Which of Newton's laws best explains whyyk69l n-wx6dn26jzhn99ma xq motorists should buckle-up?

  When you sit on a chair, the i;yxt eiqk qmh*,1u,oq9b5/mza k. t9resultant force on you is

  In the absence of an externalft fj0/pw65bm c3 eip- force, a moving object will

  When the rocket enginboa:h oy/r; gwa(ai 92es on the starship NO-PAIN-NO-GAIN are suddenly turned off, while trave9r(aig/; oyh w: ao2baling in empty space, the starship will

  A rocket moves through empty space in a straight line with constant sprgx4vn mq) /4peed. It is far from the gravitational effect of any star or planet. Under these conditions, m4v/p x gn4rq)the force that must be applied to the rocket in order to sustain its motion is

  You are standing in a moving bus, facing forward, and you suddenly fall forwcfox;2nk m ,-vard.2 xmokv,c-fn; You can imply from this that the bus's

  You are standing in a moving bus, facing forward, and you qx+f63kirrv myn)tb1 ih)4x, suddenly fall forward as the bus comes to ak)3+t, rmb1 hnyv4x6 xrii)fqn immediate stop. What force caused you to fall forward?

  A constant net force acts on an ob bubomtnyu79n:4wf+o 5g:6pd v 0a3sfject. Describe the motion of the object.

  The acceleration of an object is i:gm9:ztmd-j )gfw,j r nversely proportional to

  A net force F accelerates a mass m with an acceleration a. Ifqhevj94slq3 l1i)hnwy+ g (b0 hbf(h) the same net forceje h()q9q+l s4 b0g)n3bh(i1w hhvf yl is applied to mass 2m, then the acceleration will be

  A net force F acts on a mass m ab+,xdzxa5 o-znd produces an acceleration a. What acceleration results if a net fo, -bx+5xazdzorce 2F acts on mass 4m?

  If you blow up a ballogu*s uca0s2. -v k *xpy80fxhwon, and then release it, the balloon will fly away. This is an illustration f2 wycukusap* -08v.0gsxhx *of

  Two cars collide head-on. At every moment ejwrncx201rbkvgqe8+,k .b 4in kp/+ during the collision, the magnitude of the force the first 1kvbn nx/++iq jk.4bec,k pewr 80 2rgcar 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 oueueij 2m:7a.)ixt x /n an object, the force which the object exerts on you wil/muea:ej i7xi2.utx) l

  Action-reaction forcndb :k21i: *lqxhy,ajh - k6uees

  Action-reaction forcep z)uw+33s fbj*3hvcq s are

  A 20-ton truck collides with a 1500-lb car and causes a lot of damnq+zzp*yg0 zdgjmvq kd*0(+ 7age to the car. Since a lot of 0z( qvz70dg*z*nq dpkg+jmy + damage is done on the car

  An object of mass m sits on a flat table. The Earth pulls on .yp1gg2q0 ob zthis object with force mg, which we will call the action force. What is the reacbg.zy gq1 p02otion force?

  A child's toy is suspended from the ceiling by means of a strink73: /jul mhj qnqir.;g. The Earth pulls down7 jm hjl/k ;:irnq3q.uward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

  Your bat hits the ball pitched to you with a 1500-N instanb yx+dff6zogx67nerkf .lk:eu3p :(8taneous force. The ball hits the bat with an instantaneoe+: 86g:ul fy kxn 3dpz.exf 6fr7(kbous force, whose magnitude is

State Newton's three lawsue.9n s55m8p niq2ju y.

  Mass and weight

  The acceleration due bi*utdr6q*d 9z:k a8m to gravity is lower on the Moon than on Earth. Which of the following is true about the mas9krdd:m qu a* b*86ztis and weight of an astronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a dist.81ug+ra x/ 4xv +wb kbaygchjs2) g7aance is

  Who has a greater weight to malb.,l ftky +:b1 luvxcskk9. 9ss ratio, a person weighing 400 N or a person weig9b+ :xu v.ktl9f cyk ks.lb,1lhing 600 N?

  A stone is thrown straight up. At the top of its path, the net force actp 195jgp,ob jaing on ijpao,p 591gj bt is

  A 20-N weight and a 5.0-N weight are dropped simultaneously from the same heen3 c -faz)ru3ight. Ignore air resistanua3-cf 3ernz) ce. Compare their accelerations.

  A brick and a feather fall to the earth at their respective terminal ao9hl;7 zh0lt velocities. Which object experiences lzao7h0 9t ;hlthe greater force of air friction?

  An object of mass m is hanging by a string from the ceiling of an elbop. 4w7y fi hs7 pacb8-mz;f6evator. The elevator is moving up at constant speed. What is the tension in the ; 7b hp467yso fz8wcmp-i fa.bstring?

