Which of Newton's laws best explains why motorists sho8d7r*fakomz q)jsxa, i29 n8iuld buckle-up?

  When you sit on a chair, t+btfw ,y r(d8xhe resultant force on you is

  In the absence of an ex pxk 27)dtzn9ln24w lg(m+hgnternal force, a moving object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turnl/q 0 .vud-bb ft9(caled off, while traveling in empty space, t .vubb9dl(cq-lf 0 /athe starship will

  A rocket moves through empty space in a straight line with constant sp+qiv-f laa 7*deed. It is far from the gravitational effect of any star or pllf+7a*qv-i adanet. 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 )x3j6bhnvu824 kz s ffbus, facing forward, and you suddenly fall forward.s8 3x 4f 6v2hnkzbj)fu You can imply from this that the bus's

  You are standing in a moving bus, facing forward,xf8m-,rgq8moo9(3y w6z0 v w vvw2 itp and you suddenly fall forward as the bus comes g62 w0mp,rqo3y( 8tv8zvv9x- woif mw to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an o.7 -1cb cu /2-3y0pnwjovum qx-vzrpsbject. Describe the motion of the object.

  The acceleration of an object is inversely proportional too5u,:vlr eby)cp8 0 ei

  A net force F accelerates a mas(j4kzp. d l5f;tt,9p9 fwkwvz br)nr3zng5 3ks m with an acceleration a. If the same net force is applied to mass 2m, then the acctb95.k5gkl 3np3(t,wz w r4f zvrp 9jd)kz fn;eleration will be

  A net force F acts on a mass m and produ ly5/pxdas; 4 g+xx.oo) h,kk(g r-t owyu.2shces an acceleration a. What acceleration results ioo)xg+2y/4- l.s;sxhkx5uo, r gdwp.( kyhtaf a net force 2F acts on mass 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. This cl1+amd gy*-: k; jy k(oz*fkdis an illustratijkza *g+yf:c dkm o ;1ld(yk-*on of

  Two cars collide head-on. At every moment du92,nish r5jzc)r nt 5zring 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 first. This is an5h nnrszz i5t )j29,cr example of

  If you exert a force F on an object, the force which the object o6;k7t4z;b)xq tov*uy0m pfx exerts on you wilm)7k;0;4 fzobtyq*pt x vx6uol

  Action-reaction force1otlmd4 7p2 i5u+zg oq ubi)v,s

  Action-reaction forces ar v idj*rv;b8.2 yicugd.dr5d1e

  A 20-ton truck collides wizfbc(gq/o)1z. / s49 oxbkjblth a 1500-lb car and causes a lot of damage to the car. Since a lot of damage is dox .9lzjb g1bkcf(qz/sbo )/4one on the car

  An object of mass m sits on a flat table. The Earth pulls on tu*; 9y wysj(zeqdy9*ihis object with force mg, which we will call the action force. What iss y;(*w*y zy9equ 9idj the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The **ramcm;v xkf) +r 0urEarth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force,rcuv0 r* m xrfm);ka*+" what is the "reaction force"?

  Your bat hits the ball pitched to you w3 qrfof c02 kp-ztz7r4ith a 1500-N instantaneous force. The ball hz -frqkr pc0f34o2 7ztits the bat with an instantaneous force, whose magnitude is

State Newton's three q p 3c 4xz;k r+mvjwyk60a4q*glaws.

  Mass and weight

  The acceleration due to grkj-kn ;c9),r bt8vfv davity is lower on the Moon than on Earth. Which of the following is true about the mass and weight of v9cdkn8 jkvtb- r,f;)an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a distance iz0i lyjo p/,k2sxp -5xs

  Who has a greater weight to mass ratiorqj9z oi0 /5dw, a person weighing 400 N or a person weighi5ozqid0/w 9j rng 600 N?

  A stone is thrown straight up.pbs: bi-r 7v0p At the top of its path, the net force acting on is0pvb- 7b: prit is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from t+3au3u njxw5k he same height. Ignore air resistance. Compare their accelerationsj3+5x awu3 knu.

  A brick and a feather fall to the earth at theig/ :mmty:ca+wv;x*fz0 j1aqjr respective terminal velocities. Which object :mq+a:tja0 c 1jz*v;w/mgxfy experiences the greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an vpxgp9h/ qexb 1*7r 8zefw s5+elevator. The elevator is moving up ppxxswfrgez+/*eq987 b51 vhat constant speed. What is the tension in the string?

