Which of Newton's laws be +;z9fejuac 7la)iw /fst explains why motorists should buckle-up?

  When you sit on a chair, the resultant force on you7o pv0pv 6: k su tqk2i8.z)lqscg6g3d is

  In the absence of an external force, a mer2yn8mw3 p ekm(zs/1oving object will

  When the rocket engines on theu+.kv/oo 6ool starship NO-PAIN-NO-GAIN are suddenly turned off, whil k.o/v 6+uooole traveling in empty space, the starship will

  A rocket moves through empty space in a straibe)w )b9etor1ght line with constant speed. It is ew1bo b 9ter))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 sustain its motion is

  You are standing in a moving bus, facing fo99t4 -i7erj8m etx/y owk0h sirward, and you suddenly fall forward. kt8w 90e7 smj-y4i eh otirx/9 You can imply from this that the bus's

  You are standing in a moving bus, facing forwad r of8m74r-ss. oozc)rd, and you suddenly fall forward as the bus comes to an immediate stop. W-cr.ds mz)sr 478oo ofhat force caused you to fall forward?

  A constant net force acts on an1q*k qp ghzxibd0q9 (tuc;7l. object. Describe the motion of the object.

  The acceleration of an object is inversely proportionyxlr + -ux*1kvp3 et0w(dxeu :(s(fgmal to

  A net force F accelerates a mass m with an acceleration a. If the same net forc6+zvh0 tqi: : dwimvd3e is applied to mass 2m, then the acceleratiohivv +mw30dd: : q6zitn will be

  A net force F acts on a mass m and produces an acw6knyn vkm. +i0g4+f3k 9ocwmceleration a. What acceleration results if a net force 2F acts onwgc3kyf6 +mm9 n vk.oniw+40k mass 4m?

  If you blow up a balloon, and then release it, the balloon wil68tx:qdgq*m(p c(zyy 9 x8obmi np:k7l fly away. This is an illustratiokyp9z:m88icxy* (qpg :7q(mbxto nd6 n of

  Two cars collide head-on. At every moment during the collision, the maigh+z *lr)9+nwj cf; jgnitude of the force the first car exerts on the second is exactly equal to the magnitude of+lcij+ 9; rfjh*nzwg) the force the second car exerts on the first. This is an example of

  If you exert a force F on an object, the ft0-w4bn fafzu7ihg4p4e a- y:orce which the object exerts on you wilayz7h04bgfip4w- t -f4:eu an l

  Action-reaction force . vjvmcxau j4djb8:( k3fu.bm:wj(l4s

  Action-reaction forces ar.aojhqg::zv/ b c:s,ge

  A 20-ton truck collides wi rh8m49dwxif42npf1 ith a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on the car48 9dfpix1wmni r4f2 h

  An object of mass m sits on a flat table. The Earth pulls on ty : lw2gj4,ixbe f.v7mu;8 mmqhis object with force mg, which we will call the action mb.2y;g xiufm7l:qvm e 84,jwforce. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Eanmk*v8p-0z vry0,a ube 1a+kyrth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction-k*eu vk,bmva +8n0a0y 1ypz r force"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. Thdr7-j ga/oo ;ae ball hits the bat with an instantaneous force, whose magnituga- 7oj d/aro;de is

State Newton's three lah7:38nags- q xan1wpahdqy /2 ws.

  Mass and weight

  The acceleration due to gravibzzlkd,mh+kerb j/v0 l9h8*9 ty is lower on the Moon than on Earth. Which of the follok* 0h ml/ b9lz8kbrz9hjd,e+vwing 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 disjjsp2p9itn,.*q(ht5 qu :79z vjtk zztance is

  Who has a greater weigh ,edqw;qz af-3t to mass ratio, a person weighing 400 N or a person weighing 600 N?a-3w,zqde ;q f

  A stone is thrown straight up. At the top of its pa8gs8ro +z)u mpth, the net force acting on it i8uz)s m8+rgop s

  A 20-N weight and a 5.0-N weigq6b hk23uy9 to73bwnmsmx6y. ht are dropped simultaneously from the same height. Ignore air.mo 9 b3wn7kmq sb236xyyhut6 resistance. Compare their accelerations.

  A brick and a feather fall 8. t52;/v1vb um fl+sjy ozceo0v6 adgto the earth at their respective terminal velocities. Which object experiences thezya 2vl/0 e; f c68.tv+omj5gob su1dv greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevator. Theuuw s0neuftqy0;*7 rt6.uo7 a elevator is movu et6t7arn0 us 0u7fy*;.uwqoing up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string fe* cumi 4:-w. n0ou)hhjirb8 from the ceiling of an elevator. The elevator is moving upwar h iiuuhe : c*4owfn-.m8b0j)rd, but slowing down. What is the tension in the string?

