Which of Newton's laws best explains why motorists should* v2b;v luwj2svy4w p: buckle-up?

  When you sit on a chair, the resultant force on yo ur**ydvpd:cx +67jmku is

  In the absence of an external force,vgup:i2 -4)nqhl mb pzzty45 gwe0t6. a moving object will

  When the rocket engines on th 4 y-sqix2knj nmk ;40x-vnvi0e starship NO-PAIN-NO-GAIN are suddenly turned off, while traveling in empty spaceix0vn40xi v-4 s2qk;jm yn-kn, the starship will

  A rocket moves through empty space in a straight line with cog0q 9xbvuh r ol9j)yrx2,84qfnstant speed. It is far from the gravitational effect of any star or planet. Under these 8,qubq9h l0y4j2xoxv g)frr9 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 forward01235l8p vophek bm ir, and you suddenly fall forward. You can imply from thisbkvr8pphim5e0 l 123o that the bus's

  You are standing in a moving bus, facing l/q37/w ljbssforward, and you suddenly fall forward a/bw7q sll j/3ss the bus comes to an immediate stop. What force caused you to fall forward?

  A constant net force acts on an object. De6 9 (uejv:)vq 9dajtyoscribe the motion of the object.

  The acceleration of an object is qahc0xm-0h v) inversely proportional to

  A net force F accelerates a mass m with an acceleration a. If the same net forel6 o96qvr n 4tyl*/ljce is applied to mass 2m, then the accelerati/to 96lvrln64j*qely on will be

  A net force F acts on a mass m and produces an acceleratp c t4vs:;py.rar9rh7 ion a. What acceleration results if a net force 2Fpah;9v .4 y7rtrr sp:c acts on mass 4m?

  If you blow up a balloon, and then rej0x-fh nrxc ie0q:, 5rlease it, the balloon will fly away. This isx5fe hc,qi:xrn rj 0-0 an illustration of

  Two cars collide head-on. At every moment during t 9jmrl,ikscbhe.+0zj s4j b8 55,hq dmhe 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 fire8h,h rq 590b .s,s5klmjjjd+mb4czi st. This is an example of

  If you exert a force F on an 4zr1u :s/w r-z(as,pk:xwcsjmb t98d0 x *sydobject, the force which the object exerts on you wil mk: dz *x9t:b4 s-jzd,(sxswsypr/0 wru81cal

  Action-reaction forcox4/zdrd3 . zyuu2m;mes

  Action-reaction forc5 f9wal6v)myves are

  A 20-ton truck collides witi1henhu-tbs 7:f;g q/h a 1500-lb car and causes a lot of damage to the car. Since a lot of damage ibe:hf t-gnu71ihs / q;s done on the car

  An object of mass m sits on a flat table. The Earth pul33 z;6 catyl5+vwgmywls on this object with force mg, which we will call w33a 5+ycl gywz;6m tvthe action force. What is the reaction force?

  A child's toy is suspended fkf c;aajy;8v) f +fm-hrom the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction forcf f-c8vjhyaf+;k;m )ae"?

  Your bat hits the ball pitched to you with a 1500-N ins5xeo6e 88vce xtantaneous force. The ball hits the bat with an i exo68v8xe 5censtantaneous force, whose magnitude is

State Newton's three ;yu5-/8* 8 ccg za dxujcfbkc1laws.

  Mass and weight

  The acceleration due to gravity is urm6 po1co7tr +di)hmlp 4fp7* 8rx0c lower on the Moon than on Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Ep80 + c4u)t*r1dlxrfor p6 hioc7mp7marth?

  An example of a force xlavh9/q.bl0 which acts at a distance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a persovrzmn3m1j )b7n weighin)rb m7v1jzmn3g 600 N?

  A stone is thrown straih a*i4o nb ycp6xt.23yght up. At the top of its path, the net force acting on it isp63t* h4b2cy y xaion.

  A 20-N weight and a 5.0-N xam9 4-hrg t9sm;6hfhweight are dropped simultaneously from the same height. Ignore air resistance. Compare their acceler-m96gha htxsmfh9 r4;ations.

  A brick and a feather fall to the earth at their respective terminal veloc7*eoco1n1dmj(e 2nb-v n; uqjities. Which object experiences the gnen *1eqvjc7dj-bnm; (2o1uoreater force of air friction?

  An object of mass m is hanging by a string from the ceiling j81ks w e(b(z;b4rdil of an elevator. The elevator is moving up at constant speed. Wh(4 rl 18kd;wesjib bz(at is the tension in the string?

  An object of mass m is hanging by a string from the ceiling o5iztp, khj:g 6f an elevator. The elev tghzp ,6ki5:jator is moving upward, but slowing down. What is the tension in the string?