  An object of mass m is hanging by a string from the ceiling of anta.zu+n+ 2 v+q,eq zmk elevator. The elevator is moving upward, but slowing down. What is the tension in the strina.q +zqm +v+ nu2k,etzg?

  The force that keeps you from slid d1vddu+y: ie;ing on an icy sidewalk is

  It's more difficult to start moving a heavy car7vive lu g3y5;ton from rest than it is to keep pushing it with cone 37vlgiuv;y5 stant velocity, because

  A horizontal force accelerates a box from rest across a horizof/mhm a +-nf:0vreweg kl-h:8 ntal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception thf n8-w 0hmkh+el :afverg-/m:at the horizontal force is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at constant velocit-:f;tf/r hptty. Thus we can deduce /:fptht;tr f- that

  A block of mass M slides down a frictionless plane inclind/hb 6t nsy6m/uty0e /ed at an angle q with the horizontal. The n6my/yh 0d6ts /enbu /tormal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane z (uoe25ebeo .0iwfi.inclined at an angle q with the heei i( w052o..o bfuzeorizontal. The normal reaction force exerted by the plane on the block is directed

  A block of mass M slides down a fric5pen 6f)top9 ltionless plane inclined at an angle q with the horizo5p f9 pltoe6n)ntal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) agi : cg79u5ttp zv2cwvg)e 09bre released simultaneously on an inclined plane that makes an angle of 30e with the horizontal. Make a statecbvep0t9 z2u 579igg:w c) tgvment which best describes their acceleration after being released.

  An object sits on a frictionless sq yf;9ui 9e1ekurface. A 16-N force is applied to the object, and it accelerates a9qy ;ie1feu 9kt $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from rest to 27 m/s in 7.0 s. What n i+0j,gtsc)l is the avera lnj) 0citsg,+ge forward force on the car?

  Starting from rest, a 4 m y8av.,iib-ycu5xo g8qo:k9.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What is the net force acting on themcxoy. o:kvy58q- g,8aibi 9 u body?

  An antitank weapon fires a 3.00-kg lsl ;; qce9ki ny47lbnu8xh 5+rocket which acquires a speed of 50.0 m/s aft8qn 5ukl9 ic+by;xh4e s;l7lner 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 thag *czof /c4qm oa2(7snt you push a 10-kg mass from rest c(7nqfo*c4/o2a gms z,

  What is the mass of h2mf dfoq26 dwo l*7+l- t)voma person who weighs 110 lb?

  What is the mass of an object that weip)pjr -o4dk5((,najw.u5 x.g b oj iuwghs 250 N on the surface of the Earth where the acceleration ).5j.p owkj(pud nx(o4b wju,-gar i5 due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. What 5i89g7 tpkoz xis the mass of the object on the surface of the Moon where the acceleration due to gravity is only 1/6 of9o8zpig 7x5tk that on the Earth?

  Object A weighs 40 N on Earth, and object B weighs 40 N fm 2xpg)s27 7njodb;x on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of the objectsfn x27pm bos)dj7;2g x.

  Sue and Sean are having a tug-of-war by pulling on opposite ends of a 5.0-kg rgyuw5 91zp6dd ope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward 9g1wz5yp ud6 dSue at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force Fck8pxrt12j,s0nfx l; acts on the stack, and it at 1r8x2s,plfkxncj; 0 ccelerates 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 elevoa-mzjooc:gn 9 )/f t1ator. What will the scale be reading when the elevator is accelerating downward a19c:fo/j o) om a-gnztt $4.00 \; m/s^2$?

  A person on a scale rides in:56(m aanjz r r-8vomt an elevator. If the mass of the person is 60.0 kg and the elevator accelerates downward with amr8mv( t:an 5a6zorj-n 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 k5f5lbd*8dlma5o q)ek g and the elevator accelerates upward with an acceleration of l)k5dfdo 8lae *5qmb5$4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.0-kg sdy kvjx.s95g-3 b 2usmass. One force has a magnitude of 8.0 N and is directed due north. Th2u5-gkds.b3j9x sv yse 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 the flatbed of a truck. It is held in i93 +bk-wpalz7pg)rsy bw/1l place by metal brackets that can exert a maximum horizontal force of 9000 N. When the trucky7b9li)-salwb3r pp g wk1z/+ 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 ofj oe.l+hpp (7k a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 9000 N. Wh +e7jk.p(pohl en 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 +bvcv0y30jgy v8xlo-1, if M = 0.60 kg and m = 0.40 kg, what is the magnitude of the acceleration of the system? (Ignore friction and the mass of the pl8c0xg bvj1y+oy3 0v vulley.)

