Which of Newton's laws bes)xou(qn)sr0 (cc y8bnl1m 2zdt explains why motorists should buckle-up?

  When you sit on a chair, the resultant force on yo v ,0e(4omg0 6wtybufzpeo9n*1uhsr)u is

  In the absence of an externx:c(iq -u a +unvbm1u3al force, a moving object will

  When the rocket engia39vho);nou txp+ot93g4 jcg nes on the starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty space, thegoo hv; at3jt3n)9gxpc+4 u9 o starship will

  A rocket moves through empty space in a straight line with constant speed. I)3g o xs95j tl)fkpw,rt is far from the gravitational effect of any star or planet. Under these conditions, the force that must be applied to the rocket inlj3,o)t9p )kgfw5r sx order to sustain its motion is

  You are standing in a movinga2edi7f3 .r)h :cyxhd 8g bh:d bus, facing forward, and you suddenly fall forward. You can imply ahhgdh:b y:73e 8dic2df.x) r from this that the bus's

  You are standing in a moving bus, facing ntqb4rdh m00936jq jrforward, and you suddenly fall forward as the bus comes to an4mqj 0r3d9 b06jrqh tn immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. Describe the motion of the obje/, dv2 jc:b z94dpk(ajdx,h5/gu ;nnipr zml/ct.

  The acceleration of an object is dmnwu: b eiluu-9;t2-lk 5nw 1inversely proportional to

  A net force F accelerates a rvl(i0bz7tn ejhq;:ra:g z1m hww c1+ *a 5lj)mass m with an acceleration a. If the same net force is :g zvh: l+brrejq)1h;lwi 5mw *7aj0z1(cn ta applied to mass 2m, then the acceleration will be

  A net force F acts on a mass m and produces an acceleration a. What acceleratit z)5:k x,rwh oyxgp+)on results if a net force 2F acts on mass xr gktz:pxoh)5,+)wy 4m?

  If you blow up a balloon, and then release it, the balloon will fly away. Thu7zr31m l(jxq7 3 rda7fetye6is i 71edj6lr 7fzu (e 3yrqxam37ts an illustration of

  Two cars collide head-on. /dy42w5bv ln+xvxh of pz-3;x At every moment during the collision, the magnitude of the force the first car exerts on the second is exactly equalb35xl / zwxhv-d;4o2xyp fv+n 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 tgsf *p q37eh.jh04tg an object, the force which the object exerts on you wilsfhh 7g0ptj 3tg.q* e4l

  Action-reaction forces4h6jt cxp 1j3ihl)z7g h n ozh-5;acz4

  Action-reaction forces ari+.-hy.wu adz e

  A 20-ton truck collides with a 1500-lb car and causes a lot of damage tlkjfk g +uq./7o the car. Since a lot of damaggu/ kj flk.q7+e is done on the car

  An object of mass m sits on a flat table. The Earth pulls on this object with y shh92 t sl6lugp3,r3force mg, which we will call the ac6g l2,hspslr3t u3 h9ytion force. What is the reaction force?

  A child's toy is suspended from the ceiling by means of a string. The Earth puzx4 0j-qb +hwalls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction fo+0-hxaz4b jqwrce"?

  Your bat hits the ball pitched to you with a 1500-N instantaneous force. 2dik6 qb:zmg 2 The ball hiti2bkm26z q:gd s the bat with an instantaneous force, whose magnitude is

State Newton's three law gn -j/0n-if g9)q u.hctn*dsws.

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Earth. Which of 0m95 s-t*cskbabiy2 z the following is true about the mass and weight of an astronaut on thsm-0ksby95at iz 2b*c e Moon's surface, compared to Earth?

  An example of a force which acts at a dista9x v:r4 i 6wf-bs,tvchnce is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person weign9esb,/.xk ac0zo lo: z:lo6jls 0oz9a.:6:ln j obk,cz x/oehing 600 N?

  A stone is thrown straight up. At the top of its path, the net force act1ris;0b d6yaling on it isby6 1ls0i ;dra

  A 20-N weight and a 5.0-N weight are dropped simultaneously fro 2/qv 96; kv *+bvej)yhbh+sozrt)oky m the same height. Ignoqvo)hkrk+h 6v)y2bv9 tsz b o/e+ j*y;re air resistance. Compare their accelerations.

  A brick and a feather fall 5 6 d 50+h6zokhcmgpxlto the earth at their respective terminal velocities. Which object experiences thel6k5dx pz+5 chh60ogm greater force of air friction?

