Which of Newton's laws best explains w4ajzb+p( s4lo a1-ujv hy motorists should buckle-up?

  When you sit on a chair, the resultant forpy9a9u,znog+ ce on you is

  In the absence of an external force,)qpf 4 (,i wyygls7r8u a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN aregw 8aj/a43*fvs ys/ mt suddenly turned off, while traveling in empty space, the starss aa4 /vft8*jw/ys 3mghip will

  A rocket moves through empty space in a +f,wp)st-t0 fh 5oa)v xj /gahstraight line with constant speed. It is far from the gravitational effect of any star or p- xg whj0)h5ovfp t+)tf asa/,lanet. 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 for zw5)x(vrc+ imward, and you suddenly fall forward. You can imply from this that thxz5 +ri) (mcvwe bus's

  You are standing in a moving bus, facing forward, and you svaep1 srf.h f3.m v2u9uddenly fall forward as the bus comes he9vaf1mu3.vr.p fs 2 to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the yx8 :ho04jh; az:f y yrqhik)7motion of the object.

  The acceleration of an object is inve ;bpbv*w+ac(tyq 8jzxo)39l i rsely proportional to

  A net force F acceleratesn,mn6c )s.g vjggmudt,*+w loln96g 2 a mass m with an acceleration a. If the same net force is applie.n+d,l cg mswg lng6v9nu26om*,jg t)d to mass 2m, then the acceleration will be

  A net force F acts on a3 b c);hby.loe m*i625knav qj mass m and produces an acceleration a. What acceleration2bl ;*ah nb3eoyv5q6j i).km c results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, th-+vu va0 hp*ohe balloon will fly away. This is an illustration-p havuh+0 o*v of

  Two cars collide head-on. At every molznlz+o*o olr. i;p+byul:35 ment 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 3y zr;lo p*bo in:5lll +oz+u.first. This is an example of

  If you exert a force F on an object, .2e7+imp+l 2ew uzo zithe force which the object exerts on you willei p2mw+ l+ u7oei2z.z

  Action-reaction forchu4x9 : udfqb 9w syw:n14rl7fo1qla 0es

  Action-reaction forces x (,mwt fg qyv73,ll/ware

  A 20-ton truck collides with a 1500-lb caib 9okk o5lmm./ /pg6hr and causes a lot of damage to the car. Since a lot of lhm. 9p 56go b/mok/kidamage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this objfot*zw-4o 3 hkect with force mg, which we will call the action ho3k t -o4z*wfforce. What is the reaction force?

  A child's toy is suspended from theu3hp -6zy-tje ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is thtye3z-p uhj 6-e "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneo s;x2tgvqfem(fn(ivhg* ,13y us force. The ball hits the batf*3v(1(yigs vtmhg2 e;qx,nf with an instantaneous force, whose magnitude is

State Newton's three law8 lemi 3dkn405d o3iam(jz *gus.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Eak/mdpr2g7wa m*l) c bt 6ne17hrth. Which of the following is true about thelm 1bdrm7t2ac76ew n )p/h*kg mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a diskl: fo1pktwqrt-z/+4j i-j,fjde:8i tance is

  Who has a greater weight to mass rati85wvw 9umym.po, a person weighing 400 N or a person weighing 609v8m 5mywp.w u0 N?

  A stone is thrown straight up. At the top of its pmis3: pi ;qyec2m17d0hbcbg0ath, the net force acting on ygi:c ;de0m20 1 hc3q misbbp7it is

  A 20-N weight and a 5.0-N weight are drr7g:m u73v 1/gemxccx opped simultaneously from the same height. Ignore air resistance. x um 3/g x:c7cr1mgv7e Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal ++ g*o7mp *1fmhonfauvwqm:,velocities. Which object experi v * 7+gmmwfq1nf,h:aoo+p*muences the greater force of air friction?

  An object of mass m jy-kig3033q2ly( uwuj k4jul is hanging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is thul 3l- iy2(u3 q4wyg30jkkjj ue tension in the string?

