Which of Newton's laws best explains w5b0h-k fr:7pwbt/ei o hy motorists should buckle-up?

  When you sit on a chair, the res3n32m*5bmqb lkw xbpv +jr;1pultant force on you is

  In the absence of an external force, a moving object h4og*irks vz-uf;-gw+tcp1)3u ;skz will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are sunknbqoa7rfn-7 5og-tc,)io6 ddenly turned off, while traveling q7n ia to6 nc-rk7fg5no-, ob)in empty space, the starship will

  A rocket moves through emptu/+:;, 9sznaz8 afjm c2rgpvcy space in a straight line with constant speed. It is far from the gravitational effect of any star or planezpaczugr jn +ac,f2m/;s8 9v:t. 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 suddenly falll.q- 5e0 tuniz forward. You can imply from this that t -l5 u0q.tenizhe bus's

  You are standing in a+a *e8 bphso-e moving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. Wha8- *+o hepaesbt force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the objectl26lul n/8cz buw35 ,y:;ao n80 4xrsnceow mm.

  The acceleration of y4i9cw/(jcq yan object is inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If t3xqcc o n1g/,0z*wd khhe same net force is applied to mass 2m, then the acceleran0k h3gdqxcz/ cw*,1 otion will be

  A net force F acts on a mass m and produces an acceleration a. Wb93tk/r n duh-hat acceleration /dbh-ukn3 r9 tresults if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fj7 ,scy d.fr8.;s(dstwqka-mly away. This is m..fkcsq 7y(d,drt;sj -a ws8 an illustration of

  Two cars collide head-on. At ev9pgw;eam0t,4 t*u32 q kzelsrxtg59m ery moment during the collision, 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 first. Thig*k, 0rmtu4m9ts9qx 3;apzlw 5ee2 gts is an example of

  If you exert a force F on an object, the f*pw(ewx,h;pcucq0; (1 ctqc b orce which the object exerts on you wi(hc*pt, w1;qxq w pc (cc;eu0bll

  Action-reaction forcq;e+(yi4 5ct gy/yo5ntf 9kkues

  Action-reaction force*kirlbs tm:q sna:f33v* s9/ul+/aul s are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage to j; *otczt9h g)j+(sbjthe car. Sinc *g9)h jj;tobs c+zj(te a lot of damage is done on the car

  An object of mass m sits on a flat tn xuv.33s7l5* y6tbqjcjlfw qyo0x 6:able. The Earth pulls on this object with force mg, which we will call the action force. Wyqc63xjl5:b7 qxnwu 0 lfv*y so6.t3 jhat is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The t:wy hbi q*w6+Earth pulls downward on the toy with it 6t+ wy*:ihbwqs 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-N instantaneouod g6mcwp, 7f;s force. The ball hits the bat with an i;wc ,f76 gpmdonstantaneous force, whose magnitude is

State Newton's three lqt mty7ry ,: 5lpt(,b-waqu qxfj/87laws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which of/t h6vrio91jq the following is true about the mass and weight of an astronaut on the Moon's surfac q/v61j9 iohrte, compared to Earth?

  An example of a force which acts at a icr+lcqhtw5xk1pby 27nf(v3jas-6 5distance is

  Who has a greater weight to mass ratio, a person wei r4om;.8 0n6g)sallq 9 bvwb+uh czcb4ghing 400 N or a person weighing 6c +8o4m )wlgbbrvul;0asb nz49q6c.h00 N?

  A stone is thrown straight up. At the top of it8 h*kdr/l b:xhy jr35gs path, the net force acting on ik/*hy:j5 g3rxr8hl bdt is

  A 20-N weight and a 5.0-N weight au; mh*vtm(hiq)2 )k a,bemxf*re dropped simultaneously from the same height. Ignore ai; ha 2*k )qht(mvbife,mm)*uxr resistance. Compare their accelerations.

  A brick and a feather fall to the earth at thv zqarb.+: k0xeir respective terminal velocities. Which object experiences tq.x0vkz rba+:he greater force of air friction?

  An object of mass m is hangihe7k1jmmue u 0k98oh:h *m g3ngr,6mxng by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tension in the sth*1m36 e07hx, 9mmgekgok:rh8numuj ring?

  An object of mass m is*:7-j 7yhu9gjmrictw hanging by a string from the ceiling of an elevator. The elevator is moving upward, but slowin-hg7 j9 7*umt j:wcriyg down. What is the tension in the string?

