Which of Newton's laws best explains why motorists shoul w; 8ugpp2q, liicr 7cvnj1/6ld buckle-up?

  When you sit on a chair, the res zsvp38 9f/vmzez1g+ jultant force on you is

  In the absence of an external fo,*(l ggecq /gp4vou(i whs +.orce, a moving object will

  When the rocket engines on the starship NO7me/mifkzd()j. *kme7,t .zx 7wisvf-PAIN-NO-GAIN are suddenly turned off, while traveling in empty spaiz m7(/. d kf7 7fzmjekites .)v*m,xwce, the starship will

  A rocket moves throucfa8v+nu1p- 5 vv uzu+gh empty space in 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 to sustain1pcv fvau u+v5 +-u8zn its motion is

  You are standing in 6z fap*zz,)mwg zcgaay-25(ia moving bus, facing forward, and you suddenly fall forward. You can imply from am(,6paaz2)zy 5 *fi g-gwzczthis that the bus's

  You are standing in a 7b9-i,x.eaksgez akm -mej,8 moving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. What force caused you to87eaa-9 exzj megk-skmi, b., fall forward?

  A constant net force acts on an object. Desc wji2euxvq,l5. huh/ ,h a(-qjribe the motion of the object.

  The acceleration of an object is inversely proportional tq f7zes huy.+jvn0hl l8 ((b0ko

  A net force F accelerates a mass m with an acceleration a. If th(vgjzickxn27i 8s,z8g7kz ri;3 )ft 1nv 5viae same net force is applied arzc7 zs81n)j2zt3n ggf7, vv8 ik(5kiivxi; to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an ,v4ez336gj-iu mb vzv acceleration a. What acceleration results if a net force 2F acts on 4v gj33mbv,iz e uv6-zmass 4m?

  If you blow up a balloon, and then release it, the balloon wis :gm5o//joot/qi, fcll fly away. This is an/:gsf,/ jqooio c5/t m illustration of

  Two cars collide head-on. At 1:) kz ,bvizrmr+p9ie(ukv 9nevery 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. This iskz ib( krei 9vp9r1)m:v+n,zu an example of

  If you exert a force F on an object, the force whichzvzh .wp0um,hm81 :gtl.ei y m 8b-cy: the object exerts on you willu1gby.,hwv8 8zmhml.0z-p: m c: e tyi

  Action-reaction forcedusrnc,;u8c-hh2u :,vqa y 8ys

  Action-reaction forcbliiv/ o3f 7nmdnf00, es are

  A 20-ton truck collides with a 1500-*5i5 o t 5thjjeehhu9 ig3s*/ulb car and causes a lot of damage to the car. Since a lot of damage is done on et3 juu5*soig5hj9*e t5 ihh/the car

  An object of mass m sits on a flat table. The Earth puac+irgoeu6ji -01e:uoo pcq 0 p*.; pwlls on this object with force mg, whr qu*:jce i-c10a6 po. u0p+;opgi oewich we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string0rgp3 )7dtbl(vv a8tj. The Earth pulls downward on the toy with its we jd0vrp ta)vg(38b tl7ight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ballyae x r5gk3/m. pitched to you with a 1500-N instantaneous force. The ball hits the bat with an instantaneous force, whose ma y3m5e .r/kgaxgnitude is

State Newton's threed9xe,yqb1 -g : m+ey,8aeh wrc laws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Ear3e78 tmpvnhe* th. Which of the following is true about the mass and weight of an astronaut on the Mo3* ntm87vh eepon's surface, compared to Earth?

  An example of a force which acts a s8e /q3najz*st a distance is

  Who has a greater we um43v0p/.a )tiw o rsh.iccf1ight to mass ratio, a person weighing 400 N or a person weighing 600 N? )cu vi 1i h.r.cfwa0t4sopm/3

  A stone is thrown straight up. At the top of its path, the n93f *gk msi07p0euatnet force acting on itfpak7 g0u3*nem0s9i t is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the samesdd (ssl55 /sk height. Ig5s (k5dlsd /ssnore air resistance. Compare their accelerations.

  A brick and a feather fall to tgka9 )l l9c93qjjsp4 rhe earth at their respective terminal velocities. Whi3r) a lc4kj9gpq l9s9jch object experiences the greater force of air friction?

  An object of mass m is h,8rbp. q v8ujfanging by a string from the ceiling of an elevator. The elevator is moving up at co,j8b.f8 prqvunstant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of ab*rdvp nsp7;+c 13wmm;m9qu h n elevator. The elevator is moving upward, but slowing down. What is the teh m9pmb+pq1uvn;w* ;r cs73md nsion in the string?