  An object of mass m is hanging by a string from the ceiling of )iy2fg/aq / ,d3 txynes11 re+zkle6ian elevator. Thez)d 1q er/ gtki3sf y1x2e+n,la/ey6i elevator is moving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy sidewalk isxfhapl;2. . af

  It's more difficult to start moving a heavy carton from rest than it is to km z6 r)ox5 ui(i /pn3egpb7.aheep pushing it with constant vel u(igpm. 7he 5irxpzbon 6/3)aocity, because

  A horizontal force accelerates a box from rest ,.j4zlqib rt1across a horizontal surface (friction 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 happens to rb14jil t, .qzthe box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus we cg qs9(m-,z8wozo5 +f+lyv gpjan dez -5p9z( og,+8fojswqy+lvmg duce that

  A block of mass M slidkyb* +y3l*j 1-(xfla+ i skumpes down a frictionless plane inclined at an angle q with the horizontal. The normal reaction foy-u3alm fbl( *ki1j*y p+kx+srce exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q w+r/g1 iakk x lx)a+ty7ith the horizontal. The normal reaction force exertk x+ rxia1 )7gky/l+ated by the plane on the block is directed

  A block of mass M slides down a frictionp:iz; iey0 g-pless plane inclined at an angle q with the horizontalpi0:zi;e-py g . The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are e4ow8p* 8bwe*phssn6 released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which besto8w8hpe**p 6bws4 e ns describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force)*/ vxfhq;m shqlw5a5 is applied to the object, and it acce l5/*s5 vmh fhawqq;)xlerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass5 9:1ag j3tyzy cy3qbg 1000 kg can accelerate from rest to 27 m/s in 7.0 s. What is the average forward forcq: y31gyjzbgat3y5 c9 e on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.vhzp. q gm815c0 s. What is the net force actin8.c1pgmh5z v qg on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a sptorv 7+e3)ru n/ un1ipeed of 50.0 m/s after traven)nv/ u1i e3 upro7t+rling
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 sampp*nc ;2rh va6e force that you push a 10-kg mass from rernv2p6p ; hc*ast,

  What is the mass of a p;xvvocfds jom.fz- .e;)y l- 0erson who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Eart u yh3z,bdxkyd91iceq ( ab+8+h where the acceleration due z1k9uy+ qceh+ y dd(xib, 8ba3to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. Ww,ye;24tdw1j cas1 dbhat is the mass of the object on the surface of the Mowy1s ,b w1 tade2c4j;don 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 the Moon. The Moo54c8lmg+yf v tn's gravity is one sixth of Earth's. Compare the masses of 5l8tgv my4 cf+the objects.

  Sue and Sean are having a tug-of-war by pulling on o(2caoy53zys :n 1kqyv*d8g lk epp5e6pposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerate5 gaqy6vsld5kn1epceo z2y3 *p :y(k8s toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A /eh ;2e pghym 873jracfir/o4force F acts on the stack,jei3p/of c7e;h/ahmgr 2 48yr and 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 h)58uup wj inn*g71 kvelevator. What will the scale be reading when the elevator is w i15 h)n8pu7 ngjvk*uaccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in aa lw0a u4.+ ,w tc)tyumt-8ckin elevator. If the mass of the person is 60.0 kg and the elevator accelerates downward with an accelerationt.uc aalk+m8 tt 0wi,c4-yu)w 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 peryx8v+m p s0m(vson is 60.0 kg and the elevat+x 0vyms(p v8mor 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 magnitude of 8.0 N w4/1pc2rjr we l d;pq;and is direq4cjp;rwe 2 ;pl/1drw cted due north. The second force toward the east 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. It is hel1a eowm .8tm 3bh9ds(xd in place by metal 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 fortd98a3b 1.hwxe smm(o ward into the cab?

  An object of mass 6000 kg re6rr vdm1dn 4 7wdjo fpv2j..jr.4:ntw sts on the flatbed 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, what p.vrmf4w nn1d .jj.v4t6rwr2 :d7 jd ois 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 = 0.40o6xepp:c6z2m )a/sa k kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of the pullpax :2zsk) 6m6cop/ae ey.)

  In the Atwood machine shoggqmwy(pz+ b a*g7x: -ry1re, wn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore-gq1: e7gz a xgryw,*pyr(bm+ friction and the mass of the pulley.)

