Which of Newton's laws best explains w zskjg 3w xewa(00 cg2ywxnh8+6q*5g lhy motorists should buckle-up?

  When you sit on a chair, the resultant force on you dgy ic l;tj6h5(f,o1omzs a( :is

  In the absence of an external force, a movuu3 ) 2;*zygcdi5yxi ming object will

  When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly turmv 8vobj0yza 8w4g6l1 ned off, while traveling in empty space, the starship 18gj6v 8wml40azyobv will

  A rocket moves through :mixv nelo c)5r )bi2k ::vi3aempty space in a straight line with constant speed. It is far from the gravitational effect of any star or planet.2o:iklvrc:3ii)nv me):a x 5b 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 bus, facing forward, and you suddenlyh)to sd;z1mnu tkl*8 pfe e05; fall forward. You can imply from this that the n*p8e0 m e u)k1lftdhts;z;o5 bus's

  You are standing in a moving bus, facing forward, and you suddenly falc a:w c9xt )9m wkv(1ijg3fzy.l forward as the bus comes to an immediate stop. What force caused you tvzt gmx iyw).cj(k39:w1ac 9fo fall forward?

  A constant net force acts on an object. Describe the motion oc r.4chvn b e0d:c7b3k gnxrn0a.2 c n)v5*ahkf the object.

  The acceleration of an object is inversely proportionb+h1mkot-2la y,* u omal to

  A net force F accelerates a mass up8 .ha.o vsp4b7c)6bex-ogh m with an acceleration a. If the same net force is applied to mass 2m, thenphe.o.vu-bbx 7 o6achs)48p g the acceleration will be

  A net force F acts on a mass t /vmds3 f9d. hyu*ag2m and produces an acceleration a. What acceleration results if a net force 2gy d3mvd u sf9.t*2/ahF acts on mass 4m?

  If you blow up a balloon, and then+rr*;qfj-cwnif 3n+e release it, the balloon will fly away. This is an illucn3j+ei*r -;+ nf fwrqstration of

  Two cars collide head-on. At every moment duril t-izlm( zf9)zb5.nrng 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 c z bfltri59(.nm-)zlz ar exerts on the first. This is an example of

  If you exert a force F o z.e6ti6ept pw/r+2wwn an object, the force which the object exerts on you willwpw2+twpe r.6/e tzi6

  Action-reaction forc)n5 )up*xdsu ves

  Action-reaction forcet v a2/qkfs; ,n/os3uds are

  A 20-ton truck collides with a 1500-lb car ff4 9dq-tg/j/kv/ vr 6pdt6qnand causes a lot of damage to the car. Since a lot of damage is done on thevfg/ /96tr/pjk 6 -dqnv tfqd4 car

  An object of mass m sits on a fl;xe tt+6-yrx j1 k,hn+h 6jighat table. The Earth pulls on this object with force mg, which we will call the action force. What is the reaction force?;xy + nh+r,6-xkei1 htghtjj6

  A child's toy is suspended from th kb-3 hyzbkv5v1j+ae. p c:l.ddx8l 6ze 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 forz. h6a.zxv+ddb j53k8lvkpcy1:el -bce"?

  Your bat hits the ball pitched to you with a 1500-N instantan6 rc5kvy8/hg jeous force. The ball hits the bat with an instantaneou68ck hv5y/ jgrs force, whose magnitude is

State Newton's three laws.*-uebrx7a(twf6bzg wa j2n3g 8be.w 3

  Mass and weight

  The acceleration due to gravity is lower on the Moon than on Ey(10ap.4 u s3lynmed larth. Which of the following is true about the mass and weight of an ap. 1 y3uydlsn(am40le stronaut on the Moon's surface, compared to Earth?

  An example of a force which acts at a tp4:7a7he.6grza 5u lmqta ; idistance is

  Who has a greater weight to mass ratio, a person weighing 400 N or a person wevgfgn9 i9,2cx ighing 600 g9 ,x2gcin9fv N?