  The force that keeps yjw4)c tmej5v2 ou from sliding on an icy sidewalk is

  It's more difficult to start movi p (d3s2pf7ov5*rrjpong a heavy carton from rest than it is to keep pushing it witppp3o52 fsod(r7jr *vh constant velocity, because

  A horizontal force accelerates a box from rest acrosdz8hdq udv4t3+ j xq(;s 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.uq h4t+dz8xddvq ( 3j; What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocity. Thus w78lqhn /eg w/btt*d kw42a e+we can deduce thaw4+ awt*w n7lbdq//gh8e tek2t

  A block of mass M slides down a frica/yq0k+ cd3w jtionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane o +j a03kwd/yqcn the block is

  A block of mass M slides down a frictionless t2bo-7my6d fi:,v e nsplane inclined at an angle q with the horizontal. The normal reaction force ed-nos2 ,:tvmf 7eb6yi xerted by the plane on the block is directed

  A block of mass M slides down a frtp k 3c (x92a7v9dm pfj6xt5ojictionless plane inclined at an angle q with the horizontal. The gravitatx tjdcoa5vf(6pt 3m279 pk9x jional force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on3 p d8y6rkvdqiz4e+bw;-s i)d an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration afteddzs4d6 i)kip -vr e3qyb;+ w8r being released.

  An object sits on a frictionless surface. A 16-N fkwwhxk.*jc 5(,oi : mhorce is applied to the object, and it acckchw*j: mox5(. ,ikhw elerates 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 7.0 s. W z5qk72jf xy.lr f5r.g:efkw 0hat is the average forward for qfyw fr2j:05e f.lk.7 krz5xgce on the car?

  Starting from rest, a 4.0-kg body reachesq3 vdqmk w)3bdf,yj ;2 a speed of 8.0 m/s in 2.0 s. What is the net for 2bqqd3v3wjyf km),d ;ce acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50. dkv1kksj+b 500 m/s after trave015vkk+k jbsd 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 force tampkt z*x,3i0hat you push a 10-kg mass from resttimz*,xa0k p 3,

  What is the mass of a person who weighs 110 dd rcz.4*5ko rlb?

  What is the mass of an object that weighs 250 N on2*giom,45 apbe2br-a,qbukap7 - jdo the surface of the Earth where the acceleration du,am-7 2j d bbe4agbq,o*okup5iap-2r e to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is the mass of the object on h 9wnvo( 4k yzoizcf *2a*v(-*p:xykg the surfaok*y(gz:k4 w -ypi9czv a xv*n2*( ohfce of 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 e**y(sy ,:k u ywcd8teobject B weighs 40 N on the Moon. The Moon's gravit*c8(ys kwy: yde*ut,e y is one sixth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of*its(xdcahv dty47 1 (-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Set st1c7d(vh(d*a4xyian's force if the rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. 2;e1n+ i necchA force F acts on the stack,en;c+1h 2cine 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 elevator.edvyzd(wusm *6 dx/(x d0v2h + What will the scale be reading when the elevator is vhv( umddwd*0ed+2s6xx /(zyaccelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the persz +ijv . r5stzg,z:4g;kdv)pp on is 60.0 kg and the elevator accelerates doti5:g4 )pv,+; kdj .zzsprg vzwnward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in 3mpghb. i lod7 5wyf))an elevator. If the mass of the person is 60.0 kg and the elevator acc)lg pdiyh .mb7f)53 woelerates 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 magnitk3as 56 vl;-dn7ka ;ylld ;jnyo,,jqbude of 8.0 N and is directed due north. The second force toward the east has a magnia7jnqbv6; l3,od s;k k -ayl;ldnyj5, tude 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 held inkwkrbq9) p4b8 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 distb kq9bk4w pr)8ance if the load is not to slide forward into the cab?

