Which of Newton's laws be atq2hmls /lb tone6)dw0wl0l// 60el st explains why motorists should buckle-up?

  When you sit on a chair, the resultant force 4yn7 b0dqt;y-e,ogk q e/mwgn)/qj;x on you is

  In the absence of an external for51an p )*gyjttd/ bs.b/s vlz+ce, a moving object will

  When the rocket enginxq8 8p-ifqk26emd /z(pmk .xjes on the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, ti8x/pmm 6 pez2jdkq k.f-xq(8he starship will

  A rocket moves through empty space in a straight line with consta0yxl-5lxo9i m8*g mkcnt speed. It is far from the gravitatiom8 xixcy5k-ll go 9*0mnal effect of any star or planet. 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, fac-) fe g1n aft +l(7pfn1-0h0hawuisgging forward, and you suddenly fall forward. You can imply from af1)h 1wl effa snt0n70igh+pu- g-g(this that the bus's

  You are standing in a movinb8taoq ot7k. 9x4y:h2s n;g png bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. kqnxtotyp7:9n2h 4bg.;8oa s What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion oh,qnm7; fkax5 l yl8/af the object.

  The acceleration of an object is inversely prlks8 *.u;snci oportional to

  A net force F accelerates a mass m(velv y z1g,mhv):vu6 with an acceleration a. If the same net force is applied to mass 2m, then the acceleration w6,lvzy1() emv hv:vguill be

  A net force F acts on a mass m and produces an acceleration a. What acceleratij,m i*efxn+0dm f)dr 6 -x7wznon resmi -nj )mdx*0z7ferdfnw ,+x6ults if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the b* r 363xplpjqlalloon will fly away. This is 33llp6rxj *qpan illustration of

  Two cars collide head-on. At every moment during the co7y ryq+*/vfwmkvf mbk m0+19 rllision, the magnitude of the force the first car exerts on the second is exactly equal to the magnf*mqv kr m+9yfr+/ w0vm7kb1yitude of the force the second car exerts on the first. This is an example of

  If you exert a force F on an object, thewk p 1u0l6fp)q force which the object exerts on you wilq 1l f0kppuw6)l

  Action-reaction forcekw z sahbx,zc(7f5-mnjo ,u3)s

  Action-reaction forces 7onmrfn; i6k : qo.g4uare

  A 20-ton truck collides with a 1500-lb car and causes a lot oz9 bms j x(t,rgl5w;q5f damage to the car. Since a lot of damage is donel (gxrz,m5 b95 jstwq; on the car

  An object of mass m sits on a flat table. The Earth pulls on this oba l9s+wy lcllwwp,e 5)3-k ue6ject with force mg, which we will call the action force. What is teua+l w6ywlp elw59k,sc)3-lhe reaction force?

  A child's toy is suspended f5bgvoj5vk t 1-rom the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. Ifk55vgoj1- t vb this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N jik 8y 7jqedbs)+v0x +instantaneous force. The ball hits the bat with an inxqs+0)b 78i +dejjy vkstantaneous force, whose magnitude is

State Newton's three laws-b)mh x2 4om0m ak agkk0gu)/j.

  Mass and weight

  The acceleration due to gravity is lower on xj ixe:lc. 2es3ov9b 0the Moon than on Earth. Which of the fs c 9bxxv:o.3 02jleieollowing is true about the mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distancb2r q7:svj ,x6jt,emve is

  Who has a greater weight to mass ratio, a person weighing 400 N or 5q 6j7vbcff2e a person weighe6v7fb qcj5f2ing 600 N?

  A stone is thrown straight us+2u hx8lfze /p. At the top of its path, the net force acting on it ez f82xs+ l/huis

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the samt7p0 6 9jr6vszu.j eep qsar78e height. Ignore air resistance. Compare their acceleratioe7r6 6at8szuep7sv.9qjj pr 0 ns.

  A brick and a feather fall to the earth at their respective terminal velocities.)pe9ujvqbeke az5v.t),qh1x 2d;. 6 bt c*jju Whicbpt.6qzu)aeu*ejt x;vv2dh1 ,9bj )q .ec5 j kh object experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. Theht 17wbdp2w 5c elevator is moving up at constant speed. What is the bh wwc5td 721ptension in the string?