  A stone is thrown straight up. At the top of its path, the net force actingqu qasj s/7pq3b5bc 6rs/9pw * on ssq/*jr3 c5p asqw p/bu796qbit is

  A 20-N weight and a 5.0-N weight are dropped simultaneously fr(jx l+d)d-g v pu2d3jeom the same height. (xj )3ej-vdpulgdd+2 Ignore air resistance. Compare their accelerations.

  A brick and a feather fallf 286 (ggbavrx30jr9 )xp -m7eloni et to the earth at their respective terminal velocities. Which objlrnaxib97epvg )rt8(6jm -f2 x 3oge0ect experiences the greater force of air friction?

  An object of mass m is han ad;b j*nep*g)ging by a string from the ceiling of an elevator. The elevator is moving up at constant speed. What is the tension d*;*p e) jgnabin the string?

  An object of mass m is hanging by a string from the ceiling oo5 lffpugi0 3/g oct xb51n8f-f an elevator. The elevator is moving upward, but slowing down. What is the tension in /opf 0f-c 81gui5tgfn3bxlo5 the string?

  The force that keeps you from sliding on an irt)3t3er-mmwa 4o t o/cy sidewalk is

  It's more difficult to start moving a heavy cu;16kd :spq zqarton from rest than it is to keep pushing it with constant velocity,s1q d:z; pu6kq because

  A horizontal force accelerates7sm41j c (upos 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 force17c sjpu(som4 is doubled. What happens to the box's acceleration?

  A packing crate slides down an inclined ramp at co8bwqipibg,s 0wbsl4 v*5:g488l bq qvnstant velocity. Thus we can deducebql0q4 8b : *g,s5s4 iwplvwv8bg8iqb that

  A block of mass M slides do )fr9 uv6m s4h,hbt*dpj5+nidwn a frictionless plane inclined at an angle q with the horizontal. The normal reacti6b vf)s4r9mtjh,pi 5 ud*h+n don force exerted by the plane on the block is

  A block of mass M slides down a frictionlessqci+plh 0ao z+flgkey61+i. / plane inclined at an angle q with the horizontal. The normal reaction force exerted by the plane on the blockhpy+qk++egaiclf10 6 o.li/z is directed

  A block of mass M slides down a frictionless plane inclined atd)2st 7e/wzmx5i952m s b-8s biixrxq an angle q with the horizontal. The gravitational f2z5s dim7qb8irmsbix)5xxes 2t 9-/w orce is directed

  Two toy cars (16 kg an2za z i;nc,w4jd 2.0 kg) are released simultaneously on an inclined plane that mak zn4aw i2jcz;,es an angle of 30e with the horizontal. Make a statement which best describes their acceleration after being released.

  An object sits on a frictionless surface.g815 r6me/udxmqs5 j:8mzr wi A 16-N force is applied to the object, and it accel1ie/:m855qmjrd s 8m ug z6wrxerates at $2.0 \; m/s^2$. What is the mass of the object?

  A sports car of mass 1000 kg can accelerate from repb4,,gshsy52wf u7pa st to 27 m/s in 7.0 s. What is the avewspyap , u4b2f ,hg7s5rage forward force on the car?

  Starting from rest, a 4.0-kg body reaches a speed orm4z.2 trc4ao f 8.0 m/s in 2.0 s. What is ttr 4ma2 c4z.rohe net force acting on the body?

  An antitank weapon fires a 3.00-kg rocket which acquires a speed of 50.0 m/s af+j9f0(s0cx :b/ tsv fmlhtz(h ter tra+:vmzbljfhf(t0/9 x t(hss0c veling
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 10-9 v7 -6clgwfzykg mass from re9gy7vw fl-z6cst,

  What is the mass of a persrb18chor zh 6nu2f6 8lig8. xjon who weighs 110 lb?

  What is the mass of an object that weighs 250 N on the surface of the Earth wtr(w+qd lxq 23b zks r c*rxr,q/q6q03here thr 230w*s3q 6txcrqrdqx rqkz ,l(q b/+e acceleration due to gravity is $9.80 \; m/s^2$?

