Which of Newton's laws best explains why motorists should bucklw5:;u,sw ct,n vk s-rce-up?

  When you sit on a chair, the rtxb xe)3 to8n4esultant force on you is

  In the absence of an external force, a moving object wpz/lzqum9n the + p+/1fr i07yill

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turned v/xz.fub(:)aos2/ nf cbk .ew off, while traveling nu:z)(e oxb wfkb. a.2/sf /cvin empty space, the starship will

  A rocket moves through empty space in a straight line with constantcpcs,h-xb1*l ,ry*f , mnjpq2 speed. It is far from the gravitational effect of any star or planet. Under these conditions, the force that mun, xccsh-ym2*jpb q,,fr 1l*p st be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenly k4wyg8v9ac+7k u0 h z ys2kms)fall forward. You can imply fwkh70u asy8g9+kk4)zy vcsm2rom this that the bus's

  You are standing in a moving qq+y-t5xwirmsg53m)bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stoyqrm+- 5) ms5wqgt 3xip. What force caused you to fall forward?

  A constant net force acts on an o sg,h .oz)hew-,a*y+if z.8owyivsh*bject. Describe the motion of the object.

  The acceleration of an object is inversely pm d bna)7e4e7froportional to

  A net force F accelerates a mass m with an t y0z)k)j i*azjjb f 4j(*+gw(.h4 u4xgtocoxacceleration a. If the same net force is ag4bt o*c+0j(jzy tj huo4kz w(g*)fxi)ax4j.pplied to mass 2m, then the acceleration will be

  A net force F acts on a m kqil3 :gq,y68 zc7sz3 ywyhk0ass m and produces an acceleration a. What acceleration results isy7ciqwqy g36 08yl kz3z:hk,f a net force 2F acts on mass 4m?

  If you blow up a balloon, and then yj hdi 6 3x:a 5jr6nvvymk/(l-release it, the balloon will fly away. This is an illustration -j v6h/:xrmkvl aj5iny3 (d6 yof

  Two cars collide head-on. At everyoc .u5jf3jzknl7w cvs6v;v* ; moment during the collision, the magnitude of the force the first car ec6kolvn*j;wzu v .; svf75 c3jxerts 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 whioutf hjxmq71fcl:s3 7*45c q kch the object exerts on you wicfko5tjs7l 4q:*7 3m h x1qfcull

  Action-reaction force3zx0hi ir f,tb: l7qd) s atso4no,7-ps

  Action-reaction forces armgv4 v,2- kdsfe

  A 20-ton truck collides with a 1500-lb car and causes 4z6 .y fif17kq;a( j7rmhvjuya lot of damage to the car. Since a lot of damaghf6iy(;4k7y.jv aj quf 1 r7mze is done on the car

  An object of mass m sits ogqqecu y*fw+v2(*t x9 n a flat table. The Earth pulls on this object with force wy*e29tcqg(u *fxq + vmg, which we will call the action force. What is the reaction force?

  A child's toy is suspended from the ceiling by means ojpz r6+ +hbqcoz1xy+487rc mazu ,5xzxp b(p5f a string. The Earth pulls downward on the toy with its weight f7yxr8x+5a5mx1j46 z cp,+b( phzz z c+ borqpuorce of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you w6 pj5 xl2y)s i q/6f5emouurm ,ztc9k.ith a 1500-N instantaneous force. The ball hits thefuuj sy)9.z/i6mpmto c,lrq65 kex52 bat with an instantaneous force, whose magnitude is

State Newton's three lawse/f/qbz g ovr1.pr;0n .

  Mass and weight

  The acceleration due to gravity is lower on the Moon(usaayf8. scsa /:7: yoltm (y un/f(d than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, comcl8sf/(a (7/osafu. ytmsny:y :(dua pared to Earth?

  An example of a force which acts at a disc.4zo.o ;yc,w fjvgsnu9yr+/ tance is

  Who has a greater weight to mass ratio, a person weighing 400 N8 w7v4eicequ/2kq o2ei2t q( y or a person weighing 600 N?4 oewqtec2vi8q e/u7 i(q2ky2

  A stone is thrown straight up. At the top of its path, the net fvyujc-p)ktb1 :n te75orce acting on it7:)j-b p eknc5ytvu1 t is

  A 20-N weight and a 5.m2 2dii(wcs j:0-N weight are dropped simultaneously from the same height. Ignore air resi(w2jsim:d i2c stance. Compare their accelerations.

  A brick and a feather fall to the eart e,vwwhk+ kz1-9ru+z rh at their respective terminal velocities. Which object exwz+k-h k,z+w 1rv 9rueperiences the greater force of air friction?

  An object of mass m is hanging by a string from the ce nj4* w:cm xx54zraxy(iling of an elevator. The elevator is moving w:5x4(xajr x*4 cznmy up at constant speed. What is the tension in the string?