  In the Atwood machine shoa:qz3 uvxl-+w6; /n6t susdqdwn in Fig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore fr:/x6 dn6autu 3z -w qd;qssl+viction and the mass of the pulley.)

  A student pulls a box of-cg+md8x6)36cmy odei -vl he books on a smooth horizontal floor with a force of 100 N in a direction of mcgmdoxcy-6+l6i 8-h3dvee) $37^{\circ}$ 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 3 ya40hj5c+mwb6uwqp a smooth horizontal floor with a force of 100 N in a direction of 37.0e above the horizontal. If the mass om03u 4hj6pcyq ba w+w5f 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 by two ropes as shown in x7k:m )d iwfx4fnosvh+ o )wiu(/d7m6gd.q7b Fig. 4-2. What are the tex 4f mi7k)soo w7ix)6h.dbd /gw +(d:nfqmu 7vnsions in the ropes?

  In Fig. 4-2, if the tension8 jy78ncw3*: s zu6z:gpc/ br,f rtdprd b1:jhs in the ropes are 50 N, what is the mass of the traffic g :spj:z8cb* 7wz3 6nrybf1ctjrdp :u/r d,8hlight?

  Two boxes of masses m and 2m are ink( yq2;( l egp1blz3zq contact with each other on a frictionless surface. (See Fig. 4-3.) What is they 2ql (b;(z3kgpeq1zl acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact witjy+ pg.0vs4 krh each other on a frictionless surface. (See Fig.j.4r+ks0vgp y 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 Fisdns /n-d*ond 72 -xobg. 4-4.) If the forward force on the mo7-nnxdd oss/b * o-2ndre massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m az7q5xxrs ny*b1- z, vend 2m are connected by a rope. (See Fig. 4-4.) If the forward qez n15r z,7b s-xx*yvforce on the more massive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as shown uk9x t w:b6lj3m3w3dese4z .ain Fig. 4-5. Box Ik dzebt6 am49.j:3wsxwle 3 3u 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 betw7ygozj9 +:7s ifl qho(een a 3.0-kg box and a desk are 0.40 and 0.30, respectively.79zo: sf io+ (7hygjlq 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 fqxpx2(oo.wa 8or plastic on wood are 0.50 and 0.w.xop2 (8oaxq40,
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 th :hr9zn)d k4cxe +x direction. It slows and comes to a stop witn)x: dkh9cz r4h 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 5.0-N force. Ae t*v- * hws/u q8a+li7j-mkqm 3.0-N friction force retards the motion. What is the accelerat-hjaq *k7 tul+m8-smeiq/ *wvion of the object?

  A horizontal force of 5.0 N accelerates a 4.0-kg mass, from rest6x.fev3 z mkt3, 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 spe u0b3m zgs,or4)/oqbled of 10 m/s. It slides 50 m on the ice before4q)r0zbosl ,go/m b 3u it stops. What is the coefficient of kinetic friction between the puck and the ice?

  During the investigation of a traffic accident, poli3;2yh 2nku ehwfdv e.+o 6q7ymce 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. Estimate the speed of tnv wf2 o3he2uy7.+;m 6yeqdkh he car when the brakes were applied.

  Two boxes of masses ign 5 d-l/nc2 /y5vb0yuu* bpf3ommf,m 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.5bnuyd/b*3cgly5 ovmn, /f-m iup0f2 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 ;v+hvmi*yi+f 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 thi+y +vf i*vm;he 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-:vos(o) s cjv plane is inclined at an angle of)o-jc vvo: (ss $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides dog-aw o + /c-rsbvi*d/cwn a flat 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 pla1ne:ekfc1:j 95 xie..cjpav o ne 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 inclitt k;9p9 tane3r076y m d2py(lh mqmupcv8a *4ned 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 slidekiq:,l,m kotf, mg*ygfy+p 1j1dpb /5s directly down an inclined plane, at a constant velocity ofqg:i ygd*l+kbp m5t/1k fp,,1 fy, jom 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 slides.bj iiruv.03n n-7feg 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 rouo; *ttg9 ycmbr8zqc-6 gh $37^{\circ}$ 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 -nk6t3mb +titalong a rough surface. The cable attached to the log makes an anglen mit tt+b6-k3 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 releasef 6ds2gi5t*z6)m7 +mcd hzugwd from rest on a rough inclined plane tilted at an angle dh )t dif*62zw6u+zgmmc 7g5sof $33.5^{\circ}$ 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 inc; no3o pkohm6*line is gradually increased until the object begins to slide. The angle at which this occurs is q. What6km;onoo*hp3 is the coefficient of static friction between the object and the plane?