Which of Newton's laws best explains why motorists should buckle-u v30ce lf4g)0aircb8 f,2hd gpp?

  When you sit on a chair, the resultant force:/ i:gznoj;kf on you is

  In the absence of an external force, a moving objepy( kjh7f *+w-wq(z b6.rn ephct will

  When the rocket engines on the starship NO30yraaixrg( g -q pq5sf,jtft sj 821;-PAIN-NO-GAIN are suddenly turned off, while traveling in empty j- sxf2rt ;qjsi1(y3rgqag, 058t a pfspace, the starship will

  A rocket moves through empty d0 )a2n au3kdhspace 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 sustain itshn adk) 32u0da motion is

  You are standing in a moving bus, facing forward, and you suddenl2/gk;feo u1z pew d9w-y fall forward. You can imply from this that the buse p;9eoz/wfuw2 -1g kd's

  You are standing in a moving bus, facing forward, and you suddenlfh+jg jdur2 -9x :l-sy4w 2hkfy fall forward as the bus comes to an immediate stop. What force caused you to fall f - g:9 jw-kyd 2h+lju2rfs4xhforward?

  A constant net force acts on an object. Describe the motion j 4kh(x5otp8wacj y9, of the object.

  The acceleration of an object is inversely 3-bydlkz(w bcl,54kt proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net 2w 8qwrx,-k3p0 cytfa g e8s+iforce is applied to mass 2m, th0 giyt8rk cw -ae3w2qf,s p8x+en the acceleration will be

  A net force F acts on a mass m and produces an accelera+r74rgbel yodko g / ,5o+t.dution a. What accelerationrgok,++d 5d.t7 lybogue4/or results if a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. Tr2v0cwa30wv3 g ls h1ohis is svc0l3wr 21w3v 0hog aan illustration of

  Two cars collide head-on.ax: hg,ec1..3pw -b -jwud(ldroh+7b :wdcr n At every moment during the collision, the magnitude of the force the first :3p-,-+d hwb1:xlc(bogewnr dw .jchdu a 7r.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 an object, the force which the object yy/yqqwqid9e 4s 6) wci o-0c*exerts on you wil)w6*w0i- 9 /cyq scoieydqyq4l

  Action-reaction forcy6m+ vt-y)ukt es

  Action-reaction forces am .5eq.,t rdv9 fa5zbmre

  A 20-ton truck collides with a 1500-lb car and causes a lofka( kgi zgk93w;wj j7-3bjd 6t of damage to the carg3z-k;jg7 jw ijkf(d9 6 akw3b. Since a lot of damage is done on the car

  An object of mass m sits on a flat table. 5a ;vemx t0hli* u/6q xcs;-da The Earth pulls on this object with force mg, which we will call the action force. What is the lv/ t5daqa* ; usimcx;hx6-0 ereaction force?

  A child's toy is suspended from the ceiling by mefu.p+zib;ww 3w-e ;dnans of a string. The Earth pulls downward on the toy wie .zw dwu;w; +bp-3nfith its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched tp*r h 8odgjj u:mxj012o you with a 1500-N instantaneous force. The ball hitd2:0oj81hr upm gj*x js the bat with an instantaneous force, whose magnitude is

State Newton's three lawowv37xgkhzsy6 y39d6 s.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which ofdlzy0)m :8hsduinz ,* the following is true about the mass and wn:,z )idhs*z uyl08dm eight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a068 +tbdcyo*rp.k fok distance is

  Who has a greater weight to mass ratio, a person weighingxbqgk; *wp.ntgp6 3xx ,u(n x2 400 N or a person weighing 6 ,uq(tn2nb 6x*3w.xg gkpx;p x00 N?

  A stone is thrown straight up. At the 3 d;hov-5f pgwtop of its path, the net force acting on it is;hvg5wopdf 3 -

  A 20-N weight and a 5.0-N weight are v3z + sc9xujv q:rya37dropped simultaneously from the same height. Ignorr qz7 3v 3+:9asvjcxyue air resistance. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal velociti w-;kzts8 ) om v,12qrmo4jiaves. Which object experiences the greater force of air friction?, aw2o k1rt)viv;zo8mq4-m sj

  An object of mass m i7cskd :i5m lkwb:zb +6s hanging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tensiow6zbsk b:7l5:dm+ kcin in the string?