  An object of mass m is hanging by a string from the 1d 7m( bloo3*z( mbzcuj/ncv6 ceiling of an elevator. The elevazumzmcod/7(b16 oc *n3j l b(vtor is moving up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a sty:28w vcez1 erring from the ceiling of an elevator. The elevator is moving upward, but slowing downzr:ewv 1yc82e. What is the tension in the string?

  The force that keeps you from sliding*k 6ww0fmzi1o on an icy sidewalk is

  It's more difficult to start moving (ahx (pe8e8vmw-iqn; a heavy carton from rest than it is to keep pushing e; (xh8q 8-ea nipwm(vit with constant velocity, because

  A horizontal force accelerates a box from rest across a horizontal surface (frhee 8x.:(b bmdiction is present) at a constant rate. The experiment is repee.b: (hebdx m8ated, and all conditions 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 constant velocity. Thus we tx , )lx5mq/cycan deduce thlx) x qyt5cm,/at

  A block of mass M slides down a frictionless plane inclined at an angle q withtqm iu8ljhxbcpdq7028.ct8 4 the horizontal. The normal reaction force exerted by the plane 78h0t 2q88c. cjqldtip4mxbu on the block is

  A block of mass M slides down a frictionless plane inclined at an angle q )91 :lazmyxo* aylp.hkqm/9u with the horizontal. The normal reaction force m *.apu xzao)1yh :9q km/ll9yexerted by the plane on the block is directed

  A block of mass M slides down a frictionless plane incenq7aulqhb 79zfo/ k2 -:s4 ohlined at an angle q with th-b e9zhuo/fn4s alokqq2:h77e horizontal. The gravitational force is directed

  Two toy cars (16 kg h.il663rp2,,+x sxzo rle/ l fwjb)vjand 2.0 kg) are released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statement which best del2we6r+/hjoz. ),l,3pl6 ivxx rsf bj scribes their acceleration after being released.

  An object sits on a fricti,st fi(h9k p*uonless surface. A 16-N force is applied to the object, and it(up his *kf9,t accelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can acceleratud5 f6x-a2 d+9dtyja je from rest to 27 m/s in 7.0 s. What is t + j-9u6d5xadjfyt2da he average forward force on the car?

  Starting from rest, a 4.0-kg body reaches a-* -sjw ,4ahgwal():uq evlfk speed of 8.0 m/s in 2.0 s. What is the net fors)fkah uagvlw4:qw-le , (* -jce acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a spe)1hvj+yxpdlko+w 2:u ed of 50.0 m/s afterwj +u1lovxy:p+)d h k2 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-kgie,tpvzvz: ) ,09p cj/t zay9y mass with the same force that you push a 10-kg mass from reszip)je, 0,vacztp/ t99vzy :yt,

  What is the mass of a person who weighscjuqaq-t8j bf 888jg) 110 lb?

  What is the mass of an object that weighs 250 N on the surface of thl owe ;8ej4i3ue Earth where the acce8we; 4luej3o ileration due 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 og8 o.g-crxdkzjj7m 9 2yx7y 78pqxvaq z;v :n)n the surface of the7x ng8qz- 8k:)2m yjzyg ;77xqj9opdx.vr acv Moon where the acceleration due to gravity is only 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and ov h.pd x:dwr68bject B weighs 40 N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of8dpd.x: hrwv 6 the objects.

  Sue and Sean are having a tug-of-war by pu/u:husenr aay ;0,9s:tnlpr.q 3w2er lling on opposite ends of a 5.0-kg rope. Sue pulls wln a 9as/qu,nr0prtwu:r .;32s :yeheith 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 acts on thepmos./ oo ex;*2v3mae stack, anv *a; oxp2/.esm3om eod 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. What will tms) 1qizijw 2o3hj);y he scale be readi31jsi2)j) ; woy mzhiqng when the elevator is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mas; c4 h+yzcrud1s of the person is 60.0 kg 1cd z4yucrh;+and the elevator 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 the mass of the person is 60.0 4lvn r2q4zhy,kg and the elevator accelerates upwardnv l2h,4r z4yq 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 men: 4 murdn0*2axip2nass. One force has a magnitude of 8.0 N and is dip0ndnn2e2: 4 xua*im rrected 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 oqk*8 u js 2r7io.oqxy( c3vqw1n 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 truck is jq (oruxc27wkq s8o*ivy. 1q3 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 kg3v2pzv71u-aifnu:l:a) *dfbh8r pg s 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 truck is traveling 15 m/s, what is the minimum stopping time if the load is not to slide forward into th upaa-:vpb8 vr*ud3sl g2)zn 7:f1fih e cab?

