Which of Newton's laws best explains why motorist 7lfp xc0rn(elw r rpl(1-hcm154j;ves should buckle-up?

  When you sit on a chair, tl gznb*5 r5ri;he resultant force on you is

  In the absence of an external force, a moving object willc )e g(7; lla fel6s;2ft9mb)y+mg 4k)ozriy v

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned omt dn8apix-o+ vt02rtk6f 6s *ff, while traveling in empty space, the sta +sp*d8nai-r2xt k0m6 vf6totrship will

  A rocket moves through empty space in a straight line with consta4a2gm p h-ahax6j) kbi/q*2 uint speed. It is far from the gravitational kgj*2b u-axh iami)2p6 aq/h4effect 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 3bh /kmsh49nh moving bus, facing forward, and you suddenly fall forward. You can imply from this thnh/4mhh 39 kbsat the bus's

  You are standing in a moving bus, facing forwa)rn).uzi(7 tdv y igl8u vgw9)rd, and you suddenly fall forward as the bus comes to an immediate stop. Whai ))nuvg8ydz .)ti r97lwguv(t force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the ob*x roiwf+y p2n yv,*zrmx-46 rject.

  The acceleration of an object iszmwf,5h.5a w stw2b 2l inversely proportional to

  A net force F accelerates a ma w/9 4f9/;lwh(san .sf rndieess m with an acceleration a. If the same net force is applied f d.w;/s/wi9nfsn e( h49rleato mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What aciy3u7un e(0umceleration results if a net form 7(0uy in3ueuce 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly awayjj;m2a. h )zucmhl va4h/20sqyxo6 k9. This is an i 0o l)ya9.vmu qs hm/jchxjza 264hk2;llustration of

  Two cars collide head-on. At every moment during the collisz coiwyur(c w3n.-2 /tion, the magnitude of 2y(uzo. /trnw3w-cci 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 is an example of

  If you exert a force F on and. g4 5+zcvbjs object, the force which the object exerts on you wilbds v.cj4gz+ 5l

  Action-reaction forc 2o hp s:t(.-h(rtdhphes

  Action-reaction forces z0 7aj/xbcwek); ah1u are

  A 20-ton truck collides with a 1500-lb car and cau8vfx dul31r t/ses a lot of damage to the car. Since a lot of damage is done on the txf1u/vd3l8r car

  An object of mass m sits on a flat table. The Earth pulls on this objecvue8g ace c5:au2--yc .+k uv71jlpad t with force mg, which we will call the action force. What is thea ee 5kc1.8 c gducy-u2plav -7vaj:u+ reaction force?

  A child's toy is suspens11lyfl ;f;oi2: dxl qded from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "ac sllixlyod;1f12: ;qftion force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a ;t9sv/y v,fv w1500-N instantaneous force. The ball hits the bat with an instantaneous force, whv;vt 9fy/vws,ose magnitude is

State Newton's three laws1g:2 *0ypajw uwdjq+i.

  Mass and weight

  The acceleration due to gravity is lower on the Moon ,3ugjhh, 0ntd( /ttvepa u;.s than on Earth. Which of the following is true about thee;(nh3,/h tjut.t,dps 0 vuag mass and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distanc yg wys*qpd1.yev3b,uc1f9r s9d r)p.e is

  Who has a greater weight to mass rahoqk 3 x pcb*(93/by3*alwzzf tio, a person weighing 400 N or a person weighb3( 3owq/fbch3a xyk*9zp* z ling 600 N?

  A stone is thrown straight up. At theod83x qz h4xe7j-olmtua ))(b top of its path, the net force acting on ia o3- e(x jodq7m8zlux)th 4)bt is

  A 20-N weight and a 5.0-N weignn -c90uqh2pkq;vgs +6ko5co3 99zicz x9rixht are dropped simultaneously from the same height. Ignore air resistance. Compare their acceleratn9 o9v +c 6 qc2xzqgi-0i;5 xsck3ruh9 nzk9poions.

  A brick and a feather fall to wjrq*cug 4pgt:1oh *:;wbk f) the earth at their respective terminal velocities. Which object experiences the greg)fu g:4 ;rk w*cjt*owphb :1qater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elevats exml-u:2m .36 etfcior. The elevator is moving up at su6m2 xf:i.-ce e3tmlconstant speed. What is the tension in the string?

  An object of mass m is td t ,,)x uyidrbo)h9 qd;-rr+ b/qrz1hanging by a string from the ceiling of an elevator. The elevator is mtzo d/,;-ry+dx ,)drr b)h tq1u9 ibqroving upward, but slowing down. What is the tension in the string?