  An object of mass m is hanging by a string f/i1 rx/.azxhy6eq17qajc -garom the ceiling of an elevator. The elevator is moving upward, but slowing down. What is the tension in the s-q17 6a1x/h jy.iacq raegz x/tring?

  The force that keeps you from slidi, qffjuv /lm,n/,v ;: bd3k -beypohbq:82 qhong on an icy sidewalk is

  It's more difficult to start moving a heavy cart bg(:zmk : jfe(:qmhst m5d5) yian89*d2bj nnon from rest than it is to keep pushing it whs 5d2e *m (5bdi:j 9fknn)my: (: qajm8ztbngith constant velocity, because

  A horizontal force accelerates a box from rest across a hrfbry9 ccb7dt7y f xi*1o;(5vorizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditv;d7x(7 rcrbfotyci59f 1b*y ions remain the same with the exception that the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constantx27f 8gqfcv0i78mmvl velocity. Thus we can dedxffg 7lmc0i7 v82q8mvuce that

  A block of mass M slides down a frictionless plane inclined at an angle qm -apus1q9m: f with the horizontal. The normal reaction force exerted1 fm-s:m9uaqp by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q wio:0a4toox( gc th the horizontal. The normal reaction force exerted by the plane on the block is direct(g :o4o0caoxt ed

  A block of mass M slides down a frictionless plane inclined at an 6; di0w nr5ptyangle q with the horizontal. Tpri;5w6yd0 nthe gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simuly dy,0k.;x hpktaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being rkd.xkyyp h ,0;eleased.

  An object sits on a frictiob(zj mw2..5 fwo 1bjkhnless surface. A 16-N force is applied to the object, and it accelerat 5hb(.b 2kwzf o.j1jmwes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate fru f/ 5mskub0g7l) l:(:zyuzu5lyuh :d2j p x1qom rest to 27 m/s in 7.0 s. What is the average forward force on 1 y h 5spuf:u:j2)5 umxlb ldl7q k/(:uzuz0gythe car?

  Starting from rest, fgr n)hpnq(188hlyy4:v/s tc- (bfe ha 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is theh4r ) n:n(yphebsqv8 h /fcyg(8f-1lt net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket,2iz+x ;mlger which acquires a speed of 50.0 m/s aftergl,e+zri 2x;m 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 you push a 10-kg mass f1gick l 8tnb3vv* 6we9rom reg*c1l6 vk ewi398btnvst,

  What is the mass of a /c cz4t: aitd1person who weighs 110 lb?

  What is the mass of an object that weis 9hr6weun og;w,ih51 ghs 250 N on the surface of the Earth where the acceleration due noih;g5es wu,h1w 9r6 to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What is 5 rnl8s5di(1n nfh- ef21azmr the mass of the object on the surface of the Moon where the acceleration due to gravity is ois 1 5dfazf r-m1852nnhln (ernly 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B wei(h1onhzedvom))3 mq .ghs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses ofme) q d)(o1.voh3 hnzm the objects.

  Sue and Sean are having a tug-of-war by 6.iv-se lmt .ppulling on opposite ends of a 5.0-kg rope. Su vleip 6.mt.-se 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 on a level frictionless surface. A force F un enps 5ek;yoz)1 nw 54d wp*0x*fkt3acts on the stfxpn p we0e;*su3 ywotk5kdz51 4 n)*nack, 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. ufu s)2 u4q-p+l3pjs yz8nrh4 What will the scale be readsyp2lur4n- )pjufq4 zsu3 +h8ing 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 the3nz s,;q8yn)r k 4dsbm person is 60.0 kg and the elevator accelerates downward with an accelerationks qrb ;s8y,4nn)mdz3 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 iqqrx3 io.z;+is 60.0 kg and the elevator accelxrio +z3i;.q qerates 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 m51-xcp .y rp.q/nor +bu, kismass. One force has a magnitude of 8.0 N and is directed x+.bu rsi1mpnck5 o - p.q/ry,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 th6dn wesepe6. 9e 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 is the minimum stopping distance if the load is not to slide forward intw n9e6sepe6d .o the cab?

  An object of mass 6000 fc-fx,pcib9** y:xm vkg rests 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 trucx, vcxyi -p*:9mfcfb* k 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 sho(8znirpccw 2-wn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the mac8z-( 2prwnci gnitude of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown e. j3-hy 4iyifin Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in iy34f.-y ejh ithe string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on at ek/z9r 5cjt7/f9lwlsb 1f9y smooth horizontal floor with a force of 100 N in/c5 fkeflt1rjb/9 9t l7wzy9 s 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 f6e;z; (yonr xhorizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass of the box and the books is 40.0 kg, what is the nofre xo(n yz;6;rmal force on the box?