  An object of mass m is hanging by a string from the ceiling of an elevator. rpxp)77np0zht,ktj ,6zi / ca The elevator is moving upward, but slowing down. What is the tension in the ,)z 7rp6x an0i jpp/7z,htkc tstring?

  The force that keeps you from sliding ;2 ppbe/u 9kyeor/u)aon an icy sidewalk is

  It's more difficult to start moving a heavy carton from r/,+xg 8hcdrg+ t uue-oest than it is to keep pushin tu8x,dhe -o g/+gr+ucg it with constant velocity, because

  A horizontal force accelerates adn(f 6e2 yexxw qsarz: 97t5*2ltnba5 fak ((v box from rest across a horizontal surface (friction is present) at a constant rate. The7 * z(5 dvw 2ntxele(qa(y6ff 5ratx29n:sa bk experiment is repeated, 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 consttarwmaw yl;f 48 u49drn ):z,fant velocity. Thus we can deduce that afn9r84:r f awdyzmuw4,) ;lt

  A block of mass M slides down ad3k p8y /*8 h2)yzyxi+ibo eur+at7dw frictionless plane inclined at an angle q with the e doyyd u*rx+8a3/by +i)h7z w82itkp horizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a 7t p my ff2,vr4f;vh0o(pldq4frictionless plane inclined at an angle q with the horizontal. The normal reaction force exerted by the ph vpffpyl,dt07 4f(q4 2ro;mv lane on the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q withz +xq2 -stgn6a the horizontal. The gravitationantsq xz-+62ga l force is directed

  Two toy cars (16 kg and 2.0 kg) are relea 7(:6 pb jk0zode7nn4zq-gesksed simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a n7z q4pen j-6oke(g7:z s0dbkstatement which best describes their acceleration after being released.

  An object sits on a frictionless surface. A 16-N force is applied n7-qm1g.k1d * cwfd yxto the object, and it accelerawqmn-yc* g1f1.d kdx7tes at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from *5371d6xk6h ue d cun*vixnmhrest to 27 m/s in 7.0 s. What is the average forward force on the c d hnx536 k16*vxiundu*h7m ecar?

  Starting from rest, 42gs/s zbzvgagjtms )q5976;knz n g4a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on 4jvs/zmts6a gg7s nbgz5 z2 g);9nq4kthe body?

  An antitank weapon fires a 3.00-kg rocket wkseggi: 1533vvkktr sf80gp a3u m5s;hich acquires a speed of 50.0 m/s after travvf s3 :;k 338g5avu1rt g 5sk0isgmekpeling
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 *6cz8-1-zze* coar agifz sd5same force that you push a 10-kg mass from reszos i1cz6z adg 85**ec-az-rft,

  What is the mass of a persaocy :c2 ). /0vwigtqqrzxk)5on who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of th2o76wy-t :i.c 3vn/c nedo jvpe Earth where the acceleration dued.2ywtn j:76iecc 3o vn/-opv to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on f: j /u89 ,50/vnuwo ggorng7tvmi l)lthe Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is onl,r 7ul/ 9fmnu)0oi lowv8/tggv: n5jgy 1/6 of that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N on the Moo/q2 rdy 3n3/t ge6kvgzn. The Moon's gravity is one sixth of Earth's. Compare the masses of the objeezy g63q3 2r/v t/dkgncts.

  Sue and Sean are having1h raf(e6 u8xf a tug-of-war by pulling on opposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if th 6(heufxf1ra8e rope accelerates toward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force F acq4y9md 5r;d:j mkl6qvts on the sta vq45rmq k:dy;6 ljd9mck, 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 st2f1ox1 0uthylu vn-t ; zc25gtands on a scale in an elevator. What will the scale be reading when the elevato0gtu;z2t xlf5v u1-n 2 ht1oycr is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the mass of the person is65ubq h..l c 8uhio9cd 60.0 kg and the elevator accelerates downward w5bh uqo.lcu h.i9d86 cith 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 oqy1p,xw8 s1z:cff:v oxq0 0qz58lw y wf the person is 60.0 kg and the elevator af0sz8 ,1wpxwxwqoqy51q: lzcf :0 y8vccelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act s97ozqk0 sxe 0on a 5.0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the east has a magnitude of 6.0 N. What is ts 9sk07z 0eqoxhe acceleration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It is held in plac(5q qpcoi i8 x5uq3q85 mp5.g *hutrote by metal brackets that can exert a m5xhp gomq835q. uttu5op*(8i cr qi5q aximum 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. o*+6cs 4,j9q 0ziec;wtd;cref dv6 ie It is held in place by metal brackets that can exert a maximum d9tv4ii+e *zw6cf;s,eeorc dq;0jc 6horizontal 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 M9,c+3azkfx+h *pfhj v = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of +xv,ha*3zjk hcf p9f+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 = 0.40 kg, whatid2r .z80n3 rzj zrl ps+-+maj is the tension in the string? (Ignore friction and the mass of tpz3+8lrjza2-z0sr.m nji d +rhe pulley.)