  An object of mass m is hanging by a stb/ghp2p0f8b bgvq.d4 ring from the ceiling of an elevator. The elevator is movingbp4.g0bvq2df g h/bp 8 upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidej 0 dum1xc3qqg7,yr ,lwalk is

  It's more difficult to start moving a heavy cacm5b94psq5p*n;7ef hxsniu 28i a zn5rton from rest than it is to keep pushingp5 fun ci754*i pn;s meahx82b5 z9qns it with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (fua/s-v dhcmp9n69 qw)fh m+u 5riction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happen auh m+96 5sfvphdunm-c9q /w)s to the box's acceleration?

  A packing crate slides down an inclined ramp at constan, *)nl r2 lqi)v9cxprnfre-v3t velocity. Thus we can deduce th- p))* nlqe9rfr,n xric vl32vat

  A block of mass M slides doat89 d3an5 tiown a frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on th5tt9in8d o 3aae block is

  A block of mass M slides down a frictionless plane - nynwzjx3 +mdmd6z f )/:bu0binclined at an angle q with the horizod+3xwzy/fz n- 0)b n jbumdm:6ntal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q wigi0*khveo .l*c h 4x4dth the horl4h koei d.gc**4x0hvizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultanexo,edvhq7kt: e - bn5*ously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceler*v eknq, x: oh5bedt7-ation after being released.

  An object sits on a frictionless surface. A 16-N force is applied to the object 7b64yigrsu) o, and ib6gi4ysu 7o) rt 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 in c1m (bx5 f.s9hqax9ha 7.0 s. What is the average forward force on the car?bca(h.s9x9q fx1 m ah5

  Starting from rest, a 4.0-kg body reaches a spe+vzuwgr.eq6-l tevkn (0)iv*ed of 8.0 m/s in 2.0 s. What is the net force acting on ezi 6gnerv.-(lw k0*u vq+ )vtthe body?

  An antitank weapon fires5mmjv )+hjhn80rj4m y a 3.00-kg rocket which acquires a speed of 50.0 m/s after travemr04+j85n jyh jm)hvm 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 fopz)*ks3r 6zxt 0 /x)ti grx,kprce that you push a 10-kg mass from rest) t,)kx* 3 px06rtxgpizsrkz/,

  What is the mass of a perso2em f mpvu5o4l:26ko rn who weighs 110 lb?

  What is the mass of an m/7) vki4jwmdobject that weighs 250 N on the surface of the Earth where the acceleration due to gravi)wdj imm/7k4 vty is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of9ne i50uwbs1c the object on the surface of the Moon where the acceleration due to gravity cseb01uni 95 wis only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 49vu8p l: vo7nscs.e 2j0 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of :uv l7v82 c.oe9jn pssthe objects.

  Sue and Sean are having a tug-of-war by pulling o -0,qabbagh 4ju :t6 s30jxvqun opposite ends of a 5.0-kg rop uxbq 4 uj s0b-ja:g,tqa03hv6e. Sue 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 surface. A force F acts on the n9o/y zlzij* ,stack, and it accelerates at *y 9oz/n jz,li$3.0 \; m/s^2$. 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 elevat kd9nj2*por r65:1f5j 5es0dvc wj awgor. What will the scale be reading when the elevator is accelerating k06r cep 5:1a9fd sjwr*vj2 nw5 gjod5downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the cx z/3*j5nd raperson is 60.0 kg and the elevato azn*djc5x3/r r 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 eay q33)nwuq/ xlevator. If the mass of the person is 60.0 kg and the elevator accelerates /)33ayxqquwn 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. On2d;be4)4mj 3 x r)j zvzgifxy-e 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 the mzey zj)ixg -x4rdj2v) b;3fm4ass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held *nlqbzgycw h0gq9:dhk5+ i5 ayi(4, kin place by metal bracke5iqga9ky: z4*kh0ycwdgqnh+ b(il , 5ts 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 oj3y -zy2a h uw0ve5a)lf 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 mly2uhwaz 0-eaj vy)53/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 = 0.4n-v*w v9 u, ful:t3xks0 kg, what is the magnitude of the acceleration of the system? (Ignore friction 3 kf*ns,vlt:9- wxuu vand the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m =,mvg, +df2 s*bko5po y 0.40 kg, what is the tension in the string? (Ignore friction anpsv *obfkm+5d gy,, 2od the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor witgq2mlpv , hh 0 m0vo)fnl,0ld2h a force of 100 Npqolhvf,m,d2)lhm0 l0v 02gn 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 7iuz0so p elxhu7-k.6 floor with a force of 100 N in hs0 pilux6k ue-o 77z.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 is supported by two ropes as shown in Fig. 4-2. )g(fuw4h6 9/wxvz gq t What are the tensions in the ropes?hugw6 z( g49)fq vtxw/