  The force that keeps you from sliding on an icy sli7f,b hyb-9 yidewalk is

  It's more difficult tofbu*p q7 :)idd start moving a heavy carton from rest than it is to keep pushing it with constant velocity, bed :qi*fd7p bu)cause

  A horizontal force accelerates a box from rest across a horizou am+j0m a7)2 blnxo3nntal surface (friction is present) at a conaanub3)2 x+m 0mno7ljstant rate. The 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 veloces 4cj,0fmsa4 w.s phk +1l4ocity. Thus we can deduce that4 ss lmp+s0f,e4ko4h j 1.wcca

  A block of mass M slides down a frictionless plane iz97qy :ae)tp6o: x fzik6u6nin*7ffk nclined at an angle q with the horizontal. The normal reaction force exerted by the plane p:z6 6ke)qi7yx*on fufnk6 z:at9 i7fon the block is

  A block of mass M slides down a fricbm 80epb)w/ppb14ib/ xz obi2tionless plane inclined at an angle q with the horizontal. The normal rea ip)/0 e8pbz2w4i/xpb1bbobmction force exerted by the plane on the block is directed

  A block of mass M slides down a fricti nbz* 1m6 o5yxymwuajs b7,+5ie3l y1monless plane inclined at an angle q with the horizontal.eno*s6xyl1mw ,+mb 35bz7ja5yy1m iu The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simuvefxmt(+ 4 /:y.2i y kvfpu,fc7raz 9hltaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acc2kv7cfv,: +eatx( i4ypyffu9 rm /. hzeleration after being released.

  An object sits on a frictionless surface. A 16-N vl(v-kg);th aforce is applied to the object, and it accelerate-a vgth)vkl;(s at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to : qxujt7 ;n my)/5sezb27 m/s in 7.0 s. What is the average f z ; )jy7bns:etqxu/m5orward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0pjm t++bqd:xg vehu 4f z1kwf0i rk(2z;)jv /7 s. What is the net forcf2j(ujhw;v/ di)txm: 1 fg+0qkve r+b zz74k pe acting on the body?

  An antitank weapon fires a 3.00r)p:6fap4t 8toty ,dp-kg rocket which acquires a speed of 50.0 m/s after travetp,)y atfo6pp 4d8t r:ling
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 -n7. t4jci0i2yu o .10l my3med wuthoforce that you push a 10-kg mass from rest l4-0 du2ytiu wm3yn moi.7.ect0j ho1,

  What is the mass of a person who weigis (7t.om u w9jg/p5eghs 110 lb?

  What is the mass of an object that weighs 250 N on the surf+,ql azgj)u 80 3zrbewace of the Earth where the acceleration due to gravia8,jz0egu) lqz+br3 wty is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. Whatv+v f)8bhk(y m is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of tha+hv8y) bvfk( mt on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. The Moon'zx+ozla*- kjc j4nv(ki 8s(*d s gravity is one sixth of Earth's. Compand 4i8 l(s* kzkj-*+xa(jvc ozre the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite esvm,(dd4hw 7lfs6 fp,nds of a 5.0-kg rope. Sue6mpdf s,s, 7fhv(d4w l pulls with a 15-N force. What is Sean's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surfia hl(/f91bop ace. A force F acts on the stack, andb(f/a9oi p1hl 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 elevatoi*b1 5iptpi be ,:zz5nr. What will the scale be reading when the elevator is accelerating downward at z*e:bbz pn5,5i 1ti ip$4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the pe8,k 7d.0 )dhfpu nhwnmrson is 60.0 kg and the elevator accelerates downward wit.),uw0d8khhnmpn d 7fh an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an elevato. *wqwbk7dn +)4-e/nnzklg xir. If the mass of the person is 60.0 kg and the elevq z7i.-+wk*xwl n k)bn/d en4gator 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 has a magidmz:zns m9 + azam2 ix,k3s3y:d;gm+zmz- 0hnitude of 8.0 N and is directed due north. The second +, 3z mizi3+m2az 9mmka0zs h-dzdy :;sm:nxgforce toward the east has a magnitude of 6.0 N. What is the acceleration of the mass?

