r80up7x2q x aj1jtvelocities. 8q17vxx2jpt0rrj u1a Which object experiences the greater force of air friction?

  An object of mass m is hanging by a stgvbrl 985yku( ring from the ceiling of an elevator. The elevator is moving up at constant speed. What kybg (urlv958 is the tension in the string?

  An object of mass m is hanging by a string from the ceilj0m)jsjjd;w k i29 cn9 h32nluing of an elevator. The eleu02jlw) 99hsnckjji 2mjn d3; vator is moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy g1a w -01jjhgov)si+q sidewalk is

  It's more difficult to start moving a heavy carton fru buzgeu y-v7,3pk*l0bl/ /i rom rest than it is to keep pushing it wb - e3upz/uiuy/* kr, lvgb70lith constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (tazjrx. -5z d0u9 eyy;friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with thdt ;9ejzuyy.x 0r 5az-e exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constaet-7;ov+piorr ,*7q ch gnqk0nt velocity. Thus we can deducqqk ,ci*77ht0 r;-og erv+onp e that

  A block of mass M slides .uggz1t rbn ,9down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the planeng r gzu,1b.9t on the block is

  A block of mass M slide*lf07h3lj;a u 0 wwshzt1 *sgjs down a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by t3j1ulwa 0 gh;lz*jw7ssth *0 fhe plane on the block is directed

  A block of mass M slides down a frictionless plane inclined s 28pg+r8j2lzb-yuqth,leh 3 at an angle q with the horizontal. Th jh l8 hr3us-zl tgypq22,e8b+e gravitational force is directed

  Two toy cars (16 kg and :x7; j4jf/aaahmd9ns2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration aft;: xf a a9mas7jhdj/4ner being released.

  An object sits on a frictionless surface. f+pcmvd 86 -gwnn*u v;;jwb o(A 16-N force is applied to the object, anb;nm wog6n+;j vw-d(vu 8pcf*d it accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1)rt2qrs t6*q;a826 *knduj9a ,ob .llfydqtn000 kg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward force on the6qd9 ;n8 *2j)d y a ort*2,stluftrbkq6qln.a car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 ys-*vb-1 iwe p ,ecb+zs. What is the ni-+w*z,ve1sp -y b cebet force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a 4cq6cv l7 hg6+ejvk) ispeed of 50.0 m/s after trave+qgjecl)ch k4iv 6 v67ling
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-kcmp l7 i)re0o:g mass from reslie0 c)7porm:t,

  What is the mass of a person wh z;kooqld8*igg 6+g(x(v nsy* o weighs 110 lb?

  What is the mass of an object that weighs 250 N on thesfxp g4)5 ic;e surface of the Earth where the acceleration due to gravity ; f45 eipg)scxis $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. t iqtb/2h2ptx o*9cn/ What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of that 2b *t9pic /2tq/ontxh on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moona6 x ub,tcbqp9dp/yq:l7(v;v. The Moon's gravity is one sixth of bq, pavt9pc;b7x ud/6yql v: (Earth's. Compare the masses of the objects.

  Sue and Sean are haviva85)z peuwz; x-r9ur ng a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Seazrur-9a8 z p)euvw5x;n's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless sy x*x9 l43fem2).h:5 0ncq xmllrxpp burface. A force F acts on the stack, an)lhxp5:q .4lyprn0 lxc2 mf 3bxxme 9*d 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 ele,) e(/ likcow6,n :sarj5p gfmvator. What will the scale be reading when the elevator ipc5(,/n,r)l:w 6i m kgjsoefas accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. Ifazm*/m93 .rn g b0w08rl;e-psn.bt cakdna: f the mass of the person is 60.0 kg and the elevator accelerates downward with an ac0nrn*-m e8k;pf:aaws .cab ngl mrt./9d 30zbceleration 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 60.0yg(;yy)1npdpjff 5-f kg and the elevator accelerates upward with an accelep;5f y 1(gy pydf-)fnjration 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 v 4 nkehp/va*rl0dz6: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 acceleration of*elpr:d 6 ankvv4 /h0z the mass?

  An object of mass 6000 kg rests on the ffr8ee1v a n p )-;r:c+uugjt,wlatbed 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, 1+gpr,e8u etwu)c- j:;fvanr what is the minimum stopping distance if the load is not to slide forward into the cab?

