Which of Newton's laws best explains why motorists 6sn)ev;idm(l3 -ulqz5 ec )nhshould buckle-up?

  When you sit on a chair, the o jo/v(0 umk s(94e*czg tsxd.resultant force on you is

  In the absence of an external forcc bq::l 4p5+fh oonbzh/bq+z5e, a moving object will

  When the rocket engines on the starship NO-i,x68bru +rumnct l .+PAIN-NO-GAIN are suddenly turned off, while traveling in empty sp+icu+mbu r.tnr l,x86 ace, the starship will

  A rocket moves througd qczoclc(rzmt.g.wn3)4 0e 8h empty space in a straight line with constant speed. It is far from the gravitational effect of any st)gc.z3 ltqre8w0(.cz cd 4onmar 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 fot lst0 rd3;n/ m 0j92y+fkyzunrward, and you suddenly fall forward. You can imply from this that t rdnfn /+2tkj ul0t3zms90; yyhe bus's

  You are standing in a moving bus, facing forward, and you suddenly fall forwapbnib9x+sxz7/ p7bry jx// c:rd as the bus comes to an immediate s+7p/njxb y zcbpbxri/7:sx /9 top. What force caused you to fall forward?

  A constant net force acts on an object. Describe,ltccld3wv - hca10j/ ev02rb the motion of the object.

  The acceleration of an object is inversely proportionalpc7yd gr6hp;+ to

  A net force F accelerates a mass w-yeo;da dgs1x9;s8;1;hcxw fm,oho m with an acceleration a. If the same net force is applied to mass 2m, then the acceleration c d,so hw a-;8f x9oex gywm;h;d11so;will be

  A net force F acts on a mass m asw:j1q) kc )r.dq-hxpnd produces an acceleration a. What acceleration results if h w):1dx.k)r qqp-jsc a net force 2F acts on mass 4m?

  If you blow up a balloon, and then relhz t6a7 1bt pah0).bpbease it, the balloon will fly away. This is an illustrat) babbtat1php0.76hz ion of

  Two cars collide head-on. At every moment during the collision,l hd. .aoaaa9k u48/ui 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 first. This is anlo.k /8a ha9ui4uda. a example of

  If you exert a force F on an object, the force which the object exerl:v 1:h( ifpn zqlq 8n5j1r6v+ c)fdppts on you wilzh6lr5 nvpvj:(1lq qfpid8+c n :)1pfl

  Action-reaction forc/ s* v;11wjhi itu4nluko n4+des

  Action-reaction forces a l*o6++1vsmkdf1wl 4m su(9otwmq 9 ldre

  A 20-ton truck colli uvu5 cvo/- ,d0j4kzgu4gt:l fdes with a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is done on the5oj0uvgfdz k vu/ ,4ug4-:tl c car

  An object of mass m sits h )+3 g +/b5jxj:tlca bps9gjwon a flat table. The Earth pulls on this object with force mg, which we will call the action force. What ispjbh)l+c3g wjt 5/:+s 9xgajb the reaction force?

  A child's toy is suspended from the cew8 v318 0 7k jmhlfr -u;b2nj2ihqjqcgiling by means of a string. The Earth pulls downward on the toy with its weight force of 8kvj 3w1 rnflum-87jh0iqhb2j2g c q;8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you wirxi.i 1w 8w/f 4 z/onxqvo)(g.l) gudvth a 1500-N instantaneous force. The ball hits the bat with an instantaneous forcr)vqdl .wig(/1 n o fwzxu /v4xgi).8oe, whose magnitude is

State Newton's three lhfodqh +ovae2 t5a.b/3i+d1n aws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Whicla onu5l- 3h4bq)jof )h of the following is true about the mass and weight of an astronah3f -n)lqolao5)j 4u but on the Moon's surface, compared to Earth?

  An example of a force which0wqd- i4y)dmx acts at a distance is

  Who has a greater weight to mass ratikd(u1jm+;tbzs;: +e v5 msyqgo, a person weighing 400 N or a person weighing 6 ts5+gzk:ybu1v;+ds qj em(;m00 N?

  A stone is thrown straight up. At the top of itc2c7jhorl4ltix3g1pj 1) o + os path, the net force acting on it ispg3xc+7 1ot j)ol21iolh crj4

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the samedc:a pfb-c3 ei,*q4px height. Ignore air resistance. Compare x43 c,:-qci*pbpf aedtheir accelerations.