  A student pulls a box of bookq1hla )1 bno:ub9wyd 0s on a smooth horizontal floor with a force of 100 Nu0wn9b a 1do :)qyhbl1 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 smoothb(gi1u*g yye ) horizontal floor with a force of 100 N in a directey*ui1 )yg gb(ion 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 t7 h6j+o1ppk()techfvs g(a 6 lwo ropes as shown in Fig. 4-2. What are the tensions in thekvt cehho1667p g+j (lfas)p( ropes?

  In Fig. 4-2, if the tensions in the- ris9x :/zl:dj6h 0dr8rlzbc ropes are 50 N, what is the mass of the traffic -zl0 6 b dr9ri:/ 8dxsrz:ljchlight?

  Two boxes of masses m and 2m are in contact with each other onul9sd; 3li 0pn a frictionless surface. (See Fig. 4-3.) What is the0s u3d9n i;lpl acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a f45h b q1kpgqhz9igt 6:rictionless surface. (See Fig. 4-3.) What is the net foh:5igtz1gq h6p9bqk4rce on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.)d5(tswb1 rl b9n0xboo2l0f 91t e hcs0 If the forward force on the more massnlds w9ol1tbfcxt0sheo2(b1 5 9r0b0ive 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.) Ifuppiwmeud+o/vo 1 0j o1c ;3a, the forward force on the more massive box is F, what is the acceleration of the less massive box/c+vwoojmu0od u,;i3 pe p 11a?

Two boxes are connected by a cord running over a pulley as shown in Figim xmb:aj;bk3 h0qn 1csl) 1h.. 4-5. Boxjbhqs ac m.ixm: n3hbl0k); 11 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 static and kinetic frictions between a 7t iv :9lmwx(hn35paaia/.gw 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net force on tgv iwp/a 79ilaxw:ht 53m (a.nhe box when a 15 N horizontal force is applied to the box?

  The coefficients of s3n,l ft1l i0*ku4 qb oaipi5s:tatic and kinetic frictions for plastic on wood are 0.50 and q 0iiun3lbfi *ka: ,o51tsp4l0.40,
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 to f *y s xec5a 4c9gy2iuq5o95(f8kfa e-r8mkiha stop with a constant asfu4igi8c 5caex k9qfh ko 8aym5-2rf y(95*ecceleration 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 for:qqkcj.s9qo4t/- 0t4pcjci oce. A 3.0-N friction force retards the motion. What is the accet cop kc i.j4t0cqj:o/qs49- qleration of the object?

  A horizontal force of 5.0 N acc unzlj vxif:uqt**5,2elerates 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 speed of 10 m/s.wpddzsps/ky.- /p 1g. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the zwp1/.- sgd/ps .k ydppuck and the ice?

  During the investigation of a traffic accident, pol1y+eg)byjre) ice 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 prevailing conditions. Estimate the s e r)jb)y+y1gepeed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface bet;-eo sp uheo- 9a ,(iv2ldj2jnween the more massive box and the h;u2,v (dj- l2nhjio o-p9a eseorizontal 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 mbvm59p-/i qzq and 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, whqi-qbp/9v mz5at is the coefficient of static friction between the boxes?

  An object is on a fricti8z0vu g)isgwv.z2rz g:8nhqw l-o3k3onless inclined plane. The plane is inclined at an angle o83gwn)3urv sg. - zq8i20:ogkwlh zzv f $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a fl6u-la;5o (pj kr)qxzf7ky oio d20i3jat 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 8oq0 fdbm, o;j3kg5agan 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 mh/) .ckuk6/. yof jw7pp8lp 4bvf- szof $35^{\circ}$ 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 inclined4ov*z)j- 5j r mumzh/4vt;kb u plane, at a constant velocity of 6.0 m/v-mzk54ou* ruz)j4bv;jm/ t hs.
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 roul r++gv3e -i5bouwvw(gh $37^{\circ}$ 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 apmrdl9egtn/(6.bby +/e 1 vh s 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 lo48lbb rn y7t)z)*jn tzg weighing 500 N along a rough surface. The cable attached to the log makes an angle zl)4jr)y*bt7t b8n z nof $30.0^{\circ}$ 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 tid pd-a 1(8x+r 4wegjublted at an angle of1u+ (j8er4p xag-wdbd $33.5^{\circ}$ 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 angle ofwbd6 (y qz-(uk incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefb-6 uqdw( zky(ficient of static friction between the object and the plane?