  The force that keeps you from sliding on an icy sqd;w qd+yi ++ti1/9i; syagncidewalk is

  It's more difficult to start m,t14u yh slydaq;:yt0fc -og9oving a heavy carton from rest than it is to keep pushing it with const:d yyogl tq,0 ya-c14h 9fs;tuant velocity, because

  A horizontal force acceler 9fbjfdk 5a7 li-89 nf),rclm6 xk1ptsgxas4(ates a box from rest across a horizontal surface (friction is present) at a constasc i8a (-lkakf45)tfjd xrb1p 9f,mg97 nxl6snt 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 inclin gh nemrqg8/1)0z2l yqed ramp at constant velocity. Thus we can deduce thatmn/ 820rygl z1qeqhg )

  A block of mass M slides down a fricti v*di2,askbf -onless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plbfi*k v, 2s-adane on the block is

  A block of mass M slides down a frictionless plane inclinezx ;2p1gku uwgx233f *m0wi gnd at an angle q with the horizontal. The normal reaction force exerted by g2wxw0zk g 31ig2xup ;fm* 3nuthe plane on the block is directed

  A block of mass M slid fa+ (aitpgc0 )em4*vses down a frictionless plane inclined at an angle q with the horizontal. The gravitational fortcpeis(f*g)m aa0v4+ce is directed

  Two toy cars (16 kg and 2.0 kg) are released simtoe14f/vzcyr g jy 0-n)vzy:)ultaneously on an inclined plane that makes an angle of 30e wonvg4vjczry0)/t)1y :e-z fyith the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a friction u5cozxp o(rmap-0mry0( b0 6aless surface. A 16-N force is applied to the object, an-a5yr0 zx(0omr (pc up6m 0oabd it accelerates 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 27 m/s**izazee8o 3 q in 7.0 s. What is the average forward *aeizq3z 8o*e force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.04jh;n lp06xi h3yk1 fg s. What is the net force a3;xl hhn6 k0i j4py1fgcting on the body?

  An antitank weapon fires a 3.00-kg rocket which acq+4 xg .ksj(qwbzr-zz reeu0 ,2uires a speed of 50.0 m/s after travej4zz0x+q,zusrr gb( -e2wk. eling
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 witv7 j6vque8x, )sz.aq7xdhg+ kh the same force that you push a 10-kg mass from rest,eqas)z77 vdv q8. h6,xjkgu+x

  What is the mass of a person who weighsdfjk p-p ;:zw4w 7d2f f4+xm-m-gkvhv 110 lb?

  What is the mass of an object that weighs 250 w .b;a wuyq+.oN on the surface of the Earth where the a.q; +youwba.w cceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass osc98) g57x4c y x 7vv1x ffyf-djn+. qzi8vmgxf the object on the surface fdi977jf xfq vm g-vgx)yz.14 8vs85 c +nyxxcof the Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on 6 8g d:ixot*pnecnr tqnw3h6;t g50z:the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of the objects.nnd:8ge6 *th;rw5g x6qttoi3cnz0: p

  Sue and Sean are having a tug-of-waxwqz, e b5-h9h(r2(bofuc (lur by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope xoc-qhe ((l uhf2 wbzb(9r5,uaccelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictio2yspkg xkpi,* )wa rqnm)2*w .nless surface. A force F acts on the stack, and it acceleratesw2kpq,)**s).m w k niya grx2p 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 N8y+ bnx nbe83, qbacu; stands on a scale in an elevator. What will the scale be readx nbbu3eb;8n,yqca8+ing when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator.ann a3, .jbv ob0wefl4ma-i,: If the mass of the person is 60.0 kg and the elevator accelerates downward with an acceler3maa,0,af e -ojbi.b:vnnwl 4ation of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in an 59bnhlq 7y/o jelevator. If the mass of the person is 60.0 kg and the elevayo7b9 5nh/q jltor accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5tux7 tvx8l +h u) w4pnbf7p2y,.0-kg mass. One force has a 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 th7 t2 p)ynt,l4pxuvh+x87w buf e mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is heldl68yn-sm, icg in place by metmy, i-s8 nglc6al 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 forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is hez tbx5p-9z(ln17y pmro,xe2 ald in place by metal brackets that can exert a maximum horizontal force of72p(tyxzxbl-n e 9m,ao1z 5pr 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 kg, r,gs;kc. y jg;-mhr+r5g;co i what is the magnitude of the acceleration of the j-5crrh i sg; r.gckoy,g;m+; system? (Ignore friction and the mass of the pulley.)