  The force that keeps you from sliding on an icy d*iq,jvb w(0ka2h rz; +s8pcekl1s5 f sidewalk is

  It's more difficult to start moving a heavy carton from rest than it is to cvt* r(cpaqy4. z,g*ykeep pushing it with consyy(rp*va,4c*c zq. tg tant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (fric vwfwge-fc7 .k.qze.8tpi +t6tion 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 the box's accelerationqw v6 et-fe.+w.8tz.k pcif7g?

  A packing crate slides down an inclined ramp at co(lm1f 5sp;d aunstant velocity. Thus we can deduc m;f(dlp 5aus1e that

  A block of mass M slides down a f;7cpg rvjx.a3 rictionless plane inclined at an angle q with the horizontal. Thev3c.jx r7agp; normal reaction force exerted by the plane on the block is

  A block of mass M slides down n. 6dhwof bv:hbv/8 /wa frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the wbfnw8ov : d/b .h6v/hblock is directed

  A block of mass M slides down a frictionl72bt: r .hga3wguw 8yprivr18ess plane inclined at an angle q with the hori 1w38g:wu8 tvhy2 .pri7rbrg azontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are releasen b:p*3a)t ncud simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being releaut) an 3nbp:c*sed.

  An object sits on a frictionless surface. A 16-N force is appliedkz nx ls;3)gc3 to the object, and it 3nxz klcs)3;g accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg ch4 a2s4 p2smkean accelerate from rest to 27 m/s in 7.0 s. What is the average forward hss44 k2ep2maforce on the car?

  Starting from rest, a 4.0-kg bo)x5x d.q os,,jioqs+uu ylk3/ dy reaches a speed of 8.0 m/s in 2.0 s. What is the kil/q,u oxosjud , )syq. x+35net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of*1l3ydn ;til y 50.0 m/s after travey ;tn ldi1y3*lling
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 that you push a 10-kg ma-wh hj*n* 7hi eoe5ct c(f 5m(a7ud/spfa)9vpss from rest,(fcwmja*t 5c)u9vaode(e i 7hh p sf*n ph7-/5

  What is the mass of a person who weighs 110 n4kp9f (k0ocslb?

  What is the mass of an object thadml.a5 c l)5dx0rmuh9. x)kni t weighs 250 N on the surface of the Earth where the acceleration dud90c dul.n)5.) mkri 5m xlxhae to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. s3muo 3 9d,olnkf96n4loh7wf What is the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 l,d fo93hf6on sl39 7mkwou4nof that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moon. cd+k/ in;vf:kor)ob.(hv 9z4 euw)yq The Moon's gravity is one sixth of Earth's. C:9q ov)dn(e u;h4+ rv/kwyfik o b.)czompare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on of* 8bo( /d9n 4(e: ex .y ggncuspiodq)xm2ha1pposite ends of a 5.0-kg rope. Sue pulls with a 15-N force.i* oags4pno1x9 (nd8ef(gbeyuhd/ mxc2 :q). 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 actsk:y25g).b uriumkc nsf ; /xf4 on the stack, and it accung5 kycxfr )u2b:km;4s./ifelerates 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 inw0;4ie/, c-s.l jjjf3qsqtop dr7 ko3 an elevator. What will the scale be readinjq 7dqs-kpof.l wsi /34,3rjt0 ;ocjeg when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 6/:b:o r)wr wbcfbkogf 0u-s72 0.0 kg and the elevator accbrwf us ko-ow:2bc0gr7 )/f: belerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale ri ip.: l9 n1l jcb3znfsjnjm2pd ky3;q+4jcx,-des in an elevator. If the mass of the person is 60.0 kg and the elevatz3nbc j c;d+94-my3:sl1p.,j q knpijlnjx2for accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces ao1gc,f3x :et 0 nk;udvct on a 5.0-kg mass. One force has a magnitude of 8.0 N and is direcntfuvox3 kcde1:;0g, ted 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 held in places5vo 7ye.cb aq;0o ,k25kbcs p by cs pyskoaqb.v2, ;c7o05e5k b 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 forward into the cab?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in pl v * rl:p0 g0t;l3x:-sccmd/nzmfn0ylace 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 time if the l:f/y pglc 0tnmclzsdvm0* n:x0r;3-load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = h,qm4sie z 114rph*b t0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Im bhqi 4s*t4r1z,ep 1hgnore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m aouj53d0 z7lv = 0.40 kg, what is the tension in the string? (Ignore friction and the mozau 3v5d0jl 7ass of the pulley.)