  An object of mass m is hanging byaxsa a+7 cm9/lxz5ki- a string from the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tensi+7 9aisaa x/zckl-x5mon in the string?

  The force that keeps you from slido0i3/j a2ooeixxeu 7r/otmu fk/7+sf e8y f: 2ing on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than itnk*o.qdh/bm:jb/: lk+hmtq - is to keep pushing it dk b.-jmhh/q+/kt mb: *q: lnowith constant velocity, because

  A horizontal force accelerates a box from rest across a horizontae0o7:zj3n 6ntr k+udlsg9 mz;l surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal forc z6u3j0zdkl;eg+ 97nrm:s onte is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constan,c6cu 0 6ctczh jem.s-t velocity. Thus we can deduce thatstuzh0ej- .mcc6c6c,

  A block of mass M slides hts1 u0n,x1,r) u 6 qqkp. 1wnuv0ypzkdown a frictionless plane inclined at an angle q with the horizontal. The normal rer1) zn00 q ppt, hu.,kqk1y6suw1vunx action force exerted by the plane on the block is

  A block of mass M slides down a frictionlesu4le ym9 jgqd4/0 y+w0:h g;b6katagds plane inclined at an angle q with the horizontal. The normal reaction force exerted by dy; 0qamg abd0/4w:etylh6j94g+g ku the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angl (j3rrp,9m p vtez:gd*e q with the horizontal. The gravitational force is directe zr93m :dp(vg,jr*etpd

  Two toy cars (16 kg and 2.0 kg)v623,hldf dtg are released simultaneously on an inclined plane that makes 3v,h6tlfdg2d an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is appliejgax,m bzn 04e8 34jjed to the object, and it acjg zj43840neaex , jmbcelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acceler+yeqcq 9n-k+ cate from rest to 27 m/s in 7.0 s. What is the average forwqc+c q+ey9n-k ard force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.(:d1v9p4 vw w) drgzns0 m/s in 2.0 s. What is the net force acr zn9)d4wvws: g pd1(vting on the body?

  An antitank weapon fires a 3.00-kg rocket which acn498ue qm sw7vm)ez 4cquires a speed of 50.0 m/s after 7ve)w muqem44nz 9cs8 traveling
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 forc 18b7 yj juhe8 l brek2ksfp4,wja;8.ye that you push a 10-kg mass from res1 bj4sw8e ubaflpj 8rj82ykhkye7;.,t,

  What is the mass of a person who weighs 110dkxr -,:p o/ud lb?

  What is the mass of an object that wxuog/ x8um6.(ax aa4yspgq+. eighs 250 N on the surface of the Earth where the acceleration due pg6.m/ a(auqo.xa+ xsu x48ygto gravity is $9.80 \; m/s^2$?

  An object has a mass 3: *vfnumb8yqof 60 kg on the Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravitnfvybq :*m3u8y 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. (:x:girl)3 *w2v zdskr1dm4r zz sxv7The Moon's gravity is one sixz(iw:d s1 2 mg3vkx)rs4 zv:d lzr7*xrth of Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5.0-kg ro76+ nps; y zq:xlmgm9/5ik88 py djvye b:rv4ep+:p iv edjps8mnqky48mv:lb /;e z7y5 yx6 rg9e. 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 ojwnwg 9 mqxrb:bwtqv0 .2g4ez 4(nw(5 n a level frictionless surface. A force F acts on the stack, and it acce9t xr5mwn w04g(v(eq wz :qwg2b jbn4.lerates 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 elevatorbd7jsszd ( :7t. What will the scale be readingddz7t: b s7s(j 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 per eeq e3+,z d.qron7f8sson is 60.0 kg and the elevator accelerates downward with an reseq3ne8 .f+z qod,7acceleration 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 person is 6fcyc3sed,-6 g 0.0 kg and the elevator acc63e-cfs, y gdcelerates 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 wp b:r.p * 4fyii6zfo8N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is the acceleration of the maspiy.o86iwr f* f:4pzbs?

  An object of mass 6000 kg rests on the flatbed )b3 s 5xwltyiue4w /i:d:onhco ,(( qyof 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 is the minimum stopping distance if the load is not totl/iwenqo iu), (3d:( swc4y:xb 5hyo slide forward into the cab?