  An object of mass 6000 kgtjz5nag;) *4 *ts duuys a87xj rests on the flatbed of a truck. It is held in place by metal brackets that can exert ;n8* 4s7d t)tx*z gsaajuuyj5a 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 kg rests on the flatbed of a truck. It is held 7l1hs,hi k:u mch-dv: in place by m ivk:,1 :sh-7ldhuhcmetal 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 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 = 0.40 kzmh5v;sydvmk5 p)d5gp//(rt g/wnav56 vg;g g, what is the magnitude of the acceleraktp ggv)vmrg p5/h;;w5n d /d5(g/z 6m s5yvavtion of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1m ugb/baa4junx v1;./, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the ax4 b1.vn; gu m/bau/jmass of the pulley.)

  A student pulls a boxww n +4-ceowpx(zkpne */6la0 of books on a smooth horizontal floor with a force of 100 N inkop-*ac(x0zwpe6/w 4+n nlwe 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 horidc4efg2 (n aep*8wuz8jw k 47rl 5lxb:zontal floor with a force of 100 N in a directinwg8cw4 a2dkbxr7u( f8zje 5* el:pl4on 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 is supporte)fxvjk0 *ir v+d by two ropes as shown in Fig. 4-2. What av i vkr0*x+jf)re the tensions in the ropes?

  In Fig. 4-2, if the tensionszz 01adpusp 1(q9udg0 szn0u1 in the ropes are 50 N, what is the mass of the traffic ligha0119uus zzqd0p d1pn (0 zgsut?

  Two boxes of masses m and 2m are in contact with each other on a fric:ic 8zor7uv+6 cnr0ql tionless surface. (See Fig. 4-3.) What nro08:irzcc7+q6uvl is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact withx9w6b y -t6w2uimzbt9;s) bmg each other on a frictionless surface. (See Fig. 4-3.) What is thex)9w6 su; t6- zg 9b2tiwmbbmy net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Ff7b b ree c0)auko1j +i.4cpb7x-gajfx zx2-1 ig. 4-4.) If the forward force on the more mxr f 2ep7k 0c4bxfuej 1- 7bzabajxo+c. )gi1-assive 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 thek0v3aen:mw1n forward force on the mom:1 ae vnk0nw3re massive 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 in Fig. ))k 97xwhar nu4-5. Boxr7 kxau )n9)hw 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 stpv.; zs6gomilyyi9/ hkp*a :)atic and 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 is applied to ty. phl9:zvm)i iagp;yso *k/6he box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.5am0pv)0zjs3kfv(4u 6 y j/by b0 and 0.40sbjk) p(bz4um y/6v 3v0yaf j0,
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 survnnz. h,z9 n tlly +z9o8h+)xtface in the +x direction. It slows and comes to a stop with a constant accele ,yn)ovtt89n.z+z9h l+n lxh zration 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 pd8bgl*h .f 30y,x8 v;8mcoaxfqbm4wis pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What is the 4 q 3*amlxf o8xpg bmhdwb y80;c.8,vfacceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mw eluv69xyq37 s-li2q ass, 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,j;g ;me/qp4 yv a puck is given an initial speed of 10 m/s. It slides 50 m on the eqjy;mg;4 /pvice before it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigas w3c cn)mu-oh fmi153tion of a traffic accident, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's ti i)5swc mnf-m3ho3u1cres 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 and 3m are stacked. (S+t * v+)d0owy9ttwwnvee 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 static frictw wv0vdt +) *to9tw+ynion force on the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surfac df3d(y*;lb v+ kcbn1l fsn;6be 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 frictionbf ncsbdb l *(1;dv;6yfn3+lk between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined nlwl8 cu(hke0x )j6h 3at an angle of 0nxh8llh)u (j6 wcke3 $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a f c/krfsvrtj + b +r).wlwo80c53c8 xb9/nswpz lat 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 dgv yd gju1r 8k,m7e/q37c2ltan 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 i0:pmpuy23i 3pipp io2nclined 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 dire hp2 ;lj0pphb8wdo 2mxl+ f/+ectly down an inclined plane, at a constant velocity of 6.0 m o;wep+2jpp/hf2lh+d xl0b 8 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 mass7 q)wtn nuag/) 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 a rou2uh+zn(y.ev +shwtb z;:el35 k qvd9kgh $37^{\circ}$ 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 surface. py8u(4 z t6aduThe cable attachea4zu dt( y6pu8d to 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 releg1x t97h((cvx;cb cphr3 .h qlased from rest on a rough inclined plane tilted at an anglepb(lh.ccx h7t31q 9(chxg;rv 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 tb52zc:kwk 5yan inclined plane. The angle of incline is gradually increased until the object begins to slide. Thecky5bw52 z:kt angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?