  In the Atwood machinems66/ lb 5zody4 nnoe2 shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignom 5/z els2noo4b6d6nyre friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of 100 jsh*as-c z(e e7sy; -k+lw.arN in arss;ce h +*.wzk--ea( 7jlysa 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 6t h .+e5svso*ri:xoe force of 100 N in a direction of 37.0e above the horizontal. If5es6.hoe t+rio*xvs : 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 supported by two ropes as sh1)5tjxauz/uk3p)q3) n. h 1rdlyzofaown in Fig. 4-2. Whatr5.1hyz1 o3qaap3 dl u tkxzf j/))n)u are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what-;q6 ytvsi3o:a)mmj a is the mass of the traffic ligqt;m: vysja 6mo i-a3)ht?

  Two boxes of masses m a0 4kow 4us2u.3hytxdqegt5s ag c6h0 .nd 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) Whuyae 0w3ch42hugs gx5sq 64otd. kt0.at is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with eachg y (syxql4c+2t-u5m03wmr cl other on a frictionless surface. (See Fig. 4-3.) What is tuw5(-t2y4mcl l0mr +qx3 gcsyhe net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) Ifj-oajl,ef q/k*- q r*l the forward force on the more massive box is F, what is -k- jlfleoq*r* ,q /ajthe tension in the connecting rope?

  Two boxes of masses m and 2m are connd*,xpsa)qj 0et)p soh (;.x grected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the accel )g(serjxx p, p)h;d0s*oaqt.eration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown iwti+jk1oph+3 n Fig. 4-5. Box I k13it+p+w jo hof 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 and k 2g/ +r2 k31h+jjkz 5t)mli heev*mokzinetic frictions between a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force o* rzmetol jvk kkz2i)+e3 hmj52h1+/gn the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinr n,e7o:1o 6k0ke gbh,y xy,v1b un4ametic frictions for plastic on wood are 0.50 and 0 m7 xn:yokve,ku4,on, 1r 6h0gab by1e.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 slows and comes t: 18uv+dr bd3 vgc7hr efe-j/ kqr*yw+o a stop with a consvu k7bj *+ /ee+:dh fdwv8-1r3gcrqyrtant 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 pulled by a 5.0- :wh3fkb i ss5(d*ftb4N force. A 3.0-N friction force retards the motion. What is the acceleration of the obhbi(d bf* w 3ksf4:ts5ject?

  A horizontal force of 5.0 N accelerates a 4.0-kdysbofnyk 3ad8pd0 +j79w wx;rc3r49g 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 slides 5d f4c47tx(mv ion i2*oy5bg*e 0 m on the ice before it stops. What is the coefficient of kinetic friction d(etcf2 oix*4nv4 ibmog y57* between the puck and the ice?

  During the investigation of a traffic accident, police findk 2ultk6*:j nx 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. Estimate the speed of the car when the brakes were aux nlt*6kj2 :kpplied.

  Two boxes of masses m and pe/5kv7q1w7.sp8 p8b ztgqfr 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 staticsr/ 18pqbf 7v.t ekpqw587gz p friction force on the less massive box?

  Two boxes of masses m and 3m aogs/0: uu3sy,spax 2tre 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 gy0/ota,spxu : u2ss3rough. 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 frictionleqrt o6 p0c rw:lb, hy6fzaj215jt.t1kss inclined plane. The plane is inclined at an angle of otrz1q1,6f. twy ah:5c2l6j0rpk bjt$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angle,x3g;uisg v 2fdbi8fs6s6(bb 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 witzj8zr; 4nnasg +( c(sgh 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 at an angle oh54b vm96xytp6 3f ,0kmswsouh1nr6nf $35^{\circ}$ 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 inc/*e.b ngb pl6btuz lu54jni. w7i6l j0lined plane, at a constant velocity of 6.0 m/6 4uljlbw7*/.jeizi.n b lpg0nb5 t6us.
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 sdn7*ne)l(r1ds4 mqu x lides 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 rok fgihv3 ;4y3k3 vnss*ugh $37^{\circ}$ 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 4s+*j :e4fo1rbown 2vjs)bgp N along a rough surface. The cable attached to the log makes an angle of:2bbr1es4)g4jo nvopwjs* +f $30.0^{\circ}$ 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 tilted at ade30kf- yrk(ln angle oe krdk y(fl3-0f $33.5^{\circ}$ 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 aia5em*npda3f p+f7 t4ngle 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 b4a3 7+mnpe pta5*iffdetween the object and the plane?