  An object of mass 6000 kg rests on the fzoqdxh61 +4h k(as( nplatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontalnq(ho spx6dk(1 +h za4 force of 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 2z4jfda.-kah 900l oc6zhbap shown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore frictio 4b.apajal90zfkc-d z 26ohh0n and the mass of the pulley.)

  In the Atwood machine shvhrvg d 2+um7it5 d3ui):sq 5uown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction asivd ui)372mu g5t ruh5q:d +vnd the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal fccs8q:ua+ b *kloor with a force of 100 N in a dirq b8+ uc*akc:section 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 ug)e xm-.phmn v+o)s 0on a smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. mhngvu.0x)spe )m-+ o 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 bs s7xb :xuypjevpd:(3+-e - koy two ropes as shown in Fig. 4-2. What aro-s -pbxde3vuy: xkp 7 es+(j:e the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of th; 2vjrbtyzl6 :e traffic light2zljv:6 ; rtby?

  Two boxes of masses m and 2m areh4bbhs*-9dqr*g z r3c in contact with each other on a frictionless surface. (See c-*hh4 *gr9brbszq3d Fig. 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 frictionless sum6d ep28 h;twtf,jl p9rface.t82 pf 6wlhe;pt9md,j (See Fig. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-4.) xo1y:is rz sy1lsey94i*0- dq If the forward force on the more massive box is F, what is the tension in t* 4-siy: doq s1xy1l0rsyzi e9he connecting rope?

  Two boxes of masses m and 2m ar+e w*m hb0 m/ bd7brifsit01*re connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, whr w1+0i /0*7s thbbmfdm* bireat is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pugn ybf6yb 5(ag+8 .hy-mepi z.lley as shown in Fig. 4-5. Box I of mab6. ga eyp-.8+(nm5ybygz hi fss
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 3.0-kg box and abqrjt:m e (-.t desk are 0.40 a -(j te:mqtbr.nd 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are, 0nh, 1i.ektuikm3n rn :a;ya 0.50 an utan;e h,.kim3r n0i,1ka:n yd 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 and comz0a3l9 n*1 xe9ggsuixows8n:6i)t ores to a stop with a constant acceleratio :ln6x an 0s3i9gero*wt9i z)xo sgu81n of -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting :ni0d3fq i9 dinanz j3r l,1j(on a horizontal surface is pulled by a 5.0-N force. A 3.0-N friction force retards the motion. What irj :if9dd,n nzi0n3a li( q3j1s the acceleration of the object?

  A horizontal force of 5e me6-b5,qyud r+y2 v:)lguwy .0 N accelerates 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-nswwe lko 4(ba91 p;y/s. It slides 50 m on the ice before it stops. What is the coefficient of9k1p;easobwy wnl( - 4 kinetic friction between the puck and the ice?

  During the investigation of a traffbuu7x6 sd;qe 3ic accident, police find skid marks 90.0 m long. They determine the coefficient of friction betweu 6 eq;bs7uxd3en 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 3m are stacked. (Sec;tir1vey:* j1ab0 b. cxzy2z e Fig. 4-6.) The surface between the more massive box and they;2y bx 1.b *jra0itev:1cc zz 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 stacked. (See Fi- 5vrulh2q4w9 ch,w mig. 4-6.) The surface between the more massive box and the ho mlhuwqh25 ci,-94vwrrizontal 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 frictionlesshxwen;( b ,k(i inclined plane. The plane is inclined at an angle of(inb exh w,(;k $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makes an angl ojb,zwxej 554fkz18ie 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 inclinl7; rr/wr7*shr,mfc *jkl9 f3jlpv7hed 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 smooth 1s6otc* 6xmb4qe6m kw 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, at a const)tee/.jyfuy2 b .a;u kant velocity of 6.0 yaf2 )j./;ke t .uebuym/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 hphds58)s v60.fo( ewh eoh4 vdown 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 slides4t- +)u-t;gwk vweo;uevqb0c 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 su+x pm(0y1hsv xrface. The cable attached to the lo1(xxhpys v+m0g makes an angle 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 tilteg+-w,(x6a 9osnz ; 7ctylyos++a nrwsp k *6wid at an angle of y+nzp+ag;r7c- 6nyok isw(s l w+s9,tax 6ow* $33.5^{\circ}$ 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 isa-ic dko9*-ig gradually increased until the object begins to slide. The 9gk-ii* o-acdangle at which this occurs is q. What is the coefficient of static friction between the object and the plane?