  An object of mass 6000 kg reib95l vfc4aan+ o0 m3vsts 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 tam9lo5v3f0 n4vac+ ibruck 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 = jw0q nae 68:il0.60 kg and m = 0.40 kg, what is the magnitude of the accelera:n 68i qjawe0ltion of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shokk+k b ne35j3twn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and the mass of the pulley.)jn 3kb ke35+kt

  A student pulls a box of books on a smooth horiv85 e 5qc0 fm8kp-y)cwsnz9i jzontal floor with a force of 100 N in a direcc 8mwk 0n95vi8f z)p seqyj-5ction 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 smocg cxv,t4e45c7xx9 qjcj( g d7oth horizontal floor with a force of 100 N in xx(cxdg c5g ,ejcctv474q 9j7 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 iigi,w0m ld.v-m.cd9 se8 fj,h s supported by two ropes as shown in Fig. 4-2. What are the tensions in the r0djlg d,9i m v8.w,c-.mehfisopes?

  In Fig. 4-2, if the tensions in the ropes are o.6496ynd2t mcw-8a; chyxol. tpx xl50 N, what is the mass of the trafficl4 8 xcctaon-;dxlmw9xyyot.h6.62 p light?

  Two boxes of masses m and 2m are in contact with each other on a frictionle:4 cy8k v1fupvtwan 1sdx(7;iss surface. (See Fig pd 71:c8y;kvwv(f4 xiuants1. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m aadr/:a )w 2ea29nmuxi,8vlluge *lw/ nd 2m are in contact with each other on a frictionless surl),aw awi ax/28r9 u*2/vgm enldl:e uface. (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected ), 2g9nc-+f peu o,bkdaewicu tvc -;7by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension 9cdeic7naf2 ut)buk,g ;ow , c-vpe +-in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.)5akeohr: f 6gq /i:wcij3e)e7 If the forward force on the more massive box is F, what is the accelerigei:6 / w375ohkra:)cjq feeation of the less massive box?

Two boxes are connected by a cord running over a pulley as slf(i19mpsn,,7 t bzfihown in Fig. 4-5. Box I1 9 (,ftbi,mpzf7ilsn 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 betweerhkpk a6; gq1m)a 3mnjdl(0 *zo r-a;vn a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is the net1 a)gp 0kjkalnr-mvzr(qo;am6* h3;d force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plasti (n 53mdv1wsfrc on wood are 0.50 and 0.4rw1(5 dn 3svmf0,
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 tocis v./xxi oxf6y1;ex+yst/7 a stop with a constant acceleration of -;etsiix176sx+yx o fxvcy/ /.$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surface isq*wd0zr;:bxr aq4a ew 3hdm; 9 pulled by a 5.0-N force. A 3.0-N friction force retards tr3 maz da0*xb4wrh9:d;wq e ;qhe motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest,t v70;jlkrv ,m 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 slide6sw 2uv tyfm4)1k- eyds 50 m on the ice before it stops. What is the coefficient of kinetic friction bems6w ufkv4yd eyt21-) tween the puck and the ice?

  During the investigation of a traffic accident, pmbzt;(nsfn6n:; z xigmy-p/ x747sayolice find skid marks 90.0 m long. They determine the coefficient of friction b47 b( i7gty /sn;szz6apn nx-x:mmyf;etween 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 applied.

  Two boxes of masses m and 3mopd5c- z8-s0/i qi rwrlyl f,a6ft73*ineiy 5 are stacked. (See Fig. 4-6.) The surface between the more massive box and the hori 83w/n eat fyziidqp ,f -*islory0556-lic7rzontal 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 stacmo pfund+44bv -)v)qo ked. (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 thqn 4 4)+obmpuodvvf -)e more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless incl m)mvxdgv:it;w, t,i wk)-m /bined plane. The plane is inclined at an anglemi,bdwt ti)m /-;k ,m)xvw v:g of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes af 2 zvx4*nyj-in 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)lh ),fva: kuy 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 smooth inclined planej5 a8:aev gwz((8i cz:kb*mbg 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 n dyvf/ *)mf55iq f4lyplane, at a constant velocity of 6.0 m/5fny)qvi4d*my5l ff /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 sli-prj/(khwh(1q3s 5 qjr adg a2des 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 roug(,u:k l+:/t scgfpe + ;uyvjfaz 9y8hnh $37^{\circ}$ 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 surfacetu.z vy; jbqq. lun22;. The cable attached to the log makes an anglv.zt2uj;n 2yq. b;qlu e 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 (n)lw:1g 7gjy5wemvfo 8 qrl2on a rough inclined plane tilted at an angle of g5)r8gvwon eqj7( ml:2yw1lf $33.5^{\circ}$ 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 of incline is grapi)u(6;n j pn9uupd vz+5tnkzq+/ v4vdually increased until the object begins to slide. The p(qn;/i6+z j4uv5v9dn kvz n+) t ppuuangle at which this occurs is q. What is the coefficient of static friction between the object and the plane?