  In the Atwood machine shown in Fig. 4-1, if yui xfltjz4t32 z9a i54jf29nqvu3/a M = 0.60 kg and m = 0.40 kg, what is the magnitude3futy9xj 9l z3v5zi q4 4a2nujti 2a/f of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine swqjg;.q )dn)il qq38 drizhw. (j23b jhown in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ir8idj).2q( jqj .blqi)wqh 3dgw 3;n zgnore friction and the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor withbzf;.(u1 rg uj a force of 100 N;uf (jgbr zu.1 in 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 booksb3akfy5 b)xls2mvm si kf1299 on a smooth horizontal 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, wyikv2akbsm1xl)m2 f93f b 9 5shat is the normal force on the box?

  A traffic light of weight 100 N is supported by two odosw ,kc u4n.) 1bs5hropes as shown in Fig. 4-2. What h ,)sdw cus.5nokb14o are the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is t ecu1g-f37rii he mass of the traffic light-i3rg7 c1ieu f?

  Two boxes of masses m and 2m are in contact ee59n.kyr(l2 v jmo5zc:b/t lwith each other on a frictionless surface. (See Fel9 ov ln:5tb.z5kcm(e yrj/ 2ig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m avh zvuz,)pkqoo)gj(,1/o*z8bme-ez nd 2m are in contact with each other on a frictionless surface. (See Fig. 4-3.) What is)z ez,-zv/e ,u*mbh) k o1pv8(oo jgqz the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4v uj:x( q1vaz4v;)o:(e t fo x3y:cova-4.) If the forward force on the more massive box is F, whato34 vv(xu vetz): yav1xf ;aoc(jqo:: is the tension in the connecting rope?

  Two boxes of masses m and 2m are conna2x/h 6kl 5hq-n 3vyje.n(xjvected by a rope. (See Fig. 4-4.) If the forward force on tx3h2jan/- y he(qn vj6 lv.x5khe more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord runn2b;yygytt0 i:nu wun+u,+mm+ ing over a pulley as shown in Fig. 4-5. Boxm;n +0nuit y,wu+2y+u my:gbt I 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 betwem*zy2jhung,she,)p8(a8b j0 dm o)q men 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 ,pugqm jz2hae8 s,)yj8)o(d b n*m0h mforce is applied to the box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50 a ceys:) wfk6/y*kjwluh6-*scp 3ju h.nd 0.wwc :yksfs*6yh /ep).-hu3jl*k6j cu40,
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 an+,ppt kq pcv(9d comes to a stop with a constant acceleration of,q(ppt+ kpv 9c -$2.45 \; m/s^2$. 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-Nb1-frgz*r w4srj-c)/7 px sri force. A 3.0-N friction force retards the motion. What is the acs)f/ c41 pzrrx rjs-b7*igwr-celeration of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg massvnhxwh m m3w* 6nvac-0eu9g3 0m-+tfi, 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, a47m2w ftn76/(f;7 t7e pkdm urm fdaqo puck is given an initial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction n7 /mkwfr2e7;7 tm4(qu6oadm7fd p ftbetween the puck and the ice?

  During the investigation of a traffic accident, police find skid)sze- j+ fza-gy)5a 9:6quhcratgtp . 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 care y:9az)+q6a sjtrhf5-t )-zacgp g .u when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig.9wa ler-moh6 q,g68lh 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 o,w6-m r 9ehgaolq 86lhn the less massive box?

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surlsn 6kwe / v+hkg: )as;dw/2jfface 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 nosag2 ehsl):dj 6f wvwk /k/+;nt slide on the more massive box, what is the coefficient of static friction between the boxes?

  An object is on a frictionless ine1l9fb,a* fl+b omi.ul(1x lh ns2tk6clined plane. The plane is inclined at an angle of mul9blb 6oflxas( f,e2 k1 +t.lnhi*1$30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill tha b9fttdo)*k6di q4p*at 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 idp4 +z+8yftlo2(qr dd nclined 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 smooth4 +:p1r 5 11 t)ytpyylodzyatr 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 constant velocity oas bdu cgyxc9+8j7;sm ;uy pay 6dj2:zh:c0x+ f 6.0 ms yuya gd0jc+u8cz+sad h ycj2m;p;7bx:9x6:/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 mak uc5xg/)2j 8romasf+u2s70, aq vdslides 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 slb 49v-ec8cv(anwin8k ides 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 roug;guaxnae, *2ogn0oj6l pj i:hr7r i+( h surface. The cable attached to the log mal ug;ir:oe g 0jh*,xa 7pjn+r6on2(aikes 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 r/er3ky6 j4rvfv ;,jogough inclined plane tilted at an angle y 6kr3vv;4r/ j,gjoefof $33.5^{\circ}$ 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 ij a.gr+8vb) stnclined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction bes8j gar vtb.+)tween the object and the plane?