  An object of mass 6000 kg rests on the flatb3;+ tq92.ca wfep ku-vfiu4ia ed of a truck. It is held in place by metal brackets thu ;u2 fae4fitwiq. 3kapcv +9-at 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 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.t(k(m 5i*cing: 7b nru40 kg, what isr *5n: nc7 (gbk(uitim the magnitude of the acceleration 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 = 0.46*+ bfmqdg-d3r 5wvz y0 kg, what is the tension in the string? (Ignore frictio5vqd6rd+gfwz *bym -3n and the mass of the pulley.)

  A student pulls a box of books on a drku5* dp r5/xsmooth horizontal floor with a force of 100 N in x5 r*5prd d/kua 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 boofseh:q9:jnf, isbc) 4ks on a smooth horizontal floor with a force of 100 N in ):,cb94qf hfssne ij: a direction of 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 issan g xyok, 1r,q6jt;/ supported by two ropes as shown in Fig. 4-2. What are the tensions6q ntg,r1yx sk,joa;/ in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of the tlg9-l q:9z1g wp, e.ozbj jo;nraffic bnw g .-o1 9pq:,jlzog;lz9ej light?

  Two boxes of masses m and 2m are in contact with each other on a friqk*/-2 1 h+ vfenvsj; m)*elfb:nztxxctionless surface. (See Fig. 4-3.) What is the acceleration of the )bhv*fntslzn +fm-ex;/ 1q2k vxej:* more massive box?

  Two boxes of masses m and 2m are in contact with each other on a frictionlesse k yeh94ev9m- surface. (See Fig. 4-3.) What is the net force onk4y-mvh ee9e 9 the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fcg-ke im; t2:fig. 4-4.) If the forward force on the more massive box is F, what is the tencf2 :-m gek;itsion in the connecting rope?

  Two boxes of masses m and 2m are connected by a obge9o+ i3s5k tne0b3rope. (See Fig. 4-4.) If the forward force on the more massivonst935b+3i kego0eb e box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown i5p3 ts ( ;5 znippxslkaacz/c;f;v(w-n Fig. 4-5. Box I of ( -fvxiz/(c;;lpz;5stacp 3 wnsa p k5mass
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 bgj 7nq o 2/h+oupq4fn4n 3bzi+etween 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 horizn z+p4f ob4q7 2njnuio+/h3gqontal force is applied to the box?

  The coefficients of static and kinetic frictingh539:qygkvtizr/ 0)oa7j k ons for plastic on wood are 0.50 ana9kg:35ihozv 7g 0rjqk)t /nyd 0.40,
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 +dg;2 ab6fd g.jx direction. It slows and comes to a stop with a constant accejb6g.2d;dfg a leration 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 suyxn*pp0-co) k2agz m5rface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the acceleration of the p2y-kaoxc 0gnp)zm5 *object?

  A horizontal force of h0 15dc bd/i*z73kuz wirkvdp wk.r3,5.0 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 a*(2u)eqd su4 tj a*4ng lkk-k,/labdspeed of 10 m/s. It slides 50 m on the ice before it stops. What is the bat4k, na2* k-4 gjsud*a euqd/(k)l lcoefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police find ski:+abuwgkkozhl 08hr;- f:t l ,d marks 90.0 m long. They determine the coefficient of friction between the car's tzwbl -a;f:h o0hlg ,+8u: rkktires 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 b2d7:ar xl:d, edex.band 3m are stacked. (See Fig. 4-6.) The surface between the more massivrdbxd 7e:2xb.:ld, eae 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 stw(80r exyj ooe+n(2e backed. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth and the surface betweene+eyejr(owo n 082(bx 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 fricts8 k;yd/4ava nionless inclined plane. The plane is inclined at an angle yns/ av a48d;kof $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hbxo9-9 f ;zortill 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 wi8x7 aq-a;j sruth 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 tilt.s:.2klzp xjr:i,r7mnh 3dt bed 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 inclinrcb 3 up36 u8r:dtnb3ged plane, at a constant velocity of 6.0 d:3pnb r836 ubugt3crm/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 down y/tj*te q q:-la 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 fcz/:-yuel.h m slides 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 aluzsc0)n25mdr ong a rough surface. The cable attached to the log makes an angle)zd 2crs50n mu 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 :hc0r6a4- pm;5dygjy:i zb j afrom rest on a rough inclined plane tilted at an angle of064b-aa :jhp 5z;gy cyjdri:m $33.5^{\circ}$ 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 t z44 dt9 jkn59ilw(trangle 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 the object and the pl t tj w9d(4nzlt9kr5i4ane?