  A traffic light of weight 100 N is supported by two ropes as shg)yc((-. qa8; 1oaiqckpcimtown in Fig. 4-2. What are tc;.pa8aqg)c(y -moc(1i i qkthe tensions in the ropes?

  In Fig. 4-2, if the tensions ;sz kr6 b)ov)y3)vjwiin the ropes are 50 N, what is the mass of the traffic light?v);jvz6 )oksyb iw)3r

  Two boxes of masses m and 2m are in contact with each other on a frictionless ez/,q6ay3f oc surface. (See Fig. 4-3.) What is the accele/ czyeqfo36a ,ration of the more massive box?

  Two boxes of masses m and 2m are in contact with 9pq;+lz hvg; oeach other on a frictionless surface. (See Fig. 4-3.) What is the net fp vlhzgo+ ;q9;orce on the more massive box?

  Two boxes of masses m and 2m are connected by a ruc sechh2;3 6fpu /igcx*c(na/ 28mpoope. (See Fig. 4-4.) If the forward force on the more massive box h pfxgmcuh8e3 2/;(nio*upa/ cs26ccis F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Figvp3w 5j e2pzh. *8k )cbma3wqa. 4-4.) If the forward force on the more massivea*pm5a.qw k3p2 8)jzwc3 e hvb box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a poc af)065wob j(8oyss ulley as shown in Fig. 4-5. Box I of ma0obsowcj8ysoa)5 f ( 6ss
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 frsd ab)px 2nxu,3tvizv5vp7r * 3+pwk1uj7fq )ictions between a 3.0-kg box and a desk are 0.40 au7i1pwp jk)2a*xr f bv5p3xdzvq3 )ns ,7 t+vund 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 plastw/20*geg yajuic on wood are 0.50 and 0.40, j0u2 g/g*ywae
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. 7u5b b s:haap* 89pgmzIt slows and comes to a stop with a constanz7h bm b:9*8gp5aas upt 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 5.0-N force. ne5y;ui4pz, rn 3/hs q 7ckhb6n -joa8 A 3.0-N frictsu,qhzb3p4 ; a7nhc 8ye6 ro5ikn-j/nion force retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerates a 4n1t-vj8)s nag .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 gtoumf s- 1v n3o13p(e *8adtau6c1pkh1f5aj jiven an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between thmn11 c1j1d(-va5uf oe 6 usa h3ofa*8j3 tptkpe puck and the ice?

  During the investigation of 9cld(ibim9 t e ;liw :(a((wida traffic accident, police find skid marks 90.0 m long. They determine the coefficientt;ili9(: 9i( d( m ew(claibwd 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 j7kjwp77l, *wuxtvq p8 w,+ws 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, what is the static friction7,8pu+,kpww7* s ql w7jtwxvj force on the less massive box?

  Two boxes of masses m and 3mh hs:p:lh:rs) are stacked. (See Fig. 4-6.) The surface between the more massive box and the horizontal surface is smooth )lhr :h :sshp: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 inclined plane. 1r/mjr9w9mal The plane is inclined at an angle of a/l9 jrwmr9 m1$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hh6 *ig y-zrdaq7dou198 hf9c ni cif2.ill 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 u2.hw p-5o8iiluwvzmrh23 ( za smooth inclined 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 inclined plane tilted atp+h1ot7k2qdhyea; bm0 v7g 4e 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 kzt.41y 2*c9h xdw9xwk2co6b qjb(gdplane, at a constant velocity of 6.0 m ( tbq z24wj x9k1o2kg*wdb.9hy 6xdcc/s.
What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?

  An object with a massldd6 uadm6f07s1. 4vn ;rnj51 fvh vtf m slides 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 rough uh.yp,z-n v. i$37^{\circ}$ 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 surd:2ux: tijvzwya7e/oli6z4o2 f m :5 kface. The cable attached to the log makes an angle oft 27iof zyeo6v5/ m:d xulwj2 ::ia4zk $30.0^{\circ}$ 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 pzlc x md:kz++y gh387rest on a rough inclined plane tilted at an angle ofpgz3k +yhd:x7lzc+m8 $33.5^{\circ}$ 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 anr9rx)s:kit j6 inclined plane. The angle of incline is gradually increased until the objec 9jtx:)s 6rkirt begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?