  The force that keeps youtj6hu pae5b.l)0+n mu from sliding on an icy sidewalk is

  It's more difficult to start moving a heavy carton from rest than it isz0 p0uabfj-mne4 8 v1ozz 4ui4 to keep pushing it with constant velocit 44-vmfp0a uiz4eb znu8o0j1zy, because

  A horizontal force accelerategz.ap3; tiuxti1 ;uu1s a box from rest across a horizontal surface (friction is present) at a constant rate. The experiment is repeated, and all conditions remain the same with the exception that the horizontal force is doubled. What happens to the buuiu 11 tzx; .ia;pgt3ox's acceleration?

  A packing crate slides down an inclined ramp at constant vel,;ccp*vn y*rl ocity. Thus we can deduce tnp*yclrv;*c , hat

  A block of mass M slides down a frictionless plane inclined at o+:qmrez7ee) t ouo*c ;gj: e4ge 5q-uan angle q with the hoej*7+ zo:t 5eg-g4q qr:uo; )ecomueerizontal. The normal reaction force exerted by the plane on the block is

  A block of mass M slides down a frictionless plane inclined at an angle,thau- il(t /(g7ukpfy 4bvs 64nrdl; q with the horizontal. The normal reaction force exerted by the plane 6 ni4gupl(,f(a-ldtrt u sv7; bk /4yhon the block is directed

  A block of mass M slides down a frictionless plane inclined at an angle q with 8o( fj2k hzkz tne30uspw.ae a+7kk(ipr *34jthe r 8itf7*jwaazk (koh3p .24jp+ s 3nuk0kee( zhorizontal. The gravitational force is directed

  Two toy cars (16 kg and 2.0 kg) are released simultaneously onr dzuhces,n.xpt1 3iq2 b;s:y3j9yf4 an inclined plane that makes an angle of 30e with the horizontal. Make a statement which b3n4c,rhb9fpjui t:yqyd3z2s.s ;x e1 est describes their acceleration after being released.

  An object sits on a frictionless surface. Au k2btli4r 8 m(fl3kb5 16-N force is applied to the object, and it accfuki5 blrm(4 3t 82blkelerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate fr ;j6rv(x: 2gpwv 9 2wsyrmez3hom rest to 27 m/s in 7.0 s. What is the z9wh6e2;: 2y3sj p vm vgr(wrxaverage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed of 8.0 m/s in 2.0 s. What qnz jjxn*)l.e i md+*b3;6ow zis the net force actixbimjn ezoz+ld*j);63q.*nw ng on the body?

  An antitank weapon fmx*b 3evw tgvxkxt4;s3t 1o++ires a 3.00-kg rocket which acquires a speed of 50.0 m/s after travelinbx m4*kt3o 3+ wvs1tx;+t vexgg
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 wir z -9pz1lyc5zth the same force that you push a 10-kg mass from restzyz-r1 9c l5zp,

  What is the mass of a person who weia /kwekdiuj4-*z-eeb j 9wzcu4h/m hn/-p 56v ghs 110 lb?

  What is the mass of an object that weighs 250 N h 6rc l,tm,srw3i p7e)4xyqsa4 e7 b3uon the surface of the Earth where the acceleration due to gravity i64 c3e e7uywts3li qmpb a, )hxr,s74rs $9.80 \; m/s^2$?

  An object has a mass of 60 kg on the Earth. 1dg e.eg+ ftza.e:0m x What is the mass of the object on tht a zmd eg1e:+fex.0.ge surface 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 40 mty 1tb ujwo,8e,s)mj48bwp:N on the Moon. The Moon's gravity is one sixth of Earth's. Compare the masses of the ob,8 ytobwj:s 84 1p mwbut,e)jmjects.

  Sue and Sean are having a tug-of-war by pulling on op /t ekn30w2uboposite ends of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates toward Sue2e nowt3 ubk0/ at $2.0 \; m/s^2$?

  A stack of books rests on a level frictionless surface. A force (p4,)fj2sp wuzuhce k4*nl g,F acts on the stack, and it pfehg ()2,4 wzku*s4nu,cp j laccelerates 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. W ,zs 54,dy-pvn /dl 0tmafix/ohat will the scale be reading when the elevator is accelerating doi od,yfn5m0vxa/4/ l,sp-t dzwnward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevator. If the ,ryn+rsfonx6x,alku ;u 5a 16mass of the person is 60.0 kg and the elevator acceyx;af u+5n sk ,u6oral6r,x1n lerates downward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  A person on a scale rides in ai89x;:qj4 kx2oywpspry d l-* n elevator. If the mass of the person is 60.0 kg ando -4yd*w9s yxq rp xj8lpi;k:2 the elevator accelerates upward with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.zzdwun8h- ;/pn.la0 a 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 the accel0a;z d/n.8al pnuwh z-eration of the mass?

  An object of mass 6000 kg rests on the flatbed of a truck. It s nbexa7qg x0d0 j-zvm/9;u5ris 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 into the ca0e;9jx n5s ax b7 d/vmuqgr-0zb?