  A student pulls a box of books on a sd 5cl qsei -uh1c/n(+smooth horizontal floor with a force of 100 N inics5/u1+q( h -s encdl 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 floor with a force 5o39bg,jmv:h/ cy 9rtnh+ 2cou zom:oof 100 N in a direction of 37.0e above the horizontal. If the mass of the box and tcy5c j2::, +z3o9 9hr mhto/gmuvonbo he books is 40.0 kg, what is the normal force on the box?

  A traffic light of wei(i7m 79ujz6yvd f9bi wght 100 N is supported by two ropes as shown in Fig. 4-2. What are the tensionsu9 j9wv i7(bzyd7ifm6 in the ropes?

  In Fig. 4-2, if the )f/unlno k6k:dg*bx 3tensions in the ropes are 50 N, what is the mass of the traffic lightf xn/k3g *o n)u:dlkb6?

  Two boxes of masses m and 2m are in contact with each other on a frictionlesha (b:/ v 5mo*xvzr0/ +tbfjture/*dos surfacevdfz m+ v( b*b/h0xar/* jou5etto:/r. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in p 1: xaq(/xpawnpoc2oq)fz20contact with each other on a frictionless surface. (See Fig. 4-3.) What is the net force 2wonxocf)a :z (p1a/ 2 q0ppxqon the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) 91h4yp l97 kyqi t e6rqggd:0pf+5 yfmtuby;4 If the forward force on the more massive box is F, what is the tension in the connecting rou+4gi0kyt7gy dm l tqrb9 :4qep59fp;y 1f y6hpe?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) If the fmfi4bd4y. kd6rz5 6j8ah4 b ajorward force on the more massive box is F, what is the accelerationiydda6 fj4zhj85mb4 rb6. a4k of the less massive box?

Two boxes are connected by a cord ( oqqpa)cnm34.g t0re (maexf7fv3 6k running over a pulley as shown in Fig. 4-5. Box m. re)cq 4gxmn a( 7eqf36pfvo30a(tkI 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 betweenway9v5ixqe3, 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 appix3 yvw5a9e, qlied to the box?

  The coefficients of sta,(equjs y-j;;6jfj2isi:usb 59 kikftic and kinetic frictions for plastic on wood are 0.50 anyuks(6 jiu;kqf:ji9f2; 5b,sje i s-jd 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 )u4a8m i s,ss +stt ycyl72oe*direction. It slows and comes to a stop with a constant accelerati2u*y tsteia )c,7oss4 ymsl +8on 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 f1e(dy6frfsm5qnz6m (+s+ v qi)v 1q bhorce. A 3.0-N friction force retards tqbvved+m zq6(nr)h sfs1 56ym1qf (i+he motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg massm /j+pjyj;q +kd nkeab82un/* , 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 aqf/n:3)5 0yrv wnx zibn initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and t50 n):vz yibf/ 3qxwnrhe ice?

  During the investigation of a trauyn(h6p3:vkyddjud( 7 4 dc5jffic accident, police find skid marks 90.0 m long. They determine t c 65yjdujddu(n y3kpd4 7h(v:he 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 applied.

  Two boxes of masses m a q/2 xkk2fq-p*a 3xbuqnd 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 static friction force on the less massive bo32k2 bqaqq-kx/fp* xux?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betw(o rcyc2zqa +*1 kply 6ulh+w9een the more massive box and the2z1lyr6 cuwpy +o ah(c* qk+l9 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 friction between the boxes?

  An object is on a frictionless inclineyq;fud9)/le1r(t (ndm 2oaa ld plane. The plane is inclined at an angle ofa f /rl)y(m1 utd29delq(aon; $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down49z k/zr9pm fh+6cnxn a flat 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 an ae3uffdbn 4g( gujrx1l06(.e kngle 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 ang7f/zxb rl.q c/,e,xs0k r(ots(h o5 bale 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 d slw9d1vsib47r/*z reown an inclined plane, at a constant velocity of 7dvi *9ber/zwr41 sls6.0 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 roupz4 jc:;mz5(vdt zbw,2k7z yvgh $37^{\circ}$ inclined plane where the coefficient of kinetic friction is 0.20. What is the acceleration of the object?

  An object with a mass ,ch bd;77 ;;vh.gpe 9kej3cmeggtbb7 m slides down a 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 log weighing 500 N along a rough surface. The cable kp(+-5 oau/eh cuht x1ikuh.z0,*eueattached to the log makes an ang e5ope a hu/k . u10,+-uuh*h(cixetkzle 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 inclinez ulngc.r 54b m-se5z7d plane tilted at an angle of .e-g 5c4zz5ru bns7ml$33.5^{\circ}$ 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 6uga4h5 6ett won an inclined plane. The angle of incline is gradually increased until the object begins a 4ut6tg6e w5hto slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?