  An object has a mass of 60 kg on thjq c8rv 0ar ,dq)3lnn-e Earth. What is the mass of the object on the surface of the Moon where the acceleration due to gravity is onlyv8n,- r)nr03jld caqq 1/6 of that on the Earth?

  Object A weighs 40 N on Earthv*6f/ge y m1sq, and object B weighs 40 N on the Moon. The Moon's gravity is one sixth of E efmqs6*1 /ygvarth's. Compare the masses of the objects.

  Sue and Sean are having a tug-of-war by pulling on opposite ends k/w o/+ebr6jkr dok5 3fvn0j:6 hm*kb of a 5.0-kg rope. Sue pulls with a 15-N force. What is Sean's force if the rope accelerates tkvkj eo6rk:jr/bkm3f nb /h+dw5o0 6*oward Sue at $2.0 \; m/s^2$?

  A stack of books rests on a9j70zr7l 9hfjpru e1b level frictionless surface. A force F acts on the staf0br 1 7j prju9ez79lhck, 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 Np 7h8y k,degr rgwv y;(+9e2sx stands on a scale in an elevator. What will the scale be reading when the elevat 8gw; vhyy9se(x +72pkrrd, geor is accelerating downward at $4.00 \; m/s^2$?

  A person on a scale rides in an elevaz6cd tp h3t,*zis*2wezc l7 /6ad(l eoalt8 .ptor. If the mass of the person is 60.0 kg anlc e pz/p (66z2dt 8lt3d szawcai.,*lhe7t*od 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 ta7 z ja+n3 v1ihwyf)9xhe person is 60.0 kg and the elevator accelerates upway)9 z fw+1ha7vjni3axrd with an acceleration of $4.90 \; m/s^2$, what is the reading on the scale?

  Two horizontal forces act on a 5.)t b2*ob0b sys0-kg mass. One force has a magnitude of 8.0 N and is directed due north. The second force toward the*2)ot0b bysbs 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: ee8m5y.f6bcrmgx+t)7bk;o swms t- 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 minimte8m-m6+tmkgs7fb wb e.r)s ;y: oxc5 um 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 truckh fx qtq35l/8g*qyw zc5.zbl*df5ll5. It is held in place by metal brackets that can qqw* l5qh dczll8g3f 5.fbx lz */t55yexert 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 the cab?

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kg and m71) g)mtmb n6jb,wkorv6o;t u lro42 h = 0.40 kg, what is the magnitude of the a;vm1lr4) j, b2r 6um7obo 6twt)hngkocceleration of the system? (Ignore friction and the mass of the pulley.)

  In the Atwood machine shown in Fig. 4-1, if M = 0.60 kgz.yg/y + ;mgbh and m = 0.40 kg, what is the tenshz;my+ g./by gion in the string? (Ignore friction and the mass of the pulley.)

  A student pulls a box of books on a smt2amh42 a, ymdooth horizontal floor with a force of 100 N in a dir42a2 ,dhma mytection 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 esqkzox-94 7 */ bbdajbooks 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 t4ae * k -b97zosdjq/xbhe books is 40.0 kg, what is the normal force on the box?

  A traffic light of weight 100 N inczin90ny. c:c a.qk36oukx e9wn5h / s supported by two ropes as shown in Fig. 4-2. What are the tensions in thcewckuo9i30n/5x.an:n n.k q 9zh6y ce ropes?

  In Fig. 4-2, if the tensions in the ropes are 50 N, what is the mass ov l09+g hmmj an-un/y,f the traffn man0hlgm/-9uj y +v,ic light?

  Two boxes of masses m and 2m are ioghe:ihx fzsxrzd)l 56+t+90 n contact with each other on a frictionless surface+t)hhsx6 zx0 elr5di z9:gof+. (See Fig. 4-3.) What is the acceleration of the more massive box?