  An object of mass 6000 kg rests on the flk8ei-)ap ipk +7lknl*8y )l tiatbed 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 minimu -)ikle78 lkk)pt+*a i8ilyn pm stopping time if the load is not to slide forward into the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.6,4d;t,zkb xqv;yt)jopw : s) vtbq;5u 0 kg and m = 0.40 kg, what is t bz)vto wvq u, ;:;k;pqdytb,sxt )45jhe magnitude of the acceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in F3srsk w718p) x- iu(sjiuq,of;xhe h(ig. 4-1, if M = 0.60 kg and m = 0.40 kg, what is the tension in the string? (Ignore friction and or(-1k qsi hesx,fhw(ju3uip) 7 x8s; the mass of the pulley.)

  A student pulls a box of books on a smooth horizontal floor with a force of ur;jq vh(ot2.m te9r-100 N in a dire r;v 9h-t2 mrjuo(qte.ction 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 with a force of 100k3 cc it5w.c 2m5se)lk* 3mppn 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 normal force on the b) p.3ltswp5ecmk3c2 5 nim*kcox?

  A traffic light of weight 100 N is supported by tpsk4 gi+x 27ip/4xxrtwo ropes as shown in Fig. 4-2. What are i7x2ipg4sk/rt+ xx4p the tensions in the ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass of i6, +9yj1oz)r(3tn nis yxmzl e9* orithe traffic ligh69y(rtre)zmoy*xl, 1sn3ni9i+i j zot?

  Two boxes of masses m and 2m are in contact with each other on a frictiony;p /xj:w+d 6jdu2kfr less surface. (See Fig.2/k +j: wydur; f6xpjd 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in contact with each other on a ip3r 4y 3 5 uhk*zxz5cacn*7fgfrictionless surface. (See Fig. nh r43i ck5cp**3z5fgzu7ya x4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m f ony;(lsk oshh:n;0y r0a sp 0.x3dl/are connected by a rope. (See Fig. 4-4.) If the forward force on the more massive box is F, what is the tension in the cdn a.;syk fson030prhl/l( yh: ;0 osxonnecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fie xc ub*p; duig:q*k..i3ht-yg. 4-4.) If the forward force on the more mgx*e;hq .-: ty. 3kciiupud*bassive 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 in hqt 6;ucaifgovz:;.*Fig. 4-5. Box I of*;c:gvhtf6z ai uo q;. 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 betwi .s 8h/c0eak0e5tgz keen a 3.0-kg box and a desk are 0.40 and 0.30, respectively. What is8agi50e e0 t/kkc.szh the net force on the box when a 15 N horizontal force is applied to the box?

  The coefficients of static and kinetic frictio lj(ne(;)mlkx4h/w 7oo+t d rxns for plastic on wood are 0.50 and 0.40o) tlo(x+; e xh7kjmd/rwn 4l(,
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/+ os ss licy3osfqx)qc7kcx s,/ opa8 2i/*v, the +x direction. It slows and comes to a stop ,ys 2si ,s )/k8 cscio7ax*oofsq//3pql+cxvwith 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 pulb5arnlfr kaao865 -6dled by a 5.0-N force. A 3.0-N friction force retards tr5k r6oal65ab-n 8adf he motion. What is the acceleration of the object?

  A horizontal force op*yh p2c;9hy if 5.0 N accelerates 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 initialjkh* 4pdzi6i(.lz p/ f speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic friction between the puck and the ich.64 f/dp*izk (izpjle?

  During the investigation of a traffic acciilbvb/z w.4 3vdent, police find skid marks 90.0 m long. They determine the coefficient of friction between the car's tires and thel v/ibw4 v.3zb 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 and 3m are stacked. (Sxg(jqrw.x; ; ;8yakt vee 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 q; xw. 8g a(xvjr;;tkythe 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. 4-6.) The surface ae ottb c) ds1-t310sybetween the more massive box and the horizontal surface is smooth and 1bde0s3- ay)ot s1ttcthe 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 plq5 up /+o(ttcyane is inclined at an anglcu(5t y+ptoq/ e of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides dow.-mry e x6fcgpk*+u7wn 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 in3jxbgzwumpo6b/gv dc8i)+lk l 9x1)x; .drx (clined 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 pny92n t:1c2+gfhwnv uafy1 2e lane 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 7sjy. u 8 g6j+m / :ofh-lx7ecn0lqlizjo*rx /velocity of 6.0 mn eq:s7l0m /hox7 j+/* lzxfju.c8ilry goj- 6/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 slidewm uhtw 6v7 0.tgjsxo0m7p5n7s 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 +c,r j-s,my ydslides 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 surf 7*y7wuloqo(( n, rjfwace. The cable attached to the log maker w*y,7j(uo 7n(lfoqws 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 rough incle+ff/.bicm b9 6rr: 4g:yutzgined plane tilted at an angle of 9y.:rtr6:fi /+e bg zbc gu4fm$33.5^{\circ}$ 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 inclinohlw2,6 v1okene/j*:g l 2nbee is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of stati1khg,l*el:oeb j6e/ w vo2 nn2c friction between the object and the plane?