  A student pulls a box of books on a smooth hor q/hy9x.a9ih, q60sv zp4o odpizontal floor with a force of 100 N qdsp4,0v zxiho 9p h9y 6/.qoain 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 ronw.vb7 9a t+a smooth horizontal floor with a force of 100 N in a direction of 37.0evrbo+.want9 7 above the horizontal. 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 b **;pqfqe)ezuy two ropes as shown in Fig. 4-2. What are the tensions iepzf ;*eu*q q)n the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what isu8p va 0gzvkc*5v +3dfuk w4o( the mass of the traffi8a53zdkvu0v(fvp*o+ucw4k g c light?

  Two boxes of masses m and 2m are in contact with each othe;xn:s3ciy1a l z:.dxrr on a frictionless surface. (See Fig. 4-3.) Wha1azxnir xds;.c::3 lyt is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each othe :k x*8wx8ray-gc5 yoa4riq7jr on a frictionless surface. (See Fig. 4-3.) What 5 8ry-4*a coixg:y 7xrwaqj8kis the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (Sz 4undslh)l;zt rl1+ p 8n,x8nee Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the 8tdrh+u4l ps18x ) nl;,z nnlzconnecting rope?

  Two boxes of masses m and 2m are connected by a5wki ann;sn)f-z.pcqp*yh w-n s24. 68r icpz rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is t.-cs i4r*zn kqy;5 aps.ni 2zwwc)nfphn8-p6he acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown in Fig. 4-5.(8h jx-ca o5r4/wcit c Booj8a/c w5t (xcri-c 4hx 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 betwt063ca9re z;r gw) qaueen a 3.0-kg box and a desk are 0.40 and 0.30, respectively. Whar0qcawet )gzu3r69; at is the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictionsy mf56k3glp2jnuf7 b2 for plastic on wood are 0.50 and 03mu fkpny26f j blg725.40,
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 comesc 88 r1e/glf82ba0flzokfzn e82p6ow to a stop with a constant acceleration 882/n1folk8zb ce6 e0ar z8wp 2folf gof -$2.45 \; m/s^2$. What is the coefficient of kinetic friction between the object and the floor?

  A 10-kg box sitting on a horizontal surfa+3xkjr n+b4ws ce is pulled by a 5.0-N force. A 3.0-N friction forcen k3+bsr w4j+x retards the motion. What is the acceleration of the object?

  A horizontal force of 5.0 N accelerat pt9djl cv39 l aa2q/brct ;w7(jmt-9zes 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 inwfa 9-1 4(tu z)dxgq yckkv3y6itial speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient -w6qyvx )f dg(a94ucty3 k1zk of kinetic friction between the puck and the ice?

  During the investigation of a trafz arw09 ,/yzo qzt2vk90pajp ,fic accident, police find 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. Esti z,0a0vty k9pr, wpojqz2 /za9mate the speed of the car when the brakes were applied.

  Two boxes of masses m and 3m are stacked. (j:ek:s ;6k owohg 8kse-z+) dzSee 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 h:zkd; zo)kj -kw goe8ss6e:+ 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 3m1lyxaz 0 y3xtp2/q5bz are stacked. (See Fig. 4-6.) The surface between the more massive box anz x52/ xl1yaqytpbz03d 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 coefficient of static friction between the boxes?

  An object is on a frictionless inclined plane. The plane is inclined at an ang. qo( /cub5oyvle ofuq5(yc. vo/ob $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a f;tp9 de cuhyo4x/ ik.n0om61flat 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 pl/ pf.,jkw8x liane 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 incline8zw0pyi re )/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 inclined plane, at a constant vmy 2nn3alc eq;6.b/sbelocity of n a n2bm6cse/b.lyq3; 6.0 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 sle9ca-:x : .b0sekn z9myhn e7yides 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 slides1kn omt 7 i3e; gw;45.u56dloeerou vp 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 surface9 8yb46 d ffxztx2ki*s. The cable attached to the log makes an ankb8f6 ztxfdiy94 2xs *gle 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 r4 rlyppl5hp/ mic1p6. ough inclined plane tilted at an angle of .pp i5/ 4plym1rlc6hp$33.5^{\circ}$ 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 incld3gyqjr: vb92 ine is gradually increased until the object begins to slide. The angle at which this occurs is q. Whatgjdbv:y32rq 9 is the coefficient of static friction between the object and the plane?