  A brick and a feather fkq3u 9vgp+n.1 .saylball to the earth at their respective terminal velocities. Which object experie +akvupl.1qsy.9g 3 bnnces the greater force of air friction?

  An object of mass m is hanging by a string from the cei8(, wy hfu;bguling of an elevator. The elevator is moving up at constant speed. What is the t (;8bu,ufwgyh ension in the string?

  An object of mass m is hanging by a string from the ceiling of an fquz9hi:2on vhg4 n6*elevator. The elevator is moving upward, but slowing down. What is the tension in the st:2q fnzo*uhh v6gni 49ring?

  The force that keeps you from sliding ocv5ikqf8 j7 9cr/ (b1g1rok dfn an icy sidewalk is

  It's more difficult to start moving cj*yy33j zuuy0 h2 z(wvps:u +a heavy carton from rest than it is to keep pushing y0(jshyu +w uy:23z3jvpzu * cit with constant velocity, because

  A horizontal force accelerates a box from rest across a horizo89q4 55xt ozmmzti. )hq1 gaoental surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same withozeqa4 51hqt8.)m t5xozi9mg the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slide*ll a5clq)yf4 s down an inclined ramp at constant velocity. Thus we can 4 *aqcl fl5y)ldeduce that

  A block of mass M slides down a frictionless pl7n 1bm7kktk w; 6wtg2lo;hh aci(dw8.ane inclined at an angle q with the ho2 wkimk7w w(og18bh ;d.c;lk7tn h t6arizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionlm m 4j-esqbx77ess plane inclined at an angle q with the horizontal. The normalqjm s4emb- x77 reaction force exerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane inclined atn1g1(sq )pq 7rpub v7y or3xx; an angle q with the horizontal. The gravitational force isvxr1x (p)p7u; 13r7oqqgnbsy directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously on anmuh*uqh5a n)e; y;ei- inclined plane that makes an angle of 30e ; hhy;)-eme* qiuu na5with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a bp )4d11wrjxhfrictionless surface. A 16-N force is applied to the object, and it accele rxpd1h1w)b4jrates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg caprq6 ay.axzop h6 +h/+n accelerate from rest to 27 m/s in 7.0 s. What is the average fapxhz +/ya rqo+6.6 hporward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 2ft o6p vz6yk0m/s in 2.0 s. What is the net force acting on t fktyvzo0266 phe body?

  An antitank weapon fires a 3.00-kg rocket which ac s5kxmv. .lf7jquires a speed of 50.0 m/s aft l.. xjkm57fvser 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 force that youyq,b:lnut u:, 2h7nsn:pmm9h push a 10-kg mass from rest,ynn:7,m,q :2luhpbnhs t :m u9

  What is the mass of a person9 bokt a65 4pc/yc:vzm6j0aauzmp(;c who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface o/9 -ay4 sppr9afv/7kt9 wrbkmf the Earth where the accelerap97mwvk 9rpa49//rb ak ts-y ftion due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the E+u;- a-lm /s0itkwzjn6qx1g g arth. What is the mass of the object on the surfacelwksx0 +quat/i 6nj-g-1;gz m 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 object B weighs 40n 1g2jxud0 x vhaib)++ N on the Moon. The Moon's gravity is one sixth ih )bxdj12+nv0gua +xof Earth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on owy7/ az24uyu ncfk85/l fiqb .a-lz; g nh/9fopposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates towaf hz9ul;n/g8 /nf7 -byziao.2k5ca fqw /u4ly rd Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface.8ra 9o10(olmov,bq .cs0xua aqarb+w o 1y g/- A force F acts on the stack, and it acceleratecu +vm9qo s8gabaa0,oxro -(ly10.ob1rwa q/s 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. What will the scabenkmdc- :rh97x( k ot3f *y8ple be reading when the elevator isdm ht: n-oerkc(7xf b8kpy39 * accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is 60.c.,g si1b kgf0w,q1 vym :fh-h0 kg and the el1gc,b i fq y0,.-w hhgs:mfv1kevator 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 elevator. If y8tc:tcn.z6 mh/wnj: the mass of the person is 60.0 kg and the elevator accelerates upward with an accelerati:t8/h.jn cwz nm6:t cyon of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kiypxobp)g), vuc235s g mass. One force has a magnitude of 8.0 N and is directed due north. The second forxpy)pi ubvo5 s c2,g3)ce 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. g(+*1ea 2gqkbkeslm*d0m.p tIt 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, w2kste d e0(q+a1 pmb .g*gmk*lhat 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.flo ;yx+3)s 8u l. bdvwo8(eym It is held in place o vd3w +y);ye8bm(8 ol.xfslu 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 load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = skw j2,.v:g/ itst.u h:7aca+ww to/q0.60 kg and m = 0.40 kg, what is the magnitude of the accelera/qug7shtvsakwawo. .t,:2 j/ wc t: +ition of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m ke2k)( 923npqtxd dqge a,02hy7w 7q b-dcrsd= 0.40 kg, what is the tension in the string? (Ignore friction angdadrns3p b ) -(kxq0 k27d,h29qedwcet 2y7q d the mass of the pulley.)