  In Fig. 4-2, if the tensions in the ropes art6 ztgq;ksw9--inh 3ke 50 N, what is the mass of the traffic w; 39ksh-6gntkqit-zlight?

  Two boxes of masses m and 2m are in contact with each other on a frictionw62vb(ws1u v0b )zna (pzjt8fless surface. (See Fitufsb)z0vw( j61(2wn va8z p bg. 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 60,0urdwiengg b 3h7mfrictionless surface. (See Fig. 4-3.) What is the net force on the more w n bih 3g0u0m7e,drg6massive box?

  Two boxes of masses m an *co 8nz3go5fh4plg+ xd 2m are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box i + 4fgx 5zho8nop*3clgs F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Figedzows3s ;6 u:. 4-4.) If the forwarwe;zds s3o6 u:d force on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by sybh/ /sy7 /p9mdo 5rv9.hf ;yy(fkita cord running over a pulley as shown in Fig. 4-5. Box I of mad;9h t5o9psmi./y kfyfyv/(y/s7bh r ss
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 fricti)pftwq5u x1g x: *6dutons 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 the box?1 fp dut*)65xgq:tuwx

  The coefficients of static and kinetic frictions for plastic on wood are 0.50 mk /u9 hszg2rt9ko369 bmr-uwan/b9h9ok- ru 32srgtkmz mw96ud 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 +x direction. It slows ank0wh :crdd /6ph 2ham;d comes to a stop with a constam6hh :dh/cr;pad 0wk2nt 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-N forcey (t- kt bfwzz* )l5j4bjf0xl4. A 3.0-N friction force retards the m4l tjxb0f*k4fzy(-5l)z jw bt otion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-. uvd-(fq rf u/3-/vwtibtmg(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 puckd4 wffo;0juq itmrvi:8md8 k z5 8a90i is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetiifum9dm :kqa;jz0r88 fvo 5i04dw8tic friction between the puck and the ice?

  During the investigation of a traffic accident, poliw+ jfa. /5iuv5bxts2wqf.*l t c0*uikce 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 prevai.qtfvu2ib.xa+5 t5 l/wk f*j0ci s*uw ling conditions. Estimate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. c4 x7e16ohzh d (See Fig. 4-6.) The surface between th14h xc6odehz 7e 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 friction force on the less massive box?

  Two boxes of masses m and 3m are s-ow8oykes ifl +u/7gg,o;ha ,tacked. (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 coef-/i7hgwkao ol of ,,e8uy+sg ;ficient of static friction between the boxes?

  An object is on a frictionless i1 zdxv+*jlttid 2ukey0 z i(;8nclined plane. The plane is inclined at an angle xi +kzid1et;2ul8j t0d z(vy*of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a fj 9gtbgls7fm2u 9f +;w2jmej2lat 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 kg8uo 0l1, aazyzoe+7dxwsc 6; wvu/8 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 sm4rf ro9/ix741 kxvr llooth inclined 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, c/+aedfb84dmv so l 4a1s 7xl6at a constant velocity of 6.0se4 ld/ c8lfoam7x+v14s6ad b 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 mass m slides down a rough 4la 5mdz0ejapn/s r/1 *dx2jr $37^{\circ}$ 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 ro+ (ir+4yhsly ough $37^{\circ}$ 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 lo+(jt-j 5n0)9cwi-q axls b xbxg weighing 500 N along a rough surface. The cable attached to the log makes an anglq c9w ax 5s-l )j+0b(x-tnxbjie 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 tilted ats 1 l74m43qs8mmhsb(d l;zv wa an angle7mwm8 dal ;ss31 hz4bq(s4v lm 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 aw8oieb0c :t1)pj9w bb.av9 uun inclined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. Wi b):ubvwb 8uc ewt990oj.ap1hat is the coefficient of static friction between the object and the plane?