  Two boxes of masses m and 2m are in cont1w8 .quh it2 ts- hs;syfr9w/xact with each other on a frictionless surface. (See Fifh q- wyswt. ts;uish/x218 9rg. 4-3.) What is the net force on the more massive box?

  Two boxes of masses m and 2m are connected by a rope. (Seck+y));gbh1x4yh 5;wmtvliw e Fig. 4-4.) If the forxl b;hw yiy54gtkc ) wm)+hv;1ward force on the more massive box is F, what is the tension in the connecting rope?

  Two boxes of masses m and 2m are connected by a rope. (See Fig. 4-s v )x:muw,u.l4.) If the forward force on the more mas.xlusvuwm,: ) sive box is F, what is the acceleration of the less massive box?

Two boxes are connected by a cord running over a pulley as i0 4,p.tm mzcr2bpx r48gn)0kbjn:clshown in Fig. 4-5. Box I of m ,:p8xcg 2r)nb0mrtclknzm .jpi 044bass
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 between a 3.0-kg boxowxs nn.dw z9:3m (8tj and a desk are 0.40 and 0.30, respectively. What is the net force on the box when a 15 N horizontal force is applied to th (wmnw d.n:j3st8zo9xe box?

  The coefficients of static and kinetic frictions for plastic on wood are 0.50h.:zryw/+lf( , bchag and 0.w/hz bhlcf, (rg :+ya.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 levvvrujxqb 5.d,jb. 6 2wel surface in the +x direction. It slows and comes to a stop with a constant acceleratiow vj6vb 2du.r5b,.j qxn 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. Ahfcrn9hn:+s1k b. 0om 3.0-N friction force retards the mo:oh+rsmfhnc1bn9k .0tion. What is the acceleration of the object?

  A horizontal force of 5.08.7zn syd1/xlgqb o8x 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 initia kgzf.)j)d xwxr4-,ua x.7fa + 5cgbbol speed of 10 m/s. It slides 50 m on the ice before it stops. What is the coefficient of kinetic f+ j-)4.d,x frcabxwukagxf7z)gb o5.riction between the puck and the ice?

  During the investigation +vn(mv5 bjn/v)z lm:rof a traffic 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. Estimate the speed of the car wmn+)v jlr(/ zbn5mv: vhen the brakes were applied.

  Two boxes of masses m and 3m are stacked. (See Fig. 4-6.) The surface betwe9(t8. r snia8athgs n;en the more massive box and the horizontal surface is smooth and the surface between th;.ia9hn sn(8ta8sgrte boxes is rough. 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 3m are stacked. (See Fig. 4-6.) The surface between h.7ef8)owx 55s:mr( tugsm mithe more massive box and the horizontal surface is smooth and the surface between the boxes xsgmm5.:ius()r87 mhwfe o5t 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 bo7rmmb2 (e)oplane. The plane is inclined at an anglbe o(2m)om7b re of $30^{\circ}$ with the horizontal. What is the object's acceleration?

  A 10-kg mass slides down a flat hill tha74qcc2(*mxd y b6o+fw6xk6 gu+s cj mxt 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 plane with :ulu 8,u 8yjvkiq5 7yman 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 at an anglem0/pj+sb-tn+hrs r )g 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 dirrlt3a p-xwwqwid * 9/1ectly down an inclined plane, at a constant velocity of 6.0 m/s.w w* rdtqix/p9alw-3 1
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 dt5)up 9 mre(wmown 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 8wyb*s/q2ik ip 9jib *$37^{\circ}$ 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 lo/x/l9em vwed13a2 qrrg weighing 500 N along a rough surface. The cable attached to the log makes an angle oqerla2/ 1xrv mw39/edf $30.0^{\circ}$ 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 rele/tn yylu, k17h :uqgt*ased from rest on a rough inclined plane tilted at an angle ofq ,/ytthyu1:*7n kgul $33.5^{\circ}$ 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 pjudca.0bnrv4 xo7(u +lane. 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 between the our j bau+c.d7x(nov04bject and the plane?