  A student pulls a box of boo4;p 55qn,p c b+sosb fmtp9nx(ks on a smooth horizontal floor with a force of 100 N in a direc nn+po55pcmb( b49st;qxpsf ,tion 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 withl;i y7asi ; dm8wdn5s. a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books iianis ;l m5;8 .swdy7ds 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N is supported by two rbcm.l1 4er dt0mre3)n9ce ) ntopes as shown in Fig. 4-2. What l9e te0cbd c m1)3e)4 tr.rnmnare the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass1,thsv ( (aqzwily/ v69 ad nz7n*zz0t of the traffic lightd (7 w/lna (vt*zzv,9snqyht z60 1azi?

  Two boxes of masses m and 2m are in contact with each other on a frictir ;2 6sdqjr7vbonless surfarr7;2v6 b dqjsce. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each o, 4chy m8qlo; wjfx)0z.oapn-ther on a frictionless surfac 8f)o,qz4c. ljha xwo-y; mn0pe. (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.) If the fq98h-;w qgc yfgf-pr6 orward force on the more massive box is F, what is the tension in twh pf96-;q -ygrqcgf 8he connecting rope?

  Two boxes of masses m and 2m are connectejc kns3bajk/+ /.4vj ud by a rope. (See Fig. 4-4.) If the forward fkujj4c/ +saj v/k3 n.borce on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord runni3 j+hv:xt)kc hng over a pulley as shown in Fig. 4-5. Box I x+k3c)h hj:vt 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 3.eu2-m- sd4ts j0-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 foe-t- m4sujs 2drce is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.r: yq)fsbdf,550 and 0.40qr: d f)byf5s,,
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 s9 vmc3tjk6k : iz/ruu+lows and comes to a stop tukr9 iu zv +3cjk6m:/with a constant 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. rps ;y f, qk+0sshrm.(dp)giy8(y5ck0-N force. A 3.0-N friction force retards the motion. What is8+qs( khd0sp i5sp ),rmgfckr .(yyy; the acceleration of the object?

  A horizontal force of 5.0 N acce.lz5awedbhp.j2 kr*u;s,ts kk9qdut+ v*r . , lerates 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/fek 0 kusp*y99v.6d aos. It slides 50 m on the ice before it stops. What iskkes*ay fod96v.pu 90 the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, police findezwg ;a( ct8kwvv 7d51 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 speed of the car when t5zca1vdww vget7k 8;(he brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The(e1ee lq30kex h(-z.ah-qef1hxh-qe surface between the more massive box and the horizontal surface is smooth and the surface between the boxes is rough.z0-eeqhe h fq.xl1kx(a3-eq eh1-he ( 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 Fig. 4-6jsqs r9u;k:i0.) 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 tsj9uq k: i0s;rhe more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined2 r/o6aosv,7ql2st.hubb . qa at an angle ofuoo 2rbb vqs/,7a6al..th 2qs $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill that makeagrc) w+1d5ez1u l .aqs 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 angle izof;1oabh6/ew -chiih c 0g1,z ,eh/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 inclined1kr p8opv:wd, 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 inclij7+ ojz9y) x9ipl k (xpwib9(aned plane, at a constant velocity of 6.0 m/si j9xzbop7 xpj()9a9y+ w(i lk.
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 slideips3;uwc)vm 1 s 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 vzt,yi- mo6o2h $37^{\circ}$ 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 cabl,9n xydb6 wwon /coe4,ki 0tr,e attached to the log makes an anx,wyi,w4o cd096b /k not,erngle 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 aayg2hk.6/ si,f5 hu lrdl6f8v rough inclined plane tilted at an angley6hflk5,8f2sha6.gd irv /u l 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 an if g*yawsnbsw h+a:d :1a( v+.wnclined plane. The angle of incline is gradually increased until the object begins to slid: wa1 :y(av +hswnfs *dw+gab.e. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?